Re: [PATCH v3 2/3] drm/msm/dpu: split dpu_encoder_wait_for_event into two functions

From: Abhinav Kumar
Date: Sun Feb 25 2024 - 14:49:53 EST



On 2/25/2024 6:12 AM, Dmitry Baryshkov wrote:
Stop multiplexing several events via the dpu_encoder_wait_for_event()
function. Split it into two distinct functions two allow separate
handling of those events.


I understand the idea but would handling of those events be really distinct?

Like if wait_for_commit_done timedout or wait_for_tx_complete timedout, the handling will be similar from my PoV.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 74 +++++++++++++++++++++--------
drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h | 22 ++-------
drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 2 +-
drivers/gpu/drm/msm/msm_drv.h | 10 ----
4 files changed, 59 insertions(+), 49 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 194dbb08331d..30f349c8a1e5 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -1282,7 +1282,7 @@ static void dpu_encoder_virt_atomic_disable(struct drm_encoder *drm_enc,
trace_dpu_enc_disable(DRMID(drm_enc));
/* wait for idle */
- dpu_encoder_wait_for_event(drm_enc, MSM_ENC_TX_COMPLETE);
+ dpu_encoder_wait_for_tx_complete(drm_enc);
dpu_encoder_resource_control(drm_enc, DPU_ENC_RC_EVENT_PRE_STOP);
@@ -2402,10 +2402,23 @@ struct drm_encoder *dpu_encoder_init(struct drm_device *dev,
return &dpu_enc->base;
}
-int dpu_encoder_wait_for_event(struct drm_encoder *drm_enc,
- enum msm_event_wait event)
+/**
+ * dpu_encoder_wait_for_commit_done() - Wait for encoder to flush pending state
+ * @drm_enc: encoder pointer
+ *
+ * Wait for hardware to have flushed the current pending frames to hardware at
+ * a vblank or ctl_start Encoders will map this differently depending on the
+ * panel type.
+ *

Missing a '.' between ctl_start and Encoder?

+ * MSM_ENC_TX_COMPLETE - Wait for the hardware to transfer all the pixels to
+ * the panel. Encoders will map this differently
+ * depending on the panel type.
+ * vid mode -> vsync_irq
+ * cmd mode -> pp_done
+ * Return: 0 on success, -EWOULDBLOCK if already signaled, error otherwise
+ */
+int dpu_encoder_wait_for_commit_done(struct drm_encoder *drm_enc)
{
- int (*fn_wait)(struct dpu_encoder_phys *phys_enc) = NULL;
struct dpu_encoder_virt *dpu_enc = NULL;
int i, ret = 0;
@@ -2419,23 +2432,46 @@ int dpu_encoder_wait_for_event(struct drm_encoder *drm_enc,
for (i = 0; i < dpu_enc->num_phys_encs; i++) {
struct dpu_encoder_phys *phys = dpu_enc->phys_encs[i];
- switch (event) {
- case MSM_ENC_COMMIT_DONE:
- fn_wait = phys->ops.wait_for_commit_done;
- break;
- case MSM_ENC_TX_COMPLETE:
- fn_wait = phys->ops.wait_for_tx_complete;
- break;
- default:
- DPU_ERROR_ENC(dpu_enc, "unknown wait event %d\n",
- event);
- return -EINVAL;
+ if (phys->ops.wait_for_commit_done) {
+ DPU_ATRACE_BEGIN("wait_for_commit_done");
+ ret = phys->ops.wait_for_commit_done(phys);
+ DPU_ATRACE_END("wait_for_commit_done");
+ if (ret)
+ return ret;
}
+ }
+
+ return ret;
+}
+
+/**
+ * dpu_encoder_wait_for_tx_complete() - Wait for encoder to transfer pixels to panel
+ * @drm_enc: encoder pointer
+ *
+ * Wait for the hardware to transfer all the pixels to the panel. Encoders will
+ * map this differently depending on the panel type.
+ *
+ * Return: 0 on success, -EWOULDBLOCK if already signaled, error otherwise
+ */
+int dpu_encoder_wait_for_tx_complete(struct drm_encoder *drm_enc)
+{
+ struct dpu_encoder_virt *dpu_enc = NULL;
+ int i, ret = 0;
+
+ if (!drm_enc) {
+ DPU_ERROR("invalid encoder\n");
+ return -EINVAL;
+ }
+ dpu_enc = to_dpu_encoder_virt(drm_enc);
+ DPU_DEBUG_ENC(dpu_enc, "\n");
+
+ for (i = 0; i < dpu_enc->num_phys_encs; i++) {
+ struct dpu_encoder_phys *phys = dpu_enc->phys_encs[i];
- if (fn_wait) {
- DPU_ATRACE_BEGIN("wait_for_completion_event");
- ret = fn_wait(phys);
- DPU_ATRACE_END("wait_for_completion_event");
+ if (phys->ops.wait_for_tx_complete) {
+ DPU_ATRACE_BEGIN("wait_for_tx_complete");
+ ret = phys->ops.wait_for_tx_complete(phys);
+ DPU_ATRACE_END("wait_for_tx_complete");
if (ret)
return ret;
}
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
index fe6b1d312a74..0c928d1876e4 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
@@ -93,25 +93,9 @@ void dpu_encoder_kickoff(struct drm_encoder *encoder);
*/
int dpu_encoder_vsync_time(struct drm_encoder *drm_enc, ktime_t *wakeup_time);
-/**
- * dpu_encoder_wait_for_event - Waits for encoder events
- * @encoder: encoder pointer
- * @event: event to wait for
- * MSM_ENC_COMMIT_DONE - Wait for hardware to have flushed the current pending
- * frames to hardware at a vblank or ctl_start
- * Encoders will map this differently depending on the
- * panel type.
- * vid mode -> vsync_irq
- * cmd mode -> ctl_start
- * MSM_ENC_TX_COMPLETE - Wait for the hardware to transfer all the pixels to
- * the panel. Encoders will map this differently
- * depending on the panel type.
- * vid mode -> vsync_irq
- * cmd mode -> pp_done
- * Returns: 0 on success, -EWOULDBLOCK if already signaled, error otherwise
- */
-int dpu_encoder_wait_for_event(struct drm_encoder *drm_encoder,
- enum msm_event_wait event);
+int dpu_encoder_wait_for_commit_done(struct drm_encoder *drm_encoder);
+
+int dpu_encoder_wait_for_tx_complete(struct drm_encoder *drm_encoder);
/*
* dpu_encoder_get_intf_mode - get interface mode of the given encoder
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index d6412395bacc..26b5e54031d9 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -476,7 +476,7 @@ static void dpu_kms_wait_for_commit_done(struct msm_kms *kms,
* mode panels. This may be a no-op for command mode panels.
*/
trace_dpu_kms_wait_for_commit_done(DRMID(crtc));
- ret = dpu_encoder_wait_for_event(encoder, MSM_ENC_COMMIT_DONE);
+ ret = dpu_encoder_wait_for_commit_done(encoder);
if (ret && ret != -EWOULDBLOCK) {
DPU_ERROR("wait for commit done returned %d\n", ret);
break;
diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index 762e13e2df74..91cf57f72321 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -74,16 +74,6 @@ enum msm_dsi_controller {
#define MSM_GPU_MAX_RINGS 4
#define MAX_H_TILES_PER_DISPLAY 2
-/**
- * enum msm_event_wait - type of HW events to wait for
- * @MSM_ENC_COMMIT_DONE - wait for the driver to flush the registers to HW
- * @MSM_ENC_TX_COMPLETE - wait for the HW to transfer the frame to panel
- */
-enum msm_event_wait {
- MSM_ENC_COMMIT_DONE = 0,
- MSM_ENC_TX_COMPLETE,
-};
-
/**
* struct msm_display_topology - defines a display topology pipeline
* @num_lm: number of layer mixers used