From de7f29a1fe1dc2864d8a47f8c39d508442cae167 Mon Sep 17 00:00:00 2001 From: AngeloGioacchino Del Regno Date: Fri, 11 Sep 2026 09:40:14 +0200 Subject: phy: mediatek: phy-mtk-hdmi-mt8195: Fix PLL calc divisor overflow When trying to calculate a PLL rate for target display resolutions above 2560x1440, 24bpp, 30Hz, the pixel clock value will be more than 32-bits long but the division to finally calculate the digital clock divider is being done with div_u64(), which expects a 32bit unsigned divisor. Fix the overflow by using div64_u64() instead. Fixes: 9d9ff3d2a4a5 ("phy: mediatek: hdmi: mt8195: fix wrong pll calculus") Reviewed-by: Manivannan Sadhasivam Signed-off-by: AngeloGioacchino Del Regno Link: https://patch.msgid.link/20260911074015.9994-2-angelogioacchino.delregno@collabora.com Signed-off-by: Vinod Koul --- drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/phy/mediatek') diff --git a/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c b/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c index 1426a2db9..e6ee8e080 100644 --- a/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c +++ b/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c @@ -290,7 +290,7 @@ static int mtk_hdmi_pll_calc(struct mtk_hdmi_phy *hdmi_phy, struct clk_hw *hw, posdiv2 = 1; /* Digital clk divider, max /32 */ - digital_div = div_u64(ns_hdmipll_ck, posdiv1 * posdiv2 * pixel_clk); + digital_div = div64_u64(ns_hdmipll_ck, posdiv1 * posdiv2 * pixel_clk); if (!(digital_div <= 32 && digital_div >= 1)) return -EINVAL; -- cgit v1.3.1 From 486a70ef848264dcf9a57f0bb0452848db9537de Mon Sep 17 00:00:00 2001 From: AngeloGioacchino Del Regno Date: Fri, 11 Sep 2026 09:40:15 +0200 Subject: phy: mediatek: phy-mtk-hdmi-mt8195: Fix TMDS clk bit ratio setting The comment in the mtk_phy_tmds_clk_ratio() function clearly and correctly explains that the TMDS ratio has to be 1/10 for data rates under 3.4Gbps, and 1/40 over that. Unfortunately though, the TXC_DIV register setting was wrong, as in value 3 means to divide by 8 and, in order to achieve the in spec 1/40 (tmds) data rate, this has to divide by 4 instead! Add definitions for the TXC_DIV register values clearly explaining the meanings (DIV2, DIV4, DIV8), and program the correct, DIV 4, value to the register in mtk_phy_tmds_clk_ratio(). This fixes out of spec clocking and, with this change, SoCs using the MT8195 class HDMI PHYs can now successfully be configured to output 3840x2160@60Hz over HDMI. Fixes: 45810d486bb4 ("phy: mediatek: add support for phy-mtk-hdmi-mt8195") Reviewed-by: Manivannan Sadhasivam Signed-off-by: AngeloGioacchino Del Regno Link: https://patch.msgid.link/20260911074015.9994-3-angelogioacchino.delregno@collabora.com Signed-off-by: Vinod Koul --- drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c | 2 +- drivers/phy/mediatek/phy-mtk-hdmi-mt8195.h | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) (limited to 'drivers/phy/mediatek') diff --git a/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c b/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c index e6ee8e080..a4bc12689 100644 --- a/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c +++ b/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.c @@ -36,7 +36,7 @@ mtk_phy_tmds_clk_ratio(struct mtk_hdmi_phy *hdmi_phy, bool enable) * clock bit ratio 1:40, under 3.4Gbps, clock bit ratio 1:10 */ if (enable) - mtk_phy_update_field(regs + HDMI20_CLK_CFG, REG_TXC_DIV, 3); + mtk_phy_update_field(regs + HDMI20_CLK_CFG, REG_TXC_DIV, VAL_TXC_DIV4); else mtk_phy_clear_bits(regs + HDMI20_CLK_CFG, REG_TXC_DIV); } diff --git a/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.h b/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.h index e26caaf4d..58800d765 100644 --- a/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.h +++ b/drivers/phy/mediatek/phy-mtk-hdmi-mt8195.h @@ -17,6 +17,9 @@ #define HDMI20_CLK_CFG 0x70 #define REG_TXC_DIV GENMASK(31, 30) +#define VAL_TXC_DIV2 1 +#define VAL_TXC_DIV4 2 +#define VAL_TXC_DIV8 3 #define HDMI_1_CFG_0 0x00 #define RG_HDMITX21_DRV_IBIAS_CLK GENMASK(10, 5) -- cgit v1.3.1