drm: mxsfb_crtc: Fix the framebuffer misplacement

Commit Message

Fabio Estevam Feb. 2, 2017, 9:26 p.m. UTC

From: Fabio Estevam <[e-mail]>

Currently the framebuffer content is displayed with incorrect offsets
in both the vertical and horizontal directions.

The fbdev version of the driver does not show this problem. Breno Lima
dumped the eLCDIF controller registers on both the drm and fbdev drivers
and noticed that the VDCTRL3 register is configured incorrectly in the
drm driver.

The fbdev driver calculates the vertical and horizontal wait counts
of the VDCTRL3 register by doing: back porch + sync length.

Looking at the horizontal and vertical timing diagram from 
include/drm/drm_modes.h this value corresponds to:

crtc_[hv]total - crtc_[hv]sync_start

So fix the VDCTRL3 register setting accordingly so that the eLCDIF
controller can properly show the framebuffer content in the correct
position.

Reported-by: Breno Lima <[e-mail]>
Signed-off-by: Fabio Estevam <[e-mail]>
---
 drivers/gpu/drm/mxsfb/mxsfb_crtc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Breno Matheus Lima Feb. 2, 2017, 10:28 p.m. UTC | #1

2017-02-02 19:26 GMT-02:00 Fabio Estevam <[e-mail]>:
>
> From: Fabio Estevam <[e-mail]>
>
> Currently the framebuffer content is displayed with incorrect offsets
> in both the vertical and horizontal directions.
>
> The fbdev version of the driver does not show this problem. Breno Lima
> dumped the eLCDIF controller registers on both the drm and fbdev drivers
> and noticed that the VDCTRL3 register is configured incorrectly in the
> drm driver.
>
> The fbdev driver calculates the vertical and horizontal wait counts
> of the VDCTRL3 register by doing: back porch + sync length.
>
> Looking at the horizontal and vertical timing diagram from
> include/drm/drm_modes.h this value corresponds to:
>
> crtc_[hv]total - crtc_[hv]sync_start
>
> So fix the VDCTRL3 register setting accordingly so that the eLCDIF
> controller can properly show the framebuffer content in the correct
> position.
>
> Reported-by: Breno Lima <[e-mail]>
> Signed-off-by: Fabio Estevam <[e-mail]>
> ---
>  drivers/gpu/drm/mxsfb/mxsfb_crtc.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
> index e10a4ed..b56f86c 100644
> --- a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
> +++ b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
> @@ -184,8 +184,8 @@ static void mxsfb_crtc_mode_set_nofb(struct
mxsfb_drm_private *mxsfb)
>                VDCTRL2_SET_HSYNC_PERIOD(m->crtc_htotal),
>                mxsfb->base + LCDC_VDCTRL2);
>
> -       writel(SET_HOR_WAIT_CNT(m->crtc_hblank_end - m->crtc_hsync_end) |
> -             SET_VERT_WAIT_CNT(m->crtc_vblank_end - m->crtc_vsync_end),
> +       writel(SET_HOR_WAIT_CNT(m->crtc_htotal - m->crtc_hsync_start) |
> +              SET_VERT_WAIT_CNT(m->crtc_vtotal - m->crtc_vsync_start),
>                mxsfb->base + LCDC_VDCTRL3);
>
>         writel(SET_DOTCLK_H_VALID_DATA_CNT(m->hdisplay),
> --
> 2.7.4
>

Tested-by: Breno Lima <[e-mail]>

Marek Vasut Feb. 7, 2017, 9:44 p.m. UTC | #2

On 02/02/2017 10:26 PM, Fabio Estevam wrote:
> From: Fabio Estevam <[e-mail]>
> 
> Currently the framebuffer content is displayed with incorrect offsets
> in both the vertical and horizontal directions.
> 
> The fbdev version of the driver does not show this problem. Breno Lima
> dumped the eLCDIF controller registers on both the drm and fbdev drivers
> and noticed that the VDCTRL3 register is configured incorrectly in the
> drm driver.
> 
> The fbdev driver calculates the vertical and horizontal wait counts
> of the VDCTRL3 register by doing: back porch + sync length.
> 
> Looking at the horizontal and vertical timing diagram from 
> include/drm/drm_modes.h this value corresponds to:
> 
> crtc_[hv]total - crtc_[hv]sync_start
> 
> So fix the VDCTRL3 register setting accordingly so that the eLCDIF
> controller can properly show the framebuffer content in the correct
> position.
> 
> Reported-by: Breno Lima <[e-mail]>
> Signed-off-by: Fabio Estevam <[e-mail]>

