> -----Original Message-----
> From: Roper, Matthew D <matthew.d.roper@xxxxxxxxx>
> Sent: Wednesday, October 23, 2024 11:22 PM
> To: Atwood, Matthew S <matthew.s.atwood@xxxxxxxxx>
> Cc: intel-xe@xxxxxxxxxxxxxxxxxxxxx; intel-gfx@xxxxxxxxxxxxxxxxxxxxx; Kandpal,
> Suraj <suraj.kandpal@xxxxxxxxx>
> Subject: Re: [PATCH v4 3/7] drm/i915/xe3lpd: Disable HDCP Line Rekeying for
> Xe3
>
> On Fri, Oct 18, 2024 at 01:03:07PM -0700, Matt Atwood wrote:
> > From: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
> >
> > We need to disable HDCP Line Rekeying for Xe3 when we are using an
> > HDMI encoder.
>
> This is still missing the "why" for this change. Is there a bspec reference that
> gives the details? From the description of the bit itself, it sounds like the
> setting here (for both Xe3 and earlier Xe2) should be based on the HDCP
> version rather than the platform/stepping.
>
> As mentioned previously, this entire function is labeled as "/* WA:
> 16022217614 */" If we're now using this function for something other than
> that specific workaround, then we need to fix/move that comment.
>
>
Bspec: 68933
> Matt
>
> >
> > v2: add additional definition instead of function, commit message typo
> > fix and update.
> > v3: restore lost conditional from v2.
> > v4: subject line and subject message updated, fix the if ladder order,
> > fix the bit definition order.
> >
> > Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
> > Signed-off-by: Matt Atwood <matthew.s.atwood@xxxxxxxxx>
> > ---
> > drivers/gpu/drm/i915/display/intel_hdcp.c | 10 +++++++---
> > drivers/gpu/drm/i915/i915_reg.h | 1 +
> > 2 files changed, 8 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c
> > b/drivers/gpu/drm/i915/display/intel_hdcp.c
> > index ed6aa87403e2..70dfc9d4d6ac 100644
> > --- a/drivers/gpu/drm/i915/display/intel_hdcp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
> > @@ -43,14 +43,18 @@ intel_hdcp_disable_hdcp_line_rekeying(struct
> intel_encoder *encoder,
> > return;
> >
> > if (DISPLAY_VER(display) >= 14) {
> > - if (IS_DISPLAY_VER_STEP(display, IP_VER(14, 0), STEP_D0,
> STEP_FOREVER))
> > - intel_de_rmw(display, MTL_CHICKEN_TRANS(hdcp-
> >cpu_transcoder),
> > - 0, HDCP_LINE_REKEY_DISABLE);
> > + if (DISPLAY_VER(display) >= 30)
> > + intel_de_rmw(display,
> > + TRANS_DDI_FUNC_CTL(display, hdcp-
> >cpu_transcoder),
> > + 0,
> XE3_TRANS_DDI_HDCP_LINE_REKEY_DISABLE);
> > else if (IS_DISPLAY_VER_STEP(display, IP_VER(14, 1), STEP_B0,
> STEP_FOREVER) ||
> > IS_DISPLAY_VER_STEP(display, IP_VER(20, 0),
> STEP_B0, STEP_FOREVER))
> > intel_de_rmw(display,
> > TRANS_DDI_FUNC_CTL(display, hdcp-
> >cpu_transcoder),
> > 0,
> TRANS_DDI_HDCP_LINE_REKEY_DISABLE);
> > + else if (IS_DISPLAY_VER_STEP(display, IP_VER(14, 0), STEP_D0,
> STEP_FOREVER))
> > + intel_de_rmw(display, MTL_CHICKEN_TRANS(hdcp-
> >cpu_transcoder),
> > + 0, HDCP_LINE_REKEY_DISABLE);
> > }
> > }
> >
> > diff --git a/drivers/gpu/drm/i915/i915_reg.h
> > b/drivers/gpu/drm/i915/i915_reg.h index 89e4381f8baa..8d758947f301
> > 100644
> > --- a/drivers/gpu/drm/i915/i915_reg.h
> > +++ b/drivers/gpu/drm/i915/i915_reg.h
> > @@ -3817,6 +3817,7 @@ enum skl_power_gate {
> > #define TRANS_DDI_PVSYNC (1 << 17)
> > #define TRANS_DDI_PHSYNC (1 << 16)
> > #define TRANS_DDI_PORT_SYNC_ENABLE REG_BIT(15)
> > +#define XE3_TRANS_DDI_HDCP_LINE_REKEY_DISABLE REG_BIT(15)
> > #define TRANS_DDI_EDP_INPUT_MASK (7 << 12)
> > #define TRANS_DDI_EDP_INPUT_A_ON (0 << 12)
> > #define TRANS_DDI_EDP_INPUT_A_ONOFF (4 << 12)
> > --
> > 2.45.0
> >
>
> --
> Matt Roper
> Graphics Software Engineer
> Linux GPU Platform Enablement
> Intel Corporation
