diff options
Diffstat (limited to 'arch/microblaze')
| -rw-r--r-- | arch/microblaze/include/asm/pgtable.h | 536 | ||||
| -rw-r--r-- | arch/microblaze/include/asm/sections.h | 3 | ||||
| -rw-r--r-- | arch/microblaze/mm/pgtable.c | 286 |
3 files changed, 825 insertions, 0 deletions
diff --git a/arch/microblaze/include/asm/pgtable.h b/arch/microblaze/include/asm/pgtable.h index 254fd4b..4c57a58 100644 --- a/arch/microblaze/include/asm/pgtable.h +++ b/arch/microblaze/include/asm/pgtable.h @@ -1,4 +1,6 @@ /* + * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu> + * Copyright (C) 2008-2009 PetaLogix * Copyright (C) 2006 Atmark Techno, Inc. * * This file is subject to the terms and conditions of the GNU General Public @@ -14,6 +16,8 @@ #define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \ remap_pfn_range(vma, vaddr, pfn, size, prot) +#ifndef CONFIG_MMU + #define pgd_present(pgd) (1) /* pages are always present on non MMU */ #define pgd_none(pgd) (0) #define pgd_bad(pgd) (0) @@ -47,6 +51,538 @@ static inline int pte_file(pte_t pte) { return 0; } #define arch_enter_lazy_cpu_mode() do {} while (0) +#else /* CONFIG_MMU */ + +#include <asm-generic/4level-fixup.h> + +#ifdef __KERNEL__ +#ifndef __ASSEMBLY__ + +#include <linux/sched.h> +#include <linux/threads.h> +#include <asm/processor.h> /* For TASK_SIZE */ +#include <asm/mmu.h> +#include <asm/page.h> + +#define FIRST_USER_ADDRESS 0 + +extern unsigned long va_to_phys(unsigned long address); +extern pte_t *va_to_pte(unsigned long address); +extern unsigned long ioremap_bot, ioremap_base; + +/* + * The following only work if pte_present() is true. + * Undefined behaviour if not.. + */ + +static inline int pte_special(pte_t pte) { return 0; } + +static inline pte_t pte_mkspecial(pte_t pte) { return pte; } + +/* Start and end of the vmalloc area. */ +/* Make sure to map the vmalloc area above the pinned kernel memory area + of 32Mb. */ +#define VMALLOC_START (CONFIG_KERNEL_START + \ + max(32 * 1024 * 1024UL, memory_size)) +#define VMALLOC_END ioremap_bot +#define VMALLOC_VMADDR(x) ((unsigned long)(x)) + +#endif /* __ASSEMBLY__ */ + +/* + * The MicroBlaze MMU is identical to the PPC-40x MMU, and uses a hash + * table containing PTEs, together with a set of 16 segment registers, to + * define the virtual to physical address mapping. + * + * We use the hash table as an extended TLB, i.e. a cache of currently + * active mappings. We maintain a two-level page table tree, much + * like that used by the i386, for the sake of the Linux memory + * management code. Low-level assembler code in hashtable.S + * (procedure hash_page) is responsible for extracting ptes from the + * tree and putting them into the hash table when necessary, and + * updating the accessed and modified bits in the page table tree. + */ + +/* + * The MicroBlaze processor has a TLB architecture identical to PPC-40x. The + * instruction and data sides share a unified, 64-entry, semi-associative + * TLB which is maintained totally under software control. In addition, the + * instruction side has a hardware-managed, 2,4, or 8-entry, fully-associative + * TLB which serves as a first level to the shared TLB. These two TLBs are + * known as the UTLB and ITLB, respectively (see "mmu.h" for definitions). + */ + +/* + * The normal case is that PTEs are 32-bits and we