[PATCH] drm/xe/hdcp: Add check to remove hdcp2 compatibility

[Kandpal, Suraj]

> -----Original Message-----
> From: Ceraolo Spurio, Daniele <daniele.ceraolospurio at intel.com>
> Sent: Thursday, October 24, 2024 9:03 PM
> To: Kandpal, Suraj <suraj.kandpal at intel.com>; intel-xe at lists.freedesktop.org;
> intel-gfx at lists.freedesktop.org
> Cc: Nautiyal, Ankit K <ankit.k.nautiyal at intel.com>; Ghimiray, Himal Prasad
> <himal.prasad.ghimiray at intel.com>
> Subject: Re: [PATCH] drm/xe/hdcp: Add check to remove hdcp2 compatibility
> 
> 
> 
> 
> On 10/22/2024 12:29 AM, Suraj Kandpal wrote:
> > Add check to remove HDCP2 compatibility from BMG as it does not have
> > GSC which ends up causing warning when we try to get reference of GSC
> > FW.
> >
> > Fixes: 89d030804831 ("drm/xe/hdcp: Fix condition for hdcp gsc cs
> > requirement")
> > Fixes: 883631771038 ("drm/i915/mtl: Add HDCP GSC interface")
> > Signed-off-by: Suraj Kandpal <suraj.kandpal at intel.com>
> > Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
> > Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray at intel.com>
> > ---
> >   drivers/gpu/drm/i915/display/intel_hdcp_gsc.c | 3 ++-
> >   drivers/gpu/drm/xe/display/xe_hdcp_gsc.c      | 4 +++-
> >   2 files changed, 5 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_hdcp_gsc.c
> > b/drivers/gpu/drm/i915/display/intel_hdcp_gsc.c
> > index 55965844d829..2c1d0ee8cec2 100644
> > --- a/drivers/gpu/drm/i915/display/intel_hdcp_gsc.c
> > +++ b/drivers/gpu/drm/i915/display/intel_hdcp_gsc.c
> > @@ -21,7 +21,8 @@ struct intel_hdcp_gsc_message {
> >
> >   bool intel_hdcp_gsc_cs_required(struct intel_display *display)
> >   {
> > -	return DISPLAY_VER(display) >= 14;
> > +	return DISPLAY_VER(display) >= 14 &&
> > +		DISPLAY_VER_FULL(display) != IP_VER(14, 1);
> >   }
> >
> >   bool intel_hdcp_gsc_check_status(struct intel_display *display) diff
> > --git a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> > b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> > index 231677129a35..efa3441c249c 100644
> > --- a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> > +++ b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> > @@ -8,6 +8,7 @@
> >   #include <linux/delay.h>
> >
> >   #include "abi/gsc_command_header_abi.h"
> > +#include "i915_drv.h"
> >   #include "intel_hdcp_gsc.h"
> >   #include "intel_hdcp_gsc_message.h"
> >   #include "xe_bo.h"
> > @@ -32,7 +33,8 @@ struct intel_hdcp_gsc_message {
> >
> >   bool intel_hdcp_gsc_cs_required(struct intel_display *display)
> >   {
> > -	return DISPLAY_VER(display) >= 14;
> > +	return DISPLAY_VER(display) >= 14 &&
> > +		DISPLAY_VER_FULL(display) != IP_VER(14, 1);
> 
> I don't think this is the correct check or the correct location. BMG does
> require the GSC for HDCP, so intel_hdcp_gsc_cs_required() should still return
> true; it's just that we've decided not to support GSC FW loading on the
> platform, so we can't support HDCP2.x. Also note that the this might change
> and/or it might apply to other platform in the future, so any check needs to
> be done based on GSC support and not platform/display ID.
> 
> IMO when intel_hdcp_gsc_cs_required() returns true, the caller should check
> if the GSC FW is defined (or if the GSCCS is available) and if it is not return
> that hdcp2 is not supported due to unmet prerequsites and fallback to 1.4
> without printing any errors.
> 

Here is the thing before this I thought that should have worked too but after hdcp_gsc_cs_required()
We call intel_hdcp_gsc_check_status() which has the following check

if (!gsc && !xe_uc_fw_is_enabled(&gsc->fw)) {
                drm_dbg_kms(&xe->drm,
                            "GSC Components not ready for HDCP2.x\n");
                return false;
 }

And this should have returned from here but it does not it goes ahead and tries to get a xe_pm_runtime()
Which causes it to shout out loud which is currently causing a lot of noise in CI

Regards,
Suraj Kandpal

> Daniele
> 
> >   }
> >
> >   bool intel_hdcp_gsc_check_status(struct intel_display *display)