diff options
Diffstat (limited to 'arch/powerpc/platforms/85xx/smp.c')
-rw-r--r-- | arch/powerpc/platforms/85xx/smp.c | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c new file mode 100644 index 00000000..ff424904 --- /dev/null +++ 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 +} |