have a 1-page + * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages. -- paulus + * + */ + +/* PMD_SHIFT determines the size of the area mapped by the PTE pages */ +#define PMD_SHIFT (PAGE_SHIFT + PTE_SHIFT) +#define PMD_SIZE (1UL << PMD_SHIFT) +#define PMD_MASK (~(PMD_SIZE-1)) + +/* PGDIR_SHIFT determines what a top-level page table entry can map */ +#define PGDIR_SHIFT PMD_SHIFT +#define PGDIR_SIZE (1UL << PGDIR_SHIFT) +#define PGDIR_MASK (~(PGDIR_SIZE-1)) + +/* + * entries per page directory level: our page-table tree is two-level, so + * we don't really have any PMD directory. + */ +#define PTRS_PER_PTE (1 << PTE_SHIFT) +#define PTRS_PER_PMD 1 +#define PTRS_PER_PGD (1 << (32 - PGDIR_SHIFT)) + +#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE) +#define FIRST_USER_PGD_NR 0 + +#define USER_PGD_PTRS (PAGE_OFFSET >> PGDIR_SHIFT) +#define KERNEL_PGD_PTRS (PTRS_PER_PGD-USER_PGD_PTRS) + +#define pte_ERROR(e) \ + printk(KERN_ERR "%s:%d: bad pte "PTE_FMT".\n", \ + __FILE__, __LINE__, pte_val(e)) +#define pmd_ERROR(e) \ + printk(KERN_ERR "%s:%d: bad pmd %08lx.\n", \ + __FILE__, __LINE__, pmd_val(e)) +#define pgd_ERROR(e) \ + printk(KERN_ERR "%s:%d: bad pgd %08lx.\n", \ + __FILE__, __LINE__, pgd_val(e)) + +/* + * Bits in a linux-style PTE. These match the bits in the + * (hardware-defined) PTE as closely as possible. + */ + +/* There are several potential gotchas here. The hardware TLBLO + * field looks like this: + * + * 0 1 2 3 4 ... 18 19 20 21 22 23 24 25 26 27 28 29 30 31 + * RPN..................... 0 0 EX WR ZSEL....... W I M G + * + * Where possible we make the Linux PTE bits match up with this + * + * - bits 20 and 21 must be cleared, because we use 4k pages (4xx can + * support down to 1k pages), this is done in the TLBMiss exception + * handler. + * - We use only zones 0 (for kernel pages) and 1 (for user pages) + * of the 16 available. Bit 24-26 of the TLB are cleared in the TLB + * miss handler. Bit 27 is PAGE_USER, thus selecting the correct + * zone. + * - PRESENT *must* be in the bottom two bits because swap cache + * entries use the top 30 bits. Because 4xx doesn't support SMP + * anyway, M is irrelevant so we borrow it for PAGE_PRESENT. Bit 30 + * is cleared in the TLB miss handler before the TLB entry is loaded. + * - All other bits of the PTE are loaded into TLBLO without + * * modification, leaving us only the bits 20, 21, 24, 25, 26, 30 for + * software PTE bits. We actually use use bits 21, 24, 25, and + * 30 respectively for the software bits: ACCESSED, DIRTY, RW, and + * PRESENT. + */ + +/* Definitions for MicroBlaze. */ +#define _PAGE_GUARDED 0x001 /* G: page is guarded from prefetch */ +#define _PAGE_PRESENT 0x002 /* software: PTE contains a translation */ +#define _PAGE_NO_CACHE 0x004 /* I: caching is inhibited */ +#define _PAGE_WRITETHRU 0x008 /* W: caching is write-through */ +#define _PAGE_USER 0x010 /* matches one of the zone permission bits */ +#define _PAGE_RW 0x040 /* software: Writes permitted */ +#define _PAGE_DIRTY 0x080 /* software: dirty page */ +#define _PAGE_HWWRITE 0x100 /* hardware: Dirty & RW, set in exception */ +#define _PAGE_HWEXEC 0x200 /* hardware: EX permission */ +#define _PAGE_ACCESSED 0x400 /* software: R: page referenced */ +#define _PMD_PRESENT PAGE_MASK + +/* + * Some bits are unused... + */ +#ifndef _PAGE_HASHPTE +#define _PAGE_HASHPTE 0 +#endif +#ifndef _PTE_NONE_MASK +#define _PTE_NONE_MASK 0 +#endif +#ifndef _PAGE_SHARED +#define _PAGE_SHARED 0 +#endif +#ifndef _PAGE_HWWRITE +#define _PAGE_HWWRITE 0 +#endif +#ifndef _PAGE_HWEXEC +#define _PAGE_HWEXEC 0 +#endif +#ifndef _PAGE_EXEC +#define _PAGE_EXEC 0 +#endif + +#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY) + +/* + * Note: the _PAGE_COHERENT bit automatically gets set in the hardware + * PTE if CONFIG_SMP is defined (hash_page does this); there is no need + * to have it in the Linux PTE, and in fact the bit could be reused for + * another purpose. -- paulus. + */ +#define _PAGE_BASE (_PAGE_PRESENT | _PAGE_ACCESSED) +#define _PAGE_WRENABLE (_PAGE_RW | _PAGE_DIRTY | _PAGE_HWWRITE) + +#define _PAGE_KERNEL \ + (_PAGE_BASE | _PAGE_WRENABLE | _PAGE_SHARED | _PAGE_HWEXEC) + +#define _PAGE_IO (_PAGE_KERNEL | _PAGE_NO_CACHE | _PAGE_GUARDED) + +#define PAGE_NONE __pgprot(_PAGE_BASE) +#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER) +#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC) +#define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW) +#define PAGE_SHARED_X \ + __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_EXEC) +#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER) +#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC) + +#define PAGE_KERNEL __pgprot(_PAGE_KERNEL) +#define PAGE_KERNEL_RO __pgprot(_PAGE_BASE | _PAGE_SHARED) +#define PAGE_KERNEL_CI __pgprot(_PAGE_IO) + +/* + * We consider execute permission the same as read. + * Also, write permissions imply read permissions. + */ +#define __P000 PAGE_NONE +#define __P001 PAGE_READONLY_X +#define __P010 PAGE_COPY +#define __P011 PAGE_COPY_X +#define __P100 PAGE_READONLY +#define __P101 PAGE_READONLY_X +#define __P110 PAGE_COPY +#define __P111 PAGE_COPY_X + +#define __S000 PAGE_NONE +#define __S001 PAGE_READONLY_X +#define __S010 PAGE_SHARED +#define __S011 PAGE_SHARED_X +#define __S100 PAGE_READONLY +#define __S101 PAGE_READONLY_X +#define __S110 PAGE_SHARED +#define __S111 PAGE_SHARED_X + +#ifndef __ASSEMBLY__ +/* + * ZERO_PAGE is a global shared page that is always zero: used + * for zero-mapped memory areas etc.. + */ +extern unsigned long empty_zero_page[1024]; +#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page)) + +#endif /* __ASSEMBLY__ */ + +#define pte_none(pte) ((pte_val(pte) & ~_PTE_NONE_MASK) == 0) +#define pte_present(pte) (pte_val(pte) & _PAGE_PRESENT) +#define pte_clear(mm, addr, ptep) \ + do { set_pte_at((mm), (addr), (ptep), __pte(0)); } while (0) + +#define pmd_none(pmd) (!pmd_val(pmd)) +#define pmd_bad(pmd) ((pmd_val(pmd) & _PMD_PRESENT) == 0) +#define pmd_present(pmd) ((pmd_val(pmd) & _PMD_PRESENT) != 0) +#define pmd_clear(pmdp) do { pmd_val(*(pmdp)) = 0; } while (0) + +#define pte_page(x) (mem_map + (unsigned long) \ + ((pte_val(x) - memory_start) >> PAGE_SHIFT)) +#define PFN_SHIFT_OFFSET (PAGE_SHIFT) + +#define pte_pfn(x) (pte_val(x) >> PFN_SHIFT_OFFSET) + +#define pfn_pte(pfn, prot) \ + __pte(((pte_basic_t)(pfn) << PFN_SHIFT_OFFSET) | pgprot_val(prot)) + +#ifndef __ASSEMBLY__ +/* + * The "pgd_xxx()" functions here are trivial for a folded two-level + * setup: the pgd is never bad, and a pmd always exists (as it's folded + * into the pgd entry) + */ +static inline int pgd_none(pgd_t pgd) { return 