From: Jagan Teki <jagan@amarulasolutions.com>
To: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Chen-Yu Tsai <wens@csie.org>, Icenowy Zheng <icenowy@aosc.io>,
Jernej Skrabec <jernej.skrabec@siol.net>,
Vasily Khoruzhick <anarsoul@gmail.com>,
Rob Herring <robh+dt@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will.deacon@arm.com>,
David Airlie <airlied@linux.ie>,
dri-devel <dri-devel@lists.freedesktop.org>,
Michael Turquette <mturquette@baylibre.com>,
Stephen Boyd <sboyd@kernel.org>,
linux-clk <linux-clk@vger.kernel.org>,
Michael Trimarchi <michael@amarulasolutions.com>,
linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
devicetree <devicetree@vger.kernel.org>,
linux-kernel <linux-kernel@vger.kernel.org>,
linux-sunxi <linux-sunxi@googlegroups.com>
Subject: Re: [PATCH 08/12] drm/sun4i: sun6i_mipi_dsi: Refactor vertical video start delay
Date: Thu, 27 Sep 2018 23:03:19 +0530 [thread overview]
Message-ID: <CAMty3ZDxpLwVDsgVMjX+6+uz89sQ1aZaXHHZ+-5aogrA4MHmqw@mail.gmail.com> (raw)
In-Reply-To: <20180927171451.7iqt2nt2log5qojf@flea>
On Thu, Sep 27, 2018 at 10:44 PM Maxime Ripard
<maxime.ripard@bootlin.com> wrote:
>
> On Thu, Sep 27, 2018 at 05:18:46PM +0530, Jagan Teki wrote:
> > Accordingly to BPI-M64-bsp DE DSI code Video start delay
> > can be computed by subtracting total vertical timing with
> > front porch timing and with adding 1 delay line for TCON.
>
> This is what the current code is doing as well.
The current code
return mode->vtotal - (mode->vsync_end - mode->vdisplay) + 1;
(mode->vsync_end - mode->vdisplay) = front porch + sync
but I'm updating here only front porch.
>
> > This patch simply add the start_delay logic from BPI-M64-bsp,
> > w/o this new computation, the DSI on A64 encounter vblank time out.
> >
> > [CRTC:36:crtc-0] vblank wait timed out
> >
> > Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> > ---
> > drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 12 +++++++++++-
> > 1 file changed, 11 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> > index 9918fdb990ff..217db74c6dc3 100644
> > --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> > +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> > @@ -358,7 +358,17 @@ static void sun6i_dsi_inst_init(struct sun6i_dsi *dsi,
> > static u16 sun6i_dsi_get_video_start_delay(struct sun6i_dsi *dsi,
> > struct drm_display_mode *mode)
> > {
> > - return mode->vtotal - (mode->vsync_end - mode->vdisplay) + 1;
> > + u32 vfp = mode->vsync_start - mode->vdisplay;
let me explain this.
Actual code from Allwinner
u32 vfp = panel->lcd_vt - panel->lcd_y - panel->lcd_vbp;
So,
=> (panel->lcd_vt - panel->lcd_y) - (panel->lcd_vbp)
=> (front porch + sync + back porch) - (back porch + sync)
=> front porch + sync + back porch - back porch - sync
=> front porch
=> mode->vsync_start - mode->vdisplay
Hope it clear.
