sparc,leon: Sparc-Leon SMP support

Support SMP for a Sparc-Leon multiprocessor system.
Add Leon specific SMP code to arch/sparc/kernel/leon_smp.c.

Signed-off-by: Konrad Eisele <konrad@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 468 insertions, 0 deletions

diff --git a/arch/sparc/kernel/leon_smp.c b/arch/sparc/kernel/leon_smp.c
new file mode 100644
index 0000000..05c0dad
--- /dev/null
+++ b/arch/sparc/kernel/leon_smp.c
@@ -0,0 +1,468 @@
+/* leon_smp.c: Sparc-Leon SMP support.
+ *
+ * based on sun4m_smp.c
+ * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB
+ * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB
+ */
+
+#include <asm/head.h>
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/threads.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/profile.h>
+#include <linux/pm.h>
+#include <linux/delay.h>
+
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+
+#include <asm/ptrace.h>
+#include <asm/atomic.h>
+#include <asm/irq_regs.h>
+
+#include <asm/delay.h>
+#include <asm/irq.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/oplib.h>
+#include <asm/cpudata.h>
+#include <asm/asi.h>
+#include <asm/leon.h>
+#include <asm/leon_amba.h>
+
+#ifdef CONFIG_SPARC_LEON
+
+#include "irq.h"
+
+extern ctxd_t *srmmu_ctx_table_phys;
+static int smp_processors_ready;
+extern volatile unsigned long cpu_callin_map[NR_CPUS];
+extern unsigned char boot_cpu_id;
+extern cpumask_t smp_commenced_mask;
+void __init leon_configure_cache_smp(void);
+
+static inline unsigned long do_swap(volatile unsigned long *ptr,
+				    unsigned long val)
+{
+	__asm__ __volatile__("swapa [%1] %2, %0\n\t" : "=&r"(val)
+			     : "r"(ptr), "i"(ASI_LEON_DCACHE_MISS)
+			     : "memory");
+	return val;
+}
+
+static void smp_setup_percpu_timer(void);
+
+void __cpuinit leon_callin(void)
+{
+	int cpuid = hard_smpleon_processor_id();
+
+	local_flush_cache_all();
+	local_flush_tlb_all();
+	leon_configure_cache_smp();
+
+	/* Get our local ticker going. */
+	smp_setup_percpu_timer();
+
+	calibrate_delay();
+	smp_store_cpu_info(cpuid);
+
+	local_flush_cache_all();
+	local_flush_tlb_all();
+
+	/*
+	 * Unblock the master CPU _only_ when the scheduler state
+	 * of all secondary CPUs will be up-to-date, so after
+	 * the SMP initialization the master will be just allowed
+	 * to call the scheduler code.
+	 * Allow master to continue.
+	 */
+	do_swap(&cpu_callin_map[cpuid], 1);
+
+	local_flush_cache_all();
+	local_flush_tlb_all();
+
+	cpu_probe();
+
+	/* Fix idle thread fields. */
+	__asm__ __volatile__("ld [%0], %%g6\n\t" : : "r"(&current_set[cpuid])
+			     : "memory" /* paranoid */);
+
+	/* Attach to the address space of init_task. */
+	atomic_inc(&init_mm.mm_count);
+	current->active_mm = &init_mm;
+
+	while (!cpu_isset(cpuid, smp_commenced_mask))
+		mb();
+
+	local_irq_enable();
+	cpu_set(cpuid, cpu_online_map);
+}
+
+/*
+ *	Cycle through the processors asking the PROM to start each one.
