[ARM] 3802/1: S3C24XX: PM tidy up cache flushing

Change to using flush_cache_all() in pm.c and
also remove the need to flush the cache in the
PM code.

This changes the sleep.S code to have an entry
to store the registers for resume, and then a
second entry (after the caches are cleaned)
to do the suspend and resume.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 22 insertions, 9 deletions

diff --git a/arch/arm/mach-s3c2410/sleep.S b/arch/arm/mach-s3c2410/sleep.S
index a7561a79fc82..e977aa1ffe18 100644
--- a/arch/arm/mach-s3c2410/sleep.S
+++ b/arch/arm/mach-s3c2410/sleep.S
@@ -41,15 +41,25 @@
 
         .text
 
-        /* s3c2410_cpu_suspend
+        /* s3c2410_cpu_save
          *
-         * put the cpu into sleep mode
+         * save enough of the CPU state to allow us to re-start
+         * pm.c code. as we store items like the sp/lr, we will
+         * end up returning from this function when the cpu resumes
+         * so the return value is set to mark this.
+         *
+         * This arangement means we avoid having to flush the cache
+         * from this code.
          *
          * entry:
-         *      r0 = sleep save block
+         *      r0 = pointer to save block
+         *
+         * exit:
+         *      r0 = 0 => we stored everything
+         *           1 => resumed from sleep
         */
 
-ENTRY(s3c2410_cpu_suspend)
+ENTRY(s3c2410_cpu_save)
         stmfd   sp!, { r4 - r12, lr }
 
         @@ store co-processor registers
@@ -62,13 +72,15 @@ ENTRY(s3c2410_cpu_suspend)
 
         stmia   r0, { r4 - r13 }
 
-        @@ flush the caches to ensure everything is back out to
-        @@ SDRAM before the core powers down
+        mov     r0, #0
+        ldmfd   sp, { r4 - r12, pc }
 
-#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
-        bl      arm920_flush_kern_cache_all
-#endif
+        /* s3c2410_cpu_suspend
+         *
+         * put the cpu into sleep mode
+        */
 
+ENTRY(s3c2410_cpu_suspend)
         @@ prepare cpu to sleep
 
         ldr     r4, =S3C2410_REFRESH
@@ -100,6 +112,7 @@ s3c2410_do_sleep:
         @@ turned on, this restores the last bits from the
         @@ stack
 resume_with_mmu:
+        mov     r0, #1
         ldmfd   sp!, { r4 - r12, pc }
 
         .ltorg