This is a note to let you know that I've just added the patch titled
media: rkvdec: Stop overclocking the decoder
to the 5.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
media-rkvdec-stop-overclocking-the-decoder.patch
and it can be found in the queue-5.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 3440e227b08784c954abb2bb540d931e22d0d675
Author: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx>
Date: Fri May 13 22:29:10 2022 +0200
media: rkvdec: Stop overclocking the decoder
[ Upstream commit 9998943f6dfc5d5472bfab2e38527fb6ba5e9da7 ]
While this overclock hack seems to work on some implementations
(some ChromeBooks, RockPi4) it also causes instability on other
implementations (notably LibreComputer Renegade, but there were more
reports in the LibreELEC project, where this has been removed). While
performance is indeed affected (tested with GStreamer), 4K playback
still works as long as you don't operate in lock step and keep at
least 1 frame ahead of time in the decode queue.
After discussion with ChromeOS members, it would seem that their
implementation indeed used to synchronously decode each frame, so
this hack was simply compensating for their code being less
efficient. In my opinion, this hack should not have been included
upstream.
Fixes: cd33c830448ba ("media: rkvdec: Add the rkvdec driver")
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx>
Reviewed-by: Sebastian Fricke <sebastian.fricke@xxxxxxxxxxxxx>
Reviewed-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/staging/media/rkvdec/rkvdec.c b/drivers/staging/media/rkvdec/rkvdec.c
index c0cf3488f970..2df8cf4883e2 100644
--- a/drivers/staging/media/rkvdec/rkvdec.c
+++ b/drivers/staging/media/rkvdec/rkvdec.c
@@ -1027,12 +1027,6 @@ static int rkvdec_probe(struct platform_device *pdev)
if (ret)
return ret;
- /*
- * Bump ACLK to max. possible freq. (500 MHz) to improve performance
- * When 4k video playback.
- */
- clk_set_rate(rkvdec->clocks[0].clk, 500 * 1000 * 1000);
-
rkvdec->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(rkvdec->regs))
return PTR_ERR(rkvdec->regs);