+ */
+
+extern struct linux_prom_registers smp_penguin_ctable;
+
+void __init leon_configure_cache_smp(void)
+{
+	unsigned long cfg = sparc_leon3_get_dcachecfg();
+	int me = smp_processor_id();
+
+	if (ASI_LEON3_SYSCTRL_CFG_SSIZE(cfg) > 4) {
+		printk(KERN_INFO "Note: SMP with snooping only works on 4k cache, found %dk(0x%x) on cpu %d, disabling caches\n",
+		     (unsigned int)ASI_LEON3_SYSCTRL_CFG_SSIZE(cfg),
+		     (unsigned int)cfg, (unsigned int)me);
+		sparc_leon3_disable_cache();
+	} else {
+		if (cfg & ASI_LEON3_SYSCTRL_CFG_SNOOPING) {
+			sparc_leon3_enable_snooping();
+		} else {
+			printk(KERN_INFO "Note: You have to enable snooping in the vhdl model cpu %d, disabling caches\n",
+			     me);
+			sparc_leon3_disable_cache();
+		}
+	}
+
+	local_flush_cache_all();
+	local_flush_tlb_all();
+}
+
+void leon_smp_setbroadcast(unsigned int mask)
+{
+	int broadcast =
+	    ((LEON3_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpstatus)) >>
+	      LEON3_IRQMPSTATUS_BROADCAST) & 1);
+	if (!broadcast) {
+		prom_printf("######## !!!! The irqmp-ctrl must have broadcast enabled, smp wont work !!!!! ####### nr cpus: %d\n",
+		     leon_smp_nrcpus());
+		if (leon_smp_nrcpus() > 1) {
+			BUG();
+		} else {
+			prom_printf("continue anyway\n");
+			return;
+		}
+	}
+	LEON_BYPASS_STORE_PA(&(leon3_irqctrl_regs->mpbroadcast), mask);
+}
+
+unsigned int leon_smp_getbroadcast(void)
+{
+	unsigned int mask;
+	mask = LEON_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpbroadcast));
+	return mask;
+}
+
+int leon_smp_nrcpus(void)
+{
+	int nrcpu =
+	    ((LEON3_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpstatus)) >>
+	      LEON3_IRQMPSTATUS_CPUNR) & 0xf) + 1;
+	return nrcpu;
+}
+
+void __init leon_boot_cpus(void)
+{
+	int nrcpu = leon_smp_nrcpus();
+	int me = smp_processor_id();
+
+	printk(KERN_INFO "%d:(%d:%d) cpus mpirq at 0x%x \n", (unsigned int)me,
+	       (unsigned int)nrcpu, (unsigned int)NR_CPUS,
+	       (unsigned int)&(leon3_irqctrl_regs->mpstatus));
+
+	leon_enable_irq_cpu(LEON3_IRQ_CROSS_CALL, me);
+	leon_enable_irq_cpu(LEON3_IRQ_TICKER, me);
+	leon_enable_irq_cpu(LEON3_IRQ_RESCHEDULE, me);
+
+	leon_smp_setbroadcast(1 << LEON3_IRQ_TICKER);
+
+	leon_configure_cache_smp();
+	smp_setup_percpu_timer();
+	local_flush_cache_all();
+
+}
+
+int __cpuinit leon_boot_one_cpu(int i)
+{
+
+	struct task_struct *p;
+	int timeout;
+
+	/* Cook up an idler for this guy. */
+	p = fork_idle(i);
+
+	current_set[i] = task_thread_info(p);
+
+	/* See trampoline.S:leon_smp_cpu_startup for details...
