diff options
author | Chris Metcalf <cmetcalf@tilera.com> | 2010-05-29 03:09:12 (GMT) |
---|---|---|
committer | Chris Metcalf <cmetcalf@tilera.com> | 2010-06-04 21:11:18 (GMT) |
commit | 867e359b97c970a60626d5d76bbe2a8fadbf38fb (patch) | |
tree | c5ccbb7f5172e8555977119608ecb1eee3cc37e3 /arch/tile/lib | |
parent | 5360bd776f73d0a7da571d72a09a03f237e99900 (diff) | |
download | linux-867e359b97c970a60626d5d76bbe2a8fadbf38fb.tar.xz |
arch/tile: core support for Tilera 32-bit chips.
This change is the core kernel support for TILEPro and TILE64 chips.
No driver support (except the console driver) is included yet.
This includes the relevant Linux headers in asm/; the low-level
low-level "Tile architecture" headers in arch/, which are
shared with the hypervisor, etc., and are build-system agnostic;
and the relevant hypervisor headers in hv/.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/tile/lib')
-rw-r--r-- | arch/tile/lib/Makefile | 16 | ||||
-rw-r--r-- | arch/tile/lib/__invalidate_icache.S | 106 | ||||
-rw-r--r-- | arch/tile/lib/atomic_32.c | 347 | ||||
-rw-r--r-- | arch/tile/lib/atomic_asm_32.S | 197 | ||||
-rw-r--r-- | arch/tile/lib/checksum.c | 102 | ||||
-rw-r--r-- | arch/tile/lib/cpumask.c | 51 | ||||
-rw-r--r-- | arch/tile/lib/delay.c | 34 | ||||
-rw-r--r-- | arch/tile/lib/exports.c | 78 | ||||
-rw-r--r-- | arch/tile/lib/mb_incoherent.S | 34 | ||||
-rw-r--r-- | arch/tile/lib/memchr_32.c | 68 | ||||
-rw-r--r-- | arch/tile/lib/memcpy_32.S | 628 | ||||
-rw-r--r-- | arch/tile/lib/memcpy_tile64.c | 271 | ||||
-rw-r--r-- | arch/tile/lib/memmove_32.c | 63 | ||||
-rw-r--r-- | arch/tile/lib/memset_32.c | 274 | ||||
-rw-r--r-- | arch/tile/lib/spinlock_32.c | 221 | ||||
-rw-r--r-- | arch/tile/lib/spinlock_common.h | 64 | ||||
-rw-r--r-- | arch/tile/lib/strchr_32.c | 66 | ||||
-rw-r--r-- | arch/tile/lib/strlen_32.c | 36 | ||||
-rw-r--r-- | arch/tile/lib/uaccess.c | 31 | ||||
-rw-r--r-- | arch/tile/lib/usercopy_32.S | 223 |
20 files changed, 2910 insertions, 0 deletions
diff --git a/arch/tile/lib/Makefile b/arch/tile/lib/Makefile new file mode 100644 index 0000000..ea9c209 --- /dev/null +++ b/arch/tile/lib/Makefile @@ -0,0 +1,16 @@ +# +# Makefile for TILE-specific library files.. +# + +lib-y = checksum.o cpumask.o delay.o __invalidate_icache.o \ + mb_incoherent.o uaccess.o \ + memcpy_$(BITS).o memchr_$(BITS).o memmove_$(BITS).o memset_$(BITS).o \ + strchr_$(BITS).o strlen_$(BITS).o + +ifneq ($(CONFIG_TILEGX),y) +lib-y += atomic_32.o atomic_asm_32.o memcpy_tile64.o +endif + +lib-$(CONFIG_SMP) += spinlock_$(BITS).o usercopy_$(BITS).o + +obj-$(CONFIG_MODULES) += exports.o diff --git a/arch/tile/lib/__invalidate_icache.S b/arch/tile/lib/__invalidate_icache.S new file mode 100644 index 0000000..92e7050 --- /dev/null +++ b/arch/tile/lib/__invalidate_icache.S @@ -0,0 +1,106 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * A routine for synchronizing the instruction and data caches. + * Useful for self-modifying code. + * + * r0 holds the buffer address + * r1 holds the size in bytes + */ + +#include <arch/chip.h> +#include <feedback.h> + +#if defined(__NEWLIB__) || defined(__BME__) +#include <sys/page.h> +#else +#include <asm/page.h> +#endif + +#ifdef __tilegx__ +/* Share code among Tile family chips but adjust opcodes appropriately. */ +#define slt cmpltu +#define bbst blbst +#define bnezt bnzt +#endif + +#if defined(__tilegx__) && __SIZEOF_POINTER__ == 4 +/* Force 32-bit ops so pointers wrap around appropriately. */ +#define ADD_PTR addx +#define ADDI_PTR addxi +#else +#define ADD_PTR add +#define ADDI_PTR addi +#endif + + .section .text.__invalidate_icache, "ax" + .global __invalidate_icache + .type __invalidate_icache,@function + .hidden __invalidate_icache + .align 8 +__invalidate_icache: + FEEDBACK_ENTER(__invalidate_icache) + { + ADD_PTR r1, r0, r1 /* end of buffer */ + blez r1, .Lexit /* skip out if size <= 0 */ + } + { + ADDI_PTR r1, r1, -1 /* point to last byte to flush */ + andi r0, r0, -CHIP_L1I_LINE_SIZE() /* align to cache-line size */ + } + { + andi r1, r1, -CHIP_L1I_LINE_SIZE() /* last cache line to flush */ + mf + } +#if CHIP_L1I_CACHE_SIZE() > PAGE_SIZE + { + moveli r4, CHIP_L1I_CACHE_SIZE() / PAGE_SIZE /* loop counter */ + move r2, r0 /* remember starting address */ + } +#endif + drain + { + slt r3, r0, r1 /* set up loop invariant */ +#if CHIP_L1I_CACHE_SIZE() > PAGE_SIZE + moveli r6, PAGE_SIZE +#endif + } +.Lentry: + { + icoh r0 + ADDI_PTR r0, r0, CHIP_L1I_LINE_SIZE() /* advance buffer */ + } + { + slt r3, r0, r1 /* check if buffer < buffer + size */ + bbst r3, .Lentry /* loop if buffer < buffer + size */ + } +#if CHIP_L1I_CACHE_SIZE() > PAGE_SIZE + { + ADD_PTR r2, r2, r6 + ADD_PTR r1, r1, r6 + } + { + move r0, r2 + addi r4, r4, -1 + } + { + slt r3, r0, r1 /* set up loop invariant */ + bnezt r4, .Lentry + } +#endif + drain +.Lexit: + jrp lr + +.Lend___invalidate_icache: + .size __invalidate_icache, \ + .Lend___invalidate_icache - __invalidate_icache diff --git a/arch/tile/lib/atomic_32.c b/arch/tile/lib/atomic_32.c new file mode 100644 index 0000000..be1e8ac --- /dev/null +++ b/arch/tile/lib/atomic_32.c @@ -0,0 +1,347 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/cache.h> +#include <linux/delay.h> +#include <linux/uaccess.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <asm/atomic.h> +#include <arch/chip.h> + +/* The routines in atomic_asm.S are private, so we only declare them here. */ +extern struct __get_user __atomic_cmpxchg(volatile int *p, + int *lock, int o, int n); +extern struct __get_user __atomic_xchg(volatile int *p, int *lock, int n); +extern struct __get_user __atomic_xchg_add(volatile int *p, int *lock, int n); +extern struct __get_user __atomic_xchg_add_unless(volatile int *p, + int *lock, int o, int n); +extern struct __get_user __atomic_or(volatile int *p, int *lock, int n); +extern struct __get_user __atomic_andn(volatile int *p, int *lock, int n); +extern struct __get_user __atomic_xor(volatile int *p, int *lock, int n); + +extern u64 __atomic64_cmpxchg(volatile u64 *p, int *lock, u64 o, u64 n); +extern u64 __atomic64_xchg(volatile u64 *p, int *lock, u64 n); +extern u64 __atomic64_xchg_add(volatile u64 *p, int *lock, u64 n); +extern u64 __atomic64_xchg_add_unless(volatile u64 *p, + int *lock, u64 o, u64 n); + + +/* See <asm/atomic.h> */ +#if ATOMIC_LOCKS_FOUND_VIA_TABLE() + +/* + * A block of memory containing locks for atomic ops. Each instance of this + * struct will be homed on a different CPU. + */ +struct atomic_locks_on_cpu { + int lock[ATOMIC_HASH_L2_SIZE]; +} __attribute__((aligned(ATOMIC_HASH_L2_SIZE * 4))); + +static DEFINE_PER_CPU(struct atomic_locks_on_cpu, atomic_lock_pool); + +/* The locks we'll use until __init_atomic_per_cpu is called. */ +static struct atomic_locks_on_cpu __initdata initial_atomic_locks; + +/* Hash into this vector to get a pointer to lock for the given atomic. */ +struct atomic_locks_on_cpu *atomic_lock_ptr[ATOMIC_HASH_L1_SIZE] + __write_once = { + [0 ... ATOMIC_HASH_L1_SIZE-1] (&initial_atomic_locks) +}; + +#else /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */ + +/* This page is remapped on startup to be hash-for-home. */ +int atomic_locks[PAGE_SIZE / sizeof(int) /* Only ATOMIC_HASH_SIZE is used */] + __attribute__((aligned(PAGE_SIZE), section(".bss.page_aligned"))); + +#endif /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */ + +static inline int *__atomic_hashed_lock(volatile void *v) +{ + /* NOTE: this code must match "sys_cmpxchg" in kernel/intvec.S */ +#if ATOMIC_LOCKS_FOUND_VIA_TABLE() + unsigned long i = + (unsigned long) v & ((PAGE_SIZE-1) & -sizeof(long long)); + unsigned long n = __insn_crc32_32(0, i); + + /* Grab high bits for L1 index. */ + unsigned long l1_index = n >> ((sizeof(n) * 8) - ATOMIC_HASH_L1_SHIFT); + /* Grab low bits for L2 index. */ + unsigned long l2_index = n & (ATOMIC_HASH_L2_SIZE - 1); + + return &atomic_lock_ptr[l1_index]->lock[l2_index]; +#else + /* + * Use bits [3, 3 + ATOMIC_HASH_SHIFT) as the lock index. + * Using mm works here because atomic_locks is page aligned. + */ + unsigned long ptr = __insn_mm((unsigned long)v >> 1, + (unsigned long)atomic_locks, + 2, (ATOMIC_HASH_SHIFT + 2) - 1); + return (int *)ptr; +#endif +} + +#ifdef CONFIG_SMP +/* Return whether the passed pointer is a valid atomic lock pointer. */ +static int is_atomic_lock(int *p) +{ +#if ATOMIC_LOCKS_FOUND_VIA_TABLE() + int i; + for (i = 0; i < ATOMIC_HASH_L1_SIZE; ++i) { + + if (p >= &atomic_lock_ptr[i]->lock[0] && + p < &atomic_lock_ptr[i]->lock[ATOMIC_HASH_L2_SIZE]) { + return 1; + } + } + return 0; +#else + return p >= &atomic_locks[0] && p < &atomic_locks[ATOMIC_HASH_SIZE]; +#endif +} + +void __atomic_fault_unlock(int *irqlock_word) +{ + BUG_ON(!is_atomic_lock(irqlock_word)); + BUG_ON(*irqlock_word != 1); + *irqlock_word = 0; +} + +#endif /* CONFIG_SMP */ + +static inline int *__atomic_setup(volatile void *v) +{ + /* Issue a load to the target to bring it into cache. */ + *(volatile int *)v; + return __atomic_hashed_lock(v); +} + +int _atomic_xchg(atomic_t *v, int n) +{ + return __atomic_xchg(&v->counter, __atomic_setup(v), n).val; +} +EXPORT_SYMBOL(_atomic_xchg); + +int _atomic_xchg_add(atomic_t *v, int i) +{ + return __atomic_xchg_add(&v->counter, __atomic_setup(v), i).val; +} +EXPORT_SYMBOL(_atomic_xchg_add); + +int _atomic_xchg_add_unless(atomic_t *v, int a, int u) +{ + /* + * Note: argument order is switched here since it is easier + * to use the first argument consistently as the "old value" + * in the assembly, as is done for _atomic_cmpxchg(). + */ + return __atomic_xchg_add_unless(&v->counter, __atomic_setup(v), u, a) + .val; +} +EXPORT_SYMBOL(_atomic_xchg_add_unless); + +int _atomic_cmpxchg(atomic_t *v, int o, int n) +{ + return __atomic_cmpxchg(&v->counter, __atomic_setup(v), o, n).val; +} +EXPORT_SYMBOL(_atomic_cmpxchg); + +unsigned long _atomic_or(volatile unsigned long *p, unsigned long mask) +{ + return __atomic_or((int *)p, __atomic_setup(p), mask).val; +} +EXPORT_SYMBOL(_atomic_or); + +unsigned long _atomic_andn(volatile unsigned long *p, unsigned long mask) +{ + return __atomic_andn((int *)p, __atomic_setup(p), mask).val; +} +EXPORT_SYMBOL(_atomic_andn); + +unsigned long _atomic_xor(volatile unsigned long *p, unsigned long mask) +{ + return __atomic_xor((int *)p, __atomic_setup(p), mask).val; +} +EXPORT_SYMBOL(_atomic_xor); + + +u64 _atomic64_xchg(atomic64_t *v, u64 n) +{ + return __atomic64_xchg(&v->counter, __atomic_setup(v), n); +} +EXPORT_SYMBOL(_atomic64_xchg); + +u64 _atomic64_xchg_add(atomic64_t *v, u64 i) +{ + return __atomic64_xchg_add(&v->counter, __atomic_setup(v), i); +} +EXPORT_SYMBOL(_atomic64_xchg_add); + +u64 _atomic64_xchg_add_unless(atomic64_t *v, u64 a, u64 u) +{ + /* + * Note: argument order is switched here since it is easier + * to use the first argument consistently as the "old value" + * in the assembly, as is done for _atomic_cmpxchg(). + */ + return __atomic64_xchg_add_unless(&v->counter, __atomic_setup(v), + u, a); +} +EXPORT_SYMBOL(_atomic64_xchg_add_unless); + +u64 _atomic64_cmpxchg(atomic64_t *v, u64 o, u64 n) +{ + return __atomic64_cmpxchg(&v->counter, __atomic_setup(v), o, n); +} +EXPORT_SYMBOL(_atomic64_cmpxchg); + + +static inline int *__futex_setup(__user int *v) +{ + /* + * Issue a prefetch to the counter to bring it into cache. + * As for __atomic_setup, but we can't do a read into the L1 + * since it might fault; instead we do a prefetch into the L2. + */ + __insn_prefetch(v); + return __atomic_hashed_lock(v); +} + +struct __get_user futex_set(int *v, int i) +{ + return __atomic_xchg(v, __futex_setup(v), i); +} + +struct __get_user futex_add(int *v, int n) +{ + return __atomic_xchg_add(v, __futex_setup(v), n); +} + +struct __get_user futex_or(int *v, int n) +{ + return __atomic_or(v, __futex_setup(v), n); +} + +struct __get_user futex_andn(int *v, int n) +{ + return __atomic_andn(v, __futex_setup(v), n); +} + +struct __get_user futex_xor(int *v, int n) +{ + return __atomic_xor(v, __futex_setup(v), n); +} + +struct __get_user futex_cmpxchg(int *v, int o, int n) +{ + return __atomic_cmpxchg(v, __futex_setup(v), o, n); +} + +/* + * If any of the atomic or futex routines hit a bad address (not in + * the page tables at kernel PL) this routine is called. The futex + * routines are never used on kernel space, and the normal atomics and + * bitops are never used on user space. So a fault on kernel space + * must be fatal, but a fault on userspace is a futex fault and we + * need to return -EFAULT. Note that the context this routine is + * invoked in is the context of the "_atomic_xxx()" routines called + * by the functions in this file. + */ +struct __get_user __atomic_bad_address(int *addr) +{ + if (unlikely(!access_ok(VERIFY_WRITE, addr, sizeof(int)))) + panic("Bad address used for kernel atomic op: %p\n", addr); + return (struct __get_user) { .err = -EFAULT }; +} + + +#if CHIP_HAS_CBOX_HOME_MAP() +static int __init noatomichash(char *str) +{ + printk("noatomichash is deprecated.\n"); + return 1; +} +__setup("noatomichash", noatomichash); +#endif + +void __init __init_atomic_per_cpu(void) +{ +#if ATOMIC_LOCKS_FOUND_VIA_TABLE() + + unsigned int i; + int actual_cpu; + + /* + * Before this is called from setup, we just have one lock for + * all atomic objects/operations. Here we replace the + * elements of atomic_lock_ptr so that they point at per_cpu + * integers. This seemingly over-complex approach stems from + * the fact that DEFINE_PER_CPU defines an entry for each cpu + * in the grid, not each cpu from 0..ATOMIC_HASH_SIZE-1. But + * for efficient hashing of atomics to their locks we want a + * compile time constant power of 2 for the size of this + * table, so we use ATOMIC_HASH_SIZE. + * + * Here we populate atomic_lock_ptr from the per cpu + * atomic_lock_pool, interspersing by actual cpu so that + * subsequent elements are homed on consecutive cpus. + */ + + actual_cpu = cpumask_first(cpu_possible_mask); + + for (i = 0; i < ATOMIC_HASH_L1_SIZE; ++i) { + /* + * Preincrement to slightly bias against using cpu 0, + * which has plenty of stuff homed on it already. + */ + actual_cpu = cpumask_next(actual_cpu, cpu_possible_mask); + if (actual_cpu >= nr_cpu_ids) + actual_cpu = cpumask_first(cpu_possible_mask); + + atomic_lock_ptr[i] = &per_cpu(atomic_lock_pool, actual_cpu); + } + +#else /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */ + + /* Validate power-of-two and "bigger than cpus" assumption */ + BUG_ON(ATOMIC_HASH_SIZE & (ATOMIC_HASH_SIZE-1)); + BUG_ON(ATOMIC_HASH_SIZE < nr_cpu_ids); + + /* + * On TILEPro we prefer to use a single hash-for-home + * page, since this means atomic operations are less + * likely to encounter a TLB fault and thus should + * in general perform faster. You may wish to disable + * this in situations where few hash-for-home tiles + * are configured. + */ + BUG_ON((unsigned long)atomic_locks % PAGE_SIZE != 0); + + /* The locks must all fit on one page. */ + BUG_ON(ATOMIC_HASH_SIZE * sizeof(int) > PAGE_SIZE); + + /* + * We use the page offset of the atomic value's address as + * an index into atomic_locks, excluding the low 3 bits. + * That should not produce more indices than ATOMIC_HASH_SIZE. + */ + BUG_ON((PAGE_SIZE >> 3) > ATOMIC_HASH_SIZE); + +#endif /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */ + + /* The futex code makes this assumption, so we validate it here. */ + BUG_ON(sizeof(atomic_t) != sizeof(int)); +} diff --git a/arch/tile/lib/atomic_asm_32.S b/arch/tile/lib/atomic_asm_32.S new file mode 100644 index 0000000..c0d0585 --- /dev/null +++ b/arch/tile/lib/atomic_asm_32.S @@ -0,0 +1,197 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * + * Support routines for atomic operations. Each function takes: + * + * r0: address to manipulate + * r1: pointer to atomic lock guarding this operation (for FUTEX_LOCK_REG) + * r2: new value to write, or for cmpxchg/add_unless, value to compare against + * r3: (cmpxchg/xchg_add_unless) new value to write or add; + * (atomic64 ops) high word of value to write + * r4/r5: (cmpxchg64/add_unless64) new value to write or add + * + * The 32-bit routines return a "struct __get_user" so that the futex code + * has an opportunity to return -EFAULT to the user if needed. + * The 64-bit routines just return a "long long" with the value, + * since they are only used from kernel space and don't expect to fault. + * Support for 16-bit ops is included in the framework but we don't provide + * any (x86_64 has an atomic_inc_short(), so we might want to some day). + * + * Note that the caller is advised to issue a suitable L1 or L2 + * prefetch on the address being manipulated to avoid extra stalls. + * In addition, the hot path is on two icache lines, and we start with + * a jump to the second line to make sure they are both in cache so + * that we never stall waiting on icache fill while holding the lock. + * (This doesn't work out with most 64-bit ops, since they consume + * too many bundles, so may take an extra i-cache stall.) + * + * These routines set the INTERRUPT_CRITICAL_SECTION bit, just + * like sys_cmpxchg(), so that NMIs like PERF_COUNT will not interrupt + * the code, just page faults. + * + * If the load or store faults in a way that can be directly fixed in + * the do_page_fault_ics() handler (e.g. a vmalloc reference) we fix it + * directly, return to the instruction that faulted, and retry it. + * + * If the load or store faults in a way that potentially requires us + * to release the atomic lock, then retry (e.g. a migrating PTE), we + * reset the PC in do_page_fault_ics() to the "tns" instruction so + * that on return we will reacquire the lock and restart the op. We + * are somewhat overloading the exception_table_entry notion by doing + * this, since those entries are not normally used for migrating PTEs. + * + * If the main page fault handler discovers a bad address, it will see + * the PC pointing to the "tns" instruction (due to the earlier + * exception_table_entry processing in do_page_fault_ics), and + * re-reset the PC to the fault handler, atomic_bad_address(), which + * effectively takes over from the atomic op and can either return a + * bad "struct __get_user" (for user addresses) or can just panic (for + * bad kernel addresses). + * + * Note that if the value we would store is the same as what we + * loaded, we bypass the load. Other platforms with true atomics can + * make the guarantee that a non-atomic __clear_bit(), for example, + * can safely race with an atomic test_and_set_bit(); this example is + * from bit_spinlock.h in slub_lock() / slub_unlock(). We can't do + * that on Tile since the "atomic" op is really just a + * read/modify/write, and can race with the non-atomic + * read/modify/write. However, if we can short-circuit the write when + * it is not needed, in the atomic case, we avoid the race. + */ + +#include <linux/linkage.h> +#include <asm/atomic.h> +#include <asm/page.h> +#include <asm/processor.h> + + .section .text.atomic,"ax" +ENTRY(__start_atomic_asm_code) + + .macro atomic_op, name, bitwidth, body + .align 64 +STD_ENTRY_SECTION(__atomic\name, .text.atomic) + { + movei r24, 1 + j 4f /* branch to second cache line */ + } +1: { + .ifc \bitwidth,16 + lh r22, r0 + .else + lw r22, r0 + addi r23, r0, 4 + .endif + } + .ifc \bitwidth,64 + lw r23, r23 + .endif + \body /* set r24, and r25 if 64-bit */ + { + seq r26, r22, r24 + seq r27, r23, r25 + } + .ifc \bitwidth,64 + bbnst r27, 2f + .endif + bbs r26, 3f /* skip write-back if it's the same value */ +2: { + .ifc \bitwidth,16 + sh r0, r24 + .else + sw r0, r24 + addi r23, r0, 4 + .endif + } + .ifc \bitwidth,64 + sw r23, r25 + .endif + mf +3: { + move r0, r22 + .ifc \bitwidth,64 + move r1, r23 + .else + move r1, zero + .endif + sw ATOMIC_LOCK_REG_NAME, zero + } + mtspr INTERRUPT_CRITICAL_SECTION, zero + jrp lr +4: { + move ATOMIC_LOCK_REG_NAME, r1 + mtspr INTERRUPT_CRITICAL_SECTION, r24 + } +#ifndef CONFIG_SMP + j 1b /* no atomic locks */ +#else + { + tns r21, ATOMIC_LOCK_REG_NAME + moveli r23, 2048 /* maximum backoff time in cycles */ + } + { + bzt r21, 1b /* branch if lock acquired */ + moveli r25, 32 /* starting backoff time in cycles */ + } +5: mtspr INTERRUPT_CRITICAL_SECTION, zero + mfspr r26, CYCLE_LOW /* get start point for this backoff */ +6: mfspr r22, CYCLE_LOW /* test to see if we've backed off enough */ + sub r22, r22, r26 + slt r22, r22, r25 + bbst r22, 6b + { + mtspr INTERRUPT_CRITICAL_SECTION, r24 + shli r25, r25, 1 /* double the backoff; retry the tns */ + } + { + tns r21, ATOMIC_LOCK_REG_NAME + slt r26, r23, r25 /* is the proposed backoff too big? */ + } + { + bzt r21, 1b /* branch if lock acquired */ + mvnz r25, r26, r23 + } + j 5b +#endif + STD_ENDPROC(__atomic\name) + .ifc \bitwidth,32 + .pushsection __ex_table,"a" + .word 1b, __atomic\name + .word 2b, __atomic\name + .word __atomic\name, __atomic_bad_address + .popsection + .endif + .endm + +atomic_op _cmpxchg, 32, "seq r26, r22, r2; { bbns r26, 3f; move r24, r3 }" +atomic_op _xchg, 32, "move r24, r2" +atomic_op _xchg_add, 32, "add r24, r22, r2" +atomic_op _xchg_add_unless, 32, \ + "sne r26, r22, r2; { bbns r26, 3f; add r24, r22, r3 }" +atomic_op _or, 32, "or r24, r22, r2" +atomic_op _andn, 32, "nor r2, r2, zero; and r24, r22, r2" +atomic_op _xor, 32, "xor r24, r22, r2" + +atomic_op 64_cmpxchg, 64, "{ seq r26, r22, r2; seq r27, r23, r3 }; \ + { bbns r26, 3f; move r24, r4 }; { bbns r27, 3f; move r25, r5 }" +atomic_op 64_xchg, 64, "{ move r24, r2; move r25, r3 }" +atomic_op 64_xchg_add, 64, "{ add r24, r22, r2; add r25, r23, r3 }; \ + slt_u r26, r24, r22; add r25, r25, r26" +atomic_op 64_xchg_add_unless, 64, \ + "{ sne r26, r22, r2; sne r27, r23, r3 }; \ + { bbns r26, 3f; add r24, r22, r4 }; \ + { bbns r27, 3f; add r25, r23, r5 }; \ + slt_u r26, r24, r22; add r25, r25, r26" + + jrp lr /* happy backtracer */ + +ENTRY(__end_atomic_asm_code) diff --git a/arch/tile/lib/checksum.c b/arch/tile/lib/checksum.c new file mode 100644 index 0000000..e4bab5b --- /dev/null +++ b/arch/tile/lib/checksum.c @@ -0,0 +1,102 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * Support code for the main lib/checksum.c. + */ + +#include <net/checksum.h> +#include <linux/module.h> + +static inline unsigned int longto16(unsigned long x) +{ + unsigned long ret; +#ifdef __tilegx__ + ret = __insn_v2sadu(x, 0); + ret = __insn_v2sadu(ret, 0); +#else + ret = __insn_sadh_u(x, 0); + ret = __insn_sadh_u(ret, 0); +#endif + return ret; +} + +__wsum do_csum(const unsigned char *buff, int len) +{ + int odd, count; + unsigned long result = 0; + + if (len <= 0) + goto out; + odd = 1 & (unsigned long) buff; + if (odd) { + result = (*buff << 8); + len--; + buff++; + } + count = len >> 1; /* nr of 16-bit words.. */ + if (count) { + if (2 & (unsigned long) buff) { + result += *(const unsigned short *)buff; + count--; + len -= 2; + buff += 2; + } + count >>= 1; /* nr of 32-bit words.. */ + if (count) { +#ifdef __tilegx__ + if (4 & (unsigned long) buff) { + unsigned int w = *(const unsigned int *)buff; + result = __insn_v2sadau(result, w, 0); + count--; + len -= 4; + buff += 4; + } + count >>= 1; /* nr of 64-bit words.. */ +#endif + + /* + * This algorithm could wrap around for very + * large buffers, but those should be impossible. + */ + BUG_ON(count >= 65530); + + while (count) { + unsigned long w = *(const unsigned long *)buff; + count--; + buff += sizeof(w); +#ifdef __tilegx__ + result = __insn_v2sadau(result, w, 0); +#else + result = __insn_sadah_u(result, w, 0); +#endif + } +#ifdef __tilegx__ + if (len & 4) { + unsigned int w = *(const unsigned int *)buff; + result = __insn_v2sadau(result, w, 0); + buff += 4; + } +#endif + } + if (len & 2) { + result += *(const unsigned short *) buff; + buff += 2; + } + } + if (len & 1) + result += *buff; + result = longto16(result); + if (odd) + result = swab16(result); +out: + return result; +} diff --git a/arch/tile/lib/cpumask.c b/arch/tile/lib/cpumask.c new file mode 100644 index 0000000..af745b3 --- /dev/null +++ b/arch/tile/lib/cpumask.c @@ -0,0 +1,51 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/cpumask.h> +#include <linux/ctype.h> +#include <linux/errno.h> + +/* + * Allow cropping out bits beyond the end of the array. + * Move to "lib" directory if more clients want to use this routine. + */ +int bitmap_parselist_crop(const char *bp, unsigned long *maskp, int nmaskbits) +{ + unsigned a, b; + + bitmap_zero(maskp, nmaskbits); + do { + if (!isdigit(*bp)) + return -EINVAL; + a = simple_strtoul(bp, (char **)&bp, 10); + b = a; + if (*bp == '-') { + bp++; + if (!isdigit(*bp)) + return -EINVAL; + b = simple_strtoul(bp, (char **)&bp, 10); + } + if (!(a <= b)) + return -EINVAL; + if (b >= nmaskbits) + b = nmaskbits-1; + while (a <= b) { + set_bit(a, maskp); + a++; + } + if (*bp == ',') + bp++; + } while (*bp != '\0' && *bp != '\n'); + return 0; +} diff --git a/arch/tile/lib/delay.c b/arch/tile/lib/delay.c new file mode 100644 index 0000000..5801b03 --- /dev/null +++ b/arch/tile/lib/delay.c @@ -0,0 +1,34 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/thread_info.h> +#include <asm/fixmap.h> +#include <hv/hypervisor.h> + +void __udelay(unsigned long usecs) +{ + hv_nanosleep(usecs * 1000); +} +EXPORT_SYMBOL(__udelay); + +void __ndelay(unsigned long nsecs) +{ + hv_nanosleep(nsecs); +} +EXPORT_SYMBOL(__ndelay); + +/* FIXME: should be declared in a header somewhere. */ +EXPORT_SYMBOL(__delay); diff --git a/arch/tile/lib/exports.c b/arch/tile/lib/exports.c new file mode 100644 index 0000000..af8e70e --- /dev/null +++ b/arch/tile/lib/exports.c @@ -0,0 +1,78 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * + * Exports from assembler code and from libtile-cc. + */ + +#include <linux/module.h> + +/* arch/tile/lib/usercopy.S */ +#include <linux/uaccess.h> +EXPORT_SYMBOL(__get_user_1); +EXPORT_SYMBOL(__get_user_2); +EXPORT_SYMBOL(__get_user_4); +EXPORT_SYMBOL(__put_user_1); +EXPORT_SYMBOL(__put_user_2); +EXPORT_SYMBOL(__put_user_4); +EXPORT_SYMBOL(__put_user_8); +EXPORT_SYMBOL(strnlen_user_asm); +EXPORT_SYMBOL(strncpy_from_user_asm); +EXPORT_SYMBOL(clear_user_asm); + +/* arch/tile/kernel/entry.S */ +#include <linux/kernel.h> +#include <asm/processor.h> +EXPORT_SYMBOL(current_text_addr); +EXPORT_SYMBOL(dump_stack); + +/* arch/tile/lib/__memcpy.S */ +/* NOTE: on TILE64, these symbols appear in arch/tile/lib/memcpy_tile64.c */ +EXPORT_SYMBOL(memcpy); +EXPORT_SYMBOL(__copy_to_user_inatomic); +EXPORT_SYMBOL(__copy_from_user_inatomic); +EXPORT_SYMBOL(__copy_from_user_zeroing); + +/* hypervisor glue */ +#include <hv/hypervisor.h> +EXPORT_SYMBOL(hv_dev_open); +EXPORT_SYMBOL(hv_dev_pread); +EXPORT_SYMBOL(hv_dev_pwrite); +EXPORT_SYMBOL(hv_dev_close); + +/* -ltile-cc */ +uint32_t __udivsi3(uint32_t dividend, uint32_t divisor); +EXPORT_SYMBOL(__udivsi3); +int32_t __divsi3(int32_t dividend, int32_t divisor); +EXPORT_SYMBOL(__divsi3); +uint64_t __udivdi3(uint64_t dividend, uint64_t divisor); +EXPORT_SYMBOL(__udivdi3); +int64_t __divdi3(int64_t dividend, int64_t divisor); +EXPORT_SYMBOL(__divdi3); +uint32_t __umodsi3(uint32_t dividend, uint32_t divisor); +EXPORT_SYMBOL(__umodsi3); +int32_t __modsi3(int32_t dividend, int32_t divisor); +EXPORT_SYMBOL(__modsi3); +uint64_t __umoddi3(uint64_t dividend, uint64_t divisor); +EXPORT_SYMBOL(__umoddi3); +int64_t __moddi3(int64_t dividend, int64_t divisor); +EXPORT_SYMBOL(__moddi3); +#ifndef __tilegx__ +uint64_t __ll_mul(uint64_t n0, uint64_t n1); +EXPORT_SYMBOL(__ll_mul); +#endif +#ifndef __tilegx__ +int64_t __muldi3(int64_t, int64_t); +EXPORT_SYMBOL(__muldi3); +uint64_t __lshrdi3(uint64_t, unsigned int); +EXPORT_SYMBOL(__lshrdi3); +#endif diff --git a/arch/tile/lib/mb_incoherent.S b/arch/tile/lib/mb_incoherent.S new file mode 100644 index 0000000..989ad7b --- /dev/null +++ b/arch/tile/lib/mb_incoherent.S @@ -0,0 +1,34 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * + * Assembly code for invoking the HV's fence_incoherent syscall. + */ + +#include <linux/linkage.h> +#include <hv/syscall_public.h> +#include <arch/abi.h> +#include <arch/chip.h> + +#if !CHIP_HAS_MF_WAITS_FOR_VICTIMS() + +/* + * Invoke the hypervisor's fence_incoherent syscall, which guarantees + * that all victims for cachelines homed on this tile have reached memory. + */ +STD_ENTRY(__mb_incoherent) + moveli TREG_SYSCALL_NR_NAME, HV_SYS_fence_incoherent + swint2 + jrp lr + STD_ENDPROC(__mb_incoherent) + +#endif diff --git a/arch/tile/lib/memchr_32.c b/arch/tile/lib/memchr_32.c new file mode 100644 index 0000000..6235283 --- /dev/null +++ b/arch/tile/lib/memchr_32.c @@ -0,0 +1,68 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/types.h> +#include <linux/string.h> +#include <linux/module.h> + +void *memchr(const void *s, int c, size_t n) +{ + /* Get an aligned pointer. */ + const uintptr_t s_int = (uintptr_t) s; + const uint32_t *p = (const uint32_t *)(s_int & -4); + + /* Create four copies of the byte for which we are looking. */ + const uint32_t goal = 0x01010101 * (uint8_t) c; + + /* Read the first word, but munge it so that bytes before the array + * will not match goal. + * + * Note that this shift count expression works because we know + * shift counts are taken mod 32. + */ + const uint32_t before_mask = (1 << (s_int << 3)) - 1; + uint32_t v = (*p | before_mask) ^ (goal & before_mask); + + /* Compute the address of the last byte. */ + const char *const last_byte_ptr = (const char *)s + n - 1; + + /* Compute the address of the word containing the last byte. */ + const uint32_t *const last_word_ptr = + (const uint32_t *)((uintptr_t) last_byte_ptr & -4); + + uint32_t bits; + char *ret; + + if (__builtin_expect(n == 0, 0)) { + /* Don't dereference any memory if the array is empty. */ + return NULL; + } + + while ((bits = __insn_seqb(v, goal)) == 0) { + if (__builtin_expect(p == last_word_ptr, 0)) { + /* We already read the last word in the array, + * so give up. + */ + return NULL; + } + v = *++p; + } + + /* We found a match, but it might be in a byte past the end + * of the array. + */ + ret = ((char *)p) + (__insn_ctz(bits) >> 3); + return (ret <= last_byte_ptr) ? ret : NULL; +} +EXPORT_SYMBOL(memchr); diff --git a/arch/tile/lib/memcpy_32.S b/arch/tile/lib/memcpy_32.S new file mode 100644 index 0000000..f92984b --- /dev/null +++ b/arch/tile/lib/memcpy_32.S @@ -0,0 +1,628 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * + * This file shares the implementation of the userspace memcpy and + * the kernel's memcpy, copy_to_user and copy_from_user. + */ + +#include <arch/chip.h> + +#if CHIP_HAS_WH64() || defined(MEMCPY_TEST_WH64) +#define MEMCPY_USE_WH64 +#endif + + +#include <linux/linkage.h> + +/* On TILE64, we wrap these functions via arch/tile/lib/memcpy_tile64.c */ +#if !CHIP_HAS_COHERENT_LOCAL_CACHE() +#define memcpy __memcpy_asm +#define __copy_to_user_inatomic __copy_to_user_inatomic_asm +#define __copy_from_user_inatomic __copy_from_user_inatomic_asm +#define __copy_from_user_zeroing __copy_from_user_zeroing_asm +#endif + +#define IS_MEMCPY 0 +#define IS_COPY_FROM_USER 1 +#define IS_COPY_FROM_USER_ZEROING 2 +#define IS_COPY_TO_USER -1 + + .section .text.memcpy_common, "ax" + .align 64 + +/* Use this to preface each bundle that can cause an exception so + * the kernel can clean up properly. The special cleanup code should + * not use these, since it knows what it is doing. + */ +#define EX \ + .pushsection __ex_table, "a"; \ + .word 