drm/i915/skl: Skylake moves AUX_CTL from PCH to CPU
So we can apply the old aux_ctl = dp_ctl + 0x10 rule again.
Reviewed-by: Thomas Wood <thomas.wood@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 581ba1d..17c6910 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -925,7 +925,16 @@
BUG();
}
- if (!HAS_DDI(dev))
+ /*
+ * The AUX_CTL register is usually DP_CTL + 0x10.
+ *
+ * On Haswell and Broadwell though:
+ * - Both port A DDI_BUF_CTL and DDI_AUX_CTL are on the CPU
+ * - Port B/C/D AUX channels are on the PCH, DDI_BUF_CTL on the CPU
+ *
+ * Skylake moves AUX_CTL back next to DDI_BUF_CTL, on the CPU.
+ */
+ if (!IS_HASWELL(dev) && !IS_BROADWELL(dev))
intel_dp->aux_ch_ctl_reg = intel_dp->output_reg + 0x10;
intel_dp->aux.name = name;