diff options
Diffstat (limited to 'arch/arm64/kernel/suspend.c')
| -rw-r--r-- | arch/arm64/kernel/suspend.c | 82 |
1 files changed, 33 insertions, 49 deletions
diff --git a/arch/arm64/kernel/suspend.c b/arch/arm64/kernel/suspend.c index e7a96462ca2d..468b939f3471 100644 --- a/arch/arm64/kernel/suspend.c +++ b/arch/arm64/kernel/suspend.c @@ -13,30 +13,11 @@ #include <asm/suspend.h> #include <asm/tlbflush.h> -extern int __cpu_suspend_enter(unsigned long arg, int (*fn)(unsigned long)); /* - * 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. - * - * ptr: CPU context virtual address - * save_ptr: address of the location where the context physical address - * must be saved + * This is allocated by cpu_suspend_init(), and used to store a pointer to + * the 'struct sleep_stack_data' the contains a particular CPUs state. */ -void notrace __cpu_suspend_save(struct cpu_suspend_ctx *ptr, - phys_addr_t *save_ptr) -{ - *save_ptr = virt_to_phys(ptr); - - cpu_do_suspend(ptr); - /* - * Only flush the context that must be retrieved with the MMU - * off. VA primitives ensure the flush is applied to all - * cache levels so context is pushed to DRAM. - */ - __flush_dcache_area(ptr, sizeof(*ptr)); - __flush_dcache_area(save_ptr, sizeof(*save_ptr)); -} +unsigned long *sleep_save_stash; /* * This hook is provided so that cpu_suspend code can restore HW @@ -54,6 +35,24 @@ void __init cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *)) hw_breakpoint_restore = hw_bp_restore; } +void notrace __cpu_suspend_exit(void) +{ + /* + * We are resuming from reset with the idmap active in TTBR0_EL1. + * We must uninstall the idmap and restore the expected MMU + * state before we can possibly return to userspace. + */ + cpu_uninstall_idmap(); + + /* + * Restore HW breakpoint registers to sane values + * before debug exceptions are possibly reenabled + * through local_dbg_restore. + */ + if (hw_breakpoint_restore) + hw_breakpoint_restore(NULL); +} + /* * cpu_suspend * @@ -63,8 +62,9 @@ void __init cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *)) */ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) { - int ret; + int ret = 0; unsigned long flags; + struct sleep_stack_data state; /* * From this point debug exceptions are disabled to prevent @@ -80,20 +80,9 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) */ pause_graph_tracing(); - /* - * mm context saved on the stack, it will be restored when - * the cpu comes out of reset through the identity mapped - * page tables, so that the thread address space is properly - * set-up on function return. - */ - ret = __cpu_suspend_enter(arg, fn); - if (ret == 0) { - /* - * We are resuming from reset with the idmap active in TTBR0_EL1. - * We must uninstall the idmap and restore the expected MMU - * state before we can possibly return to userspace. - */ - cpu_uninstall_idmap(); + if (__cpu_suspend_enter(&state)) { + /* Call the suspend finisher */ + ret = fn(arg); /* * PSTATE was not saved over suspend/resume, re-enable any @@ -108,8 +97,10 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) * before debug exceptions are possibly reenabled * through local_dbg_restore. */ - if (hw_breakpoint_restore) - hw_breakpoint_restore(NULL); + if (!ret) + ret = -EOPNOTSUPP; + } else { + __cpu_suspend_exit(); } unpause_graph_tracing(); @@ -124,22 +115,15 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) return ret; } -struct sleep_save_sp sleep_save_sp; - static int __init cpu_suspend_init(void) { - void *ctx_ptr; - /* ctx_ptr is an array of physical addresses */ - ctx_ptr = kcalloc(mpidr_hash_size(), sizeof(phys_addr_t), GFP_KERNEL); + sleep_save_stash = kcalloc(mpidr_hash_size(), sizeof(*sleep_save_stash), + GFP_KERNEL); - if (WARN_ON(!ctx_ptr)) + if (WARN_ON(!sleep_save_stash)) return -ENOMEM; - sleep_save_sp.save_ptr_stash = ctx_ptr; - sleep_save_sp.save_ptr_stash_phys = virt_to_phys(ctx_ptr); - __flush_dcache_area(&sleep_save_sp, sizeof(struct sleep_save_sp)); - return 0; } early_initcall(cpu_suspend_init); |