Re: [PATCH] omapfb: dss: Fix max fclk divider for omap36xx

[Tomi Valkeinen]

Hi,

On 03/07/2020 22:36, Sam Ravnborg wrote:
> Hi Tomi.
>
> On Fri, Jul 03, 2020 at 10:17:29AM +0300, Tomi Valkeinen wrote:
> > On 30/06/2020 21:26, Adam Ford wrote:
> > > The drm/omap driver was fixed to correct an issue where using a
> > > divider of 32 breaks the DSS despite the TRM stating 32 is a valid
> > > number.  Through experimentation, it appears that 31 works, and
> > > it is consistent with the value used by the drm/omap driver.
> > >
> > > This patch fixes the divider for fbdev driver instead of the drm.
> > >
> > > Fixes: f76ee892a99e ("omapfb: copy omapdss & displays for omapfb")
> > >
> > > Cc: <stable@xxxxxxxxxxxxxxx> #4.9+
> > > Signed-off-by: Adam Ford <aford173@xxxxxxxxx>
> > > ---
> > > Linux 4.4 will need a similar patch, but it doesn't apply cleanly.
> > >
> > > The DRM version of this same fix is:
> > > e2c4ed148cf3 ("drm/omap: fix max fclk divider for omap36xx")
> > >
> > >
> > > diff --git a/drivers/video/fbdev/omap2/omapfb/dss/dss.c b/drivers/video/fbdev/omap2/omapfb/dss/dss.c
> > > index 7252d22dd117..bfc5c4c5a26a 100644
> > > --- a/drivers/video/fbdev/omap2/omapfb/dss/dss.c
> > > +++ b/drivers/video/fbdev/omap2/omapfb/dss/dss.c
> > > @@ -833,7 +833,7 @@ static const struct dss_features omap34xx_dss_feats = {
> > >    };
> > >    static const struct dss_features omap3630_dss_feats = {
> > > -	.fck_div_max		=	32,
> > > +	.fck_div_max		=	31,
> > >    	.dss_fck_multiplier	=	1,
> > >    	.parent_clk_name	=	"dpll4_ck",
> > >    	.dpi_select_source	=	&dss_dpi_select_source_omap2_omap3,
> >
> > Reviewed-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
> Will you apply to drm-misc?

This is for fbdev, so I presume Bartlomiej will pick this one.

> Note  following output from "dim fixes":
> $ dim fixes f76ee892a99e
> Fixes: f76ee892a99e ("omapfb: copy omapdss & displays for omapfb")
> Cc: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
> Cc: Dave Airlie <airlied@xxxxxxxxx>
> Cc: Rob Clark <robdclark@xxxxxxxxx>
> Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Cc: Sam Ravnborg <sam@xxxxxxxxxxxx>
> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
> Cc: Jason Yan <yanaijie@xxxxxxxxxx>
> Cc: "Andrew F. Davis" <afd@xxxxxx>
> Cc: YueHaibing <yuehaibing@xxxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx> # v4.5+
>
> Here it says the fix is valid from v4.5 onwards.

Hmm... Adam, you marked the fix to apply to v4.9+, and then you said 
v4.4 needs a new patch (that's before the big copy/rename). Did you 
check the versions between 4.4 and 4.9? I would guess this one applies 
to v4.5+.

 Tomi

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