linux/arch/arm64/include/asm/suspend.h
James Morse adc9b2dfd0 arm64: kernel: Rework finisher callback out of __cpu_suspend_enter()
Hibernate could make use of the cpu_suspend() code to save/restore cpu
state, however it needs to be able to return '0' from the 'finisher'.

Rework cpu_suspend() so that the finisher is called from C code,
independently from the save/restore of cpu state. Space to save the context
in is allocated in the caller's stack frame, and passed into
__cpu_suspend_enter().

Hibernate's use of this API will look like a copy of the cpu_suspend()
function.

Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-28 12:05:46 +01:00

47 lines
1.4 KiB
C

#ifndef __ASM_SUSPEND_H
#define __ASM_SUSPEND_H
#define NR_CTX_REGS 11
#define NR_CALLEE_SAVED_REGS 12
/*
* struct cpu_suspend_ctx must be 16-byte aligned since it is allocated on
* the stack, which must be 16-byte aligned on v8
*/
struct cpu_suspend_ctx {
/*
* This struct must be kept in sync with
* cpu_do_{suspend/resume} in mm/proc.S
*/
u64 ctx_regs[NR_CTX_REGS];
u64 sp;
} __aligned(16);
struct sleep_save_sp {
phys_addr_t *save_ptr_stash;
phys_addr_t save_ptr_stash_phys;
};
/*
* Memory to save the cpu state is allocated on the stack by
* __cpu_suspend_enter()'s caller, and populated by __cpu_suspend_enter().
* This data must survive until cpu_resume() is called.
*
* This struct desribes the size and the layout of the saved cpu state.
* The layout of the callee_saved_regs is defined by the implementation
* of __cpu_suspend_enter(), and cpu_resume(). This struct must be passed
* in by the caller as __cpu_suspend_enter()'s stack-frame is gone once it
* returns, and the data would be subsequently corrupted by the call to the
* finisher.
*/
struct sleep_stack_data {
struct cpu_suspend_ctx system_regs;
unsigned long callee_saved_regs[NR_CALLEE_SAVED_REGS];
};
extern int cpu_suspend(unsigned long arg, int (*fn)(unsigned long));
extern void cpu_resume(void);
int __cpu_suspend_enter(struct sleep_stack_data *state);
void __cpu_suspend_exit(void);
#endif