ARM: pm: allow generic sleep code to be used with SMP CPU idle

Allow the generic sleep code to be used with SMP CPU idle by storing
N CPU stack pointers rather than just one.  Tested on Assabet and
Tegra 2.

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

1 files changed, 26 insertions, 1 deletions

diff --git a/arch/arm/kernel/sleep.S b/arch/arm/kernel/sleep.S
index 2ba17946619e..bfad698a02e7 100644
--- a/arch/arm/kernel/sleep.S
+++ b/arch/arm/kernel/sleep.S
@@ -1,4 +1,5 @@
 #include <linux/linkage.h>
+#include <linux/threads.h>
 #include <asm/asm-offsets.h>
 #include <asm/assembler.h>
 #include <asm/glue-cache.h>
@@ -26,7 +27,14 @@ ENTRY(cpu_suspend)
         stmfd   sp!, {r1, r2, r3, ip}   @ save v:p, virt SP, retfn, phys resume fn
         ldr     r3, =sleep_save_sp
         add     r2, sp, r1              @ convert SP to phys
+#ifdef CONFIG_SMP
+        ALT_SMP(mrc p15, 0, lr, c0, c0, 5)
+        ALT_UP(mov lr, #0)
+        and     lr, lr, #15
+        str     r2, [r3, lr, lsl #2]    @ save phys SP
+#else
         str     r2, [r3]                @ save phys SP
+#endif
         mov     lr, pc
         ldr     pc, [r10, #CPU_DO_SUSPEND] @ save CPU state
 #else
@@ -37,7 +45,14 @@ ENTRY(cpu_suspend)
         stmfd   sp!, {r1, r2, r3}       @ save v:p, virt SP, return fn
         ldr     r3, =sleep_save_sp
         add     r2, sp, r1              @ convert SP to phys
+#ifdef CONFIG_SMP
+        ALT_SMP(mrc p15, 0, lr, c0, c0, 5)
+        ALT_UP(mov lr, #0)
+        and     lr, lr, #15
+        str     r2, [r3, lr, lsl #2]    @ save phys SP
+#else
         str     r2, [r3]                @ save phys SP
+#endif
         bl      cpu_do_suspend
 #endif
 
@@ -95,7 +110,15 @@ ENDPROC(cpu_resume_after_mmu)
         .data
         .align
 ENTRY(cpu_resume)
+#ifdef CONFIG_SMP
+        adr     r0, sleep_save_sp
+        ALT_SMP(mrc p15, 0, r1, c0, c0, 5)
+        ALT_UP(mov r1, #0)
+        and     r1, r1, #15
+        ldr     r0, [r0, r1, lsl #2]    @ stack phys addr
+#else
         ldr     r0, sleep_save_sp       @ stack phys addr
+#endif
         msr     cpsr_c, #PSR_I_BIT | PSR_F_BIT | SVC_MODE @ set SVC, irqs off
 #ifdef MULTI_CPU
         ldmia   r0!, {r1, sp, lr, pc}   @ load v:p, stack, return fn, resume fn
@@ -106,4 +129,6 @@ ENTRY(cpu_resume)
 ENDPROC(cpu_resume)
 
 sleep_save_sp:
-        .word   0                               @ preserve stack phys ptr here
+        .rept   CONFIG_NR_CPUS
+        .long   0                               @ preserve stack phys ptr here
+        .endr