9f, memcpy_common_fixup; \ + .popsection; \ + 9 + + +/* __copy_from_user_inatomic takes the kernel target address in r0, + * the user source in r1, and the bytes to copy in r2. + * It returns the number of uncopiable bytes (hopefully zero) in r0. + */ +ENTRY(__copy_from_user_inatomic) +.type __copy_from_user_inatomic, @function + FEEDBACK_ENTER_EXPLICIT(__copy_from_user_inatomic, \ + .text.memcpy_common, \ + .Lend_memcpy_common - __copy_from_user_inatomic) + { movei r29, IS_COPY_FROM_USER; j memcpy_common } + .size __copy_from_user_inatomic, . - __copy_from_user_inatomic + +/* __copy_from_user_zeroing is like __copy_from_user_inatomic, but + * any uncopiable bytes are zeroed in the target. + */ +ENTRY(__copy_from_user_zeroing) +.type __copy_from_user_zeroing, @function + FEEDBACK_REENTER(__copy_from_user_inatomic) + { movei r29, IS_COPY_FROM_USER_ZEROING; j memcpy_common } + .size __copy_from_user_zeroing, . - __copy_from_user_zeroing + +/* __copy_to_user_inatomic takes the user target address in r0, + * the kernel source in r1, and the bytes to copy in r2. + * It returns the number of uncopiable bytes (hopefully zero) in r0. + */ +ENTRY(__copy_to_user_inatomic) +.type __copy_to_user_inatomic, @function + FEEDBACK_REENTER(__copy_from_user_inatomic) + { movei r29, IS_COPY_TO_USER; j memcpy_common } + .size __copy_to_user_inatomic, . - __copy_to_user_inatomic + +ENTRY(memcpy) +.type memcpy, @function + FEEDBACK_REENTER(__copy_from_user_inatomic) + { movei r29, IS_MEMCPY } + .size memcpy, . - memcpy + /* Fall through */ + + .type memcpy_common, @function +memcpy_common: + /* On entry, r29 holds one of the IS_* macro values from above. */ + + + /* r0 is the dest, r1 is the source, r2 is the size. */ + + /* Save aside original dest so we can return it at the end. */ + { sw sp, lr; move r23, r0; or r4, r0, r1 } + + /* Check for an empty size. */ + { bz r2, .Ldone; andi r4, r4, 3 } + + /* Save aside original values in case of a fault. */ + { move r24, r1; move r25, r2 } + move r27, lr + + /* Check for an unaligned source or dest. */ + { bnz r4, .Lcopy_unaligned_maybe_many; addli r4, r2, -256 } + +.Lcheck_aligned_copy_size: + /* If we are copying < 256 bytes, branch to simple case. */ + { blzt r4, .Lcopy_8_check; slti_u r8, r2, 8 } + + /* Copying >= 256 bytes, so jump to complex prefetching loop. */ + { andi r6, r1, 63; j .Lcopy_many } + +/* + * + * Aligned 4 byte at a time copy loop + * + */ + +.Lcopy_8_loop: + /* Copy two words at a time to hide load latency. */ +EX: { lw r3, r1; addi r1, r1, 4; slti_u r8, r2, 16 } +EX: { lw r4, r1; addi r1, r1, 4 } +EX: { sw r0, r3; addi r0, r0, 4; addi r2, r2, -4 } +EX: { sw r0, r4; addi r0, r0, 4; addi r2, r2, -4 } +.Lcopy_8_check: + { bzt r8, .Lcopy_8_loop; slti_u r4, r2, 4 } + + /* Copy odd leftover word, if any. */ + { bnzt r4, .Lcheck_odd_stragglers } +EX: { lw r3, r1; addi r1, r1, 4 } +EX: { sw r0, r3; addi r0, r0, 4; addi r2, r2, -4 } + +.Lcheck_odd_stragglers: + { bnz r2, .Lcopy_unaligned_few } + +.Ldone: + /* For memcpy return original dest address, else zero. */ + { mz r0, r29, r23; jrp lr } + + +/* + * + * Prefetching multiple cache line copy handler (for large transfers). + * + */ + + /* Copy words until r1 is cache-line-aligned. */ +.Lalign_loop: +EX: { lw r3, r1; addi r1, r1, 4 } + { andi r6, r1, 63 } +EX: { sw r0, r3; addi r0, r0, 4; addi r2, r2, -4 } +.Lcopy_many: + { bnzt r6, .Lalign_loop; addi r9, r0, 63 } + + { addi r3, r1, 60; andi r9, r9, -64 } + +#ifdef MEMCPY_USE_WH64 + /* No need to prefetch dst, we'll just do the wh64 + * right before we copy a line. + */ +#endif + +EX: { lw r5, r3; addi r3, r3, 64; movei r4, 1 } + /* Intentionally stall for a few cycles to leave L2 cache alone. */ + { bnzt zero, .; move r27, lr } +EX: { lw r6, r3; addi r3, r3, 64 } + /* Intentionally stall for a few cycles to leave L2 cache alone. */ + { bnzt zero, . } +EX: { lw r7, r3; addi r3, r3, 64 } +#ifndef MEMCPY_USE_WH64 + /* Prefetch the dest */ + /* Intentionally stall for a few cycles to leave L2 cache alone. */ + { bnzt zero, . } + /* Use a real load to cause a TLB miss if necessary. We aren't using + * r28, so this should be fine. + */ +EX: { lw r28, r9; addi r9, r9, 64 } + /* Intentionally stall for a few cycles to leave L2 cache alone. */ + { bnzt zero, . } + { prefetch r9; addi r9, r9, 64 } + /* Intentionally stall for a few cycles to leave L2 cache alone. */ + { bnzt zero, . } + { prefetch r9; addi r9, r9, 64 } +#endif + /* Intentionally stall for a few cycles to leave L2 cache alone. */ + { bz zero, .Lbig_loop2 } + + /* On entry to this loop: + * - r0 points to the start of dst line 0 + * - r1 points to start of src line 0 + * - r2 >= (256 - 60), only the first time the loop trips. + * - r3 contains r1 + 128 + 60 [pointer to end of source line 2] + * This is our prefetch address. When we get near the end + * rather than prefetching off the end this is changed to point + * to some "safe" recently loaded address. + * - r5 contains *(r1 + 60) [i.e. last word of source line 0] + * - r6 contains *(r1 + 64 + 60) [i.e. last word of source line 1] + * - r9 contains ((r0 + 63) & -64) + * [start of next dst cache line.] + */ + +.Lbig_loop: + { jal .Lcopy_line2; add r15, r1, r2 } + +.Lbig_loop2: + /* Copy line 0, first stalling until r5 is ready. */ +EX: { move r12, r5; lw r16, r1 } + { bz r4, .Lcopy_8_check; slti_u r8, r2, 8 } + /* Prefetch several lines ahead. */ +EX: { lw r5, r3; addi r3, r3, 64 } + { jal .Lcopy_line } + + /* Copy line 1, first stalling until r6 is ready. */ +EX: { move r12, r6; lw r16, r1 } + { bz r4, .Lcopy_8_check; slti_u r8, r2, 8 } + /* Prefetch several lines ahead. */ +EX: { lw r6, r3; addi r3, r3, 64 } + { jal .Lcopy_line } + + /* Copy line 2, first stalling until r7 is ready. */ +EX: { move r12, r7; lw r16, r1 } + { bz r4, .Lcopy_8_check; slti_u r8, r2, 8 } + /* Prefetch several lines ahead. */ +EX: { lw r7, r3; addi r3, r3, 64 } + /* Use up a caches-busy cycle by jumping back to the top of the + * loop. Might as well get it out of the way now. + */ + { j .Lbig_loop } + + + /* On entry: + * - r0 points to the destination line. + * - r1 points to the source line. + * - r3 is the next prefetch address. + * - r9 holds the last address used for wh64. + * - r12 = WORD_15 + * - r16 = WORD_0. + * - r17 == r1 + 16. + * - r27 holds saved lr to restore. + * + * On exit: + * - r0 is incremented by 64. + * - r1 is incremented by 64, unless that would point to a word + * beyond the end of the source array, in which case it is redirected + * to point to an arbitrary word already in the cache. + * - r2 is decremented by 64. + * - r3 is unchanged, unless it points to a word beyond the + * end of the source array, in which case it is redirected + * to point to an arbitrary word already in the cache. + * Redirecting is OK since if we are that close to the end + * of the array we will not come back to this subroutine + * and use the contents of the prefetched address. + * - r4 is nonzero iff r2 >= 64. + * - r9 is incremented by 64, unless it points beyond the + * end of the last full destination cache line, in which + * case it is redirected to a "safe address" that can be + * clobbered (sp - 64) + * - lr contains the value in r27. + */ + +/* r26 unused */ + +.Lcopy_line: + /* TODO: when r3 goes past the end, we would like to redirect it + * to prefetch the last partial cache line (if any) just once, for the + * benefit of the final cleanup loop. But we don't want to + * prefetch that line more than once, or subsequent prefetches + * will go into the RTF. But then .Lbig_loop should unconditionally + * branch to top of loop to execute final prefetch, and its + * nop should become a conditional branch. + */ + + /* We need two non-memory cycles here to cover the resources + * used by the loads initiated by the caller. + */ + { add r15, r1, r2 } +.Lcopy_line2: + { slt_u r13, r3, r15; addi r17, r1, 16 } + + /* NOTE: this will stall for one cycle as L1 is busy. */ + + /* Fill second L1D line. */ +EX: { lw r17, r17; addi r1, r1, 48; mvz r3, r13, r1 } /* r17 = WORD_4 */ + +#ifdef MEMCPY_TEST_WH64 + /* Issue a fake wh64 that clobbers the destination words + * with random garbage, for testing. + */ + { movei r19, 64; crc32_32 r10, r2, r9 } +.Lwh64_test_loop: +EX: { sw r9, r10; addi r9, r9, 4; addi r19, r19, -4 } + { bnzt r19, .Lwh64_test_loop; crc32_32 r10, r10, r19 } +#elif CHIP_HAS_WH64() + /* Prepare destination line for writing. */ +EX: { wh64 r9; addi r9, r9, 64 } +#else + /* Prefetch dest line */ + { prefetch r9; addi r9, r9, 64 } +#endif + /* Load seven words that are L1D hits to cover wh64 L2 usage. */ + + /* Load the three remaining words from the last L1D line, which + * we know has already filled the L1D. + */ +EX: { lw r4, r1; addi r1, r1, 4; addi r20, r1, 16 } /* r4 = WORD_12 */ +EX: { lw r8, r1; addi r1, r1, 4; slt_u r13, r20, r15 }/* r8 = WORD_13 */ +EX: { lw r11, r1; addi r1, r1, -52; mvz r20, r13, r1 } /* r11 = WORD_14 */ + + /* Load the three remaining words from the first L1D line, first + * stalling until it has filled by "looking at" r16. + */ +EX: { lw r13, r1; addi r1, r1, 4; move zero, r16 } /* r13 = WORD_1 */ +EX: { lw r14, r1; addi r1, r1, 4 } /* r14 = WORD_2 */ +EX: { lw r15, r1; addi r1, r1, 8; addi r10, r0, 60 } /* r15 = WORD_3 */ + + /* Load second word from the second L1D line, first + * stalling until it has filled by "looking at" r17. + */ +EX: { lw r19, r1; addi r1, r1, 4; move zero, r17 } /* r19 = WORD_5 */ + + /* Store last word to the destination line, potentially dirtying it + * for the first time, which keeps the L2 busy for two cycles. + */ +EX: { sw r10, r12 } /* store(WORD_15) */ + + /* Use two L1D hits to cover the sw L2 access above. */ +EX: { lw r10, r1; addi r1, r1, 4 } /* r10 = WORD_6 */ +EX: { lw r12, r1; addi r1, r1, 4 } /* r12 = WORD_7 */ + + /* Fill third L1D line. */ +EX: { lw r18, r1; addi r1, r1, 4 } /* r18 = WORD_8 */ + + /* Store first L1D line. */ +EX: { sw r0, r16; addi r0, r0, 4; add r16, r0, r2 } /* store(WORD_0) */ +EX: { sw r0, r13; addi r0, r0, 4; andi r16, r16, -64 } /* store(WORD_1) */ +EX: { sw r0, r14; addi r0, r0, 4; slt_u r16, r9, r16 } /* store(WORD_2) */ +#ifdef MEMCPY_USE_WH64 +EX: { sw r0, r15; addi r0, r0, 4; addi r13, sp, -64 } /* store(WORD_3) */ +#else + /* Back up the r9 to a cache line we are already storing to + * if it gets past the end of the dest vector. Strictly speaking, + * we don't need to back up to the start of a cache line, but it's free + * and