3 files changed, 6 insertions, 1 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
index d5680a0c87af..275b26a708d6 100644
--- a/drivers/gpu/drm/radeon/radeon_drv.c
+++ b/drivers/gpu/drm/radeon/radeon_drv.c
@@ -48,7 +48,7 @@
  * - 2.5.0 - add get accel 2 to work around ddx breakage for evergreen
  * - 2.6.0 - add tiling config query (r6xx+), add initial HiZ support (r300->r500)
  *   2.7.0 - fixups for r600 2D tiling support. (no external ABI change), add eg dyn gpr regs
- *   2.8.0 - pageflip support, r500 US_FORMAT regs. r500 ARGB2101010 colorbuf, r300->r500 CMASK
+ *   2.8.0 - pageflip support, r500 US_FORMAT regs. r500 ARGB2101010 colorbuf, r300->r500 CMASK, clock crystal query
  */
 #define KMS_DRIVER_MAJOR        2
 #define KMS_DRIVER_MINOR        8
diff --git a/drivers/gpu/drm/radeon/radeon_kms.c b/drivers/gpu/drm/radeon/radeon_kms.c
index 28a53e4a925f..98321298cffd 100644
--- a/drivers/gpu/drm/radeon/radeon_kms.c
+++ b/drivers/gpu/drm/radeon/radeon_kms.c
@@ -201,6 +201,10 @@ int radeon_info_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
                 }
                 radeon_set_filp_rights(dev, &rdev->cmask_filp, filp, &value);
                 break;
+        case RADEON_INFO_CLOCK_CRYSTAL_FREQ:
+                /* return clock value in KHz */
+                value = rdev->clock.spll.reference_freq * 10;
+                break;
         default:
                 DRM_DEBUG_KMS("Invalid request %d\n", info->request);
                 return -EINVAL;
diff --git a/include/drm/radeon_drm.h b/include/drm/radeon_drm.h
index e95a86b8b689..e5c607a02d57 100644
--- a/include/drm/radeon_drm.h
+++ b/include/drm/radeon_drm.h
@@ -907,6 +907,7 @@ struct drm_radeon_cs {
 #define RADEON_INFO_TILING_CONFIG       0x06
 #define RADEON_INFO_WANT_HYPERZ         0x07
 #define RADEON_INFO_WANT_CMASK          0x08 /* get access to CMASK on r300 */
+#define RADEON_INFO_CLOCK_CRYSTAL_FREQ  0x09 /* clock crystal frequency */
 
 struct drm_radeon_info {
         uint32_t                request;