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authorRussell King <rmk+kernel@arm.linux.org.uk>2011-09-22 22:39:23 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2011-09-22 22:39:23 +0100
commitb0a37dca72a05b7b579f288d8a67afeed96bffa5 (patch)
treea3057a3debd078f569e90e709d7b320006d8cb32 /arch/arm/kernel
parentf70cac8d9c7125f83048f8b3d1c60f5a041a165c (diff)
parent8e6f83bbdf770014c070c5a41c8e89617cb2a66b (diff)
downloadop-kernel-dev-b0a37dca72a05b7b579f288d8a67afeed96bffa5.zip
op-kernel-dev-b0a37dca72a05b7b579f288d8a67afeed96bffa5.tar.gz
Merge branch 'pm' into devel-stable
Diffstat (limited to 'arch/arm/kernel')
-rw-r--r--arch/arm/kernel/Makefile2
-rw-r--r--arch/arm/kernel/sleep.S85
-rw-r--r--arch/arm/kernel/suspend.c72
3 files changed, 100 insertions, 59 deletions
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index af32e46..8fa83f5 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 dc902f2..020e99c 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 0000000..93a22d2
--- /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);
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