cpu_suspend() has a weird calling method which makes it only possible to call from assembly code: it returns with a modified stack pointer to finish the suspend, but on resume, it 'returns' via a provided pointer. We can make cpu_suspend() appear to be a normal function merely by swapping the resume pointer argument and the link register. Do so, and update all callers to take account of this more traditional behaviour. Acked-by: Frank Hofmann <frank.hofmann@xxxxxxxxxx> Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> --- arch/arm/include/asm/system.h | 2 ++ arch/arm/kernel/sleep.S | 10 ++++------ arch/arm/mach-exynos4/sleep.S | 7 +++---- arch/arm/mach-pxa/sleep.S | 13 ++++++++++--- arch/arm/mach-s3c64xx/sleep.S | 9 +++------ arch/arm/mach-s5pv210/sleep.S | 7 +++---- arch/arm/mach-sa1100/sleep.S | 13 +++---------- arch/arm/plat-s3c24xx/sleep.S | 10 +++------- 8 files changed, 31 insertions(+), 40 deletions(-) diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h index 832888d..50be605 100644 --- a/arch/arm/include/asm/system.h +++ b/arch/arm/include/asm/system.h @@ -106,6 +106,8 @@ extern void __show_regs(struct pt_regs *); extern int cpu_architecture(void); extern void cpu_init(void); +extern void cpu_suspend(int, long, unsigned long, void (*)(unsigned long)); +extern void cpu_resume(void); void arm_machine_restart(char mode, const char *cmd); extern void (*arm_pm_restart)(char str, const char *cmd); diff --git a/arch/arm/kernel/sleep.S b/arch/arm/kernel/sleep.S index b924bcc..e062677 100644 --- a/arch/arm/kernel/sleep.S +++ b/arch/arm/kernel/sleep.S @@ -11,13 +11,11 @@ * Save CPU state for a suspend * r1 = v:p offset * r2 = suspend function arg0 - * r3 = virtual return function - * Note: sp is decremented to allocate space for CPU state on stack - * r0-r3,ip,lr corrupted + * r3 = suspend function + * Note: does not return until system resumes */ ENTRY(cpu_suspend) - stmfd sp!, {r3} - stmfd sp!, {r4 - r11} + stmfd sp!, {r4 - r11, lr} #ifdef MULTI_CPU ldr r10, =processor ldr r5, [r10, #CPU_SLEEP_SIZE] @ size of CPU sleep state @@ -33,7 +31,7 @@ ENTRY(cpu_suspend) 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, lr} @ save suspend func arg and pointer + stmfd sp!, {r2, r3} @ save suspend func arg and pointer #ifdef CONFIG_SMP ALT_SMP(mrc p15, 0, lr, c0, c0, 5) ALT_UP(mov lr, #0) diff --git a/arch/arm/mach-exynos4/sleep.S b/arch/arm/mach-exynos4/sleep.S index 6b62425..d9a2287 100644 --- a/arch/arm/mach-exynos4/sleep.S +++ b/arch/arm/mach-exynos4/sleep.S @@ -42,16 +42,15 @@ ENTRY(s3c_cpu_save) stmfd sp!, { r3 - r12, lr } - ldr r3, =resume_with_mmu + adr r3, BSYM(exynos4_finish_suspend) bl cpu_suspend + ldmfd sp!, { r3 - r12, pc } +exynos4_finish_suspend: ldr r0, =pm_cpu_sleep ldr r0, [ r0 ] mov pc, r0 -resume_with_mmu: - ldmfd sp!, { r3 - r12, pc } - .ltorg /* diff --git a/arch/arm/mach-pxa/sleep.S b/arch/arm/mach-pxa/sleep.S index 613ddfa..3a67887 100644 --- a/arch/arm/mach-pxa/sleep.S +++ b/arch/arm/mach-pxa/sleep.S @@ -35,9 +35,11 @@ ENTRY(pxa3xx_cpu_suspend) #endif stmfd sp!, {r2 - r12, lr} @ save registers on stack mov r1, r0 - ldr r3, =pxa_cpu_resume @ resume function + adr r3, BSYM(pxa3xx_finish_suspend) bl cpu_suspend + b pxa_cpu_resume +pxa3xx_finish_suspend: mov r0, #0x06 @ S2D3C4 mode mcr p14, 0, r0, c7, c0, 0 @ enter sleep @@ -60,9 +62,11 @@ ENTRY(pxa27x_cpu_suspend) #endif stmfd sp!, {r2 - r12, lr} @ save registers on stack mov r2, r0 @ save sleep