ARM: vfp: Use cpu pm notifiers to save vfp state

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 <ccross@android.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-and-Acked-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Vishwanath BS <vishwanath.bs@ti.com>
This commit is contained in:
Colin Cross 2011-02-10 02:08:32 -08:00 committed by Santosh Shilimkar
parent 254056f3b1
commit 746a9d1963
1 changed files with 21 additions and 8 deletions

View File

@ -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