Reapply "drm/nouveau/firmware: Fix SG_DEBUG error with nvkm_firmware_…

…ctor()"

This commit fixes a kernel BUG (which ends up resulting in a hang) on a Lenovo
ThinkBook 14 G4+ ARA with AMD + NVIDIA graphics.

This reverts commit a222a64.

Signed-off-by: Mingcong Bai <baimingcong@uniontech.com>
Signed-off-by: WangYuli <wangyuli@uniontech.com>

drivers/gpu/drm/nouveau/nvkm/core/firmware.c

@@ -205,7 +205,9 @@ nvkm_firmware_dtor(struct nvkm_firmware *fw)
 		break;
 	case NVKM_FIRMWARE_IMG_DMA:
 		nvkm_memory_unref(&memory);
-		dma_free_coherent(fw->device->dev, sg_dma_len(&fw->mem.sgl), fw->img, fw->phys);
+		dma_unmap_single(fw->device->dev, fw->phys, sg_dma_len(&fw->mem.sgl),
+				 DMA_TO_DEVICE);
+		kfree(fw->img);
 		break;
 	case NVKM_FIRMWARE_IMG_SGT:
 		nvkm_memory_unref(&memory);
@@ -235,14 +237,17 @@ nvkm_firmware_ctor(const struct nvkm_firmware_func *func, const char *name,
 		fw->img = kmemdup(src, fw->len, GFP_KERNEL);
 		break;
 	case NVKM_FIRMWARE_IMG_DMA: {
-		dma_addr_t addr;
-
 		len = ALIGN(fw->len, PAGE_SIZE);
 
-		fw->img = dma_alloc_coherent(fw->device->dev, len, &addr, GFP_KERNEL);
-		if (fw->img) {
-			memcpy(fw->img, src, fw->len);
-			fw->phys = addr;
+		fw->img = kmalloc(len, GFP_KERNEL);
+		if (!fw->img)
+			return -ENOMEM;
+
+		memcpy(fw->img, src, fw->len);
+		fw->phys = dma_map_single(fw->device->dev, fw->img, len, DMA_TO_DEVICE);
+		if (dma_mapping_error(fw->device->dev, fw->phys)) {
+			kfree(fw->img);
+			return -EFAULT;
 		}
 
 		sg_init_one(&fw->mem.sgl, fw->img, len);