drm/radeon/si: add dpm quirk for Oland

OLAND 0x1002:0x6604 0x1028:0x066F 0x00 seems to have problems
with higher sclks.

Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
diff --git a/drivers/gpu/drm/radeon/si_dpm.c b/drivers/gpu/drm/radeon/si_dpm.c
index d12b897..72e1588 100644
--- a/drivers/gpu/drm/radeon/si_dpm.c
+++ b/drivers/gpu/drm/radeon/si_dpm.c
@@ -2984,6 +2984,12 @@
 		    (rdev->pdev->device == 0x6667)) {
 			max_sclk = 75000;
 		}
+	} else if (rdev->family == CHIP_OLAND) {
+		if ((rdev->pdev->device == 0x6604) &&
+		    (rdev->pdev->subsystem_vendor == 0x1028) &&
+		    (rdev->pdev->subsystem_device == 0x066F)) {
+			max_sclk = 75000;
+		}
 	}
 
 	if (rps->vce_active) {