drm/radeon: check if pcie gen 2 is already enabled (v2)

If so, skip enabling it to save time.

v2: coding style fixes
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/evergreen.c

@@ -3431,9 +3431,14 @@ void evergreen_pcie_gen2_enable(struct radeon_device *rdev)
 	if (!(mask & DRM_PCIE_SPEED_50))
 		return;
 
+	speed_cntl = RREG32_PCIE_P(PCIE_LC_SPEED_CNTL);
+	if (speed_cntl & LC_CURRENT_DATA_RATE) {
+		DRM_INFO("PCIE gen 2 link speeds already enabled\n");
+		return;
+	}
+
 	DRM_INFO("enabling PCIE gen 2 link speeds, disable with radeon.pcie_gen2=0\n");
 
-	speed_cntl = RREG32_PCIE_P(PCIE_LC_SPEED_CNTL);
 	if ((speed_cntl & LC_OTHER_SIDE_EVER_SENT_GEN2) ||
 	    (speed_cntl & LC_OTHER_SIDE_SUPPORTS_GEN2)) {
 

drivers/gpu/drm/radeon/r600.c

@@ -3703,6 +3703,12 @@ static void r600_pcie_gen2_enable(struct radeon_device *rdev)
 	if (!(mask & DRM_PCIE_SPEED_50))
 		return;
 
+	speed_cntl = RREG32_PCIE_P(PCIE_LC_SPEED_CNTL);
+	if (speed_cntl & LC_CURRENT_DATA_RATE) {
+		DRM_INFO("PCIE gen 2 link speeds already enabled\n");
+		return;
+	}
+
 	DRM_INFO("enabling PCIE gen 2 link speeds, disable with radeon.pcie_gen2=0\n");
 
 	/* 55 nm r6xx asics */