* [PATCH 1/2] drm/exynos/vidi: use timer for vblanks instead of sleeping worker
2016-09-23 8:15 ` [PATCH 0/2] Use drm-core helpers to wait for updates Andrzej Hajda
@ 2016-09-23 8:15 ` Andrzej Hajda
2016-09-23 12:27 ` Gustavo Padovan
2016-09-23 8:15 ` [PATCH 2/2] drm/exynos: fix pending update handling Andrzej Hajda
1 sibling, 1 reply; 5+ messages in thread
From: Andrzej Hajda @ 2016-09-23 8:15 UTC (permalink / raw)
To: Inki Dae
Cc: linux-samsung-soc, Bartlomiej Zolnierkiewicz, Daniel Vetter,
dri-devel, Tobias Jakobi, Marek Szyprowski
VIDI driver uses fake vblank handler to generate vblank events.
It was implemented using worker which slept for vblank time, additionally
it did not work if there were no page flips. The patch replaces it with
timer, uses drm_crtc_vblank_(on|off) helpers to manage it and fixes
behavior for non-page-flip cases.
This change allows further improvements of vblank in exynos-drm framework.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
drivers/gpu/drm/exynos/exynos_drm_vidi.c | 66 ++++++++++----------------------
1 file changed, 20 insertions(+), 46 deletions(-)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_vidi.c b/drivers/gpu/drm/exynos/exynos_drm_vidi.c
index e8f6c92..a91dad6 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_vidi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_vidi.c
@@ -15,6 +15,7 @@
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/component.h>
+#include <linux/timer.h>
#include <drm/exynos_drm.h>
@@ -28,6 +29,9 @@
#include "exynos_drm_plane.h"
#include "exynos_drm_vidi.h"
+/* VIDI uses fixed refresh rate of 50Hz */
+#define VIDI_REFRESH_TIME (1000 / 50)
+
/* vidi has totally three virtual windows. */
#define WINDOWS_NR 3
@@ -43,12 +47,9 @@ struct vidi_context {
struct exynos_drm_plane planes[WINDOWS_NR];
struct edid *raw_edid;
unsigned int clkdiv;
- unsigned long irq_flags;
unsigned int connected;
- bool vblank_on;
bool suspended;
- bool direct_vblank;
- struct work_struct work;
+ struct timer_list timer;
struct mutex lock;
int pipe;
};
@@ -102,30 +103,14 @@ static int vidi_enable_vblank(struct exynos_drm_crtc *crtc)
if (ctx->suspended)
return -EPERM;
- if (!test_and_set_bit(0, &ctx->irq_flags))
- ctx->vblank_on = true;
-
- ctx->direct_vblank = true;
-
- /*
- * in case of page flip request, vidi_finish_pageflip function
- * will not be called because direct_vblank is true and then
- * that function will be called by crtc_ops->update_plane callback
- */
- schedule_work(&ctx->work);
+ mod_timer(&ctx->timer,
+ jiffies + msecs_to_jiffies(VIDI_REFRESH_TIME) - 1);
return 0;
}
static void vidi_disable_vblank(struct exynos_drm_crtc *crtc)
{
- struct vidi_context *ctx = crtc->ctx;
-
- if (ctx->suspended)
- return;
-
- if (test_and_clear_bit(0, &ctx->irq_flags))
- ctx->vblank_on = false;
}
static void vidi_update_plane(struct exynos_drm_crtc *crtc,
@@ -140,9 +125,6 @@ static void vidi_update_plane(struct exynos_drm_crtc *crtc,
addr = exynos_drm_fb_dma_addr(state->fb, 0);
DRM_DEBUG_KMS("dma_addr = %pad\n", &addr);