+	 * Initialize the contexts table
+	 * Since the call to prom_startcpu() trashes the structure,
+	 * we need to re-initialize it for each cpu
+	 */
+	smp_penguin_ctable.which_io = 0;
+	smp_penguin_ctable.phys_addr = (unsigned int)srmmu_ctx_table_phys;
+	smp_penguin_ctable.reg_size = 0;
+
+	/* whirrr, whirrr, whirrrrrrrrr... */
+	printk(KERN_INFO "Starting CPU %d : (irqmp: 0x%x)\n", (unsigned int)i,
+	       (unsigned int)&leon3_irqctrl_regs->mpstatus);
+	local_flush_cache_all();
+
+	LEON_BYPASS_STORE_PA(&(leon3_irqctrl_regs->mpstatus), 1 << i);
+
+	/* wheee... it's going... */
+	for (timeout = 0; timeout < 10000; timeout++) {
+		if (cpu_callin_map[i])
+			break;
+		udelay(200);
+	}
+	printk(KERN_INFO "Started CPU %d \n", (unsigned int)i);
+
+	if (!(cpu_callin_map[i])) {
+		printk(KERN_ERR "Processor %d is stuck.\n", i);
+		return -ENODEV;
+	} else {
+		leon_enable_irq_cpu(LEON3_IRQ_CROSS_CALL, i);
+		leon_enable_irq_cpu(LEON3_IRQ_TICKER, i);
+		leon_enable_irq_cpu(LEON3_IRQ_RESCHEDULE, i);
+	}
+
+	local_flush_cache_all();
+	return 0;
+}
+
+void __init leon_smp_done(void)
+{
+
+	int i, first;
+	int *prev;
+
+	/* setup cpu list for irq rotation */
+	first = 0;
+	prev = &first;
+	for (i = 0; i < NR_CPUS; i++) {
+		if (cpu_online(i)) {
+			*prev = i;
+			prev = &cpu_data(i).next;
+		}
+	}
+	*prev = first;
+	local_flush_cache_all();
+
+	/* Free unneeded trap tables */
+	if (!cpu_isset(1, cpu_present_map)) {
+		ClearPageReserved(virt_to_page(trapbase_cpu1));
+		init_page_count(virt_to_page(trapbase_cpu1));
+		free_page((unsigned long)trapbase_cpu1);
+		totalram_pages++;
+		num_physpages++;
+	}
+	if (!cpu_isset(2, cpu_present_map)) {
+		ClearPageReserved(virt_to_page(trapbase_cpu2));
+		init_page_count(virt_to_page(trapbase_cpu2));
+		free_page((unsigned long)trapbase_cpu2);
+		totalram_pages++;
+		num_physpages++;
+	}
+	if (!cpu_isset(3, cpu_present_map)) {
+		ClearPageReserved(virt_to_page(trapbase_cpu3));
+		init_page_count(virt_to_page(trapbase_cpu3));
+		free_page((unsigned long)trapbase_cpu3);
+		totalram_pages++;
+		num_physpages++;
+	}
+	/* Ok, they are spinning and ready to go. */
+	smp_processors_ready = 1;
+
+}
+
+void leon_irq_rotate(int cpu)
+{
+}
+
+static struct smp_funcall {
+	smpfunc_t func;
+	unsigned long arg1;
+	unsigned long arg2;
+	unsigned long arg3;
+	unsigned long arg4;
+	unsigned long arg5;
+	unsigned long processors_in[NR_CPUS];	/* Set when ipi entered. */
+	unsigned long processors_out[NR_CPUS];	/* Set when ipi exited. */
+} ccall_info;
+
+static DEFINE_SPINLOCK(cross_call_lock);
+
+/* Cross calls must be serialized, at least currently. */
+static void leon_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
+			    unsigned long arg2, unsigned long arg3,
+			    unsigned long arg4)
+{
+	if (smp_processors_ready) {
+		register int high = NR_CPUS - 1;
+		unsigned long flags;
+
+		spin_lock_irqsave(&cross_call_lock, flags);
+
+		{
+			/* If you make changes here, make sure gcc generates proper code... */
+			register smpfunc_t f asm("i0") = func;
+			register unsigned long a1 asm("i1") = arg1;
+			register unsigned long a2 asm("i2") = arg2;
+			register unsigned long a3 asm("i3") = arg3;
+			register unsigned long a4 asm("i4") = arg4;
+			register unsigned long a5 asm("i5") = 0;
+
+			__asm__ __volatile__("std %0, [%6]\n\t"
