[PATCH 3/5] drm/panfrost: add support for reset quirk

[Neil Armstrong]

The T820, G31 & G52 GPUs integratewd by Amlogic in the respective GXM, G12A/SM1 & G12B
SoCs needs a quirk in the PWR registers at the GPU reset time.

This adds a callback in the device compatible struct of permit this.

Signed-off-by: Neil Armstrong <narmstrong at baylibre.com>
---
 drivers/gpu/drm/panfrost/panfrost_device.h | 3 +++
 drivers/gpu/drm/panfrost/panfrost_gpu.c    | 4 ++++
 2 files changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h
index 2cf1a6a13af8..4c9cd5452ba5 100644
--- a/drivers/gpu/drm/panfrost/panfrost_device.h
+++ b/drivers/gpu/drm/panfrost/panfrost_device.h
@@ -73,6 +73,9 @@ struct panfrost_compatible {
 
 	/* IOMMU quirks flags */
 	unsigned long pgtbl_quirks;
+
+	/* Vendor implementation quirks at reset time callback */
+	void (*vendor_reset_quirk)(struct panfrost_device *pfdev);
 };
 
 struct panfrost_device {
diff --git a/drivers/gpu/drm/panfrost/panfrost_gpu.c b/drivers/gpu/drm/panfrost/panfrost_gpu.c
index e0f190e43813..c129aaf77790 100644
--- a/drivers/gpu/drm/panfrost/panfrost_gpu.c
+++ b/drivers/gpu/drm/panfrost/panfrost_gpu.c
@@ -62,6 +62,10 @@ int panfrost_gpu_soft_reset(struct panfrost_device *pfdev)
 	gpu_write(pfdev, GPU_INT_CLEAR, GPU_IRQ_RESET_COMPLETED);
 	gpu_write(pfdev, GPU_CMD, GPU_CMD_SOFT_RESET);
 
+	/* The Amlogic GPU integration needs quirks at this stage */
+	if (pfdev->comp->vendor_reset_quirk)
+		pfdev->comp->vendor_reset_quirk(pfdev);
+
 	ret = readl_relaxed_poll_timeout(pfdev->iomem + GPU_INT_RAWSTAT,
 		val, val & GPU_IRQ_RESET_COMPLETED, 100, 10000);
 
-- 
2.22.0