-
- if (ctx->vblank_on)
- schedule_work(&ctx->work);
}
static void vidi_enable(struct exynos_drm_crtc *crtc)
@@ -153,17 +135,17 @@ static void vidi_enable(struct exynos_drm_crtc *crtc)
ctx->suspended = false;
- /* if vblank was enabled status, enable it again. */
- if (test_and_clear_bit(0, &ctx->irq_flags))
- vidi_enable_vblank(ctx->crtc);
-
mutex_unlock(&ctx->lock);
+
+ drm_crtc_vblank_on(&crtc->base);
}
static void vidi_disable(struct exynos_drm_crtc *crtc)
{
struct vidi_context *ctx = crtc->ctx;
+ drm_crtc_vblank_off(&crtc->base);
+
mutex_lock(&ctx->lock);
ctx->suspended = true;
@@ -190,28 +172,17 @@ static const struct exynos_drm_crtc_ops vidi_crtc_ops = {
.update_plane = vidi_update_plane,
};
-static void vidi_fake_vblank_handler(struct work_struct *work)
+static void vidi_fake_vblank_timer(unsigned long arg)
{
- struct vidi_context *ctx = container_of(work, struct vidi_context,
- work);
+ struct vidi_context *ctx = (void *)arg;
int win;
if (ctx->pipe < 0)
return;
- /* refresh rate is about 50Hz. */
- usleep_range(16000, 20000);
-
- mutex_lock(&ctx->lock);
-
- if (ctx->direct_vblank) {
- drm_crtc_handle_vblank(&ctx->crtc->base);
- ctx->direct_vblank = false;
- mutex_unlock(&ctx->lock);
- return;
- }
-
- mutex_unlock(&ctx->lock);
+ if (drm_crtc_handle_vblank(&ctx->crtc->base))
+ mod_timer(&ctx->timer,
+ jiffies + msecs_to_jiffies(VIDI_REFRESH_TIME) - 1);
for (win = 0 ; win < WINDOWS_NR ; win++) {
struct exynos_drm_plane *plane = &ctx->planes[win];
@@ -489,6 +460,9 @@ static int vidi_bind(struct device *dev, struct device *master, void *data)
static void vidi_unbind(struct device *dev, struct device *master, void *data)
{
+ struct vidi_context *ctx = dev_get_drvdata(dev);
+
+ del_timer_sync(&ctx->timer);
}
static const struct component_ops vidi_component_ops = {
@@ -507,7 +481,7 @@ static int vidi_probe(struct platform_device *pdev)
ctx->pdev = pdev;
- INIT_WORK(&ctx->work, vidi_fake_vblank_handler);
+ setup_timer(&ctx->timer, vidi_fake_vblank_timer, (unsigned long)ctx);
mutex_init(&ctx->lock);
--
2.7.4
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^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH 2/2] drm/exynos: fix pending update handling
2016-09-23 8:15 ` [PATCH 0/2] Use drm-core helpers to wait for updates Andrzej Hajda
2016-09-23 8:15 ` [PATCH 1/2] drm/exynos/vidi: use timer for vblanks instead of sleeping worker Andrzej Hajda
@ 2016-09-23 8:15 ` Andrzej Hajda
2016-09-23 12:28 ` Gustavo Padovan
1 sibling, 1 reply; 5+ messages in thread
From: Andrzej Hajda @ 2016-09-23 8:15 UTC (permalink / raw)
To: Inki Dae
Cc: linux-samsung-soc, Bartlomiej Zolnierkiewicz, Daniel Vetter,
dri-devel, Tobias Jakobi, Marek Szyprowski
Exynos DRM devices update their registers at vblank time. Exynos-DRM uses
custom mechanism to wait for vblank. This mechanism is error prone -
variables are not updated atomically. As a result in certain circumstances
user space can try to free buffers which are still in use by hardware,
in such cases IOMMU can throw OOPS.
