clk: mediatek: Add hdmi_ref HDMI PHY PLL reference clock output

The configurable hdmi_ref output of the PLL block is derived from
the tvdpll_594m clock signal via a configurable PLL post-divider.
It is used as the PLL reference input to the HDMI PHY module.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NJames Liao <jamesjj.liao@mediatek.com>
Acked-by: NStephen Boyd <sboyd@codeaurora.org>

drivers/clk/mediatek/clk-mt8173.c

@@ -1095,6 +1095,11 @@ static void __init mtk_apmixedsys_init(struct device_node *node)
 		clk_data->clks[cku->id] = clk;
 	}
 
+	clk = clk_register_divider(NULL, "hdmi_ref", "tvdpll_594m", 0,
+				   base + 0x40, 16, 3, CLK_DIVIDER_POWER_OF_TWO,
+				   NULL);
+	clk_data->clks[CLK_APMIXED_HDMI_REF] = clk;
+
 	r = of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
 	if (r)
 		pr_err("%s(): could not register clock provider: %d\n",

include/dt-bindings/clock/mt8173-clk.h

@@ -176,7 +176,8 @@
 #define CLK_APMIXED_LVDSPLL		13
 #define CLK_APMIXED_MSDCPLL2		14
 #define CLK_APMIXED_REF2USB_TX		15
-#define CLK_APMIXED_NR_CLK		16
+#define CLK_APMIXED_HDMI_REF		16
+#define CLK_APMIXED_NR_CLK		17
 
 /* INFRA_SYS */