ARM: dts: qcom: apq8064: Use 27MHz PXO clock as DSI PLL reference

[ Upstream commit f1db21c315 ]

The 28NM DSI PLL driver for msm8960 calculates with a 27MHz reference
clock and should hence use PXO, not CXO which runs at 19.2MHz.

Note that none of the DSI PHY/PLL drivers currently use this "ref"
clock; they all rely on (sometimes inexistant) global clock names and
usually function normally without a parent clock.  This discrepancy will
be corrected in a future patch, for which this change needs to be in
place first.

Fixes: 6969d1d9c6 ("ARM: dts: qcom-apq8064: Set 'cxo_board' as ref clock of the DSI PHY")
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Link: https://lore.kernel.org/r/20210829203027.276143-2-marijn.suijten@somainline.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

arch/arm/boot/dts/qcom-apq8064.dtsi

@@ -198,7 +198,7 @@
 			clock-frequency = <19200000>;
 		};
 
-		pxo_board {
+		pxo_board: pxo_board {
 			compatible = "fixed-clock";
 			#clock-cells = <0>;
 			clock-frequency = <27000000>;
@@ -1305,7 +1305,7 @@
 			reg-names = "dsi_pll", "dsi_phy", "dsi_phy_regulator";
 			clock-names = "iface_clk", "ref";
 			clocks = <&mmcc DSI_M_AHB_CLK>,
-				 <&cxo_board>;
+				 <&pxo_board>;
 		};