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Diffstat (limited to 'arch/powerpc/platforms/85xx/smp.c')
-rw-r--r--arch/powerpc/platforms/85xx/smp.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
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+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -0,0 +1,258 @@
+/*
+ * Author: Andy Fleming <afleming@freescale.com>
+ * Kumar Gala <galak@kernel.crashing.org>
+ *
+ * Copyright 2006-2008, 2011 Freescale Semiconductor Inc.
+ *
+ * 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; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/kexec.h>
+#include <linux/highmem.h>
+
+#include <asm/machdep.h>
+#include <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/mpic.h>
+#include <asm/cacheflush.h>
+#include <asm/dbell.h>
+
+#include <sysdev/fsl_soc.h>
+#include <sysdev/mpic.h>
+#include "smp.h"
+
+extern void __early_start(void);
+
+#define BOOT_ENTRY_ADDR_UPPER 0
+#define BOOT_ENTRY_ADDR_LOWER 1
+#define BOOT_ENTRY_R3_UPPER 2
+#define BOOT_ENTRY_R3_LOWER 3
+#define BOOT_ENTRY_RESV 4
+#define BOOT_ENTRY_PIR 5
+#define BOOT_ENTRY_R6_UPPER 6
+#define BOOT_ENTRY_R6_LOWER 7
+#define NUM_BOOT_ENTRY 8
+#define SIZE_BOOT_ENTRY (NUM_BOOT_ENTRY * sizeof(u32))
+
+static int __init
+smp_85xx_kick_cpu(int nr)
+{
+ unsigned long flags;
+ const u64 *cpu_rel_addr;
+ __iomem u32 *bptr_vaddr;
+ struct device_node *np;
+ int n = 0, hw_cpu = get_hard_smp_processor_id(nr);
+ int ioremappable;
+
+ WARN_ON(nr < 0 || nr >= NR_CPUS);
+ WARN_ON(hw_cpu < 0 || hw_cpu >= NR_CPUS);
+
+ pr_debug("smp_85xx_kick_cpu: kick CPU #%d\n", nr);
+
+ np = of_get_cpu_node(nr, NULL);
+ cpu_rel_addr = of_get_property(np, "cpu-release-addr", NULL);
+
+ if (cpu_rel_addr == NULL) {
+ printk(KERN_ERR "No cpu-release-addr for cpu %d\n", nr);
+ return -ENOENT;
+ }
+
+ /*
+ * A secondary core could be in a spinloop in the bootpage
+ * (0xfffff000), somewhere in highmem, or somewhere in lowmem.
+ * The bootpage and highmem can be accessed via ioremap(), but
+ * we need to directly access the spinloop if its in lowmem.
+ */
+ ioremappable = *cpu_rel_addr > virt_to_phys(high_memory);
+
+ /* Map the spin table */
+ if (ioremappable)
+ bptr_vaddr = ioremap(*cpu_rel_addr, SIZE_BOOT_ENTRY);
+ else
+ bptr_vaddr = phys_to_virt(*cpu_rel_addr);
+
+ local_irq_save(flags);
+
+ out_be32(bptr_vaddr + BOOT_ENTRY_PIR, hw_cpu);
+#ifdef CONFIG_PPC32
+ out_be32(bptr_vaddr + BOOT_ENTRY_ADDR_LOWER, __pa(__early_start));
+
+ if (!ioremappable)
+ flush_dcache_range((ulong)bptr_vaddr,
+ (ulong)(bptr_vaddr + SIZE_BOOT_ENTRY));
+
+ /* Wait a bit for the CPU to ack. */
+ while ((__secondary_hold_acknowledge != hw_cpu) && (++n < 1000))
+ mdelay(1);
+#else
+ smp_generic_kick_cpu(nr);
+
+ out_be64((u64 *)(bptr_vaddr + BOOT_ENTRY_ADDR_UPPER),
+ __pa((u64)*((unsigned long long *) generic_secondary_smp_init)));
+
+ if (!ioremappable)
+ flush_dcache_range((ulong)bptr_vaddr,
+ (ulong)(bptr_vaddr + SIZE_BOOT_ENTRY));
+#endif
+
+ local_irq_restore(flags);
+
+ if (ioremappable)
+ iounmap(bptr_vaddr);
+
+ pr_debug("waited %d msecs for CPU #%d.\n", n, nr);
+
+ return 0;
+}
+
+struct smp_ops_t smp_85xx_ops = {
+ .kick_cpu = smp_85xx_kick_cpu,
+#ifdef CONFIG_KEXEC
+ .give_timebase = smp_generic_give_timebase,
+ .take_timebase = smp_generic_take_timebase,
+#endif
+};
