Re: [EXT] Re: [PATCH v2 04/15] drm/mxsfb: Reset vital register for a proper initialization

[Robert Chiras <robert.chiras@nxp.com>]

Hi Stefan,

On Mi, 2019-08-14 at 13:11 +0200, Stefan Agner wrote:
> On 2019-08-14 12:48, Robert Chiras wrote:
> > 
> > Some of the regiters need, like LCDC_CTRL and
> > CTRL2_OUTSTANDING_REQS
> Typo in registers, and there is a need to many.
Thanks, will fix this.
> 
> > 
> > needs to be properly cleared and initialized for a better start and
> > stop
> > routine.
> 
> 
> > 
> > 
> > Signed-off-by: Robert Chiras <robert.chiras@nxp.com>
> > ---
> >  drivers/gpu/drm/mxsfb/mxsfb_crtc.c | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
> > b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
> > index b69ace8..5e44f57 100644
> > --- a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
> > +++ b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
> > @@ -127,6 +127,10 @@ static void mxsfb_enable_controller(struct
> > mxsfb_drm_private *mxsfb)
> >               clk_prepare_enable(mxsfb->clk_disp_axi);
> >       clk_prepare_enable(mxsfb->clk);
> > 
> > +     if (mxsfb->devdata->ipversion >= 4)
> > +             writel(CTRL2_OUTSTANDING_REQS(REQ_16),
> > +                    mxsfb->base + LCDC_V4_CTRL2 + REG_SET);
> > +
> >       /* If it was disabled, re-enable the mode again */
> >       writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_SET);
> > 
> > @@ -136,12 +140,19 @@ static void mxsfb_enable_controller(struct
> > mxsfb_drm_private *mxsfb)
> >       writel(reg, mxsfb->base + LCDC_VDCTRL4);
> > 
> >       writel(CTRL_RUN, mxsfb->base + LCDC_CTRL + REG_SET);
> > +     writel(CTRL1_RECOVERY_ON_UNDERFLOW, mxsfb->base + LCDC_CTRL1
> > + REG_SET);
> This seems not to be accounted for in the commit message. Can you do
> this in a separate commit?
> 
> Also I suggest to introduce CTRL1_RECOVERY_ON_UNDERFLOW in that same
> commit.
You are right, I missed this one in the description. I will add this
one too.
> 
> --
> Stefan
> 
> > 
> >  }
> > 
> >  static void mxsfb_disable_controller(struct mxsfb_drm_private
> > *mxsfb)
> >  {
> >       u32 reg;
> > 
> > +     if (mxsfb->devdata->ipversion >= 4)
> > +             writel(CTRL2_OUTSTANDING_REQS(0x7),
> > +                    mxsfb->base + LCDC_V4_CTRL2 + REG_CLR);
> > +
> > +     writel(CTRL_RUN, mxsfb->base + LCDC_CTRL + REG_CLR);
> > +
> >       /*
> >        * Even if we disable the controller here, it will still
> > continue
> >        * until its FIFOs are running out of data
> > @@ -295,6 +306,7 @@ void mxsfb_crtc_enable(struct mxsfb_drm_private
> > *mxsfb)
> >       dma_addr_t paddr;
> > 
> >       mxsfb_enable_axi_clk(mxsfb);
> > +     writel(0, mxsfb->base + LCDC_CTRL);
> >       mxsfb_crtc_mode_set_nofb(mxsfb);
> > 
> >       /* Write cur_buf as well to avoid an initial corrupt frame */

Thanks,
Robert