drm/i915: Preserve the FDI line reversal override bit on CPT
The FDI link has supported link reversal to make the PCB layout
engineer's life easier for quite a while and we have always presered
this bit as we programmed FDI_RX_CTL with a read/modify/write sequence.
We're trying to take a bit more control over what the BIOS leaves in
various register and with the introduction of DDI, started to program
FDI_RX_CTL fully.
There's a fused bit to indicate DMI link reversal and FDI defaults to
mirroring that configuration. We have a bit to override that behaviour
that we need to preserve from the BIOS.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
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/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index d7542cd..64919ee 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3911,7 +3911,7 @@
#define FDI_10BPC (1<<16)
#define FDI_6BPC (2<<16)
#define FDI_12BPC (3<<16)
-#define FDI_LINK_REVERSE_OVERWRITE (1<<15)
+#define FDI_RX_LINK_REVERSAL_OVERRIDE (1<<15)
#define FDI_DMI_LINK_REVERSE_MASK (1<<14)
#define FDI_RX_PLL_ENABLE (1<<13)
#define FDI_FS_ERR_CORRECT_ENABLE (1<<11)