tidy, so why not? + */ +EX: { sw r0, r15; addi r0, r0, 4; andi r13, r0, -64 } /* store(WORD_3) */ +#endif + /* Store second L1D line. */ +EX: { sw r0, r17; addi r0, r0, 4; mvz r9, r16, r13 }/* store(WORD_4) */ +EX: { sw r0, r19; addi r0, r0, 4 } /* store(WORD_5) */ +EX: { sw r0, r10; addi r0, r0, 4 } /* store(WORD_6) */ +EX: { sw r0, r12; addi r0, r0, 4 } /* store(WORD_7) */ + +EX: { lw r13, r1; addi r1, r1, 4; move zero, r18 } /* r13 = WORD_9 */ +EX: { lw r14, r1; addi r1, r1, 4 } /* r14 = WORD_10 */ +EX: { lw r15, r1; move r1, r20 } /* r15 = WORD_11 */ + + /* Store third L1D line. */ +EX: { sw r0, r18; addi r0, r0, 4 } /* store(WORD_8) */ +EX: { sw r0, r13; addi r0, r0, 4 } /* store(WORD_9) */ +EX: { sw r0, r14; addi r0, r0, 4 } /* store(WORD_10) */ +EX: { sw r0, r15; addi r0, r0, 4 } /* store(WORD_11) */ + + /* Store rest of fourth L1D line. */ +EX: { sw r0, r4; addi r0, r0, 4 } /* store(WORD_12) */ + { +EX: sw r0, r8 /* store(WORD_13) */ + addi r0, r0, 4 + /* Will r2 be > 64 after we subtract 64 below? */ + shri r4, r2, 7 + } + { +EX: sw r0, r11 /* store(WORD_14) */ + addi r0, r0, 8 + /* Record 64 bytes successfully copied. */ + addi r2, r2, -64 + } + + { jrp lr; move lr, r27 } + + /* Convey to the backtrace library that the stack frame is size + * zero, and the real return address is on the stack rather than + * in 'lr'. + */ + { info 8 } + + .align 64 +.Lcopy_unaligned_maybe_many: + /* Skip the setup overhead if we aren't copying many bytes. */ + { slti_u r8, r2, 20; sub r4, zero, r0 } + { bnzt r8, .Lcopy_unaligned_few; andi r4, r4, 3 } + { bz r4, .Ldest_is_word_aligned; add r18, r1, r2 } + +/* + * + * unaligned 4 byte at a time copy handler. + * + */ + + /* Copy single bytes until r0 == 0 mod 4, so we can store words. */ +.Lalign_dest_loop: +EX: { lb_u r3, r1; addi r1, r1, 1; addi r4, r4, -1 } +EX: { sb r0, r3; addi r0, r0, 1; addi r2, r2, -1 } + { bnzt r4, .Lalign_dest_loop; andi r3, r1, 3 } + + /* If source and dest are now *both* aligned, do an aligned copy. */ + { bz r3, .Lcheck_aligned_copy_size; addli r4, r2, -256 } + +.Ldest_is_word_aligned: + +#if CHIP_HAS_DWORD_ALIGN() +EX: { andi r8, r0, 63; lwadd_na r6, r1, 4} + { slti_u r9, r2, 64; bz r8, .Ldest_is_L2_line_aligned } + + /* This copies unaligned words until either there are fewer + * than 4 bytes left to copy, or until the destination pointer + * is cache-aligned, whichever comes first. + * + * On entry: + * - r0 is the next store address. + * - r1 points 4 bytes past the load address corresponding to r0. + * - r2 >= 4 + * - r6 is the next aligned word loaded. + */ +.Lcopy_unaligned_src_words: +EX: { lwadd_na r7, r1, 4; slti_u r8, r2, 4 + 4 } + /* stall */ + { dword_align r6, r7, r1; slti_u r9, r2, 64 + 4 } +EX: { swadd r0, r6, 4; addi r2, r2, -4 } + { bnz r8, .Lcleanup_unaligned_words; andi r8, r0, 63 } + { bnzt r8, .Lcopy_unaligned_src_words; move r6, r7 } + + /* On entry: + * - r0 is the next store address. + * - r1 points 4 bytes past the load address corresponding to r0. + * - r2 >= 4 (# of bytes left to store). + * - r6 is the next aligned src word value. + * - r9 = (r2 < 64U). + * - r18 points one byte past the end of source memory. + */ +.Ldest_is_L2_line_aligned: + + { + /* Not a full cache line remains. */ + bnz r9, .Lcleanup_unaligned_words + move r7, r6 + } + + /* r2 >= 64 */ + + /* Kick off two prefetches, but don't go past the end. */ + { addi r3, r1, 63 - 4; addi r8, r1, 64 + 63 - 4 } + { prefetch r3; move r3, r8; slt_u r8, r8, r18 } + { mvz r3, r8, r1; addi r8, r3, 64 } + { prefetch r3; move r3, r8; slt_u r8, r8, r18 } + { mvz r3, r8, r1; movei r17, 0 } + +.Lcopy_unaligned_line: + /* Prefetch another line. */ + { prefetch r3; addi r15, r1, 60; addi r3, r3, 64 } + /* Fire off a load of the last word we are about to copy. */ +EX: { lw_na r15, r15; slt_u r8, r3, r18 } + +EX: { mvz r3, r8, r1; wh64 r0 } + + /* This loop runs twice. + * + * On entry: + * - r17 is even before the first iteration, and odd before + * the second. It is incremented inside the loop. Encountering + * an even value at the end of the loop makes it stop. + */ +.Lcopy_half_an_unaligned_line: +EX: { + /* Stall until the last byte is ready. In the steady state this + * guarantees all words to load below will be in the L2 cache, which + * avoids shunting the loads to the RTF. + */ + move zero, r15 + lwadd_na r7, r1, 16 + } +EX: { lwadd_na r11, r1, 12 } +EX: { lwadd_na r14, r1, -24 } +EX: { lwadd_na r8, r1, 4 } +EX: { lwadd_na r9, r1, 4 } +EX: { + lwadd_na r10, r1, 8 + /* r16 = (r2 < 64), after we subtract 32 from r2 below. */ + slti_u r16, r2, 64 + 32 + } +EX: { lwadd_na r12, r1, 4; addi r17, r17, 1 } +EX: { lwadd_na r13, r1, 8; dword_align r6, r7, r1 } +EX: { swadd r0, r6, 4; dword_align r7, r8, r1 } +EX: { swadd r0, r7, 4; dword_align r8, r9, r1 } +EX: { swadd r0, r8, 4; dword_align r9, r10, r1 } +EX: { swadd r0, r9, 4; dword_align r10, r11, r1 } +EX: { swadd r0, r10, 4; dword_align r11, r12, r1 } +EX: { swadd r0, r11, 4; dword_align r12, r13, r1 } +EX: { swadd r0, r12, 4; dword_align r13, r14, r1 } +EX: { swadd r0, r13, 4; addi r2, r2, -32 } + { move r6, r14; bbst r17, .Lcopy_half_an_unaligned_line } + + { bzt r16, .Lcopy_unaligned_line; move r7, r6 } + + /* On entry: + * - r0 is the next store address. + * - r1 points 4 bytes past the load address corresponding to r0. + * - r2 >= 0 (# of bytes left to store). + * - r7 is the next aligned src word value. + */ +.Lcleanup_unaligned_words: + /* Handle any trailing bytes. */ + { bz r2, .Lcopy_unaligned_done; slti_u r8, r2, 4 } + { bzt r8, .Lcopy_unaligned_src_words; move r6, r7 } + + /* Move r1 back to the point where it corresponds to r0. */ + { addi r1, r1, -4 } + +#else /* !CHIP_HAS_DWORD_ALIGN() */ + + /* Compute right/left shift counts and load initial source words. */ + { andi r5, r1, -4; andi r3, r1, 3 } +EX: { lw r6, r5; addi r5, r5, 4; shli r3, r3, 3 } +EX: { lw r7, r5; addi r5, r5, 4; sub r4, zero, r3 } + + /* Load and store one word at a time, using shifts and ORs + * to correct for the misaligned src. + */ +.Lcopy_unaligned_src_loop: + { shr r6, r6, r3; shl r8, r7, r4 } +EX: { lw r7, r5; or r8, r8, r6; move r6, r7 } +EX: { sw r0, r8; addi r0, r0, 4; addi r2, r2, -4 } + { addi r5, r5, 4; slti_u r8, r2, 8 } + { bzt r8, .Lcopy_unaligned_src_loop; addi r1, r1, 4 } + + { bz r2, .Lcopy_unaligned_done } +#endif /* !CHIP_HAS_DWORD_ALIGN() */ + + /* Fall through */ + +/* + * + * 1 byte at a time copy handler. + * + */ + +.Lcopy_unaligned_few: +EX: { lb_u r3, r1; addi r1, r1, 1 } +EX: { sb r0, r3; addi r0, r0, 1; addi r2, r2, -1 } + { bnzt r2, .Lcopy_unaligned_few } + +.Lcopy_unaligned_done: + + /* For memcpy return original dest address, else zero. */ + { mz r0, r29, r23; jrp lr } + +.Lend_memcpy_common: + .size memcpy_common, .Lend_memcpy_common - memcpy_common + + .section .fixup,"ax" +memcpy_common_fixup: + .type memcpy_common_fixup, @function + + /* Skip any bytes we already successfully copied. + * r2 (num remaining) is correct, but r0 (dst) and r1 (src) + * may not be quite right because of unrolling and prefetching. + * So we need to recompute their values as the address just + * after the last byte we are sure was successfully loaded and + * then stored. + */ + + /* Determine how many bytes we successfully copied. */ + { sub r3, r25, r2 } + + /* Add this to the original r0 and r1 to get their new values. */ + { add r0, r23, r3; add r1, r24, r3 } + + { bzt r29, memcpy_fixup_loop } + { blzt r29, copy_to_user_fixup_loop } + +copy_from_user_fixup_loop: + /* Try copying the rest one byte at a time, expecting a load fault. */ +.Lcfu: { lb_u r3, r1; addi r1, r1, 1 } + { sb r0, r3; addi r0, r0, 1; addi r2, r2, -1 } + { bnzt r2, copy_from_user_fixup_loop } + +.Lcopy_from_user_fixup_zero_remainder: + { bbs r29, 2f } /* low bit set means IS_COPY_FROM_USER */ + /* byte-at-a-time loop faulted, so zero the rest. */ + { move r3, r2; bz r2, 2f /* should be impossible, but handle it. */ } +1: { sb r0, zero; addi r0, r0, 1; addi r3, r3, -1 } + { bnzt r3, 1b } +2: move lr, r27 + { move r0, r2; jrp lr } + +copy_to_user_fixup_loop: + /* Try copying the rest one byte at a time, expecting a store fault. */ + { lb_u r3, r1; addi r1, r1, 1 } +.Lctu: { sb r0, r3; addi r0, r0, 1; addi r2, r2, -1 } + { bnzt r2, copy_to_user_fixup_loop } +.Lcopy_to_user_fixup_done: + move lr, r27 + { move r0, r2; jrp lr } + +memcpy_fixup_loop: + /* Try copying the rest one byte at a time. We expect a disastrous + * fault to happen since we are in fixup code, but let it happen. + */ + { lb_u r3, r1; addi r1, r1, 1 } + { sb r0, r3; addi r0, r0, 1; addi r2, r2, -1 } + { bnzt r2, memcpy_fixup_loop } + /* This should be unreachable, we should have faulted again. + * But be paranoid and handle it in case some interrupt changed + * the TLB or something. + */ + move lr, r27 + { move r0, r23; jrp lr } + + .size memcpy_common_fixup, . - memcpy_common_fixup + + .section __ex_table,"a" + .word .Lcfu, .Lcopy_from_user_fixup_zero_remainder + .word .Lctu, .Lcopy_to_user_fixup_done diff --git a/arch/tile/lib/memcpy_tile64.c b/arch/tile/lib/memcpy_tile64.c new file mode 100644 index 0000000..4f00473 --- /dev/null +++ b/arch/tile/lib/memcpy_tile64.c @@ -0,0 +1,271 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/string.h> +#include <linux/smp.h> +#include <linux/module.h> +#include <linux/uaccess.h> +#include <asm/fixmap.h> +#include <asm/kmap_types.h> +#include <asm/tlbflush.h> +#include <hv/hypervisor.h> +#include <arch/chip.h> + + +#if !CHIP_HAS_COHERENT_LOCAL_CACHE() + +/* Defined in memcpy.S */ +extern unsigned long __memcpy_asm(void *to, const void *from, unsigned long n); +extern unsigned long __copy_to_user_inatomic_asm( + void __user *to, const void *from, unsigned long n); +extern unsigned long __copy_from_user_inatomic_asm( + void *to, const void __user *from, unsigned long n); +extern unsigned long __copy_from_user_zeroing_asm( + void *to, const void __user *from, unsigned long n); + +typedef unsigned long (*memcpy_t)(void *, const void *, unsigned long); + +/* Size above which to consider TLB games for performance */ +#define LARGE_COPY_CUTOFF 2048 + +/* Communicate to the simulator what we are trying to do. */ +#define sim_allow_multiple_caching(b) \ + __insn_mtspr(SPR_SIM_CONTROL, \ + SIM_CONTROL_ALLOW_MULTIPLE_CACHING | ((b) << _SIM_CONTROL_OPERATOR_BITS)) + +/* + * Copy memory by briefly enabling incoherent cacheline-at-a-time mode. + * + * We set up our own source and destination PTEs