[PATCH v10 11/16] drm/mediatek: gamma: Add support for 12-bit LUT and MT8195
AngeloGioacchino Del Regno
angelogioacchino.delregno at collabora.com
Thu Sep 14 03:32:57 PDT 2023
Il 15/08/23 09:57, Chen-Yu Tsai ha scritto:
> On Fri, Aug 4, 2023 at 3:29 PM AngeloGioacchino Del Regno
> <angelogioacchino.delregno at collabora.com> wrote:
>>
>> Add support for 12-bit gamma lookup tables and introduce the first
>> user for it: MT8195.
>> While at it, also reorder the variables in mtk_gamma_set_common()
>> and rename `lut_base` to `lut0_base` to improve readability.
>>
>> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno at collabora.com>
>> Reviewed-by: Jason-JH.Lin <jason-jh.lin at mediatek.com>
>> Reviewed-by: Alexandre Mergnat <amergnat at baylibre.com>
>> ---
>> drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 74 +++++++++++++++++++----
>> 1 file changed, 62 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
>> index 3f1c6815ea5a..7d2f8042ace0 100644
>> --- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
>> +++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
>> @@ -26,12 +26,20 @@
>> #define DISP_GAMMA_SIZE_VSIZE GENMASK(12, 0)
>> #define DISP_GAMMA_BANK 0x0100
>> #define DISP_GAMMA_BANK_BANK GENMASK(1, 0)
>> +#define DISP_GAMMA_BANK_DATA_MODE BIT(2)
>> #define DISP_GAMMA_LUT 0x0700
>> +#define DISP_GAMMA_LUT1 0x0b00
>>
>> +/* For 10 bit LUT layout, R/G/B are in the same register */
>> #define DISP_GAMMA_LUT_10BIT_R GENMASK(29, 20)
>> #define DISP_GAMMA_LUT_10BIT_G GENMASK(19, 10)
>> #define DISP_GAMMA_LUT_10BIT_B GENMASK(9, 0)
>>
>> +/* For 12 bit LUT layout, R/G are in LUT, B is in LUT1 */
>> +#define DISP_GAMMA_LUT_12BIT_R GENMASK(11, 0)
>> +#define DISP_GAMMA_LUT_12BIT_G GENMASK(23, 12)
>> +#define DISP_GAMMA_LUT_12BIT_B GENMASK(11, 0)
>> +
>> #define LUT_10BIT_MASK 0x03ff
>> #define LUT_BITS_DEFAULT 10
>> #define LUT_SIZE_DEFAULT 512
>> @@ -77,14 +85,30 @@ unsigned int mtk_gamma_get_lut_size(struct device *dev)
>> return LUT_SIZE_DEFAULT;
>> }
>>
>> +/*
>> + * SoCs supporting 12-bits LUTs are using a new register layout that does
>> + * always support (by HW) both 12-bits and 10-bits LUT but, on those, we
>> + * ignore the support for 10-bits in this driver and always use 12-bits.
>> + *
>> + * Summarizing:
>> + * - SoC HW support 9/10-bits LUT only
>> + * - Old register layout
>> + * - 10-bits LUT supported
>> + * - 9-bits LUT not supported
>> + * - SoC HW support both 10/12bits LUT
>> + * - New register layout
>> + * - 12-bits LUT supported
>> + * - 10-its LUT not supported
>> + */
>> void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
>> {
>> struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
>> - unsigned int i;
>> - struct drm_color_lut *lut;
>> - void __iomem *lut_base;
>> - u32 cfg_val, lbank_val, word;
>> + void __iomem *lut0_base = gamma->regs + DISP_GAMMA_LUT;
>> + void __iomem *lut1_base = gamma->regs + DISP_GAMMA_LUT1;
>> + u32 cfg_val, data_mode, lbank_val, word[2];
>> int cur_bank, num_lut_banks;
>> + struct drm_color_lut *lut;
>> + unsigned int i;
>>
>> /* If there's no gamma lut there's nothing to do here. */
>> if (!state->gamma_lut)
>> @@ -92,14 +116,17 @@ void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
>>
>> num_lut_banks = gamma->data->lut_size / gamma->data->lut_bank_size;
>> cfg_val = readl(gamma->regs + DISP_GAMMA_CFG);
>> - lut_base = gamma->regs + DISP_GAMMA_LUT;
>> lut = (struct drm_color_lut *)state->gamma_lut->data;
>>
>> + /* Switch to 12 bits data mode if supported */
>> + data_mode = FIELD_PREP(DISP_GAMMA_BANK_DATA_MODE, !!(gamma->data->lut_bits == 12));
>> +
>> for (cur_bank = 0; cur_bank < num_lut_banks; cur_bank++) {