0; } +static inline int pgd_bad(pgd_t pgd) { return 0; } +static inline int pgd_present(pgd_t pgd) { return 1; } +#define pgd_clear(xp) do { } while (0) +#define pgd_page(pgd) \ + ((unsigned long) __va(pgd_val(pgd) & PAGE_MASK)) + +/* + * The following only work if pte_present() is true. + * Undefined behaviour if not.. + */ +static inline int pte_read(pte_t pte) { return pte_val(pte) & _PAGE_USER; } +static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW; } +static inline int pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_EXEC; } +static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; } +static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; } +/* FIXME */ +static inline int pte_file(pte_t pte) { return 0; } + +static inline void pte_uncache(pte_t pte) { pte_val(pte) |= _PAGE_NO_CACHE; } +static inline void pte_cache(pte_t pte) { pte_val(pte) &= ~_PAGE_NO_CACHE; } + +static inline pte_t pte_rdprotect(pte_t pte) \ + { pte_val(pte) &= ~_PAGE_USER; return pte; } +static inline pte_t pte_wrprotect(pte_t pte) \ + { pte_val(pte) &= ~(_PAGE_RW | _PAGE_HWWRITE); return pte; } +static inline pte_t pte_exprotect(pte_t pte) \ + { pte_val(pte) &= ~_PAGE_EXEC; return pte; } +static inline pte_t pte_mkclean(pte_t pte) \ + { pte_val(pte) &= ~(_PAGE_DIRTY | _PAGE_HWWRITE); return pte; } +static inline pte_t pte_mkold(pte_t pte) \ + { pte_val(pte) &= ~_PAGE_ACCESSED; return pte; } + +static inline pte_t pte_mkread(pte_t pte) \ + { pte_val(pte) |= _PAGE_USER; return pte; } +static inline pte_t pte_mkexec(pte_t pte) \ + { pte_val(pte) |= _PAGE_USER | _PAGE_EXEC; return pte; } +static inline pte_t pte_mkwrite(pte_t pte) \ + { pte_val(pte) |= _PAGE_RW; return pte; } +static inline pte_t pte_mkdirty(pte_t pte) \ + { pte_val(pte) |= _PAGE_DIRTY; return pte; } +static inline pte_t pte_mkyoung(pte_t pte) \ + { pte_val(pte) |= _PAGE_ACCESSED; return pte; } + +/* + * Conversion functions: convert a page and protection to a page entry, + * and a page entry and page directory to the page they refer to. + */ + +static inline pte_t mk_pte_phys(phys_addr_t physpage, pgprot_t pgprot) +{ + pte_t pte; + pte_val(pte) = physpage | pgprot_val(pgprot); + return pte; +} + +#define mk_pte(page, pgprot) \ +({ \ + pte_t pte; \ + pte_val(pte) = (((page - mem_map) << PAGE_SHIFT) + memory_start) | \ + pgprot_val(pgprot); \ + pte; \ +}) + +static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) +{ + pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); + return pte; +} + +/* + * Atomic PTE updates. + * + * pte_update clears and sets bit atomically, and returns + * the old pte value. + * The ((unsigned long)(p+1) - 4) hack is to get to the least-significant + * 32 bits of the PTE regardless of whether PTEs are 32 or 64 bits. + */ +static inline unsigned long pte_update(pte_t *p, unsigned long clr, + unsigned long set) +{ + unsigned long old, tmp, msr; + + __asm__ __volatile__("\ + msrclr %2, 0x2\n\ + nop\n\ + lw %0, %4, r0\n\ + andn %1, %0, %5\n\ + or %1, %1, %6\n\ + sw %1, %4, r0\n\ + mts rmsr, %2\n\ + nop" + : "=&r" (old), "=&r" (tmp), "=&r" (msr), "=m" (*p) + : "r" ((unsigned long)(p+1) - 4), "r" (clr), "r" (set), "m" (*p) + : "cc"); + + return old; +} + +/* + * set_pte stores a linux PTE into the linux page table. + */ +static inline void set_pte(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte) +{ + *ptep = pte; +} + +static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte) +{ + *ptep = pte; +} + +static inline int ptep_test_and_clear_young(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + return (pte_update(ptep, _PAGE_ACCESSED, 0) & _PAGE_ACCESSED) != 0; +} + +static inline int ptep_test_and_clear_dirty(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + return (pte_update(ptep, \ + (_PAGE_DIRTY | _PAGE_HWWRITE), 0) & _PAGE_DIRTY) != 0; +} + +static inline pte_t ptep_get_and_clear(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + return __pte(pte_update(ptep, ~_PAGE_HASHPTE, 0)); +} + +/*static inline void ptep_set_wrprotect(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + pte_update(ptep, (_PAGE_RW | _PAGE_HWWRITE), 0); +}*/ + +static inline void ptep_mkdirty(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + pte_update(ptep, 0, _PAGE_DIRTY); +} + +/*#define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)*/ + +/* Convert pmd entry to page */ +/* our pmd entry is an effective address of pte table*/ +/* returns effective address of the pmd entry*/ +#define pmd_page_kernel(pmd) ((unsigned long) (pmd_val(pmd) & PAGE_MASK)) + +/* returns struct *page of the pmd entry*/ +#define pmd_page(pmd) (pfn_to_page(__pa(pmd_val(pmd)) >> PAGE_SHIFT)) + +/* to find an entry in a kernel page-table-directory */ +#define pgd_offset_k(address) pgd_offset(&init_mm, address) + +/* to find an entry in a page-table-directory */ +#define pgd_index(address) ((address) >> PGDIR_SHIFT) +#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address)) + +/* Find an entry in the second-level page table.. */ +static inline pmd_t *pmd_offset(pgd_t *dir, unsigned long address) +{ + return (pmd_t *) dir; +} + +/* Find an entry in the third-level page table.. */ +#define pte_index(address) \ + (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) +#define pte_offset_kernel(dir, addr) \ + ((pte_t *) pmd_page_kernel(*(dir)) + pte_index(addr)) +#define pte_offset_map(dir, addr) \ + ((pte_t *) kmap_atomic(pmd_page(*(dir)), KM_PTE0) + pte_index(addr)) +#define pte_offset_map_nested(dir, addr) \ + ((pte_t *) kmap_atomic(pmd_page(*(dir)), KM_PTE1) + pte_index(addr)) + +#define pte_unmap(pte) kunmap_atomic(pte, KM_PTE0) +#define pte_unmap_nested(pte) kunmap_atomic(pte, KM_PTE1) + +/* Encode and decode a nonlinear file mapping entry */ +#define PTE_FILE_MAX_BITS 29 +#define pte_to_pgoff(pte) (pte_val(pte) >> 3) +#define pgoff_to_pte(off) ((pte_t) { ((off) << 3) }) + +extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; + +/* + * When flushing the tlb entry for a page, we also need to flush the hash + * table entry. flush_hash_page is assembler (for speed) in hashtable.S. + */ +extern int flush_hash_page(unsigned context, unsigned long va, pte_t *ptep); + +/* Add an HPTE to the hash table */ +extern void add_hash_page(unsigned context, unsigned long va, pte_t *ptep); + +/* + * Encode and decode a swap entry. + * Note that the bits we use in a PTE for representing a swap entry + * must not include the _PAGE_PRESENT bit, or the _PAGE_HASHPTE bit + * (if used). -- paulus + */ +#define __swp_type(entry) ((entry).val & 0x3f) +#define __swp_offset(entry) ((entry).val >> 6) +#define __swp_entry(type, offset) \ + ((swp_entry_t) { (type) | ((offset) << 