diff options
author | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-09-22 22:39:23 +0100 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-09-22 22:39:23 +0100 |
commit | b0a37dca72a05b7b579f288d8a67afeed96bffa5 (patch) | |
tree | a3057a3debd078f569e90e709d7b320006d8cb32 /arch/arm/kernel | |
parent | f70cac8d9c7125f83048f8b3d1c60f5a041a165c (diff) | |
parent | 8e6f83bbdf770014c070c5a41c8e89617cb2a66b (diff) |
Merge branch 'pm' into devel-stable
Diffstat (limited to 'arch/arm/kernel')
-rw-r--r-- | arch/arm/kernel/Makefile | 2 | ||||
-rw-r--r-- | arch/arm/kernel/sleep.S | 85 | ||||
-rw-r--r-- | arch/arm/kernel/suspend.c | 72 |
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); |