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path: root/drivers/gpu/drm/drm_self_refresh_helper.c
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Diffstat (limited to 'drivers/gpu/drm/drm_self_refresh_helper.c')
-rw-r--r--drivers/gpu/drm/drm_self_refresh_helper.c73
1 files changed, 66 insertions, 7 deletions
diff --git a/drivers/gpu/drm/drm_self_refresh_helper.c b/drivers/gpu/drm/drm_self_refresh_helper.c
index 4b9424a8f1f1..68f4765a5896 100644
--- a/drivers/gpu/drm/drm_self_refresh_helper.c
+++ b/drivers/gpu/drm/drm_self_refresh_helper.c
@@ -5,6 +5,7 @@
* Authors:
* Sean Paul <seanpaul@chromium.org>
*/
+#include <linux/average.h>
#include <linux/bitops.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
@@ -50,11 +51,17 @@
* atomic_check when &drm_crtc_state.self_refresh_active is true.
*/
+#define SELF_REFRESH_AVG_SEED_MS 200
+
+DECLARE_EWMA(psr_time, 4, 4)
+
struct drm_self_refresh_data {
struct drm_crtc *crtc;
struct delayed_work entry_work;
- struct drm_atomic_state *save_state;
- unsigned int entry_delay_ms;
+
+ struct mutex avg_mutex;
+ struct ewma_psr_time entry_avg_ms;
+ struct ewma_psr_time exit_avg_ms;
};
static void drm_self_refresh_helper_entry_work(struct work_struct *work)
@@ -123,6 +130,44 @@ out_drop_locks:
}
/**
+ * drm_self_refresh_helper_update_avg_times - Updates a crtc's SR time averages
+ * @state: the state which has just been applied to hardware
+ * @commit_time_ms: the amount of time in ms that this commit took to complete
+ *
+ * Called after &drm_mode_config_funcs.atomic_commit_tail, this function will
+ * update the average entry/exit self refresh times on self refresh transitions.
+ * These averages will be used when calculating how long to delay before
+ * entering self refresh mode after activity.
+ */
+void drm_self_refresh_helper_update_avg_times(struct drm_atomic_state *state,
+ unsigned int commit_time_ms)
+{
+ struct drm_crtc *crtc;
+ struct drm_crtc_state *old_crtc_state, *new_crtc_state;
+ int i;
+
+ for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state,
+ new_crtc_state, i) {
+ struct drm_self_refresh_data *sr_data = crtc->self_refresh_data;
+ struct ewma_psr_time *time;
+
+ if (old_crtc_state->self_refresh_active ==
+ new_crtc_state->self_refresh_active)
+ continue;
+
+ if (new_crtc_state->self_refresh_active)
+ time = &sr_data->entry_avg_ms;
+ else
+ time = &sr_data->exit_avg_ms;
+
+ mutex_lock(&sr_data->avg_mutex);
+ ewma_psr_time_add(time, commit_time_ms);
+ mutex_unlock(&sr_data->avg_mutex);
+ }
+}
+EXPORT_SYMBOL(drm_self_refresh_helper_update_avg_times);
+
+/**
* drm_self_refresh_helper_alter_state - Alters the atomic state for SR exit
* @state: the state currently being checked
*
@@ -153,6 +198,7 @@ void drm_self_refresh_helper_alter_state(struct drm_atomic_state *state)
for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
struct drm_self_refresh_data *sr_data;
+ unsigned int delay;
/* Don't trigger the entry timer when we're already in SR */
if (crtc_state->self_refresh_active)
@@ -162,8 +208,13 @@ void drm_self_refresh_helper_alter_state(struct drm_atomic_state *state)
if (!sr_data)
continue;
+ mutex_lock(&sr_data->avg_mutex);
+ delay = (ewma_psr_time_read(&sr_data->entry_avg_ms) +
+ ewma_psr_time_read(&sr_data->exit_avg_ms)) * 2;
+ mutex_unlock(&sr_data->avg_mutex);
+
mod_delayed_work(system_wq, &sr_data->entry_work,
- msecs_to_jiffies(sr_data->entry_delay_ms));
+ msecs_to_jiffies(delay));
}
}
EXPORT_SYMBOL(drm_self_refresh_helper_alter_state);
@@ -171,12 +222,10 @@ EXPORT_SYMBOL(drm_self_refresh_helper_alter_state);
/**
* drm_self_refresh_helper_init - Initializes self refresh helpers for a crtc
* @crtc: the crtc which supports self refresh supported displays
- * @entry_delay_ms: amount of inactivity to wait before entering self refresh
*
* Returns zero if successful or -errno on failure
*/
-int drm_self_refresh_helper_init(struct drm_crtc *crtc,
- unsigned int entry_delay_ms)
+int drm_self_refresh_helper_init(struct drm_crtc *crtc)
{
struct drm_self_refresh_data *sr_data = crtc->self_refresh_data;
@@ -190,8 +239,18 @@ int drm_self_refresh_helper_init(struct drm_crtc *crtc,
INIT_DELAYED_WORK(&sr_data->entry_work,
drm_self_refresh_helper_entry_work);
- sr_data->entry_delay_ms = entry_delay_ms;
sr_data->crtc = crtc;
+ mutex_init(&sr_data->avg_mutex);
+ ewma_psr_time_init(&sr_data->entry_avg_ms);
+ ewma_psr_time_init(&sr_data->exit_avg_ms);
+
+ /*
+ * Seed the averages so they're non-zero (and sufficiently large
+ * for even poorly performing panels). As time goes on, this will be
+ * averaged out and the values will trend to their true value.
+ */
+ ewma_psr_time_add(&sr_data->entry_avg_ms, SELF_REFRESH_AVG_SEED_MS);
+ ewma_psr_time_add(&sr_data->exit_avg_ms, SELF_REFRESH_AVG_SEED_MS);
crtc->self_refresh_data = sr_data;
return 0;