Re: [PATCH v3] vsp1: fix video output on R8A77970

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Sergei,

On Thursday, 22 February 2018 18:26:20 EET Laurent Pinchart wrote:
> On Thursday, 18 January 2018 16:05:51 EET Sergei Shtylyov wrote:
> > Commit d455b45f8393 ("v4l: vsp1: Add support for new VSP2-BS, VSP2-DL,
> > and VSP2-D instances") added support for the VSP2-D found in the R-Car
> > V3M (R8A77970) but the video output that VSP2-D sends to DU has a greenish
> > garbage-like line repeated every 8 screen rows. It turns out that R-Car
> > V3M has the LIF0 buffer attribute register that you need to set to a non-
> > default value in order to get rid of the output artifacts...
> > 
> > Based on the original (and large) patch by Daisuke Matsushita
> > <daisuke.matsushita.ns@hitachi.com>.
> > 
> > Fixes: d455b45f8393 ("v4l: vsp1: Add support for new VSP2-BS, VSP2-DL and
> > VSP2-D instances") Signed-off-by: Sergei Shtylyov
> > <sergei.shtylyov@cogentembedded.com>
> > 
> > ---
> > This patch is against the 'media_tree.git' repo's 'fixes' branch.
> > 
> > Changes in version 3:
> > - reworded the comment in lif_configure();
> > - reworded the patch description.
> > 
> > Changes in version 2:
> > - added a  comment before the V3M SoC check;
> > - fixed indetation in that check;
> > - reformatted  the patch description.
> > 
> >  drivers/media/platform/vsp1/vsp1_lif.c  |   15 +++++++++++++++
> >  drivers/media/platform/vsp1/vsp1_regs.h |    5 +++++
> >  2 files changed, 20 insertions(+)
> > 
> > Index: media_tree/drivers/media/platform/vsp1/vsp1_lif.c
> > ===================================================================
> > --- media_tree.orig/drivers/media/platform/vsp1/vsp1_lif.c
> > +++ media_tree/drivers/media/platform/vsp1/vsp1_lif.c
> > @@ -155,6 +155,21 @@ static void lif_configure(struct vsp1_en
> > 
> >  			(obth << VI6_LIF_CTRL_OBTH_SHIFT) |
> >  			(format->code == 0 ? VI6_LIF_CTRL_CFMT : 0) |
> >  			VI6_LIF_CTRL_REQSEL | VI6_LIF_CTRL_LIF_EN);
> > 
> > +
> > +	/*
> > +	 * On R-Car V3M the LIF0 buffer attribute register has to be set
> > +	 * to a non-default value to guarantee proper operation (otherwise
> > +	 * artifacts may appear on the output). The value required by
> > +	 * the manual is not explained but is likely a buffer size or
> > +	 * threshold...
> 
> One period is enough :-)
> 
> > +	 */
> > +	if ((entity->vsp1->version &
> > +	     (VI6_IP_VERSION_MODEL_MASK | VI6_IP_VERSION_SOC_MASK)) ==
> > +	    (VI6_IP_VERSION_MODEL_VSPD_V3 | VI6_IP_VERSION_SOC_V3M)) {
> > +		vsp1_lif_write(lif, dl, VI6_LIF_LBA,
> > +			       VI6_LIF_LBA_LBA0 |
> > +			       (1536 << VI6_LIF_LBA_LBA1_SHIFT));
> > +	}
> 
> There's no need for braces or inner parentheses.

There's of course a need for the inner parentheses, please ignore this 
comment.

> To make this easier to read I propose defining a new macro
> VI6_IP_VERSION_MASK that combines both the model and SoC. Otherwise this
> looks good to me,
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> 
> I'll post a v4 with that change in reply to this e-mail, please let me know
> if you're fine with it.
> 
> >  }
> >  
> >  static const struct vsp1_entity_operations lif_entity_ops = {
> > 
> > Index: media_tree/drivers/media/platform/vsp1/vsp1_regs.h
> > ===================================================================
> > --- media_tree.orig/drivers/media/platform/vsp1/vsp1_regs.h
> > +++ media_tree/drivers/media/platform/vsp1/vsp1_regs.h
> > @@ -693,6 +693,11 @@
> >  #define VI6_LIF_CSBTH_LBTH_MASK		(0x7ff << 0)
> >  #define VI6_LIF_CSBTH_LBTH_SHIFT	0
> > 
> > +#define VI6_LIF_LBA			0x3b0c
> > +#define VI6_LIF_LBA_LBA0		(1 << 31)
> > +#define VI6_LIF_LBA_LBA1_MASK		(0xfff << 16)
> > +#define VI6_LIF_LBA_LBA1_SHIFT		16
> > +
> >  /* ----------------------------------------------------------------------
> >   * Security Control Registers
> >   */

-- 
Regards,

Laurent Pinchart