6) }) +#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 2 }) +#define __swp_entry_to_pte(x) ((pte_t) { (x).val << 2 }) + + +/* CONFIG_APUS */ +/* For virtual address to physical address conversion */ +extern void cache_clear(__u32 addr, int length); +extern void cache_push(__u32 addr, int length); +extern int mm_end_of_chunk(unsigned long addr, int len); +extern unsigned long iopa(unsigned long addr); +/* extern unsigned long mm_ptov(unsigned long addr) \ + __attribute__ ((const)); TBD */ + +/* Values for nocacheflag and cmode */ +/* These are not used by the APUS kernel_map, but prevents + * compilation errors. + */ +#define IOMAP_FULL_CACHING 0 +#define IOMAP_NOCACHE_SER 1 +#define IOMAP_NOCACHE_NONSER 2 +#define IOMAP_NO_COPYBACK 3 + +/* + * Map some physical address range into the kernel address space. + */ +extern unsigned long kernel_map(unsigned long paddr, unsigned long size, + int nocacheflag, unsigned long *memavailp); + +/* + * Set cache mode of (kernel space) address range. + */ +extern void kernel_set_cachemode(unsigned long address, unsigned long size, + unsigned int cmode); + +/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */ +#define kern_addr_valid(addr) (1) + +#define io_remap_page_range remap_page_range + +/* + * No page table caches to initialise + */ +#define pgtable_cache_init() do { } while (0) + +void do_page_fault(struct pt_regs *regs, unsigned long address, + unsigned long error_code); + +void __init io_block_mapping(unsigned long virt, phys_addr_t phys, + unsigned int size, int flags); + +void __init adjust_total_lowmem(void); +void mapin_ram(void); +int map_page(unsigned long va, phys_addr_t pa, int flags); + +extern int mem_init_done; +extern unsigned long ioremap_base; +extern unsigned long ioremap_bot; + +asmlinkage void __init mmu_init(void); + +void __init *early_get_page(void); + +void *consistent_alloc(int gfp, size_t size, dma_addr_t *dma_handle); +void consistent_free(void *vaddr); +void consistent_sync(void *vaddr, size_t size, int direction); +void consistent_sync_page(struct page *page, unsigned long offset, + size_t size, int direction); +#endif /* __ASSEMBLY__ */ +#endif /* __KERNEL__ */ + +#endif /* CONFIG_MMU */ + #ifndef __ASSEMBLY__ #include <asm-generic/pgtable.h> diff --git a/arch/microblaze/include/asm/sections.h b/arch/microblaze/include/asm/sections.h index 8434a43..4487e15 100644 --- a/arch/microblaze/include/asm/sections.h +++ b/arch/microblaze/include/asm/sections.h @@ -1,4 +1,6 @@ /* + * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu> + * Copyright (C) 2008-2009 PetaLogix * Copyright (C) 2006 Atmark Techno, Inc. * * This file is subject to the terms and conditions of the GNU General Public @@ -14,6 +16,7 @@ # ifndef __ASSEMBLY__ extern char _ssbss[], _esbss[]; extern unsigned long __ivt_start[], __ivt_end[]; +extern char _etext[], _stext[]; # ifdef CONFIG_MTD_UCLINUX extern char *_ebss; diff --git a/arch/microblaze/mm/pgtable.c b/arch/microblaze/mm/pgtable.c new file mode 100644 index 0000000..46c4ca5 --- /dev/null +++ b/arch/microblaze/mm/pgtable.c @@ -0,0 +1,286 @@ +/* + * This file contains the routines setting up the linux page tables. + * + * Copyright (C) 2008 Michal Simek + * Copyright (C) 2008 PetaLogix + * + * Copyright (C) 2007 Xilinx, Inc. All rights reserved. + * + * Derived from