Tested-by: Marek Vasut <[e-mail]>

Daniel Vetter Feb. 7, 2017, 10:15 p.m. UTC | #3

On Tue, Feb 07, 2017 at 10:44:59PM +0100, Marek Vasut wrote:
> On 02/02/2017 10:26 PM, Fabio Estevam wrote:
> > From: Fabio Estevam <[e-mail]>
> > 
> > Currently the framebuffer content is displayed with incorrect offsets
> > in both the vertical and horizontal directions.
> > 
> > The fbdev version of the driver does not show this problem. Breno Lima
> > dumped the eLCDIF controller registers on both the drm and fbdev drivers
> > and noticed that the VDCTRL3 register is configured incorrectly in the
> > drm driver.
> > 
> > The fbdev driver calculates the vertical and horizontal wait counts
> > of the VDCTRL3 register by doing: back porch + sync length.
> > 
> > Looking at the horizontal and vertical timing diagram from 
> > include/drm/drm_modes.h this value corresponds to:
> > 
> > crtc_[hv]total - crtc_[hv]sync_start
> > 
> > So fix the VDCTRL3 register setting accordingly so that the eLCDIF
> > controller can properly show the framebuffer content in the correct
> > position.
> > 
> > Reported-by: Breno Lima <[e-mail]>
> > Signed-off-by: Fabio Estevam <[e-mail]>
> 
> Tested-by: Marek Vasut <[e-mail]>

You're listed as maintainer in MAINTAINERS, replying with tested-by is
super confusing. Did you pick this up and will do a pull request? Do you
expect someone else to pick this up?
-Daniel

Marek Vasut Feb. 7, 2017, 10:31 p.m. UTC | #4

On 02/07/2017 11:15 PM, Daniel Vetter wrote:
> On Tue, Feb 07, 2017 at 10:44:59PM +0100, Marek Vasut wrote:
>> On 02/02/2017 10:26 PM, Fabio Estevam wrote:
>>> From: Fabio Estevam <[e-mail]>
>>>
>>> Currently the framebuffer content is displayed with incorrect offsets
>>> in both the vertical and horizontal directions.
>>>
>>> The fbdev version of the driver does not show this problem. Breno Lima
>>> dumped the eLCDIF controller registers on both the drm and fbdev drivers
>>> and noticed that the VDCTRL3 register is configured incorrectly in the
>>> drm driver.
>>>
>>> The fbdev driver calculates the vertical and horizontal wait counts
>>> of the VDCTRL3 register by doing: back porch + sync length.
>>>
>>> Looking at the horizontal and vertical timing diagram from 
>>> include/drm/drm_modes.h this value corresponds to:
>>>
>>> crtc_[hv]total - crtc_[hv]sync_start
>>>
>>> So fix the VDCTRL3 register setting accordingly so that the eLCDIF
>>> controller can properly show the framebuffer content in the correct
>>> position.
>>>
>>> Reported-by: Breno Lima <[e-mail]>
>>> Signed-off-by: Fabio Estevam <[e-mail]>
>>
>> Tested-by: Marek Vasut <[e-mail]>
> 
> You're listed as maintainer in MAINTAINERS, replying with tested-by is
> super confusing. Did you pick this up and will do a pull request?

No

> Do you expect someone else to pick this up?

The last patches for mxsfb were picked by you, but if you expect me to
pick the mxsfb patches through my own tree and then submit PR, I can do
that.

Daniel Vetter Feb. 8, 2017, 7:17 a.m. UTC | #5

On Tue, Feb 7, 2017 at 11:31 PM, Marek Vasut <[e-mail]> wrote:
> On 02/07/2017 11:15 PM, Daniel Vetter wrote:
>> On Tue, Feb 07, 2017 at 10:44:59PM +0100, Marek Vasut wrote:
>>> On 02/02/2017 10:26 PM, Fabio Estevam wrote:
>>>> From: Fabio Estevam <[e-mail]>
>>>>
>>>> Currently the framebuffer content is displayed with incorrect offsets
>>>> in both the vertical and horizontal directions.
>>>>
>>>> The fbdev version of the driver does not show this problem. Breno Lima
>>>> dumped the eLCDIF controller registers on both the drm and fbdev drivers
>>>> and noticed that the VDCTRL3 register is configured incorrectly in the
>>>> drm driver.
>>>>
>>>> The fbdev driver calculates the vertical and horizontal wait counts
>>>> of the VDCTRL3 register by doing: back porch + sync length.
>>>>
>>>> Looking at the horizontal and vertical timing diagram from
>>>> include/drm/drm_modes.h this value corresponds to:
>>>>
>>>> crtc_[hv]total - crtc_[hv]sync_start
>>>>
>>>> So fix the VDCTRL3 register setting accordingly so that the eLCDIF
>>>> controller can properly show the framebuffer content in the correct
>>>> position.
>>>>
>>>> Reported-by: Breno Lima <[e-mail]>
>>>> Signed-off-by: Fabio Estevam <[e-mail]>
>>>
>>> Tested-by: Marek Vasut <[e-mail]>
>>
>> You're listed as maintainer in MAINTAINERS, replying with tested-by is
>> super confusing. Did you pick this up and will do a pull request?
>
> No
>
>> Do you expect someone else to pick this up?
>
> The last patches for mxsfb were picked by you, but if you expect me to
> pick the mxsfb patches through my own tree and then submit PR, I can do
> that.

