6.12-stable review patch. If anyone has any objections, please let me know.
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From: Vasily Khoruzhick anarsoul@gmail.com
[ Upstream commit 383ca7bee8a93be9ff5a072936981c2710d2856b ]
Stop force-selecting PLL-MIPI as TCON0 parent, since it breaks video output on Pinebook that uses RGB to eDP bridge.
Partially revert commit ca1170b69968 ("clk: sunxi-ng: a64: force select PLL_MIPI in TCON0 mux"), while still leaving CLK_SET_RATE_NO_REPARENT flag set, since we do not want the clock to be reparented.
The issue is that apparently different TCON0 outputs require a different clock, or the mux might be selecting the output type.
I did an experiment: I manually configured PLL_MIPI and PLL_VIDEO0_2X to the same clock rate and flipped the switch with devmem. Experiment clearly showed that whenever PLL_MIPI is selected as TCON0 clock parent, the video output stops working.
Therefore, TCON0 clock parent corresponding to the output type must be assigned in the device tree.
Fixes: ca1170b69968 ("clk: sunxi-ng: a64: force select PLL_MIPI in TCON0 mux") Reviewed-by: Dragan Simic dsimic@manjaro.org Reviewed-by: Chen-Yu Tsai wens@csie.org Tested-by: Frank Oltmanns frank@oltmanns.dev # on PinePhone Tested-by: Stuart Gathman stuart@gathman.org # on OG Pinebook Signed-off-by: Vasily Khoruzhick anarsoul@gmail.com Link: https://patch.msgid.link/20250104074035.1611136-5-anarsoul@gmail.com Signed-off-by: Chen-Yu Tsai wens@csie.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-)
diff --git a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c index c255dba2c96db..6727a3e30a129 100644 --- a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c +++ b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c @@ -535,11 +535,11 @@ static SUNXI_CCU_M_WITH_MUX_GATE(de_clk, "de", de_parents, CLK_SET_RATE_PARENT);
/* - * DSI output seems to work only when PLL_MIPI selected. Set it and prevent - * the mux from reparenting. + * Experiments showed that RGB output requires pll-video0-2x, while DSI + * requires pll-mipi. It will not work with incorrect clock, the screen will + * be blank. + * sun50i-a64.dtsi assigns pll-mipi as TCON0 parent by default */ -#define SUN50I_A64_TCON0_CLK_REG 0x118 - static const char * const tcon0_parents[] = { "pll-mipi", "pll-video0-2x" }; static const u8 tcon0_table[] = { 0, 2, }; static SUNXI_CCU_MUX_TABLE_WITH_GATE_CLOSEST(tcon0_clk, "tcon0", tcon0_parents, @@ -959,11 +959,6 @@ static int sun50i_a64_ccu_probe(struct platform_device *pdev)
writel(0x515, reg + SUN50I_A64_PLL_MIPI_REG);
- /* Set PLL MIPI as parent for TCON0 */ - val = readl(reg + SUN50I_A64_TCON0_CLK_REG); - val &= ~GENMASK(26, 24); - writel(val | (0 << 24), reg + SUN50I_A64_TCON0_CLK_REG); - ret = devm_sunxi_ccu_probe(&pdev->dev, reg, &sun50i_a64_ccu_desc); if (ret) return ret;