| Message ID | 1459515767-29228-4-git-send-email-imre.deak@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Apr 01, 2016 at 04:02:34PM +0300, Imre Deak wrote: > 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. Hmm. Interesting. It's r/w on my CHV, and the PHY spec agrees. Of course I can't really tell whether it has any effect on the x1 PHY. If I set it on the x2 PHY it definitely makes the channel unusable. > > CC: Arthur J Runyan <arthur.j.runyan@intel.com> > Signed-off-by: Imre Deak <imre.deak@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 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
On pe, 2016-04-08 at 21:02 +0300, Ville Syrjälä wrote: > On Fri, Apr 01, 2016 at 04:02:34PM +0300, Imre Deak wrote: > > 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. > > Hmm. Interesting. It's r/w on my CHV, and the PHY spec agrees. Of > course > I can't really tell whether it has any effect on the x1 PHY. If I set > it > on the x2 PHY it definitely makes the channel unusable. Note that meanwhile the corresponding BSpec change request got updated to "Confirmed"/"Won't be fixed". > > CC: Arthur J Runyan <arthur.j.runyan@intel.com> > > Signed-off-by: Imre Deak <imre.deak@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 > > > > _______________________________________________ > > Intel-gfx mailing list > > Intel-gfx@lists.freedesktop.org > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx >
On pe, 2016-04-08 at 21:12 +0300, Imre Deak wrote: > On pe, 2016-04-08 at 21:02 +0300, Ville Syrjälä wrote: > > On Fri, Apr 01, 2016 at 04:02:34PM +0300, Imre Deak wrote: > > > 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. > > > > Hmm. Interesting. It's r/w on my CHV, and the PHY spec agrees. Of > > course > > I can't really tell whether it has any effect on the x1 PHY. If I > > set > > it > > on the x2 PHY it definitely makes the channel unusable. > > Note that meanwhile the corresponding BSpec change request got > updated > to "Confirmed"/"Won't be fixed". Sorry, it's just "Confirmed". > > > CC: Arthur J Runyan <arthur.j.runyan@intel.com> > > > Signed-off-by: Imre Deak <imre.deak@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;
On Fri, Apr 01, 2016 at 04:02:34PM +0300, Imre Deak wrote: > 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@intel.com> > Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: David Weinehall <david.weinehall@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 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
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;
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@intel.com> Signed-off-by: Imre Deak <imre.deak@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(+)