drm/i915: Preserve the DDI_A_4_LANES bit from the bios
Otherwise the DDI_A_4_LANES bit gets lost and we can't use > 2 lanes
on eDP. This fixes eDP on hsw with > 2 lanes.
Also s/port_reversal/saved_port_bits/ since the current name is
confusing.
Signed-off-by: Stéphane Marchesin <marcheu@chromium.org>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index 324211a..b042ee5 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -301,7 +301,7 @@
struct intel_digital_port *intel_dig_port =
enc_to_dig_port(encoder);
- intel_dp->DP = intel_dig_port->port_reversal |
+ intel_dp->DP = intel_dig_port->saved_port_bits |
DDI_BUF_CTL_ENABLE | DDI_BUF_EMP_400MV_0DB_HSW;
intel_dp->DP |= DDI_PORT_WIDTH(intel_dp->lane_count);
@@ -1109,7 +1109,8 @@
* enabling the port.
*/
I915_WRITE(DDI_BUF_CTL(port),
- intel_dig_port->port_reversal | DDI_BUF_CTL_ENABLE);
+ intel_dig_port->saved_port_bits |
+ DDI_BUF_CTL_ENABLE);
} else if (type == INTEL_OUTPUT_EDP) {
struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
@@ -1347,8 +1348,9 @@
intel_encoder->get_config = intel_ddi_get_config;
intel_dig_port->port = port;
- intel_dig_port->port_reversal = I915_READ(DDI_BUF_CTL(port)) &
- DDI_BUF_PORT_REVERSAL;
+ intel_dig_port->saved_port_bits = I915_READ(DDI_BUF_CTL(port)) &
+ (DDI_BUF_PORT_REVERSAL |
+ DDI_A_4_LANES);
intel_dig_port->dp.output_reg = DDI_BUF_CTL(port);
intel_encoder->type = INTEL_OUTPUT_UNKNOWN;