+					     "std %2, [%6 + 8]\n\t"
+					     "std %4, [%6 + 16]\n\t" : :
+					     "r"(f), "r"(a1), "r"(a2), "r"(a3),
+					     "r"(a4), "r"(a5),
+					     "r"(&ccall_info.func));
+		}
+
+		/* Init receive/complete mapping, plus fire the IPI's off. */
+		{
+			register int i;
+
+			cpu_clear(smp_processor_id(), mask);
+			cpus_and(mask, cpu_online_map, mask);
+			for (i = 0; i <= high; i++) {
+				if (cpu_isset(i, mask)) {
+					ccall_info.processors_in[i] = 0;
+					ccall_info.processors_out[i] = 0;
+					set_cpu_int(i, LEON3_IRQ_CROSS_CALL);
+
+				}
+			}
+		}
+
+		{
+			register int i;
+
+			i = 0;
+			do {
+				if (!cpu_isset(i, mask))
+					continue;
+
+				while (!ccall_info.processors_in[i])
+					barrier();
+			} while (++i <= high);
+
+			i = 0;
+			do {
+				if (!cpu_isset(i, mask))
+					continue;
+
+				while (!ccall_info.processors_out[i])
+					barrier();
+			} while (++i <= high);
+		}
+
+		spin_unlock_irqrestore(&cross_call_lock, flags);
+	}
+}
+
+/* Running cross calls. */
+void leon_cross_call_irq(void)
+{
+	int i = smp_processor_id();
+
+	ccall_info.processors_in[i] = 1;
+	ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
+			ccall_info.arg4, ccall_info.arg5);
+	ccall_info.processors_out[i] = 1;
+}
+
+void leon_percpu_timer_interrupt(struct pt_regs *regs)
+{
+	struct pt_regs *old_regs;
+	int cpu = smp_processor_id();
+
+	old_regs = set_irq_regs(regs);
+
+	leon_clear_profile_irq(cpu);
+
+	profile_tick(CPU_PROFILING);
+
+	if (!--prof_counter(cpu)) {
+		int user = user_mode(regs);
+
+		irq_enter();
+		update_process_times(user);
+		irq_exit();
+
+		prof_counter(cpu) = prof_multiplier(cpu);
+	}
+	set_irq_regs(old_regs);
+}
+
+static void __init smp_setup_percpu_timer(void)
+{
+	int cpu = smp_processor_id();
+
+	prof_counter(cpu) = prof_multiplier(cpu) = 1;
+}
+
+void __init leon_blackbox_id(unsigned *addr)
+{
+	int rd = *addr & 0x3e000000;
+	int rs1 = rd >> 11;
+
+	/* patch places where ___b_hard_smp_processor_id appears */
+	addr[0] = 0x81444000 | rd;	/* rd %asr17, reg */
+	addr[1] = 0x8130201c | rd | rs1;	/* srl reg, 0x1c, reg */
+	addr[2] = 0x01000000;	/* nop */
+}
+
+void __init leon_blackbox_current(unsigned *addr)
+{
+	int rd = *addr & 0x3e000000;
+	int rs1 = rd >> 11;
+
+	/* patch LOAD_CURRENT macro where ___b_load_current appears */
+	addr[0] = 0x81444000 | rd;	/* rd %asr17, reg */
+	addr[2] = 0x8130201c | rd | rs1;	/* srl reg, 0x1c, reg */
+	addr[4] = 0x81282002 | rd | rs1;	/* sll reg, 0x2, reg */
+
+}
+
+/*
+ * CPU idle callback function
+ * See .../arch/sparc/kernel/process.c
+ */
+void pmc_leon_idle(void)
+{
+	__asm__ volatile ("mov %g0, %asr19");
+}
+
+void __init leon_init_smp(void)
+{
+	/* Patch ipi15 trap table */
+	t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_leon - linux_trap_ipi15_sun4m);
+
+	BTFIXUPSET_BLACKBOX(hard_smp_processor_id, leon_blackbox_id);
+	BTFIXUPSET_BLACKBOX(load_current, leon_blackbox_current);
+	BTFIXUPSET_CALL(smp_cross_call, leon_cross_call, BTFIXUPCALL_NORM);
+	BTFIXUPSET_CALL(__hard_smp_processor_id, __leon_processor_id,
+			BTFIXUPCALL_NORM);
+
+#ifndef PMC_NO_IDLE
+	/* Assign power management IDLE handler */
+	pm_idle = pmc_leon_idle;
+	printk(KERN_INFO "leon: power management initialized\n");
+#endif
+
+}
+
+#endif /* CONFIG_SPARC_LEON */