[PATCH 22/22] drm/radeon: add support for read reg query from radeon info ioctl

[Alex Deucher]

This allows us to query certain registers from userspace
for profiling and harvest configuration.  E.g., it can
be used by the GALLIUM_HUD for profiling the status of
various gfx blocks.

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/radeon/radeon_kms.c | 8 ++++++++
 include/uapi/drm/radeon_drm.h       | 1 +
 2 files changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/radeon/radeon_kms.c b/drivers/gpu/drm/radeon/radeon_kms.c
index f15de68..86a0cb2 100644
--- a/drivers/gpu/drm/radeon/radeon_kms.c
+++ b/drivers/gpu/drm/radeon/radeon_kms.c
@@ -561,6 +561,14 @@ static int radeon_info_ioctl(struct drm_device *dev, void *data, struct drm_file
 		else
 			*value = rdev->pm.current_mclk / 100;
 		break;
+	case RADEON_INFO_READ_REG:
+		if (copy_from_user(value, value_ptr, sizeof(uint32_t))) {
+			DRM_ERROR("copy_from_user %s:%u\n", __func__, __LINE__);
+			return -EFAULT;
+		}
+		if (radeon_get_allowed_info_register(rdev, *value, value))
+			return -EINVAL;
+		break;
 	default:
 		DRM_DEBUG_KMS("Invalid request %d\n", info->request);
 		return -EINVAL;
diff --git a/include/uapi/drm/radeon_drm.h b/include/uapi/drm/radeon_drm.h
index de7ee21..871e73f 100644
--- a/include/uapi/drm/radeon_drm.h
+++ b/include/uapi/drm/radeon_drm.h
@@ -1037,6 +1037,7 @@ struct drm_radeon_cs {
 #define RADEON_INFO_CURRENT_GPU_TEMP	0x21
 #define RADEON_INFO_CURRENT_GPU_SCLK	0x22
 #define RADEON_INFO_CURRENT_GPU_MCLK	0x23
+#define RADEON_INFO_READ_REG		0x24
 
 struct drm_radeon_info {
 	uint32_t		request;
-- 
1.8.3.1