[PATCH v1 2/2] imx: mach: imx8: fdt: support newer GPU0 bus node name

[Stefan Eichenberger <eichest@gmail.com>]

From: Stefan Eichenberger <stefan.eichenberger@toradex.com>

Mainline Linux and NXP downstream kernels starting with 6.18 name the
GPU0 subsystem bus@53000000, while older downstream kernels used
bus@53100000. Because of that, the industrial GPU clock rates were not
applied and GPU0 kept running at the default 700/850 MHz instead of
the 625 MHz limit of the industrial SoC.

Use /bus@53000000/gpu@53100000 and, if it does not exist, fall back to
the legacy /bus@53100000/gpu@53100000.

Signed-off-by: Stefan Eichenberger <stefan.eichenberger@toradex.com>
---
 arch/arm/mach-imx/imx8/fdt.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-imx/imx8/fdt.c b/arch/arm/mach-imx/imx8/fdt.c
index 630b5e55702..05d2ddead91 100644
--- a/arch/arm/mach-imx/imx8/fdt.c
+++ b/arch/arm/mach-imx/imx8/fdt.c
@@ -317,9 +317,14 @@ static void update_fdt_gpu_industrial_frequencies(void *blob)
 	gpu_assigned_clocks[0] = cpu_to_fdt32(625000000); /* Core Clock */
 	gpu_assigned_clocks[1] = cpu_to_fdt32(625000000); /* Shader Clock */
 
-	err = change_property(blob, "/bus@53100000/gpu@53100000",
+	err = change_property(blob, "/bus@53000000/gpu@53100000",
 			      "assigned-clock-rates", gpu_assigned_clocks,
 			      sizeof(gpu_assigned_clocks));
+	/* NXP kernels before 6.18 use bus@53100000 */
+	if (err == -FDT_ERR_NOTFOUND)
+		err = change_property(blob, "/bus@53100000/gpu@53100000",
+				      "assigned-clock-rates", gpu_assigned_clocks,
+				      sizeof(gpu_assigned_clocks));
 	if (err && err != -FDT_ERR_NOTFOUND)
 		printf("Failed to set assigned-clock-rates for GPU0: %s\n",
 		       fdt_strerror(err));
-- 
2.56.0