[PATCH 3/3] drm/radeon: try to enable pcie gen2 where possible.

[Dave Airlie <airlied@gmail.com>]

From: Dave Airlie <airlied@redhat.com>

This attempts to enable PCIE gen2 where possible, disabling
via radeon.pcie_gen2 in case of regression, so we can test it.

Signed-off-by: Dave Airlie <airlied@redhat.com>
---
 drivers/gpu/drm/radeon/evergreen.c  |    5 +++++
 drivers/gpu/drm/radeon/r600.c       |    5 +++++
 drivers/gpu/drm/radeon/radeon_drv.c |    4 ++--
 drivers/gpu/drm/radeon/rv770.c      |    5 +++++
 4 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index f716e08..3a422a3 100644
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -3295,6 +3295,11 @@ void evergreen_pcie_gen2_enable(struct radeon_device *rdev)
 	if (ASIC_IS_X2(rdev))
 		return;
 
+	if (radeon_pcie_gen2 == -1 && drm_pcie_is_5gt_link_speed_capable(rdev->ddev) != 0)
+		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)) {
diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index 43d0c41..d7b62dc 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -3683,6 +3683,11 @@ static void r600_pcie_gen2_enable(struct radeon_device *rdev)
 	if (rdev->family <= CHIP_R600)
 		return;
 
+	if (radeon_pcie_gen2 == -1 && drm_pcie_is_5gt_link_speed_capable(rdev->ddev) != 0)
+		return;
+
+	DRM_INFO("enabling PCIE gen 2 link speeds (disable with radeon.pcie_gen2=0\n");
+
 	/* 55 nm r6xx asics */
 	if ((rdev->family == CHIP_RV670) ||
 	    (rdev->family == CHIP_RV620) ||
diff --git a/drivers/gpu/drm/radeon/radeon_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
index 2c4d53f..042fcff 100644
--- a/drivers/gpu/drm/radeon/radeon_drv.c
+++ b/drivers/gpu/drm/radeon/radeon_drv.c
@@ -133,7 +133,7 @@ int radeon_tv = 1;
 int radeon_audio = 0;
 int radeon_disp_priority = 0;
 int radeon_hw_i2c = 0;
-int radeon_pcie_gen2 = 0;
+int radeon_pcie_gen2 = -1;
 int radeon_msi = -1;
 int radeon_lockup_timeout = 10000;
 
@@ -179,7 +179,7 @@ module_param_named(disp_priority, radeon_disp_priority, int, 0444);
 MODULE_PARM_DESC(hw_i2c, "hw i2c engine enable (0 = disable)");
 module_param_named(hw_i2c, radeon_hw_i2c, int, 0444);
 
-MODULE_PARM_DESC(pcie_gen2, "PCIE Gen2 mode (1 = enable)");
+MODULE_PARM_DESC(pcie_gen2, "PCIE Gen2 mode (-1 = auto, 0 = disable, 1 = enable)");
 module_param_named(pcie_gen2, radeon_pcie_gen2, int, 0444);
 
 MODULE_PARM_DESC(msi, "MSI support (1 = enable, 0 = disable, -1 = auto)");
diff --git a/drivers/gpu/drm/radeon/rv770.c b/drivers/gpu/drm/radeon/rv770.c
index b4f51c5..965745c 100644
--- a/drivers/gpu/drm/radeon/rv770.c
+++ b/drivers/gpu/drm/radeon/rv770.c
@@ -1135,6 +1135,11 @@ static void rv770_pcie_gen2_enable(struct radeon_device *rdev)
 	if (ASIC_IS_X2(rdev))
 		return;
 
+	if (radeon_pcie_gen2 == -1 && drm_pcie_is_5gt_link_speed_capable(rdev->ddev) != 0)
+		return;
+
+	DRM_INFO("enabling PCIE gen 2 link speeds (disable with radeon.pcie_gen2=0\n");
+
 	/* advertise upconfig capability */
 	link_width_cntl = RREG32_PCIE_P(PCIE_LC_LINK_WIDTH_CNTL);
 	link_width_cntl &= ~LC_UPCONFIGURE_DIS;
-- 
1.7.7.6