diff options
Diffstat (limited to 'arch/i386/kernel/acpi/sleep.c')
-rw-r--r-- | arch/i386/kernel/acpi/sleep.c | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/arch/i386/kernel/acpi/sleep.c b/arch/i386/kernel/acpi/sleep.c new file mode 100644 index 00000000000..28bb0514bb6 --- /dev/null +++ b/arch/i386/kernel/acpi/sleep.c @@ -0,0 +1,93 @@ +/* + * sleep.c - x86-specific ACPI sleep support. + * + * Copyright (C) 2001-2003 Patrick Mochel + * Copyright (C) 2001-2003 Pavel Machek <pavel@suse.cz> + */ + +#include <linux/acpi.h> +#include <linux/bootmem.h> +#include <asm/smp.h> +#include <asm/tlbflush.h> + +/* address in low memory of the wakeup routine. */ +unsigned long acpi_wakeup_address = 0; +unsigned long acpi_video_flags; +extern char wakeup_start, wakeup_end; + +extern void zap_low_mappings(void); + +extern unsigned long FASTCALL(acpi_copy_wakeup_routine(unsigned long)); + +static void init_low_mapping(pgd_t *pgd, int pgd_limit) +{ + int pgd_ofs = 0; + + while ((pgd_ofs < pgd_limit) && (pgd_ofs + USER_PTRS_PER_PGD < PTRS_PER_PGD)) { + set_pgd(pgd, *(pgd+USER_PTRS_PER_PGD)); + pgd_ofs++, pgd++; + } + flush_tlb_all(); +} + +/** + * acpi_save_state_mem - save kernel state + * + * Create an identity mapped page table and copy the wakeup routine to + * low memory. + */ +int acpi_save_state_mem (void) +{ + if (!acpi_wakeup_address) + return 1; + init_low_mapping(swapper_pg_dir, USER_PTRS_PER_PGD); + memcpy((void *) acpi_wakeup_address, &wakeup_start, &wakeup_end - &wakeup_start); + acpi_copy_wakeup_routine(acpi_wakeup_address); + + return 0; +} + +/* + * acpi_restore_state - undo effects of acpi_save_state_mem + */ +void acpi_restore_state_mem (void) +{ + zap_low_mappings(); +} + +/** + * acpi_reserve_bootmem - do _very_ early ACPI initialisation + * + * We allocate a page from the first 1MB of memory for the wakeup + * routine for when we come back from a sleep state. The + * runtime allocator allows specification of <16MB pages, but not + * <1MB pages. + */ +void __init acpi_reserve_bootmem(void) +{ + if ((&wakeup_end - &wakeup_start) > PAGE_SIZE) { + printk(KERN_ERR "ACPI: Wakeup code way too big, S3 disabled.\n"); + return; + } + + acpi_wakeup_address = (unsigned long)alloc_bootmem_low(PAGE_SIZE); + if (!acpi_wakeup_address) + printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n"); +} + +static int __init acpi_sleep_setup(char *str) +{ + while ((str != NULL) && (*str != '\0')) { + if (strncmp(str, "s3_bios", 7) == 0) + acpi_video_flags = 1; + if (strncmp(str, "s3_mode", 7) == 0) + acpi_video_flags |= 2; + str = strchr(str, ','); + if (str != NULL) + str += strspn(str, ", \t"); + } + return 1; +} + + +__setup("acpi_sleep=", acpi_sleep_setup); |