On Mon, 2024-08-19 at 20:17 +0200, Mary Guillemard wrote: > > External email : Please do not click links or open attachments until > you have verified the sender or the content. > On Mon, Aug 19, 2024 at 05:38:52PM +0530, Manivannan Sadhasivam > wrote: > > On Mon, Aug 19, 2024 at 12:24:42AM +0200, Mary Guillemard wrote: > > > MT8183 supports UFSHCI 2.1 spec, but report a bogus value of 1 in > the > > > reserved part for the Legacy Single Doorbell Support (LSDBS) > capability. > > > > > > > Wow... I never thought that this quirk will be used outside of Qcom > SoCs... > > > > Yeah I found that by trial and error some weeks ago and noticed your > serie while looking to upstream this change, quite funny to see other > vendors having the same quirk here. > > > > This set UFSHCD_QUIRK_BROKEN_LSDBS_CAP when MCQ support is > explicitly > > > disabled, allowing the device to be properly registered. > > > > > > Signed-off-by: Mary Guillemard <mary@xxxxxxxxx> > > > --- > > > drivers/ufs/host/ufs-mediatek.c | 3 +++ > > > 1 file changed, 3 insertions(+) > > > > > > diff --git a/drivers/ufs/host/ufs-mediatek.c > b/drivers/ufs/host/ufs-mediatek.c > > > index 02c9064284e1..9a5919434c4e 100644 > > > --- a/drivers/ufs/host/ufs-mediatek.c > > > +++ b/drivers/ufs/host/ufs-mediatek.c > > > @@ -1026,6 +1026,9 @@ static int ufs_mtk_init(struct ufs_hba > *hba) > > > if (host->caps & UFS_MTK_CAP_DISABLE_AH8) > > > hba->caps |= UFSHCD_CAP_HIBERN8_WITH_CLK_GATING; > > > > > > +if (host->caps & UFS_MTK_CAP_DISABLE_MCQ) > > > > How can this be the deciding factor? You said above that the issue > is with > > MT8183 SoC. So why not just use the quirk only for that platform? > > > > - Mani > > > > So my current assumption is that it also affect other Mediatek SoCs > that are also based on UFS 2.1 spec but I cannot check this. > > Instead, we know that if MCQ isn't supported, we must fallback to > LSDB > as there is no other ways to drive the device. > > UFS_MTK_CAP_DISABLE_MCQ (mediatek,ufs-disable-mcq) being unused > upstream, > I think that's an acceptable fix. > > Another way to handle this would be to add a new dt property and add > it > to ufs_mtk_host_caps but I feel that my approach should be enough. > Hi Mary, Yes, the MT8395 indeed requires the LSDBS flag, but not every MediaTek legacy chip does. So setting the LSDBS flag here is appropriate. Thanks. Peter > > > +hba->quirks |= UFSHCD_QUIRK_BROKEN_LSDBS_CAP; > > > + > > > ufs_mtk_init_clocks(hba); > > > > > > /* > > > -- > > > 2.46.0 > > > > > > > > > > -- > > மணிவண்ணன் சதாசிவம் > > - Mary >
