Merge branch 'pm' into devel-stable

3 files changed, 100 insertions, 59 deletions

diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index af32e466e1c..8fa83f54c96 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -29,7 +29,7 @@ obj-$(CONFIG_MODULES)		+= armksyms.o module.o
 obj-$(CONFIG_ARTHUR)            += arthur.o
 obj-$(CONFIG_ISA_DMA)           += dma-isa.o
 obj-$(CONFIG_PCI)               += bios32.o isa.o
-obj-$(CONFIG_PM_SLEEP)          += sleep.o
+obj-$(CONFIG_PM_SLEEP)          += sleep.o suspend.o
 obj-$(CONFIG_HAVE_SCHED_CLOCK)  += sched_clock.o
 obj-$(CONFIG_SMP)               += smp.o smp_tlb.o
 obj-$(CONFIG_HAVE_ARM_SCU)      += smp_scu.o
diff --git a/arch/arm/kernel/sleep.S b/arch/arm/kernel/sleep.S
index dc902f2c684..020e99c845e 100644
--- a/arch/arm/kernel/sleep.S
+++ b/arch/arm/kernel/sleep.S
@@ -8,92 +8,61 @@
         .text
 
 /*
- * Save CPU state for a suspend
- *  r1 = v:p offset
- *  r2 = suspend function arg0
- *  r3 = suspend function
+ * Save CPU state for a suspend.  This saves the CPU general purpose
+ * registers, and allocates space on the kernel stack to save the CPU
+ * specific registers and some other data for resume.
+ *  r0 = suspend function arg0
+ *  r1 = suspend function
  */
 ENTRY(__cpu_suspend)
         stmfd   sp!, {r4 - r11, lr}
 #ifdef MULTI_CPU
         ldr     r10, =processor
-        ldr     r5, [r10, #CPU_SLEEP_SIZE] @ size of CPU sleep state
-        ldr     ip, [r10, #CPU_DO_RESUME] @ virtual resume function
+        ldr     r4, [r10, #CPU_SLEEP_SIZE] @ size of CPU sleep state
 #else
-        ldr     r5, =cpu_suspend_size
-        ldr     ip, =cpu_do_resume
+        ldr     r4, =cpu_suspend_size
 #endif
-        mov     r6, sp                  @ current virtual SP
-        sub     sp, sp, r5              @ allocate CPU state on stack
-        mov     r0, sp                  @ save pointer to CPU save block
-        add     ip, ip, r1              @ convert resume fn to phys
-        stmfd   sp!, {r1, r6, ip}       @ save v:p, virt SP, phys resume fn
-        ldr     r5, =sleep_save_sp
-        add     r6, sp, r1              @ convert SP to phys
-        stmfd   sp!, {r2, r3}           @ save suspend func arg and pointer
+        mov     r5, sp                  @ current virtual SP
+        add     r4, r4, #12             @ Space for pgd, virt sp, phys resume fn
+        sub     sp, sp, r4              @ allocate CPU state on stack
+        stmfd   sp!, {r0, r1}           @ save suspend func arg and pointer
+        add     r0, sp, #8              @ save pointer to save block
+        mov     r1, r4                  @ size of save block
+        mov     r2, r5                  @ virtual SP
+        ldr     r3, =sleep_save_sp
 #ifdef CONFIG_SMP
         ALT_SMP(mrc p15, 0, lr, c0, c0, 5)
         ALT_UP(mov lr, #0)
         and     lr, lr, #15
-        str     r6, [r5, lr, lsl #2]    @ save phys SP
-#else
-        str     r6, [r5]                @ save phys SP
-#endif
-#ifdef MULTI_CPU
-        mov     lr, pc
-        ldr     pc, [r10, #CPU_DO_SUSPEND] @ save CPU state
-#else
-        bl      cpu_do_suspend
-#endif
-
-        @ flush data cache
-#ifdef MULTI_CACHE
-        ldr     r10, =cpu_cache
-        mov     lr, pc
-        ldr     pc, [r10, #CACHE_FLUSH_KERN_ALL]
-#else
-        bl      __cpuc_flush_kern_all
+        add     r3, r3, lr, lsl #2
 #endif
+        bl      __cpu_suspend_save
         adr     lr, BSYM(cpu_suspend_abort)
         ldmfd   sp!, {r0, pc}           @ call suspend fn
 ENDPROC(__cpu_suspend)
         .ltorg
 
 cpu_suspend_abort:
-        ldmia   sp!, {r1 - r3}          @ pop v:p, virt SP, phys resume fn
+        ldmia   sp!, {r1 - r3}          @ pop phys pgd, virt SP, phys resume fn
+        teq     r0, #0
+        moveq   r0, #1                  @ force non-zero value
         mov     sp, r2
         ldmfd   sp!, {r4 - r11, pc}
 ENDPROC(cpu_suspend_abort)
 