that we fully control. + * This is the only way to guarantee that we don't race with another + * thread that is modifying the PTE; we can't afford to try the + * copy_{to,from}_user() technique of catching the interrupt, since + * we must run with interrupts disabled to avoid the risk of some + * other code seeing the incoherent data in our cache. (Recall that + * our cache is indexed by PA, so even if the other code doesn't use + * our KM_MEMCPY virtual addresses, they'll still hit in cache using + * the normal VAs that aren't supposed to hit in cache.) + */ +static void memcpy_multicache(void *dest, const void *source, + pte_t dst_pte, pte_t src_pte, int len) +{ + int idx, i; + unsigned long flags, newsrc, newdst, endsrc; + pmd_t *pmdp; + pte_t *ptep; + int cpu = get_cpu(); + + /* + * Disable interrupts so that we don't recurse into memcpy() + * in an interrupt handler, nor accidentally reference + * the PA of the source from an interrupt routine. Also + * notify the simulator that we're playing games so we don't + * generate spurious coherency warnings. + */ + local_irq_save(flags); + sim_allow_multiple_caching(1); + + /* Set up the new dest mapping */ + idx = FIX_KMAP_BEGIN + (KM_TYPE_NR * cpu) + KM_MEMCPY0; + newdst = __fix_to_virt(idx) + ((unsigned long)dest & (PAGE_SIZE-1)); + pmdp = pmd_offset(pud_offset(pgd_offset_k(newdst), newdst), newdst); + ptep = pte_offset_kernel(pmdp, newdst); + if (pte_val(*ptep) != pte_val(dst_pte)) { + set_pte(ptep, dst_pte); + local_flush_tlb_page(NULL, newdst, PAGE_SIZE); + } + + /* Set up the new source mapping */ + idx += (KM_MEMCPY0 - KM_MEMCPY1); + src_pte = hv_pte_set_nc(src_pte); + src_pte = hv_pte_clear_writable(src_pte); /* be paranoid */ + newsrc = __fix_to_virt(idx) + ((unsigned long)source & (PAGE_SIZE-1)); + pmdp = pmd_offset(pud_offset(pgd_offset_k(newsrc), newsrc), newsrc); + ptep = pte_offset_kernel(pmdp, newsrc); + *ptep = src_pte; /* set_pte() would be confused by this */ + local_flush_tlb_page(NULL, newsrc, PAGE_SIZE); + + /* Actually move the data. */ + __memcpy_asm((void *)newdst, (const void *)newsrc, len); + + /* + * Remap the source as locally-cached and not OLOC'ed so that + * we can inval without also invaling the remote cpu's cache. + * This also avoids known errata with inv'ing cacheable oloc data. + */ + src_pte = hv_pte_set_mode(src_pte, HV_PTE_MODE_CACHE_NO_L3); + src_pte = hv_pte_set_writable(src_pte); /* need write access for inv */ + *ptep = src_pte; /* set_pte() would be confused by this */ + local_flush_tlb_page(NULL, newsrc, PAGE_SIZE); + + /* + * Do the actual invalidation, covering the full L2 cache line + * at the end since __memcpy_asm() is somewhat aggressive. + */ + __inv_buffer((void *)newsrc, len); + + /* + * We're done: notify the simulator that all is back to normal, + * and re-enable interrupts and pre-emption. + */ + sim_allow_multiple_caching(0); + local_irq_restore(flags); + put_cpu_no_resched(); +} + +/* + * Identify large copies from remotely-cached memory, and copy them + * via memcpy_multicache() if they look good, otherwise fall back + * to the particular kind of copying passed as the memcpy_t function. + */ +static unsigned long fast_copy(void *dest, const void *source, int len, + memcpy_t func) +{ + /* + * Check if it's big enough to bother with. We may end up doing a + * small copy via TLB manipulation if we're near a page boundary, + * but presumably we'll make it up when we hit the second page. + */ + while (len >= LARGE_COPY_CUTOFF) { + int copy_size, bytes_left_on_page; + pte_t *src_ptep, *dst_ptep; + pte_t src_pte, dst_pte; + struct page *src_page, *dst_page; + + /* Is the source page oloc'ed to a remote cpu? */ +retry_source: + src_ptep = virt_to_pte(current->mm, (unsigned long)source); + if (src_ptep == NULL) + break; + src_pte = *src_ptep; + if (!hv_pte_get_present(src_pte) || + !hv_pte_get_readable(src_pte) || + hv_pte_get_mode(src_pte) != HV_PTE_MODE_CACHE_TILE_L3) + break; + if (get_remote_cache_cpu(src_pte) == smp_processor_id()) + break; + src_page = pfn_to_page(hv_pte_get_pfn(src_pte)); + get_page(src_page); + if (pte_val(src_pte) != pte_val(*src_ptep)) { + put_page(src_page); + goto retry_source; + } + if (pte_huge(src_pte)) { + /* Adjust the PTE to correspond to a small page */ + int pfn = hv_pte_get_pfn(src_pte); + pfn += (((unsigned long)source & (HPAGE_SIZE-1)) + >> PAGE_SHIFT); + src_pte = pfn_pte(pfn, src_pte); + src_pte = pte_mksmall(src_pte); + } + + /* Is the destination page writable? */ +retry_dest: + dst_ptep = virt_to_pte(current->mm, (unsigned long)dest); + if (dst_ptep == NULL) { + put_page(src_page); + break; + } + dst_pte = *dst_ptep; + if (!hv_pte_get_present(dst_pte) || + !hv_pte_get_writable(dst_pte)) { + put_page(src_page); + break; + } + dst_page = pfn_to_page(hv_pte_get_pfn(dst_pte)); + if (dst_page == src_page) { + /* + * Source and dest are on the same page; this + * potentially exposes us to incoherence if any + * part of src and dest overlap on a cache line. + * Just give up rather than trying to be precise. + */ + put_page(src_page); + break; + } + get_page(dst_page); + if (pte_val(dst_pte) != pte_val(*dst_ptep)) { + put_page(dst_page); + goto retry_dest; + } + if (pte_huge(dst_pte)) { + /* Adjust the PTE to correspond to a small page */ + int pfn = hv_pte_get_pfn(dst_pte); + pfn += (((unsigned long)dest & (HPAGE_SIZE-1)) + >> PAGE_SHIFT); + dst_pte = pfn_pte(pfn, dst_pte); + dst_pte = pte_mksmall(dst_pte); + } + + /* All looks good: create a cachable PTE and copy from it */ + copy_size = len; + bytes_left_on_page = + PAGE_SIZE - (((int)source) & (PAGE_SIZE-1)); + if (copy_size > bytes_left_on_page) + copy_size = bytes_left_on_page; + bytes_left_on_page = + PAGE_SIZE - (((int)dest) & (PAGE_SIZE-1)); + if (copy_size > bytes_left_on_page) + copy_size = bytes_left_on_page; + memcpy_multicache(dest, source, dst_pte, src_pte, copy_size); + + /* Release the pages */ + put_page(dst_page); + put_page(src_page); + + /* Continue on the next page */ + dest += copy_size; + source += copy_size; + len -= copy_size; + } + + return func(dest, source, len); +} + +void *memcpy(void *to, const void *from, __kernel_size_t n) +{ + if (n < LARGE_COPY_CUTOFF) + return (void *)__memcpy_asm(to, from, n); + else + return (void *)fast_copy(to, from, n, __memcpy_asm); +} + +unsigned long __copy_to_user_inatomic(void __user *to, const void *from, + unsigned long n) +{ + if (n < LARGE_COPY_CUTOFF) + return __copy_to_user_inatomic_asm(to, from, n); + else + return fast_copy(to, from, n, __copy_to_user_inatomic_asm); +} + +unsigned long __copy_from_user_inatomic(void *to, const void __user *from, + unsigned long n) +{ + if (n < LARGE_COPY_CUTOFF) + return __copy_from_user_inatomic_asm(to, from, n); + else + return fast_copy(to, from, n, __copy_from_user_inatomic_asm); +} + +unsigned long __copy_from_user_zeroing(void *to, const void __user *from, + unsigned long n) +{ + if (n < LARGE_COPY_CUTOFF) + return __copy_from_user_zeroing_asm(to, from, n); + else + return fast_copy(to, from, n, __copy_from_user_zeroing_asm); +} + +#endif /* !CHIP_HAS_COHERENT_LOCAL_CACHE() */ diff --git a/arch/tile/lib/memmove_32.c b/arch/tile/lib/memmove_32.c new file mode 100644 index 0000000..f09d8c4 --- /dev/null +++ b/arch/tile/lib/memmove_32.c @@ -0,0 +1,63 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/types.h> +#include <linux/string.h> +#include <linux/module.h> + +void *memmove(void *dest, const void *src, size_t n) +{ + if ((const char *)src >= (char *)dest + n + || (char *)dest >= (const char *)src + n) { + /* We found no overlap, so let memcpy do all the heavy + * lifting (prefetching, etc.) + */ + return memcpy(dest, src, n); + } + + if (n != 0) { + const uint8_t *in; + uint8_t x; + uint8_t *out; + int stride; + + if (src < dest) { + /* copy backwards */ + in = (const uint8_t *)src + n - 1; + out = (uint8_t *)dest + n - 1; + stride = -1; + } else { + /* copy forwards */ + in = (const uint8_t *)src; + out = (uint8_t *)dest; + stride = 1; + } + + /* Manually software-pipeline this loop. */ + x = *in; + in += stride; + + while (--n != 0) { + *out = x; + out += stride; + x = *in; + in += stride; + } + + *out = x; + } + + return dest; +} +EXPORT_SYMBOL(memmove); diff --git a/arch/tile/lib/memset_32.c b/arch/tile/lib/memset_32.c new file mode 100644 index 0000000..8593bc82 --- /dev/null +++ b/arch/tile/lib/memset_32.c @@ -0,0 +1,274 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <arch/chip.h> + +#include <linux/types.h> +#include <linux/string.h> +#include <linux/module.h> + + +void *memset(void *s, int c, size_t n) +{ + uint32_t *out32; + int n32; + uint32_t v16, v32; + uint8_t *out8 = s; +#if !CHIP_HAS_WH64() + int ahead32; +#else + int to_align32; +#endif + + /* Experimentation shows that a trivial tight loop is a win up until + * around a size of 20, where writing a word at a time starts to win. + */ +#define BYTE_CUTOFF 20 + +#if BYTE_CUTOFF < 3 + /* This must be at least at least this big, or some code later + * on doesn't work. + */ +#error "BYTE_CUTOFF is too small" +#endif + + if (n < BYTE_CUTOFF) { + /* Strangely, this turns out to be the tightest way to + * write this loop. + */ + if (n != 0) { + do { + /* Strangely, combining these into one line + * performs worse. + */ + *out8 = c; + out8++; + } while (--n != 0); + } + + return s; + } + +#if !CHIP_HAS_WH64() + /* Use a spare issue slot to start prefetching the first cache + * line early. This instruction is free as the store can be buried + * in otherwise idle issue slots doing ALU ops. + */ + __insn_prefetch(out8); + + /* We prefetch the end so that a short memset that spans two cache + * lines gets some prefetching benefit. Again we believe this is free + * to issue. + */ + __insn_prefetch(&out8[n - 1]); +#endif /* !CHIP_HAS_WH64() */ + + + /* Align 'out8'. We know n >= 3 so this won't write past the end. */ + while (((uintptr_t) out8 & 3) != 0) { + *out8++ = c; + --n; + } + + /* Align 'n'. */ + while (n & 3) + out8[--n] = c; + + out32 = (uint32_t *) out8; + n32 = n >> 2; + + /* Tile input byte out to 32 bits. */ + v16 = __insn_intlb(c, c); + v32 = __insn_intlh(v16, v16); + + /* This must be at least 8 or the following loop doesn't work. */ +#define CACHE_LINE_SIZE_IN_WORDS (CHIP_L2_LINE_SIZE() / 4) + +#if !CHIP_HAS_WH64() + + ahead32 = CACHE_LINE_SIZE_IN_WORDS; + + /* We already prefetched the first and last cache lines, so + * we only need to do more prefetching if we are storing + * to