On 1/24/2023 11:29 PM, Dmitry Baryshkov wrote:
On Wed, 25 Jan 2023 at 04:14, Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> wrote:
On 6/17/2022 4:33 PM, Dmitry Baryshkov wrote:
The array of CRTC in the struct msm_drm_private duplicates a list of
CRTCs in the drm_device. Drop it and use the existing list for CRTC
enumeration.
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 2 +-
drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c | 2 +-
drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c | 2 +-
drivers/gpu/drm/msm/msm_drv.c | 44 +++++++++++++-----------
drivers/gpu/drm/msm/msm_drv.h | 3 +-
5 files changed, 27 insertions(+), 26 deletions(-)
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index e23e2552e802..e79f0a8817ac 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -806,7 +806,7 @@ static int _dpu_kms_drm_obj_init(struct dpu_kms *dpu_kms)
ret = PTR_ERR(crtc);
return ret;
}
- priv->crtcs[priv->num_crtcs++] = crtc;
+ priv->num_crtcs++;
}
/* All CRTCs are compatible with all encoders */
diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
index fb48c8c19ec3..7449c1693e45 100644
--- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
+++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c
@@ -337,7 +337,7 @@ static int modeset_init(struct mdp4_kms *mdp4_kms)
goto fail;
}
- priv->crtcs[priv->num_crtcs++] = crtc;
+ priv->num_crtcs++;
}
/*
diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
index 3d5621a68f85..36808990f840 100644
--- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
+++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
@@ -497,7 +497,7 @@ static int modeset_init(struct mdp5_kms *mdp5_kms)
DRM_DEV_ERROR(dev->dev, "failed to construct crtc %d (%d)\n", i, ret);
goto fail;
}
- priv->crtcs[priv->num_crtcs++] = crtc;
+ priv->num_crtcs++;
}
/*
diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 1aab6bf86278..567e77dae43b 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -149,7 +149,7 @@ static void msm_irq_uninstall(struct drm_device *dev)
struct msm_vblank_work {
struct work_struct work;
- int crtc_id;
+ struct drm_crtc *crtc;
bool enable;
struct msm_drm_private *priv;
};
@@ -162,15 +162,15 @@ static void vblank_ctrl_worker(struct work_struct *work)
struct msm_kms *kms = priv->kms;
Is there any chance of vbl_work->crtc becoming NULL before this gets
executed?
No. The worker is created in vblank_ctrl_queue_work. The
vbl_work->crtc is filled at the time of creation.
So do we need to protect this like
if (vbl_work->enable && vbl_work->crtc)
Because the layers below this dont seem to have NULL protection.
if (vbl_work->enable)
- kms->funcs->enable_vblank(kms, priv->crtcs[vbl_work->crtc_id]);
+ kms->funcs->enable_vblank(kms, vbl_work->crtc);
else
- kms->funcs->disable_vblank(kms, priv->crtcs[vbl_work->crtc_id]);
+ kms->funcs->disable_vblank(kms, vbl_work->crtc);
kfree(vbl_work);
}
static int vblank_ctrl_queue_work(struct msm_drm_private *priv,
- int crtc_id, bool enable)
+ struct drm_crtc *crtc, bool enable)
{
struct msm_vblank_work *vbl_work;
@@ -180,7 +180,7 @@ static int vblank_ctrl_queue_work(struct msm_drm_private *priv,
INIT_WORK(&vbl_work->work, vblank_ctrl_worker);
- vbl_work->crtc_id = crtc_id;
+ vbl_work->crtc = crtc;
vbl_work->enable = enable;
vbl_work->priv = priv;
@@ -354,7 +354,8 @@ static int msm_drm_init(struct device *dev, const struct drm_driver *drv)
struct msm_drm_private *priv = dev_get_drvdata(dev);
struct drm_device *ddev;
struct msm_kms *kms;
- int ret, i;
+ struct drm_crtc *crtc;
+ int ret;
if (drm_firmware_drivers_only())
return -ENODEV;
@@ -427,20 +428,23 @@ static int msm_drm_init(struct device *dev, const struct drm_driver *drv)
ddev->mode_config.funcs = &mode_config_funcs;
ddev->mode_config.helper_private = &mode_config_helper_funcs;
- for (i = 0; i < priv->num_crtcs; i++) {
+ drm_for_each_crtc(crtc, ddev) {
+ struct msm_drm_thread *ev_thread;
+
/* initialize event thread */
- priv->event_thread[i].crtc_id = priv->crtcs[i]->base.id;
- priv->event_thread[i].dev = ddev;
- priv->event_thread[i].worker = kthread_create_worker(0,
- "crtc_event:%d", priv->event_thread[i].crtc_id);
- if (IS_ERR(priv->event_thread[i].worker)) {
- ret = PTR_ERR(priv->event_thread[i].worker);
+ ev_thread = &priv->event_thread[drm_crtc_index(crtc)];
+ ev_thread->crtc = crtc;
+ ev_thread->dev = ddev;
+ ev_thread->worker = kthread_create_worker(0,
+ "crtc_event:%d", ev_thread->crtc->base.id);
Please correct me if wrong.