>>
>> /* Switch gamma bank and set data mode before writing LUT */
>> if (num_lut_banks > 1) {
>> lbank_val = FIELD_PREP(DISP_GAMMA_BANK_BANK, cur_bank);
>> + lbank_val |= data_mode;
>> writel(lbank_val, gamma->regs + DISP_GAMMA_BANK);
>> }
>>
>> @@ -112,9 +139,15 @@ void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
>> hwlut.blue = drm_color_lut_extract(lut[n].blue, gamma->data->lut_bits);
>>
>> if (!gamma->data->lut_diff || (i % 2 == 0)) {
>> - word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
>> - word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, hwlut.green);
>> - word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
>> + if (gamma->data->lut_bits == 12) {
>> + word[0] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_R, hwlut.red);
>> + word[0] |= FIELD_PREP(DISP_GAMMA_LUT_12BIT_G, hwlut.green);
>> + word[1] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_B, hwlut.blue);
>> + } else {
>> + word[0] = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
>> + word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, hwlut.green);
>> + word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
>> + }
>> } else {
>> diff.red = lut[n].red - lut[n - 1].red;
>> diff.red = drm_color_lut_extract(diff.red, gamma->data->lut_bits);
>> @@ -125,11 +158,19 @@ void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
>> diff.blue = lut[n].blue - lut[n - 1].blue;
>> diff.blue = drm_color_lut_extract(diff.blue, gamma->data->lut_bits);
>>
>> - word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
>> - word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
>> - word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, diff.blue);
>> + if (gamma->data->lut_bits == 12) {
>> + word[0] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_R, diff.red);
>> + word[0] |= FIELD_PREP(DISP_GAMMA_LUT_12BIT_G, diff.green);
>> + word[1] = FIELD_PREP(DISP_GAMMA_LUT_12BIT_B, diff.blue);
>> + } else {
>> + word[0] = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
>> + word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
>> + word[0] |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, diff.blue);
>> + }
>> }
>> - writel(word, (lut_base + i * 4));
>> + writel(word[0], (lut0_base + i * 4));
>> + if (gamma->data->lut_bits == 12)
>> + writel(word[1], (lut1_base + i * 4));
>> }
>> }
>>
>> @@ -246,11 +287,20 @@ static const struct mtk_disp_gamma_data mt8183_gamma_driver_data = {
>> .lut_size = 512,
>> };
>>
>> +static const struct mtk_disp_gamma_data mt8195_gamma_driver_data = {
>> + .lut_bank_size = 256,
>> + .lut_bits = 12,
>> + .lut_diff = true,
>> + .lut_size = 1024,
>> +};
>> +
>> static const struct of_device_id mtk_disp_gamma_driver_dt_match[] = {
>> { .compatible = "mediatek,mt8173-disp-gamma",
>> .data = &mt8173_gamma_driver_data},
>> { .compatible = "mediatek,mt8183-disp-gamma",
>> .data = &mt8183_gamma_driver_data},
>> + { .compatible = "mediatek,mt8195-disp-gamma",
>> + .data = &mt8195_gamma_driver_data},
>
> I assume we need matching changes for the DT binding and to the DT?
>
Sorry for the late reply; no, we don't need any bindings/dt changes for this,
as the bindings are matching the current devicetree node in mt8195.dtsi, and
the node has
compatible = "mediatek,mt8195-disp-gamma", "mediatek,mt8183-disp-gamma";
so, no devicetree and/or bindings modification is needed.
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/arch/arm64/boot/dts/mediatek/mt8195.dtsi?h=next-20230914#n2724
Regards,
Angelo
> ChenYu
>
>> {},
>> };
>> MODULE_DEVICE_TABLE(of, mtk_disp_gamma_driver_dt_match);
>> --
>> 2.41.0
>>
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