From: Imre Deak Date: Fri, 1 Apr 2016 13:02:34 +0000 (+0300) Subject: drm/i915/bxt: Add a note about BXT_PORT_CL1CM_DW30 being read-only X-Git-Tag: v4.7-rc1~77^2~37^2~64 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=28ca6931f07f83a397e10493a798c1f00c415c40;p=linux.git drm/i915/bxt: Add a note about BXT_PORT_CL1CM_DW30 being read-only 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 Signed-off-by: Imre Deak Reviewed-by: David Weinehall Link: http://patchwork.freedesktop.org/patch/msgid/1459515767-29228-4-git-send-email-imre.deak@intel.com --- diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c index 921edf183d22..2b9e79d59c13 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;