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Diffstat (limited to 'arch/i386/kernel/acpi/sleep.c')
-rw-r--r--arch/i386/kernel/acpi/sleep.c93
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 000000000000..28bb0514bb6e
--- /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);