Hi, Jason:
On Mon, 2022-09-12 at 09:30 +0800, Jason-JH.Lin wrote:
> Add lut_bits in gamma driver data for each SoC and adjust the usage
> of lut_bits in mtk_drm_gamma_set_common().
>
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 36 ++++++++++++++++-----
> --
> 1 file changed, 25 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> index 0a1022032b71..be82d15a5204 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> @@ -25,11 +25,14 @@
>
> #define LUT_10BIT_MASK 0x03ff
> #define LUT_SIZE_DEFAULT 512 /* for setting
> gamma lut from AAL */
> +#define LUT_BITS_DEFAULT 10
> +#define LUT_INPUT_BITS 16 /* input lut
> bit from application */
I think we should use drm_color_lut_extract() to let the input bits
transparent. So add one patch to use drm_color_lut_extract(), and then
apply this patch.
Regards,
CK
>
> struct mtk_disp_gamma_data {
> bool has_dither;
> bool lut_diff;
> u16 lut_size;
> + u8 lut_bits;
> };
>
> /*
> @@ -72,17 +75,23 @@ void mtk_gamma_set_common(struct device *dev,
> void __iomem *regs, struct drm_crt
> struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
> bool lut_diff = false;
> u16 lut_size = LUT_SIZE_DEFAULT;
> + u8 lut_bits = LUT_BITS_DEFAULT;
> + u8 shift_bits;
> unsigned int i, reg;
> struct drm_color_lut *lut;
> void __iomem *lut_base;
> - u32 word;
> + u32 word, mask;
> u32 diff[3] = {0};
>
> if (gamma && gamma->data) {
> lut_diff = gamma->data->lut_diff;
> lut_size = gamma->data->lut_size;
> + lut_bits = gamma->data->lut_bits;
> }
>
> + shift_bits = LUT_INPUT_BITS - lut_bits;
> + mask = GENMASK(lut_bits - 1, 0);
> +
> if (state->gamma_lut) {
> reg = readl(regs + DISP_GAMMA_CFG);
> reg = reg | GAMMA_LUT_EN;
> @@ -92,17 +101,20 @@ void mtk_gamma_set_common(struct device *dev,
> void __iomem *regs, struct drm_crt
> for (i = 0; i < lut_size; i++) {
>
> if (!lut_diff || (i % 2 == 0)) {
> - word = (((lut[i].red >> 6) &
> LUT_10BIT_MASK) << 20) +
> - (((lut[i].green >> 6) &
> LUT_10BIT_MASK) << 10) +
> - ((lut[i].blue >> 6) &
> LUT_10BIT_MASK);
> + word = (((lut[i].red >> shift_bits) &
> mask) << 20) +
> + (((lut[i].green >> shift_bits)
> & mask) << 10) +
> + ((lut[i].blue >> shift_bits) &
> mask);
> } else {
> - diff[0] = (lut[i].red >> 6) - (lut[i -
> 1].red >> 6);
> - diff[1] = (lut[i].green >> 6) - (lut[i
> - 1].green >> 6);
> - diff[2] = (lut[i].blue >> 6) - (lut[i -
> 1].blue >> 6);
> -
> - word = ((diff[0] & LUT_10BIT_MASK) <<
> 20) +
> - ((diff[1] & LUT_10BIT_MASK) <<
> 10) +
> - (diff[2] & LUT_10BIT_MASK);
> + diff[0] = (lut[i].red >> shift_bits) -
> + (lut[i - 1].red >>
> shift_bits);
> + diff[1] = (lut[i].green >> shift_bits)
> -
> + (lut[i - 1].green >>
> shift_bits);
> + diff[2] = (lut[i].blue >> shift_bits) -
> + (lut[i - 1].blue >>
> shift_bits);
> +
> + word = ((diff[0] & mask) << 20) +
> + ((diff[1] & mask) << 10) +
> + (diff[2] & mask);
> }
> writel(word, (lut_base + i * 4));
> }
> @@ -209,11 +221,13 @@ static int mtk_disp_gamma_remove(struct
> platform_device *pdev)
> static const struct mtk_disp_gamma_data mt8173_gamma_driver_data = {
> .has_dither = true,
> .lut_size = 512,
> + .lut_bits = 10,
> };
>
> static const struct mtk_disp_gamma_data mt8183_gamma_driver_data = {
> .lut_diff = true,
> .lut_size = 512,
> + .lut_bits = 10,
> };
>
> static const struct of_device_id mtk_disp_gamma_driver_dt_match[] =
> {