more than two cache lines. + */ + if (n32 > CACHE_LINE_SIZE_IN_WORDS * 2) { + int i; + + /* Prefetch the next several cache lines. + * This is the setup code for the software-pipelined + * loop below. + */ +#define MAX_PREFETCH 5 + ahead32 = n32 & -CACHE_LINE_SIZE_IN_WORDS; + if (ahead32 > MAX_PREFETCH * CACHE_LINE_SIZE_IN_WORDS) + ahead32 = MAX_PREFETCH * CACHE_LINE_SIZE_IN_WORDS; + + for (i = CACHE_LINE_SIZE_IN_WORDS; + i < ahead32; i += CACHE_LINE_SIZE_IN_WORDS) + __insn_prefetch(&out32[i]); + } + + if (n32 > ahead32) { + while (1) { + int j; + + /* Prefetch by reading one word several cache lines + * ahead. Since loads are non-blocking this will + * cause the full cache line to be read while we are + * finishing earlier cache lines. Using a store + * here causes microarchitectural performance + * problems where a victimizing store miss goes to + * the head of the retry FIFO and locks the pipe for + * a few cycles. So a few subsequent stores in this + * loop go into the retry FIFO, and then later + * stores see other stores to the same cache line + * are already in the retry FIFO and themselves go + * into the retry FIFO, filling it up and grinding + * to a halt waiting for the original miss to be + * satisfied. + */ + __insn_prefetch(&out32[ahead32]); + +#if 1 +#if CACHE_LINE_SIZE_IN_WORDS % 4 != 0 +#error "Unhandled CACHE_LINE_SIZE_IN_WORDS" +#endif + + n32 -= CACHE_LINE_SIZE_IN_WORDS; + + /* Save icache space by only partially unrolling + * this loop. + */ + for (j = CACHE_LINE_SIZE_IN_WORDS / 4; j > 0; j--) { + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + } +#else + /* Unfortunately, due to a code generator flaw this + * allocates a separate register for each of these + * stores, which requires a large number of spills, + * which makes this procedure enormously bigger + * (something like 70%) + */ + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + n32 -= 16; +#endif + + /* To save compiled code size, reuse this loop even + * when we run out of prefetching to do by dropping + * ahead32 down. + */ + if (n32 <= ahead32) { + /* Not even a full cache line left, + * so stop now. + */ + if (n32 < CACHE_LINE_SIZE_IN_WORDS) + break; + + /* Choose a small enough value that we don't + * prefetch past the end. There's no sense + * in touching cache lines we don't have to. + */ + ahead32 = CACHE_LINE_SIZE_IN_WORDS - 1; + } + } + } + +#else /* CHIP_HAS_WH64() */ + + /* Determine how many words we need to emit before the 'out32' + * pointer becomes aligned modulo the cache line size. + */ + to_align32 = + (-((uintptr_t)out32 >> 2)) & (CACHE_LINE_SIZE_IN_WORDS - 1); + + /* Only bother aligning and using wh64 if there is at least + * one full cache line to process. This check also prevents + * overrunning the end of the buffer with alignment words. + */ + if (to_align32 <= n32 - CACHE_LINE_SIZE_IN_WORDS) { + int lines_left; + + /* Align out32 mod the cache line size so we can use wh64. */ + n32 -= to_align32; + for (; to_align32 != 0; to_align32--) { + *out32 = v32; + out32++; + } + + /* Use unsigned divide to turn this into a right shift. */ + lines_left = (unsigned)n32 / CACHE_LINE_SIZE_IN_WORDS; + + do { + /* Only wh64 a few lines at a time, so we don't + * exceed the maximum number of victim lines. + */ + int x = ((lines_left < CHIP_MAX_OUTSTANDING_VICTIMS()) + ? lines_left + : CHIP_MAX_OUTSTANDING_VICTIMS()); + uint32_t *wh = out32; + int i = x; + int j; + + lines_left -= x; + + do { + __insn_wh64(wh); + wh += CACHE_LINE_SIZE_IN_WORDS; + } while (--i); + + for (j = x * (CACHE_LINE_SIZE_IN_WORDS / 4); j != 0; j--) { + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + } + } while (lines_left != 0); + + /* We processed all full lines above, so only this many + * words remain to be processed. + */ + n32 &= CACHE_LINE_SIZE_IN_WORDS - 1; + } + +#endif /* CHIP_HAS_WH64() */ + + /* Now handle any leftover values. */ + if (n32 != 0) { + do { + *out32 = v32; + out32++; + } while (--n32 != 0); + } + + return s; +} +EXPORT_SYMBOL(memset); diff --git a/arch/tile/lib/spinlock_32.c b/arch/tile/lib/spinlock_32.c new file mode 100644 index 0000000..485e24d --- /dev/null +++ b/arch/tile/lib/spinlock_32.c @@ -0,0 +1,221 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/spinlock.h> +#include <linux/module.h> +#include <asm/processor.h> + +#include "spinlock_common.h" + +void arch_spin_lock(arch_spinlock_t *lock) +{ + int my_ticket; + int iterations = 0; + int delta; + + while ((my_ticket = __insn_tns((void *)&lock->next_ticket)) & 1) + delay_backoff(iterations++); + + /* Increment the next ticket number, implicitly releasing tns lock. */ + lock->next_ticket = my_ticket + TICKET_QUANTUM; + + /* Wait until it's our turn. */ + while ((delta = my_ticket - lock->current_ticket) != 0) + relax((128 / CYCLES_PER_RELAX_LOOP) * delta); +} +EXPORT_SYMBOL(arch_spin_lock); + +int arch_spin_trylock(arch_spinlock_t *lock) +{ + /* + * Grab a ticket; no need to retry if it's busy, we'll just + * treat that the same as "locked", since someone else + * will lock it momentarily anyway. + */ + int my_ticket = __insn_tns((void *)&lock->next_ticket); + + if (my_ticket == lock->current_ticket) { + /* Not currently locked, so lock it by keeping this ticket. */ + lock->next_ticket = my_ticket + TICKET_QUANTUM; + /* Success! */ + return 1; + } + + if (!(my_ticket & 1)) { + /* Release next_ticket. */ + lock->next_ticket = my_ticket; + } + + return 0; +} +EXPORT_SYMBOL(arch_spin_trylock); + +void arch_spin_unlock_wait(arch_spinlock_t *lock) +{ + u32 iterations = 0; + while (arch_spin_is_locked(lock)) + delay_backoff(iterations++); +} +EXPORT_SYMBOL(arch_spin_unlock_wait); + +/* + * The low byte is always reserved to be the marker for a "tns" operation + * since the low bit is set to "1" by a tns. The next seven bits are + * zeroes. The next byte holds the "next" writer value, i.e. the ticket + * available for the next task that wants to write. The third byte holds + * the current writer value, i.e. the writer who holds the current ticket. + * If current == next == 0, there are no interested writers. + */ +#define WR_NEXT_SHIFT _WR_NEXT_SHIFT +#define WR_CURR_SHIFT _WR_CURR_SHIFT +#define WR_WIDTH _WR_WIDTH +#define WR_MASK ((1 << WR_WIDTH) - 1) + +/* + * The last eight bits hold the active reader count. This has to be + * zero before a writer can start to write. + */ +#define RD_COUNT_SHIFT _RD_COUNT_SHIFT +#define RD_COUNT_WIDTH _RD_COUNT_WIDTH +#define RD_COUNT_MASK ((1 << RD_COUNT_WIDTH) - 1) + + +/* Lock the word, spinning until there are no tns-ers. */ +static inline u32 get_rwlock(arch_rwlock_t *rwlock) +{ + u32 iterations = 0; + for (;;) { + u32 val = __insn_tns((int *)&rwlock->lock); + if (unlikely(val & 1)) { + delay_backoff(iterations++); + continue; + } + return val; + } +} + +int arch_read_trylock_slow(arch_rwlock_t *rwlock) +{ + u32 val = get_rwlock(rwlock); + int locked = (val << RD_COUNT_WIDTH) == 0; + rwlock->lock = val + (locked << RD_COUNT_SHIFT); + return locked; +} +EXPORT_SYMBOL(arch_read_trylock_slow); + +void arch_read_unlock_slow(arch_rwlock_t *rwlock) +{ + u32 val = get_rwlock(rwlock); + rwlock->lock = val - (1 << RD_COUNT_SHIFT); +} +EXPORT_SYMBOL(arch_read_unlock_slow); + +void arch_write_unlock_slow(arch_rwlock_t *rwlock, u32 val) +{ + u32 eq, mask = 1 << WR_CURR_SHIFT; + while (unlikely(val & 1)) { + /* Limited backoff since we are the highest-priority task. */ + relax(4); + val = __insn_tns((int *)&rwlock->lock); + } + val = __insn_addb(val, mask); + eq = __insn_seqb(val, val << (WR_CURR_SHIFT - WR_NEXT_SHIFT)); + val = __insn_mz(eq & mask, val); + rwlock->lock = val; +} +EXPORT_SYMBOL(arch_write_unlock_slow); + +/* + * We spin until everything but the reader bits (which are in the high + * part of the word) are zero, i.e. no active or waiting writers, no tns. + * + * ISSUE: This approach can permanently starve readers. A reader who sees + * a writer could instead take a ticket lock (just like a writer would), + * and atomically enter read mode (with 1 reader) when it gets the ticket. + * This way both readers and writers will always make forward progress + * in a finite time. + */ +void arch_read_lock_slow(arch_rwlock_t *rwlock, u32 val) +{ + u32 iterations = 0; + do { + if (!(val & 1)) + rwlock->lock = val; + delay_backoff(iterations++); + val = __insn_tns((int *)&rwlock->lock); + } while ((val << RD_COUNT_WIDTH) != 0); + rwlock->lock = val + (1 << RD_COUNT_SHIFT); +} +EXPORT_SYMBOL(arch_read_lock_slow); + +void arch_write_lock_slow(arch_rwlock_t *rwlock, u32 val) +{ + /* + * The trailing underscore on this variable (and curr_ below) + * reminds us that the high bits are garbage; we mask them out + * when we compare them. + */ + u32 my_ticket_; + + /* Take out the next ticket; this will also stop would-be readers. */ + if (val & 1) + val = get_rwlock(rwlock); + rwlock->lock = __insn_addb(val, 1 << WR_NEXT_SHIFT); + + /* Extract my ticket value from the original word. */ + my_ticket_ = val >> WR_NEXT_SHIFT; + + /* + * Wait until the "current" field matches our ticket, and + * there are no remaining readers. + */ + for (;;) { + u32 curr_ = val >> WR_CURR_SHIFT; + u32 readers = val >> RD_COUNT_SHIFT; + u32 delta = ((my_ticket_ - curr_) & WR_MASK) + !!readers; + if (likely(delta == 0)) + break; + + /* Delay based on how many lock-holders are still out there. */ + relax((256 / CYCLES_PER_RELAX_LOOP) * delta); + + /* + * Get a non-tns value to check; we don't need to tns + * it ourselves. Since we're not tns'ing, we retry + * more rapidly to get a valid value. + */ + while ((val = rwlock->lock) & 1) + relax(4); + } +} +EXPORT_SYMBOL(arch_write_lock_slow); + +int __tns_atomic_acquire(atomic_t *lock) +{ + int ret; + u32 iterations = 0; + + BUG_ON(__insn_mfspr(SPR_INTERRUPT_CRITICAL_SECTION)); + __insn_mtspr(SPR_INTERRUPT_CRITICAL_SECTION, 1); + + while ((ret = __insn_tns((void *)&lock->counter)) == 1) + delay_backoff(iterations++); + return ret; +} + +void __tns_atomic_release(atomic_t *p, int v) +{ + p->counter = v; + __insn_mtspr(SPR_INTERRUPT_CRITICAL_SECTION, 0); +} diff --git a/arch/tile/lib/spinlock_common.h b/arch/tile/lib/spinlock_common.h new file mode 100644 index 0000000..8dffebd --- /dev/null +++ b/arch/tile/lib/spinlock_common.h @@ -0,0 +1,64 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * This file is included into spinlock_32.c or _64.c. + */ + +/* + * The mfspr in __spinlock_relax() is 5 or 6 cycles plus 2 for loop + * overhead. + */ +#ifdef __tilegx__ +#define CYCLES_PER_RELAX_LOOP 7 +#else +#define CYCLES_PER_RELAX_LOOP 8 +#endif + +/* + * Idle the core for CYCLES_PER_RELAX_LOOP * iterations cycles. + */ +static inline void +relax(int iterations) +{ + for (/*above*/; iterations > 0; iterations--) + __insn_mfspr(SPR_PASS); + barrier(); +} + +/* Perform bounded exponential backoff.