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-rw-r--r--drivers/acpi/sleep/main.c53
-rw-r--r--include/linux/suspend.h13
-rw-r--r--kernel/power/swsusp.c122
3 files changed, 180 insertions, 8 deletions
diff --git a/drivers/acpi/sleep/main.c b/drivers/acpi/sleep/main.c
index 28a691cc..45a8015 100644
--- a/drivers/acpi/sleep/main.c
+++ b/drivers/acpi/sleep/main.c
@@ -394,9 +394,25 @@ void __init acpi_no_s4_hw_signature(void)
static int acpi_hibernation_begin(void)
{
- acpi_target_sleep_state = ACPI_STATE_S4;
- acpi_sleep_tts_switch(acpi_target_sleep_state);
- return 0;
+ int error;
+
+ error = hibernate_nvs_alloc();
+ if (!error) {
+ acpi_target_sleep_state = ACPI_STATE_S4;
+ acpi_sleep_tts_switch(acpi_target_sleep_state);
+ }
+
+ return error;
+}
+
+static int acpi_hibernation_pre_snapshot(void)
+{
+ int error = acpi_pm_prepare();
+
+ if (!error)
+ hibernate_nvs_save();
+
+ return error;
}
static int acpi_hibernation_enter(void)
@@ -417,6 +433,12 @@ static int acpi_hibernation_enter(void)
return ACPI_SUCCESS(status) ? 0 : -EFAULT;
}
+static void acpi_hibernation_finish(void)
+{
+ hibernate_nvs_free();
+ acpi_pm_finish();
+}
+
static void acpi_hibernation_leave(void)
{
/*
@@ -432,6 +454,8 @@ static void acpi_hibernation_leave(void)
"cannot resume!\n");
panic("ACPI S4 hardware signature mismatch");
}
+ /* Restore the NVS memory area */
+ hibernate_nvs_restore();
}
static void acpi_pm_enable_gpes(void)
@@ -442,8 +466,8 @@ static void acpi_pm_enable_gpes(void)
static struct platform_hibernation_ops acpi_hibernation_ops = {
.begin = acpi_hibernation_begin,
.end = acpi_pm_end,
- .pre_snapshot = acpi_pm_prepare,
- .finish = acpi_pm_finish,
+ .pre_snapshot = acpi_hibernation_pre_snapshot,
+ .finish = acpi_hibernation_finish,
.prepare = acpi_pm_prepare,
.enter = acpi_hibernation_enter,
.leave = acpi_hibernation_leave,
@@ -469,8 +493,21 @@ static int acpi_hibernation_begin_old(void)
error = acpi_sleep_prepare(ACPI_STATE_S4);
+ if (!error) {
+ error = hibernate_nvs_alloc();
+ if (!error)
+ acpi_target_sleep_state = ACPI_STATE_S4;
+ }
+ return error;
+}
+
+static int acpi_hibernation_pre_snapshot_old(void)
+{
+ int error = acpi_pm_disable_gpes();
+
if (!error)
- acpi_target_sleep_state = ACPI_STATE_S4;
+ hibernate_nvs_save();
+
return error;
}
@@ -481,8 +518,8 @@ static int acpi_hibernation_begin_old(void)
static struct platform_hibernation_ops acpi_hibernation_ops_old = {
.begin = acpi_hibernation_begin_old,
.end = acpi_pm_end,
- .pre_snapshot = acpi_pm_disable_gpes,
- .finish = acpi_pm_finish,
+ .pre_snapshot = acpi_hibernation_pre_snapshot_old,
+ .finish = acpi_hibernation_finish,
.prepare = acpi_pm_disable_gpes,
.enter = acpi_hibernation_enter,
.leave = acpi_hibernation_leave,
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 2ce8207..2b409c4 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -232,6 +232,11 @@ extern unsigned long get_safe_page(gfp_t gfp_mask);
extern void hibernation_set_ops(struct platform_hibernation_ops *ops);
extern int hibernate(void);
+extern int hibernate_nvs_register(unsigned long start, unsigned long size);
+extern int hibernate_nvs_alloc(void);
+extern void hibernate_nvs_free(void);
+extern void hibernate_nvs_save(void);
+extern void hibernate_nvs_restore(void);
#else /* CONFIG_HIBERNATION */
static inline int swsusp_page_is_forbidden(struct page *p) { return 0; }
static inline void swsusp_set_page_free(struct page *p) {}
@@ -239,6 +244,14 @@ static inline void swsusp_unset_page_free(struct page *p) {}
static inline void hibernation_set_ops(struct platform_hibernation_ops *ops) {}
static inline int hibernate(void) { return -ENOSYS; }
+static inline int hibernate_nvs_register(unsigned long a, unsigned long b)
+{
+ return 0;
+}
+static inline int hibernate_nvs_alloc(void) { return 0; }
+static inline void hibernate_nvs_free(void) {}
+static inline void hibernate_nvs_save(void) {}
+static inline void hibernate_nvs_restore(void) {}
#endif /* CONFIG_HIBERNATION */
#ifdef CONFIG_PM_SLEEP
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
index 023ff2a..a92c914 100644
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -262,3 +262,125 @@ int swsusp_shrink_memory(void)
return 0;
}
+
+/*
+ * Platforms, like ACPI, may want us to save some memory used by them during
+ * hibernation and to restore the contents of this memory during the subsequent
+ * resume. The code below implements a mechanism allowing us to do that.
