Re: [PATCH] mmc: host: mtk-sd: enable recheck_sdio_irq for MT8516 SoC

From: Ulf Hansson <ulf.hansson@linaro.org>
To: "yong.mao@mediatek.com" <yong.mao@mediatek.com>
Cc: Mattijs Korpershoek <mkorpershoek@baylibre.com>,
	Fabien Parent <fparent@baylibre.com>,
	Chaotian Jing <chaotian.jing@mediatek.com>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	"linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>,
	"moderated list:ARM/Mediatek SoC support" 
	<linux-mediatek@lists.infradead.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH] mmc: host: mtk-sd: enable recheck_sdio_irq for MT8516 SoC
Date: Wed, 28 Oct 2020 10:40:42 +0100	[thread overview]
Message-ID: <CAPDyKFrjov40BxHRrG6WoUVLaVbPbvPPf_ot2xybVEfGerST9g@mail.gmail.com> (raw)
In-Reply-To: <1603869682.6198.23.camel@mhfsdcap03>

On Wed, 28 Oct 2020 at 08:22, yong.mao@mediatek.com
<yong.mao@mediatek.com> wrote:
>
> On Tue, 2020-10-27 at 13:44 +0100, Mattijs Korpershoek wrote:
> > Hi Ulf,
> >
> > Ulf Hansson <ulf.hansson@linaro.org> writes:
> >
> > > + Yong Mao, Chaotian Jing
> > >
> > > On Fri, 23 Oct 2020 at 14:29, Fabien Parent <fparent@baylibre.com> wrote:
> > >>
> > >> MT8516 SoC suffers from sometimes losing SDIO IRQs, this makes SDIO
> > >> devices sometimes unstable. Make use of the new property
> > >> recheck_sdio_irq to fix the SDIO stability issues on MT8516.
> > >>
> > >> Signed-off-by: Fabien Parent <fparent@baylibre.com>
> > >
> > > Maybe this is a common problem, thus I am thinking that potentially we
> > > should enable the workaround for all variants?
> > Not sure if this is of any help, but: we use the btmtksdio driver on a
> > MT8183 soc with an Android kernel based on upstream.
> >
> > With that kernel, we did not to apply this work-around in order to
> > have a stable bluetooth experience (pairing with a remote controller)
> >
> > However, on the MT8516 SoC, it's impossible for us to use btmtksdio
> > without Fabien's fix.
> >
> Yes. For mt8516 SoC,recheck_sdio_irq should be set to true for avoiding
> SDIO dat1 irq lost issue. But for mt8183 SoC, it does not need recheck
> sdio irq mechanism.

Okay, thanks for confirming.

>
> > >
> > > I have looped in Yong Mao (who invented the workaround) and Chaotian
> > > Jing, to see if they can advise us how to proceed.
> > >
> > > In any case, I think we should add a stable tag and a fixes tag.
> > >
> > > Kind regards
> > > Uffe
>
> Hi Ulf,
> Sorry. On the patch "mmc:mediatek:fix SDIO irq issue", I only consider
> fixing the issue on mt8173 SoC.But for the whole MTK upstream SoC,
> mt8183, mt2712, mt6779 and mt8192 does not need this mechanism,
> but the other upstream Soc such as mt8135, mt8173, mt2701, mt7622,
> mt8516 and mt7620 need this recheck mechanism. And all future SoC of our
> company does not need this mechanism.
> If it's convenient for you, please help me to revise it.
> Or I will submit a new patch to correct the value of setting.
> Thanks.

Please submit a new patch to enable the "recheck_sdio_irq" flag for
those variants that need it.

I would also add a fixes+stable tag and add reported-by tags from
Fabien and Mattijs.

Kind regards
Uffe

> > >
> > >> ---
> > >>  drivers/mmc/host/mtk-sd.c | 2 +-
> > >>  1 file changed, 1 insertion(+), 1 deletion(-)
> > >>
> > >> diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
> > >> index a704745e5882..3dc102eefe49 100644
> > >> --- a/drivers/mmc/host/mtk-sd.c
> > >> +++ b/drivers/mmc/host/mtk-sd.c
> > >> @@ -524,7 +524,7 @@ static const struct mtk_mmc_compatible mt7622_compat = {
> > >>
> > >>  static const struct mtk_mmc_compatible mt8516_compat = {
> > >>         .clk_div_bits = 12,
> > >> -       .recheck_sdio_irq = false,
> > >> +       .recheck_sdio_irq = true,
> > >>         .hs400_tune = false,
> > >>         .pad_tune_reg = MSDC_PAD_TUNE0,
> > >>         .async_fifo = true,
> > >> --
> > >> 2.28.0
> > >>
> > >
> > > _______________________________________________
> > > Linux-mediatek mailing list
> > > Linux-mediatek@lists.infradead.org
> > > http://lists.infradead.org/mailman/listinfo/linux-mediatek
>