Re: [PATCH v4 6/8] drm/mediatek: add matrix bits private data for ccorr

From: Yongqiang Niu <yongqiang.niu@mediatek.com>
To: CK Hu <ck.hu@mediatek.com>
Cc: Mark Rutland <mark.rutland@arm.com>,
	devicetree@vger.kernel.org,
	Philipp Zabel <p.zabel@pengutronix.de>,
	David Airlie <airlied@linux.ie>,
	linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
	linux-mediatek@lists.infradead.org,
	Daniel Vetter <daniel@ffwll.ch>,
	Hsin-Yi Wang <hsinyi@chromium.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v4 6/8] drm/mediatek: add matrix bits private data for ccorr
Date: Fri, 29 Jan 2021 16:59:03 +0800	[thread overview]
Message-ID: <1611910743.24406.3.camel@mhfsdcap03> (raw)
In-Reply-To: <1611909641.31184.11.camel@mtksdaap41>

On Fri, 2021-01-29 at 16:40 +0800, CK Hu wrote:
> Hi, Hsin-Yi:
> 
> On Fri, 2021-01-29 at 15:34 +0800, Hsin-Yi Wang wrote:
> > From: Yongqiang Niu <yongqiang.niu@mediatek.com>
> > 
> > matrix bits of mt8183 is 12
> > matrix bits of mt8192 is 13
> > 
> > Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
> > Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
> > ---
> >  drivers/gpu/drm/mediatek/mtk_disp_ccorr.c | 22 +++++++++++++++++++---
> >  1 file changed, 19 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c b/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c
> > index 0c68090eb1e92..1c7163a12f3b1 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c
> > @@ -31,8 +31,10 @@
> >  #define DISP_CCORR_COEF_3			0x008C
> >  #define DISP_CCORR_COEF_4			0x0090
> >  
> > +#define CCORR_MATRIX_BITS			12
> > +
> >  struct mtk_disp_ccorr_data {
> > -	u32 reserved;
> > +	u32 matrix_bits;
> >  };
> >  
> >  /**
> > @@ -116,6 +118,7 @@ void mtk_ccorr_ctm_set(struct device *dev, struct drm_crtc_state *state)
> >  	uint16_t coeffs[9] = { 0 };
> >  	int i;
> >  	struct cmdq_pkt *cmdq_pkt = NULL;
> > +	u32 matrix_bits;
> >  
> >  	if (!blob)
> >  		return;
> > @@ -123,8 +126,16 @@ void mtk_ccorr_ctm_set(struct device *dev, struct drm_crtc_state *state)
> >  	ctm = (struct drm_color_ctm *)blob->data;
> >  	input = ctm->matrix;
> >  
> > -	for (i = 0; i < ARRAY_SIZE(coeffs); i++)
> > +	if (ccorr->data)
> > +		matrix_bits = ccorr->data->matrix_bits;
> > +	else
> > +		matrix_bits = CCORR_MATRIX_BITS;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(coeffs); i++) {
> >  		coeffs[i] = mtk_ctm_s31_32_to_s1_10(input[i]);
> > +		if (matrix_bits > CCORR_MATRIX_BITS)
> > +			coeffs[i] <<= (matrix_bits - CCORR_MATRIX_BITS);
> 
> I think format of MT8192 ccorr coeffs is s1.11, after
> mtk_ctm_s31_32_to_s1_10(), you lose one bit precision. So modify
> mtk_ctm_s31_32_to_s1_10() to get maximum precision.
> 
> Regards,
> CK

mt8183 s2.10, default value 1024
mt8192 s2.11, default value 2048
> 
> > +	}
> >  
> >  	mtk_ddp_write(cmdq_pkt, coeffs[0] << 16 | coeffs[1],
> >  		      &ccorr->cmdq_reg, ccorr->regs, DISP_CCORR_COEF_0);
> > @@ -205,8 +216,13 @@ static int mtk_disp_ccorr_remove(struct platform_device *pdev)
> >  	return 0;
> >  }
> >  
> > +static const struct mtk_disp_ccorr_data mt8183_ccorr_driver_data = {
> > +	.matrix_bits = CCORR_MATRIX_BITS,
> > +};
> > +
> >  static const struct of_device_id mtk_disp_ccorr_driver_dt_match[] = {
> > -	{ .compatible = "mediatek,mt8183-disp-ccorr"},
> > +	{ .compatible = "mediatek,mt8183-disp-ccorr",
> > +	  .data = &mt8183_ccorr_driver_data},
> >  	{},
> >  };
> >  MODULE_DEVICE_TABLE(of, mtk_disp_ccorr_driver_dt_match);
> 
> 

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel