From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Cc: linux-renesas-soc@vger.kernel.org,
dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/4] drm: rcar-du: mipi-dsi: Ensure correct fout is reported
Date: Tue, 30 Nov 2021 05:13:06 +0200 [thread overview]
Message-ID: <YaWWwhadGi8Hx/Ar@pendragon.ideasonboard.com> (raw)
In-Reply-To: <20211126101518.938783-4-kieran.bingham+renesas@ideasonboard.com>
Hi Kieran,
Thank you for the patch.
On Fri, Nov 26, 2021 at 10:15:17AM +0000, Kieran Bingham wrote:
> The debug reporting for the clock calculations was erroneously reporting
> the last calculation of fout, rather than the fout that was determined
> to have the least error, and therefore be the values chosen to operate
> with.
>
> Fix the reporting to show the correct output by storing the determined
> fout, along with the error value.
>
> Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
> ---
>
> I spent /way/ too long confused why my clock values didn't make sense
> before I noticed this.. :-(
Oops :-S Sorry about that.
> drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c b/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c
> index e94245029f95..833f4480bdf3 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c
> +++ b/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c
> @@ -168,6 +168,7 @@ static int rcar_mipi_dsi_phtw_test(struct rcar_mipi_dsi *dsi, u32 phtw)
> */
>
> struct dsi_setup_info {
> + unsigned long fout;
> unsigned int err;
> u16 vco_cntrl;
> u16 prop_cntrl;
> @@ -247,6 +248,7 @@ static void rcar_mipi_dsi_parameters_calc(struct rcar_mipi_dsi *dsi,
> setup_info->m = m - 2;
> setup_info->n = n - 1;
> setup_info->err = err;
> + setup_info->fout = fout;
> if (err == 0)
> goto done;
> }
> @@ -256,7 +258,7 @@ static void rcar_mipi_dsi_parameters_calc(struct rcar_mipi_dsi *dsi,
> done:
> dev_dbg(dsi->dev,
> "%pC %lu Hz -> Fout %lu Hz (target %lu Hz, error %d.%02u%%), PLL M/N/DIV %u/%u/%u\n",
> - clk, fin, fout, fout_target, setup_info->err / 100,
> + clk, fin, setup_info->fout, fout_target, setup_info->err / 100,
We don't need the fout in the caller, so it could be a local variable
(best_fout for instance). I can however imagine that we the frequency
could become useful in the caller, so
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> setup_info->err % 100, setup_info->m,
> setup_info->n, setup_info->div);
> dev_dbg(dsi->dev,
--
Regards,
Laurent Pinchart
next prev parent reply other threads:[~2021-11-30 3:13 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-26 10:15 [PATCH 0/4] drm: rcar-du: mipi-dsi: Cleanup and Fixes Kieran Bingham
2021-11-26 10:15 ` [PATCH 1/4] drm: rcar-du: Fix Makefile indentation for DSI Kieran Bingham
2021-11-30 2:40 ` Laurent Pinchart
2021-11-26 10:15 ` [PATCH 2/4] drm: rcar-du: Select DRM_MIPI_DSI with DRM_RCAR_MIPI_DSI Kieran Bingham
2021-11-30 2:52 ` Laurent Pinchart
2021-11-26 10:15 ` [PATCH 3/4] drm: rcar-du: mipi-dsi: Ensure correct fout is reported Kieran Bingham
2021-11-30 3:13 ` Laurent Pinchart [this message]
2021-11-26 10:15 ` [PATCH 4/4] drm: rcar-du: mipi-dsi: Support bridge probe ordering Kieran Bingham
2021-11-26 10:51 ` Biju Das
2021-11-30 3:24 ` Laurent Pinchart
2021-11-30 7:38 ` Jagan Teki
2021-11-30 16:01 ` Kieran Bingham
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=YaWWwhadGi8Hx/Ar@pendragon.ideasonboard.com \
--to=laurent.pinchart@ideasonboard.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=kieran.bingham+renesas@ideasonboard.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-renesas-soc@vger.kernel.org \
/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).