drm/panfrost: Set DMA masks earlier

The DMA masks need to be set correctly before any DMA API activity kicks
off, and the current point in panfrost_probe() is way too late in that
regard. since panfrost_mmu_init() has already set up a live address
space and DMA-mapped MMU pagetables. We can't set masks until we've
queried the appropriate value from MMU_FEATURES, but as soon as
reasonably possible after that should suffice.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/64361b929a5c61d2ab9580262ecb3d369164cfcb.1556195258.git.robin.murphy@arm.com

drivers/gpu/drm/panfrost/panfrost_drv.c

@@ -3,8 +3,6 @@
 /* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
 /* Copyright 2019 Collabora ltd. */
 
-#include <linux/bitfield.h>
-#include <linux/dma-mapping.h>
 #include <linux/module.h>
 #include <linux/of_platform.h>
 #include <linux/pagemap.h>
@@ -401,9 +399,6 @@ static int panfrost_probe(struct platform_device *pdev)
 		goto err_out0;
 	}
 
-	dma_set_mask_and_coherent(pfdev->dev,
-		DMA_BIT_MASK(FIELD_GET(0xff00, pfdev->features.mmu_features)));
-
 	err = panfrost_devfreq_init(pfdev);
 	if (err) {
 		dev_err(&pdev->dev, "Fatal error during devfreq init\n");

drivers/gpu/drm/panfrost/panfrost_gpu.c

@@ -2,8 +2,10 @@
 /* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
 /* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
 /* Copyright 2019 Collabora ltd. */
+#include <linux/bitfield.h>
 #include <linux/bitmap.h>
 #include <linux/delay.h>
+#include <linux/dma-mapping.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
@@ -332,6 +334,9 @@ int panfrost_gpu_init(struct panfrost_device *pfdev)
 
 	panfrost_gpu_init_features(pfdev);
 
+	dma_set_mask_and_coherent(pfdev->dev,
+		DMA_BIT_MASK(FIELD_GET(0xff00, pfdev->features.mmu_features)));
+
 	irq = platform_get_irq_byname(to_platform_device(pfdev->dev), "gpu");
 	if (irq <= 0)
 		return -ENODEV;