The patch instead of fixing the mechanism replaces it with drm core helper.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
drivers/gpu/drm/exynos/exynos_drm_crtc.c | 16 +-----------
drivers/gpu/drm/exynos/exynos_drm_drv.c | 44 +-------------------------------
drivers/gpu/drm/exynos/exynos_drm_drv.h | 2 --
3 files changed, 2 insertions(+), 60 deletions(-)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_crtc.c b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
index 785ffa6..5b6845b 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_crtc.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
@@ -134,8 +134,6 @@ struct exynos_drm_crtc *exynos_drm_crtc_create(struct drm_device *drm_dev,
exynos_crtc->ops = ops;
exynos_crtc->ctx = ctx;
- init_waitqueue_head(&exynos_crtc->wait_update);
-
crtc = &exynos_crtc->base;
private->crtc[pipe] = crtc;
@@ -175,13 +173,6 @@ void exynos_drm_crtc_disable_vblank(struct drm_device *dev, unsigned int pipe)
exynos_crtc->ops->disable_vblank(exynos_crtc);
}
-void exynos_drm_crtc_wait_pending_update(struct exynos_drm_crtc *exynos_crtc)
-{
- wait_event_timeout(exynos_crtc->wait_update,
- (atomic_read(&exynos_crtc->pending_update) == 0),
- msecs_to_jiffies(50));
-}
-
void exynos_drm_crtc_finish_update(struct exynos_drm_crtc *exynos_crtc,
struct exynos_drm_plane *exynos_plane)
{
@@ -190,9 +181,6 @@ void exynos_drm_crtc_finish_update(struct exynos_drm_crtc *exynos_crtc,
exynos_plane->pending_fb = NULL;
- if (atomic_dec_and_test(&exynos_crtc->pending_update))
- wake_up(&exynos_crtc->wait_update);
-
spin_lock_irqsave(&crtc->dev->event_lock, flags);
if (exynos_crtc->event)
drm_crtc_send_vblank_event(crtc, exynos_crtc->event);
@@ -235,10 +223,8 @@ void exynos_drm_crtc_cancel_page_flip(struct drm_crtc *crtc,
spin_lock_irqsave(&crtc->dev->event_lock, flags);
e = exynos_crtc->event;
- if (e && e->base.file_priv == file) {
+ if (e && e->base.file_priv == file)
exynos_crtc->event = NULL;
- atomic_dec(&exynos_crtc->pending_update);
- }
spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c
index 877d2efa..a1bc13f 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_drv.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c
@@ -45,37 +45,11 @@ struct exynos_atomic_commit {
u32 crtcs;
};
-static void exynos_atomic_wait_for_commit(struct drm_atomic_state *state)
-{
- struct drm_crtc_state *crtc_state;
- struct drm_crtc *crtc;
- int i, ret;
-
- for_each_crtc_in_state(state, crtc, crtc_state, i) {
- struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
-
- if (!crtc->state->enable)
- continue;
-
- ret = drm_crtc_vblank_get(crtc);
- if (ret)
- continue;
-
- exynos_drm_crtc_wait_pending_update(exynos_crtc);
- drm_crtc_vblank_put(crtc);
- }
-}
-
static void exynos_atomic_commit_complete(struct exynos_atomic_commit *commit)
{
struct drm_device *dev = commit->dev;
struct exynos_drm_private *priv = dev->dev_private;
struct drm_atomic_state *state = commit->state;
- struct drm_plane *plane;
- struct drm_crtc *crtc;
- struct drm_plane_state *plane_state;
- struct drm_crtc_state *crtc_state;
- int i;
drm_atomic_helper_commit_modeset_disables(dev, state);
@@ -89,25 +63,9 @@ static void exynos_atomic_commit_complete(struct exynos_atomic_commit *commit)
* have the relevant clocks enabled to perform the update.
*/
- for_each_crtc_in_state(state, crtc, crtc_state, i) {
- struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
-
- atomic_set(&exynos_crtc->pending_update, 0);
- }
-
- for_each_plane_in_state(state, plane, plane_state, i) {
- struct exynos_drm_crtc *exynos_crtc =
- to_exynos_crtc(plane->crtc);
-
- if (!plane->crtc)
- continue;
-
- atomic_inc(&exynos_crtc->pending_update);
- }
-
drm_atomic_helper_commit_planes(dev, state, false);
- exynos_atomic_wait_for_commit(state);
+ drm_atomic_helper_wait_for_vblanks(dev, state);
drm_atomic_helper_cleanup_planes(dev, state);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.h b/drivers/gpu/drm/exynos/exynos_drm_drv.h
index 7f1a49d..cee3a4c 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_drv.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_drv.h
@@ -173,8 +173,6 @@ struct exynos_drm_crtc {
enum exynos_drm_output_type type;
unsigned int pipe;
struct drm_pending_vblank_event *event;
- wait_queue_head_t wait_update;
- atomic_t pending_update;
const struct exynos_drm_crtc_ops *ops;
void *ctx;
struct exynos_drm_clk *pipe_clk;
--
2.7.4
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^ permalink raw reply related [flat|nested] 5+ messages in thread