ARM: pm: add generic CPU suspend/resume support

This adds core support for saving and restoring CPU coprocessor
registers for suspend/resume support.  This contains support for suspend
with ARM920, ARM926, SA11x0, PXA25x, PXA27x, PXA3xx, V6 and V7 CPUs.
Tested on Assabet and Tegra 2.

Tested-by: Colin Cross <ccross@android.com>
Tested-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 37 insertions, 0 deletions

diff --git a/arch/arm/mm/proc-arm926.S b/arch/arm/mm/proc-arm926.S
index 42eb4315740b..6a4bdb2c94a7 100644
--- a/arch/arm/mm/proc-arm926.S
+++ b/arch/arm/mm/proc-arm926.S
@@ -401,6 +401,40 @@ ENTRY(cpu_arm926_set_pte_ext)
 #endif
         mov     pc, lr
 
+/* Suspend/resume support: taken from arch/arm/plat-s3c24xx/sleep.S */
+.globl  cpu_arm926_suspend_size
+.equ    cpu_arm926_suspend_size, 4 * 3
+#ifdef CONFIG_PM
+ENTRY(cpu_arm926_do_suspend)
+        stmfd   sp!, {r4 - r7, lr}
+        mrc     p15, 0, r4, c13, c0, 0  @ PID
+        mrc     p15, 0, r5, c3, c0, 0   @ Domain ID
+        mrc     p15, 0, r6, c2, c0, 0   @ TTB address
+        mrc     p15, 0, r7, c1, c0, 0   @ Control register
+        stmia   r0, {r4 - r7}
+        ldmfd   sp!, {r4 - r7, pc}
+ENDPROC(cpu_arm926_do_suspend)
+
+ENTRY(cpu_arm926_do_resume)
+        mov     ip, #0
+        mcr     p15, 0, ip, c8, c7, 0   @ invalidate I+D TLBs
+        mcr     p15, 0, ip, c7, c7, 0   @ invalidate I+D caches
+        ldmia   r0, {r4 - r7}
+        mcr     p15, 0, r4, c13, c0, 0  @ PID
+        mcr     p15, 0, r5, c3, c0, 0   @ Domain ID
+        mcr     p15, 0, r6, c2, c0, 0   @ TTB address
+        mov     r0, r7                  @ control register
+        mov     r2, r6, lsr #14         @ get TTB0 base
+        mov     r2, r2, lsl #14
+        ldr     r3, =PMD_TYPE_SECT | PMD_SECT_BUFFERABLE | \
+                     PMD_SECT_CACHEABLE | PMD_BIT4 | PMD_SECT_AP_WRITE
+        b       cpu_resume_mmu
+ENDPROC(cpu_arm926_do_resume)
+#else
+#define cpu_arm926_do_suspend   0
+#define cpu_arm926_do_resume    0
+#endif
+
         __CPUINIT
 
         .type   __arm926_setup, #function
@@ -456,6 +490,9 @@ arm926_processor_functions:
         .word   cpu_arm926_dcache_clean_area
         .word   cpu_arm926_switch_mm
         .word   cpu_arm926_set_pte_ext
+        .word   cpu_arm926_suspend_size
+        .word   cpu_arm926_do_suspend
+        .word   cpu_arm926_do_resume
         .size   arm926_processor_functions, . - arm926_processor_functions
 
         .section ".rodata"