mode - ldr r3, =pxa_cpu_resume @ resume function + adr r3, BSYM(pxa27x_finish_suspend) bl cpu_suspend + b pxa_cpu_resume +pxa27x_finish_suspend: @ Put the processor to sleep @ (also workaround for sighting 28071) @@ -110,8 +114,11 @@ ENTRY(pxa27x_cpu_suspend) ENTRY(pxa25x_cpu_suspend) stmfd sp!, {r2 - r12, lr} @ save registers on stack mov r2, r0 @ save sleep mode - ldr r3, =pxa_cpu_resume @ resume function + adr r3, BSYM(pxa25x_finish_suspend) bl cpu_suspend + b pxa_cpu_resume + +pxa25x_finish_suspend: @ prepare value for sleep mode mov r1, r0 @ sleep mode diff --git a/arch/arm/mach-s3c64xx/sleep.S b/arch/arm/mach-s3c64xx/sleep.S index 1f87732..dc4f582 100644 --- a/arch/arm/mach-s3c64xx/sleep.S +++ b/arch/arm/mach-s3c64xx/sleep.S @@ -36,18 +36,15 @@ ENTRY(s3c_cpu_save) stmfd sp!, { r4 - r12, lr } - ldr r3, =resume_with_mmu + adr r3, BSYM(s3c64xx_finish_suspend) bl cpu_suspend + ldmfd sp!, { r4 - r12, pc } +s3c64xx_finish_suspend: @@ call final suspend code ldr r0, =pm_cpu_sleep ldr pc, [r0] - @@ return to the caller, after the MMU is turned on. - @@ restore the last bits of the stack and return. -resume_with_mmu: - ldmfd sp!, { r4 - r12, pc } @ return, from sp from s3c_cpu_save - /* Sleep magic, the word before the resume entry point so that the * bootloader can check for a resumeable image. */ diff --git a/arch/arm/mach-s5pv210/sleep.S b/arch/arm/mach-s5pv210/sleep.S index a3d6494..1182fc8 100644 --- a/arch/arm/mach-s5pv210/sleep.S +++ b/arch/arm/mach-s5pv210/sleep.S @@ -41,16 +41,15 @@ ENTRY(s3c_cpu_save) stmfd sp!, { r3 - r12, lr } - ldr r3, =resume_with_mmu + adr r3, BSYM(s5pv210_finish_suspend) bl cpu_suspend + ldmfd sp!, { r3 - r12, pc } +s5pv210_finish_suspend: ldr r0, =pm_cpu_sleep ldr r0, [ r0 ] mov pc, r0 -resume_with_mmu: - ldmfd sp!, { r3 - r12, pc } - .ltorg /* sleep magic, to allow the bootloader to check for an valid diff --git a/arch/arm/mach-sa1100/sleep.S b/arch/arm/mach-sa1100/sleep.S index 122ab3c..f3fe397 100644 --- a/arch/arm/mach-sa1100/sleep.S +++ b/arch/arm/mach-sa1100/sleep.S @@ -31,9 +31,11 @@ ENTRY(sa1100_cpu_suspend) stmfd sp!, {r4 - r12, lr} @ save registers on stack mov r1, r0 - ldr r3, =sa1100_cpu_resume @ return function + adr r3, BSYM(sa1100_finish_suspend) bl cpu_suspend + ldmfd sp!, {r4 - r12, pc} @ return to caller +sa1100_finish_suspend: @ disable clock switching mcr p15, 0, r1, c15, c2, 2 @@ -139,12 +141,3 @@ sa1110_sdram_controller_fix: str r13, [r12] 20: b 20b @ loop waiting for sleep - -/* - * cpu_sa1100_resume() - * - * entry point from bootloader into kernel during resume - */ - .align 5 -sa1100_cpu_resume: - ldmfd sp!, {r4 - r12, pc} @ return to caller diff --git a/arch/arm/plat-s3c24xx/sleep.S b/arch/arm/plat-s3c24xx/sleep.S index fd7032f..f822e62 100644 --- a/arch/arm/plat-s3c24xx/sleep.S +++ b/arch/arm/plat-s3c24xx/sleep.S @@ -49,21 +49,17 @@ ENTRY(s3c_cpu_save) stmfd sp!, { r4 - r12, lr } - ldr r3, =resume_with_mmu + adr r3, BSYM(s3c24xx_finish_suspend) bl cpu_suspend + ldmfd sp!, { r4 - r12, pc } +s3c24xx_finish_suspend: @@ jump to final code to send system to sleep ldr r0, =pm_cpu_sleep @@ldr pc, [ r0 ] ldr r0, [ r0 ] mov pc, r0 - @@ return to the caller, after having the MMU - @@ turned on, this restores the last bits from the - @@ stack -resume_with_mmu: - ldmfd sp!, { r4 - r12, pc } - .ltorg /* sleep magic, to allow the bootloader to check for an valid -- 1.7.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html