[PATCH v2 4/5] ARM: vfp: Use cpu pm notifiers to save vfp state
From: Santosh Shilimkar <hidden>
Date: 2011-09-03 14:40:27
Also in:
lkml
Subsystem:
arm port, arm/vfp support, the rest · Maintainers:
Russell King, Linus Torvalds
From: Colin Cross <redacted> When the cpu is powered down in a low power mode, the vfp registers may be reset. This patch uses CPU_PM_ENTER and CPU_PM_EXIT notifiers to save and restore the cpu's vfp registers. Signed-off-by: Colin Cross <redacted> [santosh.shilimkar at ti.com: Rebased against 3.1-rc4, resolved the conflicts] Signed-off-by: Santosh Shilimkar <redacted> --- arch/arm/vfp/vfpmodule.c | 29 +++++++++++++++++++++-------- 1 files changed, 21 insertions(+), 8 deletions(-)
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index 79bcb43..fe4b60b 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c@@ -11,6 +11,7 @@ #include <linux/module.h> #include <linux/types.h> #include <linux/cpu.h> +#include <linux/cpu_pm.h> #include <linux/kernel.h> #include <linux/notifier.h> #include <linux/signal.h>
@@ -436,9 +437,7 @@ static void vfp_enable(void *unused) set_copro_access(access | CPACC_FULL(10) | CPACC_FULL(11)); } -#ifdef CONFIG_PM -#include <linux/syscore_ops.h> - +#ifdef CONFIG_CPU_PM static int vfp_pm_suspend(void) { struct thread_info *ti = current_thread_info();
@@ -468,19 +467,33 @@ static void vfp_pm_resume(void) fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN); } -static struct syscore_ops vfp_pm_syscore_ops = { - .suspend = vfp_pm_suspend, - .resume = vfp_pm_resume, +static int vfp_cpu_pm_notifier(struct notifier_block *self, unsigned long cmd, + void *v) +{ + switch (cmd) { + case CPU_PM_ENTER: + vfp_pm_suspend(); + break; + case CPU_PM_ENTER_FAILED: + case CPU_PM_EXIT: + vfp_pm_resume(); + break; + } + return NOTIFY_OK; +} + +static struct notifier_block vfp_cpu_pm_notifier_block = { + .notifier_call = vfp_cpu_pm_notifier, }; static void vfp_pm_init(void) { - register_syscore_ops(&vfp_pm_syscore_ops); + cpu_pm_register_notifier(&vfp_cpu_pm_notifier_block); } #else static inline void vfp_pm_init(void) { } -#endif /* CONFIG_PM */ +#endif /* CONFIG_CPU_PM */ /* * Ensure that the VFP state stored in 'thread->vfpstate' is up to date
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