[ARM] pxa: skip registers saving/restoring if entering standby mode
registers are retained during standby mode, thus it's not necessary
to save/restore and checksum
Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-pxa/pm.c b/arch/arm/mach-pxa/pm.c
index a941c71..039194c 100644
--- a/arch/arm/mach-pxa/pm.c
+++ b/arch/arm/mach-pxa/pm.c
@@ -38,34 +38,37 @@
iwmmxt_task_disable(NULL);
#endif
- pxa_cpu_pm_fns->save(sleep_save);
+ /* skip registers saving for standby */
+ if (state != PM_SUSPEND_STANDBY) {
+ pxa_cpu_pm_fns->save(sleep_save);
+ /* before sleeping, calculate and save a checksum */
+ for (i = 0; i < pxa_cpu_pm_fns->save_size - 1; i++)
+ sleep_save_checksum += sleep_save[i];
+ }
/* Clear sleep reset status */
RCSR = RCSR_SMR;
- /* before sleeping, calculate and save a checksum */
- for (i = 0; i < pxa_cpu_pm_fns->save_size - 1; i++)
- sleep_save_checksum += sleep_save[i];
-
/* *** go zzz *** */
pxa_cpu_pm_fns->enter(state);
cpu_init();
- /* after sleeping, validate the checksum */
- for (i = 0; i < pxa_cpu_pm_fns->save_size - 1; i++)
- checksum += sleep_save[i];
+ if (state != PM_SUSPEND_STANDBY) {
+ /* after sleeping, validate the checksum */
+ for (i = 0; i < pxa_cpu_pm_fns->save_size - 1; i++)
+ checksum += sleep_save[i];
- /* if invalid, display message and wait for a hardware reset */
- if (checksum != sleep_save_checksum) {
+ /* if invalid, display message and wait for a hardware reset */
+ if (checksum != sleep_save_checksum) {
#ifdef CONFIG_ARCH_LUBBOCK
- LUB_HEXLED = 0xbadbadc5;
+ LUB_HEXLED = 0xbadbadc5;
#endif
- while (1)
- pxa_cpu_pm_fns->enter(state);
+ while (1)
+ pxa_cpu_pm_fns->enter(state);
+ }
+ pxa_cpu_pm_fns->restore(sleep_save);
}
- pxa_cpu_pm_fns->restore(sleep_save);
-
pr_debug("*** made it back from resume\n");
return 0;