[Intel-gfx] [PATCH] drm/i915: HDCP: fix Ri prime check done during link check

[Oliver Barta]

On Tue, Mar 3, 2020 at 10:33 AM Ramalingam C <ramalingam.c at intel.com> wrote:
>
> On 2020-02-29 at 11:39:22 +0100, Oliver Barta wrote:
> > From: Oliver Barta <oliver.barta at aptiv.com>
> >
> > The check was always succeeding even in case of a mismatch due to the
> > HDCP_STATUS_ENC bit being set. Make sure both bits are actually set.
> >
> > Signed-off-by: Oliver Barta <oliver.barta at aptiv.com>
> Looks good to me. But we need to do same on intel_hdcp_auth(), where we
> check the R0 on authentication.
>
> -Ram
Thanks for review and your suggestion. I have created a separate patch as
the problem is a little bit different in intel_hdcp_auth(). See
https://patchwork.freedesktop.org/series/74271/

Oliver
> > Fixes: 2320175feb74 ("drm/i915: Implement HDCP for HDMI")
> > ---
> >  Submitted before as part of patch series
> >  https://patchwork.freedesktop.org/series/73961/
> >  For some reason the versioning got messed up.
> >  I marked the patch series as superseded and I'm
> >  starting all over. Sorry for spamming you.
> >
> >  drivers/gpu/drm/i915/display/intel_hdmi.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_hdmi.c b/drivers/gpu/drm/i915/display/intel_hdmi.c
> > index 0ac9bdfbc094..ac4276157182 100644
> > --- a/drivers/gpu/drm/i915/display/intel_hdmi.c
> > +++ b/drivers/gpu/drm/i915/display/intel_hdmi.c
> > @@ -1536,7 +1536,8 @@ bool intel_hdmi_hdcp_check_link(struct intel_digital_port *intel_dig_port)
> >       intel_de_write(i915, HDCP_RPRIME(i915, cpu_transcoder, port), ri.reg);
> >
> >       /* Wait for Ri prime match */
> > -     if (wait_for(intel_de_read(i915, HDCP_STATUS(i915, cpu_transcoder, port)) &
> > +     if (wait_for((intel_de_read(i915, HDCP_STATUS(i915, cpu_transcoder,
> > +                  port)) & (HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC)) ==
> >                    (HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC), 1)) {
> >               DRM_ERROR("Ri' mismatch detected, link check failed (%x)\n",
> >                         intel_de_read(i915, HDCP_STATUS(i915, cpu_transcoder, port)));
> > --
> > 2.20.1
> >