next prev parent reply other threads:[~2018-09-27 17:33 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-27 11:48 [PATCH 00/12] drm/sun4i: Allwinner A64 MIPI-DSI support Jagan Teki
2018-09-27 11:48 ` [PATCH 01/12] clk: sunxi-ng: a64: Fix gate bit of DSI DPHY Jagan Teki
2018-09-27 11:48 ` [PATCH 02/12] drm/sun4i: sun6i_mipi_dsi: Add Allwinner A64 MIPI DSI support Jagan Teki
2018-09-27 11:48 ` [PATCH 03/12] dt-bindings: sun6i-dsi: Add compatible for A64 MIPI DSI Jagan Teki
2018-10-15 18:24 ` Rob Herring
2018-09-27 11:48 ` [PATCH 04/12] drm/sun4i: sun6i_mipi_dsi: Enable missing DSI bus clock Jagan Teki
2018-09-27 12:42 ` Chen-Yu Tsai
2018-09-27 13:44 ` Jagan Teki
2018-09-27 14:16 ` [linux-sunxi] " Chen-Yu Tsai
2018-09-27 16:26 ` Jagan Teki
2018-09-27 16:33 ` Chen-Yu Tsai
2018-09-27 11:48 ` [PATCH 05/12] drm/sun4i: sun6i_mipi_dsi: Add DSI Generic short write 2 param transfer Jagan Teki
2018-09-27 17:18 ` Maxime Ripard
2018-09-27 17:36 ` Jagan Teki
2018-09-29 13:47 ` Maxime Ripard
2018-09-27 11:48 ` [PATCH 06/12] drm/sun4i: sun6i_mipi_dsi: Fix VBP size calculation Jagan Teki
2018-09-27 15:21 ` Maxime Ripard
2018-09-27 16:20 ` Jagan Teki
2018-09-29 13:53 ` Maxime Ripard
2018-10-01 8:09 ` [linux-sunxi] " Jagan Teki
2018-10-08 15:05 ` Maxime Ripard
2018-09-27 11:48 ` [PATCH 07/12] drm/sun4i: sun6i_mipi_dsi: Fix TCON DRQ set bits Jagan Teki
2018-09-27 16:58 ` Maxime Ripard
2018-09-27 17:45 ` Jagan Teki
2018-10-02 13:20 ` Maxime Ripard
2018-10-03 3:22 ` [linux-sunxi] " Jagan Teki
2018-10-08 15:05 ` Maxime Ripard
2018-09-27 11:48 ` [PATCH 08/12] drm/sun4i: sun6i_mipi_dsi: Refactor vertical video start delay Jagan Teki
2018-09-27 17:14 ` Maxime Ripard
2018-09-27 17:33 ` Jagan Teki [this message]
2018-09-29 15:27 ` Maxime Ripard
2018-10-01 7:55 ` [linux-sunxi] " Jagan Teki
2018-10-02 13:29 ` Maxime Ripard
2018-09-27 11:48 ` [PATCH 09/12] dt-bindings: panel: Add Bananapi S070WV20-CT16 MIPI-DSI panel bindings Jagan Teki
2018-10-15 18:24 ` Rob Herring
2018-10-22 10:22 ` Chen-Yu Tsai
2018-10-23 15:11 ` Rob Herring
2018-10-24 20:22 ` Chen-Yu Tsai
2018-09-27 11:48 ` [PATCH 10/12] drm/panel: Add Bananapi S070WV20-CT16 MIPI-DSI panel driver Jagan Teki
2018-09-28 4:32 ` Chen-Yu Tsai
2018-10-04 16:06 ` Jagan Teki
2018-09-27 11:48 ` [PATCH 11/12] arm64: dts: allwinner: a64: Add DSI pipeline Jagan Teki
2018-09-27 17:16 ` Maxime Ripard
2018-09-27 11:48 ` [PATCH 12/12] arm64: dts: allwinner: bananapi-m64: Bananapi S070WV20-CT16 DSI panel Jagan Teki
2018-09-27 17:17 ` Maxime Ripard
2018-10-04 16:03 ` Jagan Teki
2018-10-05 15:31 ` Maxime Ripard
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAMty3ZDxpLwVDsgVMjX+6+uz89sQ1aZaXHHZ+-5aogrA4MHmqw@mail.gmail.com \
--to=jagan@amarulasolutions.com \
--cc=airlied@linux.ie \
--cc=anarsoul@gmail.com \
--cc=catalin.marinas@arm.com \
--cc=devicetree@vger.kernel.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=icenowy@aosc.io \
--cc=jernej.skrabec@siol.net \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-clk@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-sunxi@googlegroups.com \
--cc=mark.rutland@arm.com \
--cc=maxime.ripard@bootlin.com \
--cc=michael@amarulasolutions.com \
--cc=mturquette@baylibre.com \
--cc=robh+dt@kernel.org \
--cc=sboyd@kernel.org \
--cc=wens@csie.org \
--cc=will.deacon@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).