[PATCH 1/6] clk: imx8mp: add 700 MHz rate entry for VIDEO_PLL1

Johannes Schneider johannes.schneider at leica-geosystems.com
Mon Jun 1 21:09:47 PDT 2026


From: Thomas Haemmerle <thomas.haemmerle at leica-geosystems.com>

The LVDS serializer requires link_freq = pixel_clock × 7.  For a 25 MHz
pixel clock the link frequency is 175 MHz.  VIDEO_PLL1 must be set to
700 MHz so the divider chain (VIDEO_PLL1 / 4 = 175 MHz) produces an
exact match; without it clk_set_rate() rounds down to 650 MHz, yielding
only 162.5 MHz and causing the LVDS transmitter to output ~743 pixels
per line instead of 800 — visible as a black strip on the right edge.

PLL parameters: Fin=24 MHz, P=3, S=2, K=0 → 24 × 350 / (3 × 4) = 700 MHz.

Assisted-by: Claude:claude-sonnet-4-6
Signed-of-by: Thomas Haemmerle <thomas.haemmerle at leica-geosystems.com>
---
 drivers/clk/imx/clk-pll14xx.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/clk/imx/clk-pll14xx.c b/drivers/clk/imx/clk-pll14xx.c
index 6716a6f555..db7e744e87 100644
--- a/drivers/clk/imx/clk-pll14xx.c
+++ b/drivers/clk/imx/clk-pll14xx.c
@@ -61,6 +61,7 @@ static const struct imx_pll14xx_rate_table imx_pll1416x_tbl[] = {
 };
 
 static const struct imx_pll14xx_rate_table imx_pll1443x_tbl[] = {
+	PLL_1443X_RATE(700000000U, 350, 3, 2, 0),
 	PLL_1443X_RATE(650000000U, 325, 3, 2, 0),
 	PLL_1443X_RATE(594000000U, 198, 2, 2, 0),
 	PLL_1443X_RATE(393216000U, 262, 2, 3, 9437),

base-commit: 81fbe2e8d0d445032498a0bfecf9fd270f00985a
-- 
2.43.0




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