arm64: dts: imx95: Use GPU_CGC as core clock for GPU

The i.MX95 imx-sm introduced new GPU_CGC clock since imx-sm commit
ca5e078833fa ("SM-128: Add clock management via CCM LPCG direct control")
which are downstream clock of GPU clock. These new GPU_CGC clock
gate the existing GPU clock. Currently, without clk_ignore_unused
on kernel command line, those new GPU_CGC clock are unused and the
kernel will disable them. This has no impact on i.MX95 A0/A1, but
does prevent GPU register access from working at all on i.MX95 B0.
The GPU_CGC clock are present on both i.MX95 A0/A1/B0, therefore
update the DT such, that the GPU core clock are the GPU_CGC clock.
When the panthor driver enables the GPU core clock, it enables both
the GPU_CGC as well as its parent GPU clock.

Fixes: 67934f2 ("arm64: dts: imx95: Describe Mali G310 GPU")
Signed-off-by: Marek Vasut <marek.vasut@mailbox.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

Author: Marek Vasut

arch/arm64/boot/dts/freescale/imx95-clock.h

@@ -183,5 +183,6 @@
 #define IMX95_CLK_SEL_A55P                 (IMX95_CCM_NUM_CLK_SRC + 123 + 7)
 #define IMX95_CLK_SEL_DRAM                 (IMX95_CCM_NUM_CLK_SRC + 123 + 8)
 #define IMX95_CLK_SEL_TEMPSENSE            (IMX95_CCM_NUM_CLK_SRC + 123 + 9)
+#define IMX95_CLK_GPU_CGC                  (IMX95_CCM_NUM_CLK_SRC + 123 + 10)
 
 #endif	/* __CLOCK_IMX95_H */

arch/arm64/boot/dts/freescale/imx95.dtsi

@@ -2164,7 +2164,7 @@
 		gpu: gpu@4d900000 {
 			compatible = "nxp,imx95-mali", "arm,mali-valhall-csf";
 			reg = <0 0x4d900000 0 0x480000>;
-			clocks = <&scmi_clk IMX95_CLK_GPU>, <&scmi_clk IMX95_CLK_GPUAPB>;
+			clocks = <&scmi_clk IMX95_CLK_GPU_CGC>, <&scmi_clk IMX95_CLK_GPUAPB>;
 			clock-names = "core", "coregroup";
 			interrupts = <GIC_SPI 289 IRQ_TYPE_LEVEL_HIGH>,
 				     <GIC_SPI 290 IRQ_TYPE_LEVEL_HIGH>,