arch/ppc/mm/pgtable.c: + * -- paulus + * + * Derived from arch/ppc/mm/init.c: + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) + * and Cort Dougan (PReP) (cort@cs.nmt.edu) + * Copyright (C) 1996 Paul Mackerras + * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). + * + * Derived from "arch/i386/mm/init.c" + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file COPYING in the main directory of this + * archive for more details. + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/vmalloc.h> +#include <linux/init.h> + +#include <asm/pgtable.h> +#include <asm/pgalloc.h> +#include <linux/io.h> +#include <asm/mmu.h> +#include <asm/sections.h> + +#define flush_HPTE(X, va, pg) _tlbie(va) + +unsigned long ioremap_base; +unsigned long ioremap_bot; + +/* The maximum lowmem defaults to 768Mb, but this can be configured to + * another value. + */ +#define MAX_LOW_MEM CONFIG_LOWMEM_SIZE + +#ifndef CONFIG_SMP +struct pgtable_cache_struct quicklists; +#endif + +static void __iomem *__ioremap(phys_addr_t addr, unsigned long size, + unsigned long flags) +{ + unsigned long v, i; + phys_addr_t p; + int err; + + /* + * Choose an address to map it to. + * Once the vmalloc system is running, we use it. + * Before then, we use space going down from ioremap_base + * (ioremap_bot records where we're up to). + */ + p = addr & PAGE_MASK; + size = PAGE_ALIGN(addr + size) - p; + + /* + * Don't allow anybody to remap normal RAM that we're using. + * mem_init() sets high_memory so only do the check after that. + * + * However, allow remap of rootfs: TBD + */ + if (mem_init_done && + p >= memory_start && p < virt_to_phys(high_memory) && + !(p >= virt_to_phys((unsigned long)&__bss_stop) && + p < virt_to_phys((unsigned long)__bss_stop))) { + printk(KERN_WARNING "__ioremap(): phys addr "PTE_FMT + " is RAM lr %p\n", (unsigned long)p, + __builtin_return_address(0)); + return NULL; + } + + if (size == 0) + return NULL; + + /* + * Is it already mapped? If the whole area is mapped then we're + * done, otherwise remap it since we want to keep the virt addrs for + * each request contiguous. + * + * We make the assumption here that if the bottom and top + * of the range we want are mapped then it's mapped to the + * same virt address (and this is contiguous). + * -- Cort + */ + + if (mem_init_done) { + struct vm_struct *area; + area = get_vm_area(size, VM_IOREMAP); + if (area == NULL) + return NULL; + v = VMALLOC_VMADDR(area->addr); + } else { + v = (ioremap_bot -= size); + } + + if ((flags & _PAGE_PRESENT) == 0) + flags |= _PAGE_KERNEL; + if (flags & _PAGE_NO_CACHE) + flags |= _PAGE_GUARDED; + + err = 0; + for (i = 0; i < size && err == 0; i += PAGE_SIZE) + err = map_page(v + i, p + i, flags); + if (err) { + if (mem_init_done) + vfree((void *)v); + return NULL; + } + + return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK)); +} + +void __iomem *ioremap(phys_addr_t addr, unsigned long size) +{ + return __ioremap(addr, size, _PAGE_NO_CACHE); +} +EXPORT_SYMBOL(ioremap); + +void iounmap(void *addr) +{ + if (addr > high_memory && (unsigned long) addr < ioremap_bot) + vfree((void *) (PAGE_MASK & (unsigned long) addr)); +} +EXPORT_SYMBOL(iounmap); + + +int map_page(unsigned long va, phys_addr_t pa, int flags) +{ + pmd_t *pd; + pte_t *pg; + int err = -ENOMEM; + /* spin_lock(&init_mm.page_table_lock); */ + /* Use upper 10 bits of VA to index the first level map */ + pd = pmd_offset(pgd_offset_k(va), va); + /* Use middle 10 bits of VA to index the second-level map */ + pg = pte_alloc_kernel(pd, va); /* from powerpc - pgtable.c */ + /* pg = pte_alloc_kernel(&init_mm, pd, va); */ + + if (pg != NULL) { + err = 0; + set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, + __pgprot(flags))); + if (mem_init_done) + flush_HPTE(0, va, pmd_val(*pd)); + /* flush_HPTE(0, va, pg); */ + + } + /* spin_unlock(&init_mm.page_table_lock); */ + return err; +} + +void __init adjust_total_lowmem(void) +{ +/* TBD */ +#if 0 + unsigned long max_low_mem = MAX_LOW_MEM; + + if (total_lowmem > max_low_mem) { + total_lowmem = max_low_mem; +#ifndef CONFIG_HIGHMEM + printk(KERN_INFO "Warning, memory limited to %ld Mb, use " + "CONFIG_HIGHMEM to reach %ld Mb\n", + max_low_mem >> 20, total_memory >> 20); + total_memory = total_lowmem; +#endif /* CONFIG_HIGHMEM */ + } +#endif +} + +static void show_tmem(unsigned long tmem) +{ + volatile unsigned long a; + a = a + tmem; +} + +/* + * Map in all of physical memory starting at CONFIG_KERNEL_START. + */ +void __init mapin_ram(void) +{ + unsigned long v, p, s, f; + + v = CONFIG_KERNEL_START; + p = memory_start; + show_tmem(memory_size); + for (s = 0; s < memory_size; s += PAGE_SIZE) { + f = _PAGE_PRESENT | _PAGE_ACCESSED | + _PAGE_SHARED | _PAGE_HWEXEC; + if ((char *) v < _stext || (char *) v >= _etext) + f |= _PAGE_WRENABLE; + else + /* On the MicroBlaze, no user access + forces R/W kernel access */ + f |= _PAGE_USER; + map_page(v, p, f); + v += PAGE_SIZE; + p += PAGE_SIZE; + } +} + +/* is x a power of 2? */ +#define is_power_of_2(x) ((x) != 0 && (((x) & ((x) - 1)) == 0)) + +/* + * Set up a mapping for a block of I/O. + * virt, phys, size must all be page-aligned. + * This should only be called before ioremap is called. + */ +void __init io_block_mapping(unsigned long virt, phys_addr_t phys, + unsigned int size, int flags) +{ + int i; + + if (virt > CONFIG_KERNEL_START && virt < ioremap_bot) + ioremap_bot = ioremap_base = virt; + + /* Put it in the page tables. */ + for (i = 0; i < size; i += PAGE_SIZE) + map_page(virt + i, phys + i, flags); +} + +/* Scan the real Linux page tables and return a PTE pointer for + * a virtual address in a context. + * Returns true (1) if PTE was found, zero otherwise. The pointer to + * the PTE pointer is unmodified if PTE is not found. + */ +static int get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep) +{ + pgd_t *pgd; + pmd_t *pmd; + pte_t *pte; + int retval = 0; + + pgd = pgd_offset(mm, addr & PAGE_MASK); + if (pgd) { + pmd = pmd_offset(pgd, addr & PAGE_MASK); + if (pmd_present(*pmd)) { + pte = pte_offset_kernel(pmd, addr & PAGE_MASK); + if (pte) { + retval = 1; + *ptep = pte; + } + } + } + return retval; +} + +/* Find physical address for this virtual address. Normally used by + * I/O functions, but anyone can call it. + */ +unsigned long iopa(unsigned long addr) +{ + unsigned long pa; + + pte_t *pte; + struct mm_struct *mm; + + /* Allow mapping of user addresses (within the thread) + * for DMA if necessary. + */ + if (addr < TASK_SIZE) + mm = current->mm; + else + mm = &init_mm; + + pa = 0; + if (get_pteptr(mm, addr, &pte)) + pa = (pte_val(*pte) & PAGE_MASK) | (addr & ~PAGE_MASK); + + return pa; +} |