 /*
  * r0 = control register value
- * r1 = v:p offset (preserved by cpu_do_resume)
- * r2 = phys page table base
- * r3 = L1 section flags
  */
+        .align  5
 ENTRY(cpu_resume_mmu)
-        adr     r4, cpu_resume_turn_mmu_on
-        mov     r4, r4, lsr #20
-        orr     r3, r3, r4, lsl #20
-        ldr     r5, [r2, r4, lsl #2]    @ save old mapping
-        str     r3, [r2, r4, lsl #2]    @ setup 1:1 mapping for mmu code
-        sub     r2, r2, r1
         ldr     r3, =cpu_resume_after_mmu
-        bic     r1, r0, #CR_C           @ ensure D-cache is disabled
-        b       cpu_resume_turn_mmu_on
-ENDPROC(cpu_resume_mmu)
-        .ltorg
-        .align  5
-cpu_resume_turn_mmu_on:
-        mcr     p15, 0, r1, c1, c0, 0   @ turn on MMU, I-cache, etc
-        mrc     p15, 0, r1, c0, c0, 0   @ read id reg
-        mov     r1, r1
-        mov     r1, r1
+        mcr     p15, 0, r0, c1, c0, 0   @ turn on MMU, I-cache, etc
+        mrc     p15, 0, r0, c0, c0, 0   @ read id reg
+        mov     r0, r0
+        mov     r0, r0
         mov     pc, r3                  @ jump to virtual address
-ENDPROC(cpu_resume_turn_mmu_on)
+ENDPROC(cpu_resume_mmu)
 cpu_resume_after_mmu:
-        str     r5, [r2, r4, lsl #2]    @ restore old mapping
-        mcr     p15, 0, r0, c1, c0, 0   @ turn on D-cache
         bl      cpu_init                @ restore the und/abt/irq banked regs
         mov     r0, #0                  @ return zero on success
         ldmfd   sp!, {r4 - r11, pc}
@@ -119,7 +88,7 @@ ENTRY(cpu_resume)
         ldr     r0, sleep_save_sp       @ stack phys addr
 #endif
         setmode PSR_I_BIT | PSR_F_BIT | SVC_MODE, r1  @ set SVC, irqs off
-        @ load v:p, stack, resume fn
+        @ load phys pgd, stack, resume fn
   ARM(  ldmia   r0!, {r1, sp, pc}       )
 THUMB(  ldmia   r0!, {r1, r2, r3}       )
 THUMB(  mov     sp, r2                  )
diff --git a/arch/arm/kernel/suspend.c b/arch/arm/kernel/suspend.c
new file mode 100644
index 00000000000..93a22d282c1
--- /dev/null
+++ b/arch/arm/kernel/suspend.c
@@ -0,0 +1,72 @@
+#include <linux/init.h>
+
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/memory.h>
+#include <asm/suspend.h>
+#include <asm/tlbflush.h>
+
+static pgd_t *suspend_pgd;
+
+extern int __cpu_suspend(unsigned long, int (*)(unsigned long));
+extern void cpu_resume_mmu(void);
+
+/*
+ * This is called by __cpu_suspend() to save the state, and do whatever
+ * flushing is required to ensure that when the CPU goes to sleep we have
+ * the necessary data available when the caches are not searched.
+ */
+void __cpu_suspend_save(u32 *ptr, u32 ptrsz, u32 sp, u32 *save_ptr)
+{
+        *save_ptr = virt_to_phys(ptr);
+
+        /* This must correspond to the LDM in cpu_resume() assembly */
+        *ptr++ = virt_to_phys(suspend_pgd);
+        *ptr++ = sp;
+        *ptr++ = virt_to_phys(cpu_do_resume);
+
+        cpu_do_suspend(ptr);
+
+        flush_cache_all();
+        outer_clean_range(*save_ptr, *save_ptr + ptrsz);
+        outer_clean_range(virt_to_phys(save_ptr),
+                          virt_to_phys(save_ptr) + sizeof(*save_ptr));
+}
+
+/*
+ * Hide the first two arguments to __cpu_suspend - these are an implementation
+ * detail which platform code shouldn't have to know about.
+ */
+int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
+{
+        struct mm_struct *mm = current->active_mm;
+        int ret;
+
+        if (!suspend_pgd)
+                return -EINVAL;
+
+        /*
+         * Provide a temporary page table with an identity mapping for
+         * the MMU-enable code, required for resuming.  On successful
+         * resume (indicated by a zero return code), we need to switch
+         * back to the correct page tables.
+         */
+        ret = __cpu_suspend(arg, fn);
+        if (ret == 0) {
+                cpu_switch_mm(mm->pgd, mm);
+                local_flush_tlb_all();
+        }
+
+        return ret;
+}
+
+static int __init cpu_suspend_init(void)
+{
+        suspend_pgd = pgd_alloc(&init_mm);
+        if (suspend_pgd) {
+                unsigned long addr = virt_to_phys(cpu_resume_mmu);
+                identity_mapping_add(suspend_pgd, addr, addr + SECTION_SIZE);
+        }
+        return suspend_pgd ? 0 : -ENOMEM;
+}
+core_initcall(cpu_suspend_init);