Re: [PATCH v8 08/13] drm/mediatek: gamma: Support multi-bank gamma LUT

["CK Hu (胡俊光)" <ck.hu@mediatek.com>]

Hi, Angelo:

On Wed, 2023-08-02 at 10:30 +0200, AngeloGioacchino Del Regno wrote:
> Il 02/08/23 06:12, CK Hu (胡俊光) ha scritto:
> > Hi, Angelo:
> > 
> > On Tue, 2023-08-01 at 13:58 +0200, AngeloGioacchino Del Regno
> > wrote:
> > > Newer Gamma IP have got multiple LUT banks: support specifying
> > > the
> > > size of the LUT banks and handle bank-switching before
> > > programming
> > > the LUT in mtk_gamma_set_common() in preparation for adding
> > > support
> > > for MT8195 and newer SoCs.
> > > 
> > > Suggested-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> > > [Angelo: Refactored original commit]
> > > Signed-off-by: AngeloGioacchino Del Regno <
> > > angelogioacchino.delregno@collabora.com>
> > > Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
> > > ---
> > >   drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 73 +++++++++++++++-
> > > ---
> > > ----
> > >   1 file changed, 47 insertions(+), 26 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > > b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > > index a6f7af1a9e8e..fb7c3650a9f7 100644
> > > --- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > > +++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > > @@ -24,6 +24,8 @@
> > >   #define DISP_GAMMA_SIZE				0x0030
> > >   #define DISP_GAMMA_SIZE_HSIZE				GENMASK
> > > (28, 16)
> > >   #define DISP_GAMMA_SIZE_VSIZE				GENMASK
> > > (12, 0)
> > > +#define DISP_GAMMA_BANK				0x0100
> > > +#define DISP_GAMMA_BANK_BANK				GENMASK
> > > (1, 0)
> > >   #define DISP_GAMMA_LUT				0x0700
> > >   
> > >   #define DISP_GAMMA_LUT_10BIT_R			GENMASK(29, 20)
> > > @@ -32,10 +34,12 @@
> > >   
> > >   #define LUT_10BIT_MASK				0x03ff
> > >   #define LUT_BITS_DEFAULT			10
> > > +#define LUT_BANK_SIZE_DEFAULT			512
> > >   
> > >   struct mtk_disp_gamma_data {
> > >   	bool has_dither;
> > >   	bool lut_diff;
> > > +	u16 lut_bank_size;
> > >   	u16 lut_size;
> > >   	u8 lut_bits;
> > >   };
> > > @@ -80,7 +84,9 @@ void mtk_gamma_set_common(struct device *dev,
> > > void
> > > __iomem *regs,
> > >   	void __iomem *lut_base;
> > >   	bool lut_diff;
> > >   	u8 lut_bits;
> > > -	u32 cfg_val, word;
> > > +	u16 lut_bank_size;
> > > +	u32 cfg_val, lbank_val, word;
> > > +	int cur_bank, num_lut_banks;
> > >   
> > >   	/* If there's no gamma lut there's nothing to do here.
> > > */
> > >   	if (!state->gamma_lut)
> > > @@ -91,41 +97,54 @@ void mtk_gamma_set_common(struct device *dev,
> > > void __iomem *regs,
> > >   
> > >   	if (gamma && gamma->data) {
> > >   		lut_diff = gamma->data->lut_diff;
> > > +		lut_bank_size = gamma->data->lut_bank_size;
> > >   		lut_bits = gamma->data->lut_bits;
> > >   	} else {
> > >   		lut_diff = false;
> > > +		lut_bank_size = LUT_BANK_SIZE_DEFAULT;
> > 
> > LUT_BANK_SIZE_DEFAULT is only for AAL driver, so place it in AAL
> > driver
> > and pass it into this function.
> > 
> 
> I completely dislike having a function taking too many parameters.
> 
> Since mtk_gamma_set() in DISP_GAMMA will anyway expand in the future
> to
> support newer hardware, I'm thinking about just removing AAL support
> from
> this function and duplicate the few (15 or something) lines of code
> in
> mtk_disp_aal instead, so that we stop commonizing the mtk_gamma_set
> for
> both DISP_AAL and DISP_GAMMA.
> 
> Any opinions on that?

OK, let's stop commonizing the mtk_gamma_set
().

Regards,
CK

> 
> Regards,
> Angelo
> 
> > Regards,
> > CK
> > 
> 
>