On 05/02/2022 00:17, Abhinav Kumar wrote:
kms_writeback test cases also verify with a null fb for the
writeback connector job. In addition there are also other
commit paths which can result in kickoffs without a valid
framebuffer like while closing the fb which results in the
callback to drm_atomic_helper_dirtyfb() which internally
triggers a commit.
Add protection in the dpu driver to ensure that commits for
writeback encoders without a valid fb are gracefully skipped.
Signed-off-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
---
drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 9 +++++++++
drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 21 +++++++++++++++++++++
drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h | 6 ++++++
drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h | 1 +
drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c | 12 ++++++++++++
5 files changed, 49 insertions(+)
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
index e7c9fe1..f7963b0 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
@@ -869,6 +869,13 @@ void dpu_crtc_commit_kickoff(struct drm_crtc *crtc)
DPU_ATRACE_BEGIN("crtc_commit");
+ drm_for_each_encoder_mask(encoder, crtc->dev,
+ crtc->state->encoder_mask) {
+ if (!dpu_encoder_has_valid_fb(encoder)) {
Two small comments here. First, let's probably rename the function to
dpu_encoder_is_valid() or dpu_encoder_is_valid_for_commit() (ugh, too
long). There might be other cases (in theory), why encoder is invalid at
this moment.
Also (a minor nit): I think that we should commit if at least one of
encoders is valid. So we might want to create an encoder_valid_mask
basing on the calls to dpu_encoder. And then use it later for calling
dpu_encoder_prepare_for_kickoff() and dpu_encoder_kickoff().
+ DRM_DEBUG_ATOMIC("invalid FB not kicking off crtc\n");
+ goto end;
+ }
+ }
/*
* Encoder will flush/start now, unless it has a tx pending. If so, it
* may delay and flush at an irq event (e.g. ppdone)
@@ -891,6 +898,8 @@ void dpu_crtc_commit_kickoff(struct drm_crtc *crtc)
dpu_encoder_kickoff(encoder);
reinit_completion(&dpu_crtc->frame_done_comp);
+
+end:
DPU_ATRACE_END("crtc_commit");
}
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 3746432..e990dbc 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -1832,6 +1832,27 @@ void dpu_encoder_prepare_for_kickoff(struct drm_encoder *drm_enc)
}
}
+bool dpu_encoder_has_valid_fb(struct drm_encoder *drm_enc)
+{
+ struct dpu_encoder_virt *dpu_enc;
+ unsigned int i;
+ struct dpu_encoder_phys *phys;
+
+ dpu_enc = to_dpu_encoder_virt(drm_enc);
+
+ if (drm_enc->encoder_type == DRM_MODE_ENCODER_VIRTUAL) {
+ for (i = 0; i < dpu_enc->num_phys_encs; i++) {
+ phys = dpu_enc->phys_encs[i];
+ if (phys->ops.has_valid_output_fb && !phys->ops.has_valid_output_fb(phys)) {
+ DPU_DEBUG("invalid FB not kicking off\n");
+ return false;
+ }
+ }
+ }
+
+ return true;
+}
+
void dpu_encoder_kickoff(struct drm_encoder *drm_enc)
{
struct dpu_encoder_virt *dpu_enc;
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
index da5b6d6..63d90b8 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
@@ -187,4 +187,10 @@ void dpu_encoder_prepare_wb_job(struct drm_encoder *drm_enc,
void dpu_encoder_cleanup_wb_job(struct drm_encoder *drm_enc,
struct drm_writeback_job *job);
+/**
+ * dpu_encoder_has_valid_fb - cleanup writeback job for the encoder.
+ * @drm_enc: Pointer to drm encoder structure
+ */
+bool dpu_encoder_has_valid_fb(struct drm_encoder *drm_enc);
+
#endif /* __DPU_ENCODER_H__ */
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
index 80da0a9..5b45b3c 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
@@ -151,6 +151,7 @@ struct dpu_encoder_phys_ops {
struct drm_writeback_job *job);
void (*cleanup_wb_job)(struct dpu_encoder_phys *phys_enc,
struct drm_writeback_job *job);
+ bool (*has_valid_output_fb)(struct dpu_encoder_phys *phys_enc);
};
/**
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c
index 783f83e..7eeed79 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c
@@ -717,6 +717,16 @@ static void dpu_encoder_phys_wb_cleanup_wb_job(struct dpu_encoder_phys *phys_enc
wb_enc->wb_conn = NULL;
}
+static bool dpu_encoder_phys_wb_has_valid_fb(struct dpu_encoder_phys *phys_enc)
+{
+ struct dpu_encoder_phys_wb *wb_enc = to_dpu_encoder_phys_wb(phys_enc);
+
+ if (wb_enc->wb_job)
+ return true;
+ else
+ return false;
+}
+
/**
* dpu_encoder_phys_wb_init_ops - initialize writeback operations
* @ops: Pointer to encoder operation table
@@ -738,6 +748,8 @@ static void dpu_encoder_phys_wb_init_ops(struct dpu_encoder_phys_ops *ops)
ops->prepare_wb_job = dpu_encoder_phys_wb_prepare_wb_job;
ops->cleanup_wb_job = dpu_encoder_phys_wb_cleanup_wb_job;
ops->irq_control = dpu_encoder_phys_wb_irq_ctrl;
+ ops->has_valid_output_fb = dpu_encoder_phys_wb_has_valid_fb;
+
}
/**
--
With best wishes
Dmitry
