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authorLinus Torvalds <torvalds@linux-foundation.org>2012-01-06 18:15:25 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-01-06 18:15:25 -0800
commit770e1b035dcb6ec3f8ee69dda0815dd1e220a683 (patch)
treee6d36abfdb053fbc722aea8d7e946d6d1b93c7e1 /arch/arm/kernel/process.c
parentd3d0b024348c040f0d6851e2e59fc961677d5169 (diff)
parent7b9dd47136c07ffd883aff6926c7b281e4c1eea4 (diff)
Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm
* 'for-linus' of git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm: (207 commits) ARM: 7267/1: Remove BUILD_BUG_ON from asm/bug.h ARM: 7269/1: mach-sa1100: fix sched_clock breakage ARM: 7198/1: arm/imx6: add restart support for imx6q ARM: restart: remove the now empty arch_reset() ARM: restart: remove comments about adding code to arch_reset() ARM: restart: lpc32xx & u300: remove unnecessary printk ARM: restart: plat-samsung: remove plat/reset.h and s5p_reset_hook ARM: restart: w90x900: use new restart hook ARM: restart: Versatile Express: use new restart hook ARM: restart: versatile: use new restart hook ARM: restart: u300: use new restart hook ARM: restart: tegra: use new restart hook ARM: restart: spear: use new restart hook ARM: restart: shark: use new restart hook ARM: restart: sa1100: use new restart hook ARM: 7252/1: restart: S5PV210: use new restart hook ARM: 7251/1: restart: S5PC100: use new restart hook ARM: 7250/1: restart: S5P64X0: use new restart hook ARM: 7266/1: restart: S3C64XX: use new restart hook ARM: 7265/1: restart: S3C24XX: use new restart hook ... Fix up trivial conflict in arch/arm/mm/init.c due to removal of memblock_init() clashing with the movement of the sorting of the meminfo array.
Diffstat (limited to 'arch/arm/kernel/process.c')
-rw-r--r--arch/arm/kernel/process.c77
1 files changed, 54 insertions, 23 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index e8e8fe505df..971d65c253a 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -57,7 +57,7 @@ static const char *isa_modes[] = {
"ARM" , "Thumb" , "Jazelle", "ThumbEE"
};
-extern void setup_mm_for_reboot(char mode);
+extern void setup_mm_for_reboot(void);
static volatile int hlt_counter;
@@ -92,18 +92,24 @@ static int __init hlt_setup(char *__unused)
__setup("nohlt", nohlt_setup);
__setup("hlt", hlt_setup);
-void arm_machine_restart(char mode, const char *cmd)
+extern void call_with_stack(void (*fn)(void *), void *arg, void *sp);
+typedef void (*phys_reset_t)(unsigned long);
+
+/*
+ * A temporary stack to use for CPU reset. This is static so that we
+ * don't clobber it with the identity mapping. When running with this
+ * stack, any references to the current task *will not work* so you
+ * should really do as little as possible before jumping to your reset
+ * code.
+ */
+static u64 soft_restart_stack[16];
+
+static void __soft_restart(void *addr)
{
- /* Disable interrupts first */
- local_irq_disable();
- local_fiq_disable();
+ phys_reset_t phys_reset;
- /*
- * Tell the mm system that we are going to reboot -
- * we may need it to insert some 1:1 mappings so that
- * soft boot works.
- */
- setup_mm_for_reboot(mode);
+ /* Take out a flat memory mapping. */
+ setup_mm_for_reboot();
/* Clean and invalidate caches */
flush_cache_all();
@@ -114,18 +120,35 @@ void arm_machine_restart(char mode, const char *cmd)
/* Push out any further dirty data, and ensure cache is empty */
flush_cache_all();
- /*
- * Now call the architecture specific reboot code.
- */
- arch_reset(mode, cmd);
+ /* Switch to the identity mapping. */
+ phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
+ phys_reset((unsigned long)addr);
- /*
- * Whoops - the architecture was unable to reboot.
- * Tell the user!
- */
- mdelay(1000);
- printk("Reboot failed -- System halted\n");
- while (1);
+ /* Should never get here. */
+ BUG();
+}
+
+void soft_restart(unsigned long addr)
+{
+ u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack);
+
+ /* Disable interrupts first */
+ local_irq_disable();
+ local_fiq_disable();
+
+ /* Disable the L2 if we're the last man standing. */
+ if (num_online_cpus() == 1)
+ outer_disable();
+
+ /* Change to the new stack and continue with the reset. */
+ call_with_stack(__soft_restart, (void *)addr, (void *)stack);
+
+ /* Should never get here. */
+ BUG();
+}
+
+static void null_restart(char mode, const char *cmd)
+{
}
/*
@@ -134,7 +157,7 @@ void arm_machine_restart(char mode, const char *cmd)
void (*pm_power_off)(void);
EXPORT_SYMBOL(pm_power_off);
-void (*arm_pm_restart)(char str, const char *cmd) = arm_machine_restart;
+void (*arm_pm_restart)(char str, const char *cmd) = null_restart;
EXPORT_SYMBOL_GPL(arm_pm_restart);
static void do_nothing(void *unused)
@@ -255,7 +278,15 @@ void machine_power_off(void)
void machine_restart(char *cmd)
{
machine_shutdown();
+
arm_pm_restart(reboot_mode, cmd);
+
+ /* Give a grace period for failure to restart of 1s */
+ mdelay(1000);
+
+ /* Whoops - the platform was unable to reboot. Tell the user! */
+ printk("Reboot failed -- System halted\n");
+ while (1);
}
void __show_regs(struct pt_regs *regs)