diff mbox series

[v5,2/6] drm/msm/dpu: adjust data width for widen bus case

Message ID 20240527-msm-drm-dsc-dsi-video-upstream-4-v5-2-f797ffba4682@linaro.org (mailing list archive)
State New, archived
Headers show
Series Add DSC support to DSI video panel | expand

Commit Message

Jun Nie May 27, 2024, 2:21 p.m. UTC
data is valid for only half the active window if widebus
is enabled

Signed-off-by: Jun Nie <jun.nie@linaro.org>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c | 9 +++++++++
 1 file changed, 9 insertions(+)

Comments

Dmitry Baryshkov May 28, 2024, 12:48 a.m. UTC | #1
On Mon, May 27, 2024 at 10:21:48PM +0800, Jun Nie wrote:
> data is valid for only half the active window if widebus
> is enabled
> 
> Signed-off-by: Jun Nie <jun.nie@linaro.org>
> ---
>  drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> index 225c1c7768ff..f97221423249 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> @@ -168,6 +168,15 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *intf,
>  
>  	data_width = p->width;
>  
> +	/*
> +	 * If widebus is enabled, data is valid for only half the active window
> +	 * since the data rate is doubled in this mode. But for the compression
> +	 * mode in DP case, the p->width is already adjusted in
> +	 * drm_mode_to_intf_timing_params()

Is there any reason for divergence here?

> +	 */
> +	if (p->wide_bus_en && !dp_intf)
> +		data_width = p->width >> 1;
> +
>  	hsync_data_start_x = hsync_start_x;
>  	hsync_data_end_x =  hsync_start_x + data_width - 1;
>  
> 
> -- 
> 2.34.1
>
Jun Nie May 28, 2024, 9:59 a.m. UTC | #2
Dmitry Baryshkov <dmitry.baryshkov@linaro.org> 于2024年5月28日周二 08:48写道:
>
> On Mon, May 27, 2024 at 10:21:48PM +0800, Jun Nie wrote:
> > data is valid for only half the active window if widebus
> > is enabled
> >
> > Signed-off-by: Jun Nie <jun.nie@linaro.org>
> > ---
> >  drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c | 9 +++++++++
> >  1 file changed, 9 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> > index 225c1c7768ff..f97221423249 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> > @@ -168,6 +168,15 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *intf,
> >
> >       data_width = p->width;
> >
> > +     /*
> > +      * If widebus is enabled, data is valid for only half the active window
> > +      * since the data rate is doubled in this mode. But for the compression
> > +      * mode in DP case, the p->width is already adjusted in
> > +      * drm_mode_to_intf_timing_params()
>
> Is there any reason for divergence here?

Lots of parameters in dpu_hw_intf_setup_timing_engine() is calculated
from timing->width,
such as hsync_period and display_v_start. So the width cannot be
adjusted beforehand in
drm_mode_to_intf_timing_params(). Otherwise, we get below error.

I guess the interface timing configuration differ in silicon, thus the
software shall handle the
difference. If we adjust the width beforehand for DSI, we get below error.

[    6.625446] [drm:dpu_encoder_frame_done_timeout:2469] [dpu
error]enc31 frame done timeout
[    6.642369] [drm:dpu_encoder_phys_vid_wait_for_commit_done:525]
[dpu error]vblank timeout: 4200c1
[    6.642395] [drm:dpu_kms_wait_for_commit_done:493] [dpu error]wait
for commit done returned -110


>
> > +      */
> > +     if (p->wide_bus_en && !dp_intf)
> > +             data_width = p->width >> 1;
> > +
> >       hsync_data_start_x = hsync_start_x;
> >       hsync_data_end_x =  hsync_start_x + data_width - 1;
> >
> >
> > --
> > 2.34.1
> >
>
> --
> With best wishes
> Dmitry
Dmitry Baryshkov May 28, 2024, 11:56 a.m. UTC | #3
On Tue, May 28, 2024 at 05:59:13PM +0800, Jun Nie wrote:
> Dmitry Baryshkov <dmitry.baryshkov@linaro.org> 于2024年5月28日周二 08:48写道:
> >
> > On Mon, May 27, 2024 at 10:21:48PM +0800, Jun Nie wrote:
> > > data is valid for only half the active window if widebus
> > > is enabled
> > >
> > > Signed-off-by: Jun Nie <jun.nie@linaro.org>
> > > ---
> > >  drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c | 9 +++++++++
> > >  1 file changed, 9 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> > > index 225c1c7768ff..f97221423249 100644
> > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> > > @@ -168,6 +168,15 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *intf,
> > >
> > >       data_width = p->width;
> > >
> > > +     /*
> > > +      * If widebus is enabled, data is valid for only half the active window
> > > +      * since the data rate is doubled in this mode. But for the compression
> > > +      * mode in DP case, the p->width is already adjusted in
> > > +      * drm_mode_to_intf_timing_params()
> >
> > Is there any reason for divergence here?
> 
> Lots of parameters in dpu_hw_intf_setup_timing_engine() is calculated
> from timing->width,
> such as hsync_period and display_v_start. So the width cannot be
> adjusted beforehand in
> drm_mode_to_intf_timing_params(). Otherwise, we get below error.
> 
> I guess the interface timing configuration differ in silicon, thus the
> software shall handle the
> difference. If we adjust the width beforehand for DSI, we get below error.
> 
> [    6.625446] [drm:dpu_encoder_frame_done_timeout:2469] [dpu
> error]enc31 frame done timeout
> [    6.642369] [drm:dpu_encoder_phys_vid_wait_for_commit_done:525]
> [dpu error]vblank timeout: 4200c1
> [    6.642395] [drm:dpu_kms_wait_for_commit_done:493] [dpu error]wait
> for commit done returned -110
> 

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Jessica Zhang May 28, 2024, 11:07 p.m. UTC | #4
On 5/27/2024 7:21 AM, Jun Nie wrote:
> data is valid for only half the active window if widebus
> is enabled
> 
> Signed-off-by: Jun Nie <jun.nie@linaro.org>

Hi Jun,

Reviewed-by: Jessica Zhang <quic_jesszhan@quicinc.com>

Thanks,

Jessica Zhang

> ---
>   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c | 9 +++++++++
>   1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> index 225c1c7768ff..f97221423249 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
> @@ -168,6 +168,15 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *intf,
>   
>   	data_width = p->width;
>   
> +	/*
> +	 * If widebus is enabled, data is valid for only half the active window
> +	 * since the data rate is doubled in this mode. But for the compression
> +	 * mode in DP case, the p->width is already adjusted in
> +	 * drm_mode_to_intf_timing_params()
> +	 */
> +	if (p->wide_bus_en && !dp_intf)
> +		data_width = p->width >> 1;
> +
>   	hsync_data_start_x = hsync_start_x;
>   	hsync_data_end_x =  hsync_start_x + data_width - 1;
>   
> 
> -- 
> 2.34.1
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
index 225c1c7768ff..f97221423249 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c
@@ -168,6 +168,15 @@  static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *intf,
 
 	data_width = p->width;
 
+	/*
+	 * If widebus is enabled, data is valid for only half the active window
+	 * since the data rate is doubled in this mode. But for the compression
+	 * mode in DP case, the p->width is already adjusted in
+	 * drm_mode_to_intf_timing_params()
+	 */
+	if (p->wide_bus_en && !dp_intf)
+		data_width = p->width >> 1;
+
 	hsync_data_start_x = hsync_start_x;
 	hsync_data_end_x =  hsync_start_x + data_width - 1;