[Intel-gfx] [PATCH 03/16] drm/i915/bxt: Add a note about BXT_PORT_CL1CM_DW30 being read-only

[Imre Deak]

This register is read-only, so we have never actually set
OCL2_LDOFUSE_PWR_DIS in it as specified by the specification. Add a code
comment about this. I filed a specification update request to clarify
this there.

CC: Arthur J Runyan <arthur.j.runyan at intel.com>
Signed-off-by: Imre Deak <imre.deak at intel.com>

---

[ Art, CC'ing you in case you know if this would have an effect on
  anything. ]
---
 drivers/gpu/drm/i915/intel_ddi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index 2758622..f91306e 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -1798,6 +1798,9 @@ static void broxton_phy_init(struct drm_i915_private *dev_priv,
 	 * enabled.
 	 * TODO: port C is only connected on BXT-P, so on BXT0/1 we should
 	 * power down the second channel on PHY0 as well.
+	 *
+	 * FIXME: Clarify programming of the following, the register is
+	 * read-only with bit 6 fixed at 0 at least in stepping A.
 	 */
 	if (phy == DPIO_PHY1)
 		val |= OCL2_LDOFUSE_PWR_DIS;
-- 
2.5.0