+ */
+
+struct nvs_page {
+ unsigned long phys_start;
+ unsigned int size;
+ void *kaddr;
+ void *data;
+ struct list_head node;
+};
+
+static LIST_HEAD(nvs_list);
+
+/**
+ * hibernate_nvs_register - register platform NVS memory region to save
+ * @start - physical address of the region
+ * @size - size of the region
+ *
+ * The NVS region need not be page-aligned (both ends) and we arrange
+ * things so that the data from page-aligned addresses in this region will
+ * be copied into separate RAM pages.
+ */
+int hibernate_nvs_register(unsigned long start, unsigned long size)
+{
+ struct nvs_page *entry, *next;
+
+ while (size > 0) {
+ unsigned int nr_bytes;
+
+ entry = kzalloc(sizeof(struct nvs_page), GFP_KERNEL);
+ if (!entry)
+ goto Error;
+
+ list_add_tail(&entry->node, &nvs_list);
+ entry->phys_start = start;
+ nr_bytes = PAGE_SIZE - (start & ~PAGE_MASK);
+ entry->size = (size < nr_bytes) ? size : nr_bytes;
+
+ start += entry->size;
+ size -= entry->size;
+ }
+ return 0;
+
+ Error:
+ list_for_each_entry_safe(entry, next, &nvs_list, node) {
+ list_del(&entry->node);
+ kfree(entry);
+ }
+ return -ENOMEM;
+}
+
+/**
+ * hibernate_nvs_free - free data pages allocated for saving NVS regions
+ */
+void hibernate_nvs_free(void)
+{
+ struct nvs_page *entry;
+
+ list_for_each_entry(entry, &nvs_list, node)
+ if (entry->data) {
+ free_page((unsigned long)entry->data);
+ entry->data = NULL;
+ if (entry->kaddr) {
+ iounmap(entry->kaddr);
+ entry->kaddr = NULL;
+ }
+ }
+}
+
+/**
+ * hibernate_nvs_alloc - allocate memory necessary for saving NVS regions
+ */
+int hibernate_nvs_alloc(void)
+{
+ struct nvs_page *entry;
+
+ list_for_each_entry(entry, &nvs_list, node) {
+ entry->data = (void *)__get_free_page(GFP_KERNEL);
+ if (!entry->data) {
+ hibernate_nvs_free();
+ return -ENOMEM;
+ }
+ }
+ return 0;
+}
+
+/**
+ * hibernate_nvs_save - save NVS memory regions
+ */
+void hibernate_nvs_save(void)
+{
+ struct nvs_page *entry;
+
+ printk(KERN_INFO "PM: Saving platform NVS memory\n");
+
+ list_for_each_entry(entry, &nvs_list, node)
+ if (entry->data) {
+ entry->kaddr = ioremap(entry->phys_start, entry->size);
+ memcpy(entry->data, entry->kaddr, entry->size);
+ }
+}
+
+/**
+ * hibernate_nvs_restore - restore NVS memory regions
+ *
+ * This function is going to be called with interrupts disabled, so it
+ * cannot iounmap the virtual addresses used to access the NVS region.
+ */
+void hibernate_nvs_restore(void)
+{
+ struct nvs_page *entry;
+
+ printk(KERN_INFO "PM: Restoring platform NVS memory\n");
+
+ list_for_each_entry(entry, &nvs_list, node)
+ if (entry->data)
+ memcpy(entry->kaddr, entry->data, entry->size);
+}
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