+
+#ifdef CONFIG_KEXEC
+atomic_t kexec_down_cpus = ATOMIC_INIT(0);
+
+void mpc85xx_smp_kexec_cpu_down(int crash_shutdown, int secondary)
+{
+ local_irq_disable();
+
+ if (secondary) {
+ atomic_inc(&kexec_down_cpus);
+ /* loop forever */
+ while (1);
+ }
+}
+
+static void mpc85xx_smp_kexec_down(void *arg)
+{
+ if (ppc_md.kexec_cpu_down)
+ ppc_md.kexec_cpu_down(0,1);
+}
+
+static void map_and_flush(unsigned long paddr)
+{
+ struct page *page = pfn_to_page(paddr >> PAGE_SHIFT);
+ unsigned long kaddr = (unsigned long)kmap(page);
+
+ flush_dcache_range(kaddr, kaddr + PAGE_SIZE);
+ kunmap(page);
+}
+
+/**
+ * Before we reset the other cores, we need to flush relevant cache
+ * out to memory so we don't get anything corrupted, some of these flushes
+ * are performed out of an overabundance of caution as interrupts are not
+ * disabled yet and we can switch cores
+ */
+static void mpc85xx_smp_flush_dcache_kexec(struct kimage *image)
+{
+ kimage_entry_t *ptr, entry;
+ unsigned long paddr;
+ int i;
+
+ if (image->type == KEXEC_TYPE_DEFAULT) {
+ /* normal kexec images are stored in temporary pages */
+ for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
+ ptr = (entry & IND_INDIRECTION) ?
+ phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
+ if (!(entry & IND_DESTINATION)) {
+ map_and_flush(entry);
+ }
+ }
+ /* flush out last IND_DONE page */
+ map_and_flush(entry);
+ } else {
+ /* crash type kexec images are copied to the crash region */
+ for (i = 0; i < image->nr_segments; i++) {
+ struct kexec_segment *seg = &image->segment[i];
+ for (paddr = seg->mem; paddr < seg->mem + seg->memsz;
+ paddr += PAGE_SIZE) {
+ map_and_flush(paddr);
+ }
+ }
+ }
+
+ /* also flush the kimage struct to be passed in as well */
+ flush_dcache_range((unsigned long)image,
+ (unsigned long)image + sizeof(*image));
+}
+
+static void mpc85xx_smp_machine_kexec(struct kimage *image)
+{
+ int timeout = INT_MAX;
+ int i, num_cpus = num_present_cpus();
+
+ mpc85xx_smp_flush_dcache_kexec(image);
+
+ if (image->type == KEXEC_TYPE_DEFAULT)
+ smp_call_function(mpc85xx_smp_kexec_down, NULL, 0);
+
+ while ( (atomic_read(&kexec_down_cpus) != (num_cpus - 1)) &&
+ ( timeout > 0 ) )
+ {
+ timeout--;
+ }
+
+ if ( !timeout )
+ printk(KERN_ERR "Unable to bring down secondary cpu(s)");
+
+ for_each_online_cpu(i)
+ {
+ if ( i == smp_processor_id() ) continue;
+ mpic_reset_core(i);
+ }
+
+ default_machine_kexec(image);
+}
+#endif /* CONFIG_KEXEC */
+
+static void __init
+smp_85xx_setup_cpu(int cpu_nr)
+{
+ if (smp_85xx_ops.probe == smp_mpic_probe)
+ mpic_setup_this_cpu();
+
+ if (cpu_has_feature(CPU_FTR_DBELL))
+ doorbell_setup_this_cpu();
+}
+
+void __init mpc85xx_smp_init(void)
+{
+ struct device_node *np;
+
+ smp_85xx_ops.setup_cpu = smp_85xx_setup_cpu;
+
+ np = of_find_node_by_type(NULL, "open-pic");
+ if (np) {
+ smp_85xx_ops.probe = smp_mpic_probe;
+ smp_85xx_ops.message_pass = smp_mpic_message_pass;
+ }
+
+ if (cpu_has_feature(CPU_FTR_DBELL)) {
+ /*
+ * If left NULL, .message_pass defaults to
+ * smp_muxed_ipi_message_pass
+ */
+ smp_85xx_ops.message_pass = NULL;
+ smp_85xx_ops.cause_ipi = doorbell_cause_ipi;
+ }
+
+ smp_ops = &smp_85xx_ops;
+
+#ifdef CONFIG_KEXEC
+ ppc_md.kexec_cpu_down = mpc85xx_smp_kexec_cpu_down;
+ ppc_md.machine_kexec = mpc85xx_smp_machine_kexec;
+#endif
+}