[PATCH RESEND v6 08/11] drm/mediatek: gamma: Support multi-bank gamma LUT

AngeloGioacchino Del Regno
2023-07-27T09:48:06Z

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>
---
drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 74 ++++++++++++++---------
1 file changed, 47 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index 407fb0264b80..f1a0b18b6c1a 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -25,6 +25,8 @@
#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)
@@ -38,6 +40,7 @@
struct mtk_disp_gamma_data {
bool has_dither;
bool lut_diff;
+ u16 lut_bank_size;
u16 lut_size;
u8 lut_bits;
};
@@ -84,9 +87,10 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crt
struct drm_color_lut *lut;
void __iomem *lut_base;
bool lut_diff;
- u16 lut_size;
+ u16 lut_bank_size, lut_size;
u8 lut_bits;
- u32 cfg_val, word;
+ 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)
@@ -94,43 +98,57 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crt

if (gamma && gamma->data) {
lut_diff = gamma->data->lut_diff;
+ lut_bank_size = gamma->data->lut_bank_size;
lut_bits = gamma->data->lut_bits;
lut_size = gamma->data->lut_size;
} else {
lut_diff = false;
+ lut_bank_size = LUT_SIZE_DEFAULT;
lut_bits = LUT_BITS_DEFAULT;
lut_size = LUT_SIZE_DEFAULT;
}
+ num_lut_banks = lut_size / lut_bank_size;

cfg_val = readl(regs + DISP_GAMMA_CFG);
lut_base = regs + DISP_GAMMA_LUT;
lut = (struct drm_color_lut *)state->gamma_lut->data;
- for (i = 0; i < lut_size; i++) {
- struct drm_color_lut diff, hwlut;
-
- hwlut.red = drm_color_lut_extract(lut[i].red, lut_bits);
- hwlut.green = drm_color_lut_extract(lut[i].green, lut_bits);
- hwlut.blue = drm_color_lut_extract(lut[i].blue, lut_bits);
-
- if (!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);
- } else {
- diff.red = lut[i].red - lut[i - 1].red;
- diff.red = drm_color_lut_extract(diff.red, lut_bits);
-
- diff.green = lut[i].green - lut[i - 1].green;
- diff.green = drm_color_lut_extract(diff.green, lut_bits);
-
- diff.blue = lut[i].blue - lut[i - 1].blue;
- diff.blue = drm_color_lut_extract(diff.blue, 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);
+
+ 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);
+ writel(lbank_val, regs + DISP_GAMMA_BANK);
+ }
+
+ for (i = 0; i < lut_bank_size; i++) {
+ int n = (cur_bank * lut_bank_size) + i;
+ struct drm_color_lut diff, hwlut;
+
+ hwlut.red = drm_color_lut_extract(lut[n].red, lut_bits);
+ hwlut.green = drm_color_lut_extract(lut[n].green, lut_bits);
+ hwlut.blue = drm_color_lut_extract(lut[n].blue, lut_bits);
+
+ if (!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);
+ } else {
+ diff.red = lut[n].red - lut[n - 1].red;
+ diff.red = drm_color_lut_extract(diff.red, lut_bits);
+
+ diff.green = lut[n].green - lut[n - 1].green;
+ diff.green = drm_color_lut_extract(diff.green, lut_bits);
+
+ diff.blue = lut[n].blue - lut[n - 1].blue;
+ diff.blue = drm_color_lut_extract(diff.blue, 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);
+ }
+ writel(word, (lut_base + i * 4));
}
- writel(word, (lut_base + i * 4));
}

/* Enable the gamma table */
@@ -241,11 +259,13 @@ 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_bank_size = 512,
.lut_bits = 10,
.lut_size = 512,
};

static const struct mtk_disp_gamma_data mt8183_gamma_driver_data = {
+ .lut_bank_size = 512,
.lut_bits = 10,
.lut_diff = true,
.lut_size = 512,
--
2.40.1