diff options
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/include/asm/suspend.h | 1 | ||||
| -rw-r--r-- | arch/arm64/kernel/sleep.S | 47 | ||||
| -rw-r--r-- | arch/arm64/kernel/suspend.c | 48 |
3 files changed, 64 insertions, 32 deletions
diff --git a/arch/arm64/include/asm/suspend.h b/arch/arm64/include/asm/suspend.h index e9c149c042e0..456d67c1f0fa 100644 --- a/arch/arm64/include/asm/suspend.h +++ b/arch/arm64/include/asm/suspend.h @@ -21,6 +21,7 @@ struct sleep_save_sp { phys_addr_t save_ptr_stash_phys; }; +extern int __cpu_suspend(unsigned long arg, int (*fn)(unsigned long)); extern void cpu_resume(void); extern int cpu_suspend(unsigned long); diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S index b1925729c692..a564b440416a 100644 --- a/arch/arm64/kernel/sleep.S +++ b/arch/arm64/kernel/sleep.S @@ -49,28 +49,39 @@ orr \dst, \dst, \mask // dst|=(aff3>>rs3) .endm /* - * Save CPU state for a suspend. This saves callee registers, and allocates - * space on the kernel stack to save the CPU specific registers + some - * other data for resume. + * Save CPU state for a suspend and execute the suspend finisher. + * On success it will return 0 through cpu_resume - ie through a CPU + * soft/hard reboot from the reset vector. + * On failure it returns the suspend finisher return value or force + * -EOPNOTSUPP if the finisher erroneously returns 0 (the suspend finisher + * is not allowed to return, if it does this must be considered failure). + * It saves callee registers, and allocates space on the kernel stack + * to save the CPU specific registers + some other data for resume. * * x0 = suspend finisher argument + * x1 = suspend finisher function pointer */ -ENTRY(__cpu_suspend) +ENTRY(__cpu_suspend_enter) stp x29, lr, [sp, #-96]! stp x19, x20, [sp,#16] stp x21, x22, [sp,#32] stp x23, x24, [sp,#48] stp x25, x26, [sp,#64] stp x27, x28, [sp,#80] + /* + * Stash suspend finisher and its argument in x20 and x19 + */ + mov x19, x0 + mov x20, x1 mov x2, sp sub sp, sp, #CPU_SUSPEND_SZ // allocate cpu_suspend_ctx - mov x1, sp + mov x0, sp /* - * x1 now points to struct cpu_suspend_ctx allocated on the stack + * x0 now points to struct cpu_suspend_ctx allocated on the stack */ - str x2, [x1, #CPU_CTX_SP] - ldr x2, =sleep_save_sp - ldr x2, [x2, #SLEEP_SAVE_SP_VIRT] + str x2, [x0, #CPU_CTX_SP] + ldr x1, =sleep_save_sp + ldr x1, [x1, #SLEEP_SAVE_SP_VIRT] #ifdef CONFIG_SMP mrs x7, mpidr_el1 ldr x9, =mpidr_hash @@ -82,11 +93,21 @@ ENTRY(__cpu_suspend) ldp w3, w4, [x9, #MPIDR_HASH_SHIFTS] ldp w5, w6, [x9, #(MPIDR_HASH_SHIFTS + 8)] compute_mpidr_hash x8, x3, x4, x5, x6, x7, x10 - add x2, x2, x8, lsl #3 + add x1, x1, x8, lsl #3 #endif - bl __cpu_suspend_finisher + bl __cpu_suspend_save + /* + * Grab suspend finisher in x20 and its argument in x19 + */ + mov x0, x19 + mov x1, x20 + /* + * We are ready for power down, fire off the suspend finisher + * in x1, with argument in x0 + */ + blr x1 /* - * Never gets here, unless suspend fails. + * Never gets here, unless suspend finisher fails. * Successful cpu_suspend should return from cpu_resume, returning * through this code path is considered an error * If the return value is set to 0 force x0 = -EOPNOTSUPP @@ -103,7 +124,7 @@ ENTRY(__cpu_suspend) ldp x27, x28, [sp, #80] ldp x29, lr, [sp], #96 ret -ENDPROC(__cpu_suspend) +ENDPROC(__cpu_suspend_enter) .ltorg /* diff --git a/arch/arm64/kernel/suspend.c b/arch/arm64/kernel/suspend.c index 55a99b9a97e0..13ad4dbb1615 100644 --- a/arch/arm64/kernel/suspend.c +++ b/arch/arm64/kernel/suspend.c @@ -9,22 +9,19 @@ #include <asm/suspend.h> #include <asm/tlbflush.h> -extern int __cpu_suspend(unsigned long); +extern int __cpu_suspend_enter(unsigned long arg, int (*fn)(unsigned long)); /* - * This is called by __cpu_suspend() to save the state, and do whatever + * This is called by __cpu_suspend_enter() 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. * - * @arg: Argument to pass to suspend operations - * @ptr: CPU context virtual address - * @save_ptr: address of the location where the context physical address - * must be saved + * ptr: CPU context virtual address + * save_ptr: address of the location where the context physical address + * must be saved */ -int __cpu_suspend_finisher(unsigned long arg, struct cpu_suspend_ctx *ptr, - phys_addr_t *save_ptr) +void notrace __cpu_suspend_save(struct cpu_suspend_ctx *ptr, + phys_addr_t *save_ptr) { - int cpu = smp_processor_id(); - *save_ptr = virt_to_phys(ptr); cpu_do_suspend(ptr); @@ -35,8 +32,6 @@ int __cpu_suspend_finisher(unsigned long arg, struct cpu_suspend_ctx *ptr, */ __flush_dcache_area(ptr, sizeof(*ptr)); __flush_dcache_area(save_ptr, sizeof(*save_ptr)); - - return cpu_ops[cpu]->cpu_suspend(arg); } /* @@ -56,15 +51,15 @@ void __init cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *)) } /** - * cpu_suspend + * cpu_suspend() - function to enter a low-power state + * @arg: argument to pass to CPU suspend operations * - * @arg: argument to pass to the finisher function + * Return: 0 on success, -EOPNOTSUPP if CPU suspend hook not initialized, CPU + * operations back-end error code otherwise. */ int cpu_suspend(unsigned long arg) { - struct mm_struct *mm = current->active_mm; - int ret, cpu = smp_processor_id(); - unsigned long flags; + int cpu = smp_processor_id(); /* * If cpu_ops have not been registered or suspend @@ -72,6 +67,21 @@ int cpu_suspend(unsigned long arg) */ if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_suspend) return -EOPNOTSUPP; + return cpu_ops[cpu]->cpu_suspend(arg); +} + +/* + * __cpu_suspend + * + * arg: argument to pass to the finisher function + * fn: finisher function pointer + * + */ +int __cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) +{ + struct mm_struct *mm = current->active_mm; + int ret; + unsigned long flags; /* * From this point debug exceptions are disabled to prevent @@ -86,7 +96,7 @@ int cpu_suspend(unsigned long arg) * page tables, so that the thread address space is properly * set-up on function return. */ - ret = __cpu_suspend(arg); + ret = __cpu_suspend_enter(arg, fn); if (ret == 0) { cpu_switch_mm(mm->pgd, mm); flush_tlb_all(); @@ -95,7 +105,7 @@ int cpu_suspend(unsigned long arg) * Restore per-cpu offset before any kernel * subsystem relying on it has a chance to run. */ - set_my_cpu_offset(per_cpu_offset(cpu)); + set_my_cpu_offset(per_cpu_offset(smp_processor_id())); /* * Restore HW breakpoint registers to sane values |