Today, other than just populating the name for the worker is the
ev_thread->crtc used anywhere?
If so, can we just drop crtc from msm_drm_thread and while creating the
worker just use kthread_create_worker(0, "crtc_event:%d", crtc->base.id);
It seems so. I'll take a look for v2.
However your questions actually raised another question in my head. I
went on looking for the reason for such complex vblank handling. It
was added by Hai Li in the commit 78b1d470d57d ("drm/msm: Enable
clocks during enable/disable_vblank() callbacks"). However I don't
fully understand why the code will toggle vblank handling while the
DPU/MDP5/MDP4 device is not resumed already. Maybe I just missed
something here. Do you know the story behind the change?
I dont know the history as it pre-dates my work in upstream.
But one use-case I can think of is for command mode panel.
Typically, command mode panel will disable the clocks during idle screen.
Now, if usermode wants to enable vsync, it will crash in the driver.
So driver needs to make sure what whenever hw vsync is toggled on/off,
the required clocks need to be enabled.
+ if (IS_ERR(ev_thread->worker)) {
+ ret = PTR_ERR(ev_thread->worker);
DRM_DEV_ERROR(dev, "failed to create crtc_event kthread\n");
- priv->event_thread[i].worker = NULL;
+ ev_thread->worker = NULL;
goto err_msm_uninit;
}
- sched_set_fifo(priv->event_thread[i].worker->task);
+ sched_set_fifo(ev_thread->worker->task);
}
ret = drm_vblank_init(ddev, priv->num_crtcs);
@@ -563,25 +567,23 @@ static void msm_postclose(struct drm_device *dev, struct drm_file *file)
int msm_crtc_enable_vblank(struct drm_crtc *crtc)
{
struct drm_device *dev = crtc->dev;
- unsigned int pipe = crtc->index;
struct msm_drm_private *priv = dev->dev_private;
struct msm_kms *kms = priv->kms;
if (!kms)
return -ENXIO;
- drm_dbg_vbl(dev, "crtc=%u", pipe);
- return vblank_ctrl_queue_work(priv, pipe, true);
+ drm_dbg_vbl(dev, "crtc=%u", crtc->base.id);
+ return vblank_ctrl_queue_work(priv, crtc, true);
}
void msm_crtc_disable_vblank(struct drm_crtc *crtc)
{
struct drm_device *dev = crtc->dev;
- unsigned int pipe = crtc->index;
struct msm_drm_private *priv = dev->dev_private;
struct msm_kms *kms = priv->kms;
if (!kms)
return;
- drm_dbg_vbl(dev, "crtc=%u", pipe);
- vblank_ctrl_queue_work(priv, pipe, false);
+ drm_dbg_vbl(dev, "crtc=%u", crtc->base.id);
+ vblank_ctrl_queue_work(priv, crtc, false);
}
/*
diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index 08388d742d65..0e98b6f161df 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -102,7 +102,7 @@ struct msm_display_topology {
/* Commit/Event thread specific structure */
struct msm_drm_thread {
struct drm_device *dev;
- unsigned int crtc_id;
+ struct drm_crtc *crtc;
struct kthread_worker *worker;
};
@@ -178,7 +178,6 @@ struct msm_drm_private {
struct workqueue_struct *wq;
unsigned int num_crtcs;
- struct drm_crtc *crtcs[MAX_CRTCS];
struct msm_drm_thread event_thread[MAX_CRTCS];
