[PATCH v2 1/3] drm/rockchip: dsi: Add maximum per lane bit rate calculation

Chaoyi Chen kernel at airkyi.com
Tue Jun 2 20:35:30 PDT 2026


From: Chaoyi Chen <chaoyi.chen at rock-chips.com>

Different chips have varying support for the maximum bit rate per lane.

Add calculation for the maximum per lane bit rate for various chip
platforms.

Signed-off-by: Chaoyi Chen <chaoyi.chen at rock-chips.com>
---
Changes in v2:
- Fix the unit conversion for max_mbps.
- Split the lane rate calculation into a separate patch.

---
 drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
index 3547d91b25d3..1060abec9f29 100644
--- a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
+++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
@@ -268,6 +268,7 @@ struct rockchip_dw_dsi_chip_data {
 
 	unsigned int flags;
 	unsigned int max_data_lanes;
+	unsigned long max_bit_rate_per_lane;
 };
 
 struct dw_mipi_dsi_rockchip {
@@ -565,7 +566,7 @@ dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
 	int bpp;
 	unsigned long mpclk, tmp;
 	unsigned int target_mbps = 1000;
-	unsigned int max_mbps = dppa_map[ARRAY_SIZE(dppa_map) - 1].max_mbps;
+	unsigned int max_mbps;
 	unsigned long best_freq = 0;
 	unsigned long fvco_min, fvco_max, fin, fout;
 	unsigned int min_prediv, max_prediv;
@@ -573,6 +574,7 @@ dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
 	unsigned long _fbdiv, best_fbdiv;
 	unsigned long min_delta = ULONG_MAX;
 
+	max_mbps = dsi->cdata->max_bit_rate_per_lane / USEC_PER_SEC;
 	dsi->format = format;
 	bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
 	if (bpp < 0) {
@@ -1503,6 +1505,7 @@ static const struct rockchip_dw_dsi_chip_data px30_chip_data[] = {
 						PX30_DSI_FORCETXSTOPMODE), 0),
 
 		.max_data_lanes = 4,
+		.max_bit_rate_per_lane = 1000000000UL,
 	},
 	{ /* sentinel */ }
 };
@@ -1515,6 +1518,7 @@ static const struct rockchip_dw_dsi_chip_data rk3128_chip_data[] = {
 						RK3128_DSI_FORCERXMODE |
 						RK3128_DSI_FORCETXSTOPMODE), 0),
 		.max_data_lanes = 4,
+		.max_bit_rate_per_lane = 1000000000UL,
 	},
 	{ /* sentinel */ }
 };
@@ -1527,6 +1531,7 @@ static const struct rockchip_dw_dsi_chip_data rk3288_chip_data[] = {
 		.lcdsel_lit = FIELD_PREP_WM16_CONST(RK3288_DSI0_LCDC_SEL, 1),
 
 		.max_data_lanes = 4,
+		.max_bit_rate_per_lane = 1500000000UL,
 	},
 	{
 		.reg = 0xff964000,
@@ -1535,6 +1540,7 @@ static const struct rockchip_dw_dsi_chip_data rk3288_chip_data[] = {
 		.lcdsel_lit = FIELD_PREP_WM16_CONST(RK3288_DSI1_LCDC_SEL, 1),
 
 		.max_data_lanes = 4,
+		.max_bit_rate_per_lane = 1500000000UL,
 	},
 	{ /* sentinel */ }
 };
@@ -1547,6 +1553,7 @@ static const struct rockchip_dw_dsi_chip_data rk3368_chip_data[] = {
 						RK3368_DSI_FORCETXSTOPMODE |
 						RK3368_DSI_FORCERXMODE), 0),
 		.max_data_lanes = 4,
+		.max_bit_rate_per_lane = 1500000000UL,
 	},
 	{ /* sentinel */ }
 };
@@ -1634,6 +1641,7 @@ static const struct rockchip_dw_dsi_chip_data rk3399_chip_data[] = {
 
 		.flags = DW_MIPI_NEEDS_PHY_CFG_CLK | DW_MIPI_NEEDS_GRF_CLK,
 		.max_data_lanes = 4,
+		.max_bit_rate_per_lane = 1500000000UL,
 	},
 	{
 		.reg = 0xff968000,
@@ -1658,6 +1666,7 @@ static const struct rockchip_dw_dsi_chip_data rk3399_chip_data[] = {
 
 		.flags = DW_MIPI_NEEDS_PHY_CFG_CLK | DW_MIPI_NEEDS_GRF_CLK,
 		.max_data_lanes = 4,
+		.max_bit_rate_per_lane = 1500000000UL,
 
 		.dphy_rx_init = rk3399_dphy_tx1rx1_init,
 		.dphy_rx_power_on = rk3399_dphy_tx1rx1_power_on,
@@ -1674,6 +1683,7 @@ static const struct rockchip_dw_dsi_chip_data rk3506_chip_data[] = {
 			     FIELD_PREP_WM16_CONST(RK3506_DSI_FORCERXMODE, 0) |
 			     FIELD_PREP_WM16_CONST(RK3506_DSI_FORCETXSTOPMODE, 0)),
 		.max_data_lanes = 2,
+		.max_bit_rate_per_lane = 1500000000UL,
 	},
 	{ /* sentinel */ }
 };
@@ -1687,6 +1697,7 @@ static const struct rockchip_dw_dsi_chip_data rk3568_chip_data[] = {
 			     FIELD_PREP_WM16_CONST(RK3568_DSI0_TURNDISABLE, 0) |
 			     FIELD_PREP_WM16_CONST(RK3568_DSI0_FORCERXMODE, 0)),
 		.max_data_lanes = 4,
+		.max_bit_rate_per_lane = 1200000000UL,
 	},
 	{
 		.reg = 0xfe070000,
@@ -1696,6 +1707,7 @@ static const struct rockchip_dw_dsi_chip_data rk3568_chip_data[] = {
 			     FIELD_PREP_WM16_CONST(RK3568_DSI1_TURNDISABLE, 0) |
 			     FIELD_PREP_WM16_CONST(RK3568_DSI1_FORCERXMODE, 0)),
 		.max_data_lanes = 4,
+		.max_bit_rate_per_lane = 1200000000UL,
 	},
 	{ /* sentinel */ }
 };
@@ -1708,6 +1720,7 @@ static const struct rockchip_dw_dsi_chip_data rv1126_chip_data[] = {
 			     FIELD_PREP_WM16_CONST(RV1126_DSI_FORCERXMODE, 0) |
 			     FIELD_PREP_WM16_CONST(RV1126_DSI_FORCETXSTOPMODE, 0)),
 		.max_data_lanes = 4,
+		.max_bit_rate_per_lane = 1000000000UL,
 	},
 	{ /* sentinel */ }
 };
-- 
2.53.0




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