[PATCH v11 10/16] drm/mediatek: gamma: Add support for 12-bit LUT
AngeloGioacchino Del Regno
angelogioacchino.delregno at collabora.com
Thu Oct 12 02:57:30 PDT 2023
New SoCs, like MT8195, not only may support bigger lookup tables, but
have got a different register layout to support bigger precision:
support specifying the number of `lut_bits` for each SoC and use it
in mtk_gamma_set_common() to perform the right calculations and add
support for 12-bit gamma lookup tables.
While at it, also reorder the variables in mtk_gamma_set_common()
and rename `lut_base` to `lut0_base` to improve readability.
Reviewed-by: Jason-JH.Lin <jason-jh.lin at mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat at baylibre.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno at collabora.com>
---
drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 83 +++++++++++++++++------
1 file changed, 64 insertions(+), 19 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index 911468984ad5..6305cd95e6d4 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -26,17 +26,26 @@
#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)
+
struct mtk_disp_gamma_data {
bool has_dither;
bool lut_diff;
u16 lut_bank_size;
u16 lut_size;
+ u8 lut_bits;
};
/*
@@ -72,28 +81,48 @@ unsigned int mtk_gamma_get_lut_size(struct device *dev)
return 0;
}
+/*
+ * 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];
+ u8 lut_bits = gamma->data->lut_bits;
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)
return;
num_lut_banks = gamma->data->lut_size / gamma->data->lut_bank_size;
- 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, !!(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);
}
@@ -101,29 +130,43 @@ void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
int n = cur_bank * gamma->data->lut_bank_size + i;
struct drm_color_lut diff, hwlut;
- hwlut.red = drm_color_lut_extract(lut[n].red, 10);
- hwlut.green = drm_color_lut_extract(lut[n].green, 10);
- hwlut.blue = drm_color_lut_extract(lut[n].blue, 10);
+ 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 (!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 (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, 10);
+ 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, 10);
+ 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, 10);
-
- 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);
+ diff.blue = drm_color_lut_extract(diff.blue, lut_bits);
+
+ if (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 (lut_bits == 12)
+ writel(word[1], lut1_base + i * 4);
}
}
@@ -225,11 +268,13 @@ static void 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,
};
--
2.42.0
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