I apply trivial patches as a welcoming gesture for new folks, but
that's generally about it. Anyway, if you expect drm-misc maintainers
to pick up stuff then you need to tell us, otherwise the patch will be
lost. But then if you want mxsfb maintained in drm-misc I'd say better
to get commit rights and join the club :-) Just ping on #dri-devel on
freenode.
-Daniel

Marek Vasut Feb. 8, 2017, 10:17 a.m. UTC | #6

On 02/08/2017 08:17 AM, Daniel Vetter wrote:
> On Tue, Feb 7, 2017 at 11:31 PM, Marek Vasut <[e-mail]> wrote:
>> On 02/07/2017 11:15 PM, Daniel Vetter wrote:
>>> On Tue, Feb 07, 2017 at 10:44:59PM +0100, Marek Vasut wrote:
>>>> On 02/02/2017 10:26 PM, Fabio Estevam wrote:
>>>>> From: Fabio Estevam <[e-mail]>
>>>>>
>>>>> Currently the framebuffer content is displayed with incorrect offsets
>>>>> in both the vertical and horizontal directions.
>>>>>
>>>>> The fbdev version of the driver does not show this problem. Breno Lima
>>>>> dumped the eLCDIF controller registers on both the drm and fbdev drivers
>>>>> and noticed that the VDCTRL3 register is configured incorrectly in the
>>>>> drm driver.
>>>>>
>>>>> The fbdev driver calculates the vertical and horizontal wait counts
>>>>> of the VDCTRL3 register by doing: back porch + sync length.
>>>>>
>>>>> Looking at the horizontal and vertical timing diagram from
>>>>> include/drm/drm_modes.h this value corresponds to:
>>>>>
>>>>> crtc_[hv]total - crtc_[hv]sync_start
>>>>>
>>>>> So fix the VDCTRL3 register setting accordingly so that the eLCDIF
>>>>> controller can properly show the framebuffer content in the correct
>>>>> position.
>>>>>
>>>>> Reported-by: Breno Lima <[e-mail]>
>>>>> Signed-off-by: Fabio Estevam <[e-mail]>
>>>>
>>>> Tested-by: Marek Vasut <[e-mail]>
>>>
>>> You're listed as maintainer in MAINTAINERS, replying with tested-by is
>>> super confusing. Did you pick this up and will do a pull request?
>>
>> No
>>
>>> Do you expect someone else to pick this up?
>>
>> The last patches for mxsfb were picked by you, but if you expect me to
>> pick the mxsfb patches through my own tree and then submit PR, I can do
>> that.
> 
> I apply trivial patches as a welcoming gesture for new folks, but
> that's generally about it. Anyway, if you expect drm-misc maintainers
> to pick up stuff then you need to tell us, otherwise the patch will be
> lost. But then if you want mxsfb maintained in drm-misc I'd say better
> to get commit rights and join the club :-) Just ping on #dri-devel on
> freenode.

Ha, I see. I'll ping you on dri-devel shortly.

> -Daniel
>

Patch

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
index e10a4ed..b56f86c 100644
--- a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
@@ -184,8 +184,8 @@  static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
 	       VDCTRL2_SET_HSYNC_PERIOD(m->crtc_htotal),
 	       mxsfb->base + LCDC_VDCTRL2);
 
-	writel(SET_HOR_WAIT_CNT(m->crtc_hblank_end - m->crtc_hsync_end) |
-	       SET_VERT_WAIT_CNT(m->crtc_vblank_end - m->crtc_vsync_end),
+	writel(SET_HOR_WAIT_CNT(m->crtc_htotal - m->crtc_hsync_start) |
+	       SET_VERT_WAIT_CNT(m->crtc_vtotal - m->crtc_vsync_start),
 	       mxsfb->base + LCDC_VDCTRL3);
 
 	writel(SET_DOTCLK_H_VALID_DATA_CNT(m->hdisplay),