*/ +void delay_backoff(int iterations) +{ + u32 exponent, loops; + + /* + * 2^exponent is how many times we go around the loop, + * which takes 8 cycles. We want to start with a 16- to 31-cycle + * loop, so we need to go around minimum 2 = 2^1 times, so we + * bias the original value up by 1. + */ + exponent = iterations + 1; + + /* + * Don't allow exponent to exceed 7, so we have 128 loops, + * or 1,024 (to 2,047) cycles, as our maximum. + */ + if (exponent > 8) + exponent = 8; + + loops = 1 << exponent; + + /* Add a randomness factor so two cpus never get in lock step. */ + loops += __insn_crc32_32(stack_pointer, get_cycles_low()) & + (loops - 1); + + relax(1 << exponent); +} diff --git a/arch/tile/lib/strchr_32.c b/arch/tile/lib/strchr_32.c new file mode 100644 index 0000000..c94e6f7 --- /dev/null +++ b/arch/tile/lib/strchr_32.c @@ -0,0 +1,66 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/types.h> +#include <linux/string.h> +#include <linux/module.h> + +#undef strchr + +char *strchr(const char *s, int c) +{ + int z, g; + + /* Get an aligned pointer. */ + const uintptr_t s_int = (uintptr_t) s; + const uint32_t *p = (const uint32_t *)(s_int & -4); + + /* Create four copies of the byte for which we are looking. */ + const uint32_t goal = 0x01010101 * (uint8_t) c; + + /* Read the first aligned word, but force bytes before the string to + * match neither zero nor goal (we make sure the high bit of each + * byte is 1, and the low 7 bits are all the opposite of the goal + * byte). + * + * Note that this shift count expression works because we know shift + * counts are taken mod 32. + */ + const uint32_t before_mask = (1 << (s_int << 3)) - 1; + uint32_t v = (*p | before_mask) ^ (goal & __insn_shrib(before_mask, 1)); + + uint32_t zero_matches, goal_matches; + while (1) { + /* Look for a terminating '\0'. */ + zero_matches = __insn_seqb(v, 0); + + /* Look for the goal byte. */ + goal_matches = __insn_seqb(v, goal); + + if (__builtin_expect(zero_matches | goal_matches, 0)) + break; + + v = *++p; + } + + z = __insn_ctz(zero_matches); + g = __insn_ctz(goal_matches); + + /* If we found c before '\0' we got a match. Note that if c == '\0' + * then g == z, and we correctly return the address of the '\0' + * rather than NULL. + */ + return (g <= z) ? ((char *)p) + (g >> 3) : NULL; +} +EXPORT_SYMBOL(strchr); diff --git a/arch/tile/lib/strlen_32.c b/arch/tile/lib/strlen_32.c new file mode 100644 index 0000000..f26f88e --- /dev/null +++ b/arch/tile/lib/strlen_32.c @@ -0,0 +1,36 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/types.h> +#include <linux/string.h> +#include <linux/module.h> + +size_t strlen(const char *s) +{ + /* Get an aligned pointer. */ + const uintptr_t s_int = (uintptr_t) s; + const uint32_t *p = (const uint32_t *)(s_int & -4); + + /* Read the first word, but force bytes before the string to be nonzero. + * This expression works because we know shift counts are taken mod 32. + */ + uint32_t v = *p | ((1 << (s_int << 3)) - 1); + + uint32_t bits; + while ((bits = __insn_seqb(v, 0)) == 0) + v = *++p; + + return ((const char *)p) + (__insn_ctz(bits) >> 3) - s; +} +EXPORT_SYMBOL(strlen); diff --git a/arch/tile/lib/uaccess.c b/arch/tile/lib/uaccess.c new file mode 100644 index 0000000..9ae1825 --- /dev/null +++ b/arch/tile/lib/uaccess.c @@ -0,0 +1,31 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/uaccess.h> +#include <linux/module.h> + +int __range_ok(unsigned long addr, unsigned long size) +{ + unsigned long limit = current_thread_info()->addr_limit.seg; + __chk_user_ptr(addr); + return !((addr < limit && size <= limit - addr) || + is_arch_mappable_range(addr, size)); +} +EXPORT_SYMBOL(__range_ok); + +void copy_from_user_overflow(void) +{ + WARN(1, "Buffer overflow detected!\n"); +} +EXPORT_SYMBOL(copy_from_user_overflow); diff --git a/arch/tile/lib/usercopy_32.S b/arch/tile/lib/usercopy_32.S new file mode 100644 index 0000000..979f76d --- /dev/null +++ b/arch/tile/lib/usercopy_32.S @@ -0,0 +1,223 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/linkage.h> +#include <asm/errno.h> +#include <asm/cache.h> +#include <arch/chip.h> + +/* Access user memory, but use MMU to avoid propagating kernel exceptions. */ + + .pushsection .fixup,"ax" + +get_user_fault: + { move r0, zero; move r1, zero } + { movei r2, -EFAULT; jrp lr } + ENDPROC(get_user_fault) + +put_user_fault: + { movei r0, -EFAULT; jrp lr } + ENDPROC(put_user_fault) + + .popsection + +/* + * __get_user_N functions take a pointer in r0, and return 0 in r2 + * on success, with the value in r0; or else -EFAULT in r2. + */ +#define __get_user_N(bytes, LOAD) \ + STD_ENTRY(__get_user_##bytes); \ +1: { LOAD r0, r0; move r1, zero; move r2, zero }; \ + jrp lr; \ + STD_ENDPROC(__get_user_##bytes); \ + .pushsection __ex_table,"a"; \ + .word 1b, get_user_fault; \ + .popsection + +__get_user_N(1, lb_u) +__get_user_N(2, lh_u) +__get_user_N(4, lw) + +/* + * __get_user_8 takes a pointer in r0, and returns 0 in r2 + * on success, with the value in r0/r1; or else -EFAULT in r2. + */ + STD_ENTRY(__get_user_8); +1: { lw r0, r0; addi r1, r0, 4 }; +2: { lw r1, r1; move r2, zero }; + jrp lr; + STD_ENDPROC(__get_user_8); + .pushsection __ex_table,"a"; + .word 1b, get_user_fault; + .word 2b, get_user_fault; + .popsection + +/* + * __put_user_N functions take a value in r0 and a pointer in r1, + * and return 0 in r0 on success or -EFAULT on failure. + */ +#define __put_user_N(bytes, STORE) \ + STD_ENTRY(__put_user_##bytes); \ +1: { STORE r1, r0; move r0, zero }; \ + jrp lr; \ + STD_ENDPROC(__put_user_##bytes); \ + .pushsection __ex_table,"a"; \ + .word 1b, put_user_fault; \ + .popsection + +__put_user_N(1, sb) +__put_user_N(2, sh) +__put_user_N(4, sw) + +/* + * __put_user_8 takes a value in r0/r1 and a pointer in r2, + * and returns 0 in r0 on success or -EFAULT on failure. + */ +STD_ENTRY(__put_user_8) +1: { sw r2, r0; addi r2, r2, 4 } +2: { sw r2, r1; move r0, zero } + jrp lr + STD_ENDPROC(__put_user_8) + .pushsection __ex_table,"a" + .word 1b, put_user_fault + .word 2b, put_user_fault + .popsection + + +/* + * strnlen_user_asm takes the pointer in r0, and the length bound in r1. + * It returns the length, including the terminating NUL, or zero on exception. + * If length is greater than the bound, returns one plus the bound. + */ +STD_ENTRY(strnlen_user_asm) + { bz r1, 2f; addi r3, r0, -1 } /* bias down to include NUL */ +1: { lb_u r4, r0; addi r1, r1, -1 } + bz r4, 2f + { bnzt r1, 1b; addi r0, r0, 1 } +2: { sub r0, r0, r3; jrp lr } + STD_ENDPROC(strnlen_user_asm) + .pushsection .fixup,"ax" +strnlen_user_fault: + { move r0, zero; jrp lr } + ENDPROC(strnlen_user_fault) + .section __ex_table,"a" + .word 1b, strnlen_user_fault + .popsection + +/* + * strncpy_from_user_asm takes the kernel target pointer in r0, + * the userspace source pointer in r1, and the length bound (including + * the trailing NUL) in r2. On success, it returns the string length + * (not including the trailing NUL), or -EFAULT on failure. + */ +STD_ENTRY(strncpy_from_user_asm) + { bz r2, 2f; move r3, r0 } +1: { lb_u r4, r1; addi r1, r1, 1; addi r2, r2, -1 } + { sb r0, r4; addi r0, r0, 1 } + bz r2, 2f + bnzt r4, 1b + addi r0, r0, -1 /* don't count the trailing NUL */ +2: { sub r0, r0, r3; jrp lr } + STD_ENDPROC(strncpy_from_user_asm) + .pushsection .fixup,"ax" +strncpy_from_user_fault: + { movei r0, -EFAULT; jrp lr } + ENDPROC(strncpy_from_user_fault) + .section __ex_table,"a" + .word 1b, strncpy_from_user_fault + .popsection + +/* + * clear_user_asm takes the user target address in r0 and the + * number of bytes to zero in r1. + * It returns the number of uncopiable bytes (hopefully zero) in r0. + * Note that we don't use a separate .fixup section here since we fall + * through into the "fixup" code as the last straight-line bundle anyway. + */ +STD_ENTRY(clear_user_asm) + { bz r1, 2f; or r2, r0, r1 } + andi r2, r2, 3 + bzt r2, .Lclear_aligned_user_asm +1: { sb r0, zero; addi r0, r0, 1; addi r1, r1, -1 } + bnzt r1, 1b +2: { move r0, r1; jrp lr } + .pushsection __ex_table,"a" + .word 1b, 2b + .popsection + +.Lclear_aligned_user_asm: +1: { sw r0, zero; addi r0, r0, 4; addi r1, r1, -4 } + bnzt r1, 1b +2: { move r0, r1; jrp lr } + STD_ENDPROC(clear_user_asm) + .pushsection __ex_table,"a" + .word 1b, 2b + .popsection + +/* + * flush_user_asm takes the user target address in r0 and the + * number of bytes to flush in r1. + * It returns the number of unflushable bytes (hopefully zero) in r0. + */ +STD_ENTRY(flush_user_asm) + bz r1, 2f + { movei r2, L2_CACHE_BYTES; add r1, r0, r1 } + { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 } + { and r0, r0, r2; and r1, r1, r2 } + { sub r1, r1, r0 } +1: { flush r0; addi r1, r1, -CHIP_FLUSH_STRIDE() } + { addi r0, r0, CHIP_FLUSH_STRIDE(); bnzt r1, 1b } +2: { move r0, r1; jrp lr } + STD_ENDPROC(flush_user_asm) + .pushsection __ex_table,"a" + .word 1b, 2b + .popsection + +/* + * inv_user_asm takes the user target address in r0 and the + * number of bytes to invalidate in r1. + * It returns the number of not inv'able bytes (hopefully zero) in r0. + */ +STD_ENTRY(inv_user_asm) + bz r1, 2f + { movei r2, L2_CACHE_BYTES; add r1, r0, r1 } + { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 } + { and r0, r0, r2; and r1, r1, r2 } + { sub r1, r1, r0 } +1: { inv r0; addi r1, r1, -CHIP_INV_STRIDE() } + { addi r0, r0, CHIP_INV_STRIDE(); bnzt r1, 1b } +2: { move r0, r1; jrp lr } + STD_ENDPROC(inv_user_asm) + .pushsection __ex_table,"a" + .word 1b, 2b + .popsection + +/* + * finv_user_asm takes the user target address in r0 and the + * number of bytes to flush-invalidate in r1. + * It returns the number of not finv'able bytes (hopefully zero) in r0. + */ +STD_ENTRY(finv_user_asm) + bz r1, 2f + { movei r2, L2_CACHE_BYTES; add r1, r0, r1 } + { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 } + { and r0, r0, r2; and r1, r1, r2 } + { sub r1, r1, r0 } +1: { finv r0; addi r1, r1, -CHIP_FINV_STRIDE() } + { addi r0, r0, CHIP_FINV_STRIDE(); bnzt r1, 1b } +2: { move r0, r1; jrp lr } + STD_ENDPROC(finv_user_asm) + .pushsection __ex_table,"a" + .word 1b, 2b + .popsection |