FROMLIST: drm/msm/a6xx: Retrieve gmu core range by index

Some GPUs like A612 doesn't use a named register range resource. This
is because the reg-name property is discouraged when there is just a
single resource.

To address this, retrieve the 'gmu' register range by its index. It is
always guaranteed to be at index 0.

Signed-off-by: Akhil P Oommen <[email protected]>
Reviewed-by: Dmitry Baryshkov <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: akhilpo-qcom

drivers/gpu/drm/msm/adreno/a6xx_gmu.c

@@ -1902,21 +1902,19 @@ static int cxpd_notifier_cb(struct notifier_block *nb,
 	return 0;
 }
 
-static void __iomem *a6xx_gmu_get_mmio(struct platform_device *pdev,
-		const char *name, resource_size_t *start)
+static void __iomem *a6xx_gmu_get_mmio(struct platform_device *pdev, resource_size_t *start)
 {
+	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	void __iomem *ret;
-	struct resource *res = platform_get_resource_byname(pdev,
-			IORESOURCE_MEM, name);
 
 	if (!res) {
-		DRM_DEV_ERROR(&pdev->dev, "Unable to find the %s registers\n", name);
+		DRM_DEV_ERROR(&pdev->dev, "Unable to find the gmu core registers\n");
 		return ERR_PTR(-EINVAL);
 	}
 
 	ret = ioremap(res->start, resource_size(res));
 	if (!ret) {
-		DRM_DEV_ERROR(&pdev->dev, "Unable to map the %s registers\n", name);
+		DRM_DEV_ERROR(&pdev->dev, "Unable to map the gmu core registers\n");
 		return ERR_PTR(-EINVAL);
 	}
 
@@ -1958,7 +1956,7 @@ int a6xx_gmu_wrapper_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
 	gmu->nr_clocks = ret;
 
 	/* Map the GMU registers */
-	gmu->mmio = a6xx_gmu_get_mmio(pdev, "gmu", &start);
+	gmu->mmio = a6xx_gmu_get_mmio(pdev, &start);
 	if (IS_ERR(gmu->mmio)) {
 		ret = PTR_ERR(gmu->mmio);
 		goto err_mmio;
@@ -2115,7 +2113,7 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
 		goto err_memory;
 
 	/* Map the GMU registers */
-	gmu->mmio = a6xx_gmu_get_mmio(pdev, "gmu", &start);
+	gmu->mmio = a6xx_gmu_get_mmio(pdev, &start);
 	if (IS_ERR(gmu->mmio)) {
 		ret = PTR_ERR(gmu->mmio);
 		goto err_memory;