On 2020-04-29 at 15:54:47 -0400, Sean Paul wrote: > From: Sean Paul <seanpaul@xxxxxxxxxxxx> > > This patch fixes a few bugs: > > 1- We weren't taking into account sha_leftovers when adding multiple > ksvs to sha_text. As such, we were or'ing the end of ksv[j - 1] with > the beginning of ksv[j] > > 2- In the sha_leftovers == 2 and sha_leftovers == 3 case, bstatus was > being placed on the wrong half of sha_text, overlapping the leftover > ksv value > > 3- In the sha_leftovers == 2 case, we need to manually terminate the > byte stream with 0x80 since the hardware doesn't have enough room to > add it after writing M0 > > The upside is that all of the HDCP supported HDMI repeaters I could > find on Amazon just strip HDCP anyways, so it turns out to be _really_ > hard to hit any of these cases without an MST hub, which is not (yet) > supported. Oh, and the sha_leftovers == 1 case works perfectly! > > Fixes: ee5e5e7a5e0f (drm/i915: Add HDCP framework + base implementation) > Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: Ramalingam C <ramalingam.c@xxxxxxxxx> > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> > Cc: Sean Paul <seanpaul@xxxxxxxxxxxx> > Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> > Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> > Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx > Cc: <stable@xxxxxxxxxxxxxxx> # v4.17+ > Reviewed-by: Ramalingam C <ramalingam.c@xxxxxxxxx> Just reconfirming my R-b here. Reviewed-by: Ramalingam C <ramalingam.c@xxxxxxxxx> > Signed-off-by: Sean Paul <seanpaul@xxxxxxxxxxxx> > Link: https://patchwork.freedesktop.org/patch/msgid/20191203173638.94919-2-sean@xxxxxxxxxx #v1 > Link: https://patchwork.freedesktop.org/patch/msgid/20191212190230.188505-2-sean@xxxxxxxxxx #v2 > Link: https://patchwork.freedesktop.org/patch/msgid/20200117193103.156821-2-sean@xxxxxxxxxx #v3 > Link: https://patchwork.freedesktop.org/patch/msgid/20200218220242.107265-2-sean@xxxxxxxxxx #v4 > Link: https://patchwork.freedesktop.org/patch/msgid/20200305201236.152307-2-sean@xxxxxxxxxx #v5 > > Changes in v2: > -None > Changes in v3: > -None > Changes in v4: > -Rebased on intel_de_write changes > Changes in v5: > -None > Changes in v6: > -None > --- > drivers/gpu/drm/i915/display/intel_hdcp.c | 26 +++++++++++++++++------ > include/drm/drm_hdcp.h | 3 +++ > 2 files changed, 23 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c > index 2cbc4619b4ce..525658fd201f 100644 > --- a/drivers/gpu/drm/i915/display/intel_hdcp.c > +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c > @@ -336,8 +336,10 @@ int intel_hdcp_validate_v_prime(struct intel_connector *connector, > > /* Fill up the empty slots in sha_text and write it out */ > sha_empty = sizeof(sha_text) - sha_leftovers; > - for (j = 0; j < sha_empty; j++) > - sha_text |= ksv[j] << ((sizeof(sha_text) - j - 1) * 8); > + for (j = 0; j < sha_empty; j++) { > + u8 off = ((sizeof(sha_text) - j - 1 - sha_leftovers) * 8); > + sha_text |= ksv[j] << off; > + } > > ret = intel_write_sha_text(dev_priv, sha_text); > if (ret < 0) > @@ -435,7 +437,7 @@ int intel_hdcp_validate_v_prime(struct intel_connector *connector, > /* Write 32 bits of text */ > intel_de_write(dev_priv, HDCP_REP_CTL, > rep_ctl | HDCP_SHA1_TEXT_32); > - sha_text |= bstatus[0] << 24 | bstatus[1] << 16; > + sha_text |= bstatus[0] << 8 | bstatus[1]; > ret = intel_write_sha_text(dev_priv, sha_text); > if (ret < 0) > return ret; > @@ -450,17 +452,29 @@ int intel_hdcp_validate_v_prime(struct intel_connector *connector, > return ret; > sha_idx += sizeof(sha_text); > } > + > + /* > + * Terminate the SHA-1 stream by hand. For the other leftover > + * cases this is appended by the hardware. > + */ > + intel_de_write(dev_priv, HDCP_REP_CTL, > + rep_ctl | HDCP_SHA1_TEXT_32); > + sha_text = DRM_HDCP_SHA1_TERMINATOR << 24; > + ret = intel_write_sha_text(dev_priv, sha_text); > + if (ret < 0) > + return ret; > + sha_idx += sizeof(sha_text); > } else if (sha_leftovers == 3) { > - /* Write 32 bits of text */ > + /* Write 32 bits of text (filled from LSB) */ > intel_de_write(dev_priv, HDCP_REP_CTL, > rep_ctl | HDCP_SHA1_TEXT_32); > - sha_text |= bstatus[0] << 24; > + sha_text |= bstatus[0]; > ret = intel_write_sha_text(dev_priv, sha_text); > if (ret < 0) > return ret; > sha_idx += sizeof(sha_text); > > - /* Write 8 bits of text, 24 bits of M0 */ > + /* Write 8 bits of text (filled from LSB), 24 bits of M0 */ > intel_de_write(dev_priv, HDCP_REP_CTL, > rep_ctl | HDCP_SHA1_TEXT_8); > ret = intel_write_sha_text(dev_priv, bstatus[1]); > diff --git a/include/drm/drm_hdcp.h b/include/drm/drm_hdcp.h > index c6bab4986a65..fe58dbb46962 100644 > --- a/include/drm/drm_hdcp.h > +++ b/include/drm/drm_hdcp.h > @@ -29,6 +29,9 @@ > /* Slave address for the HDCP registers in the receiver */ > #define DRM_HDCP_DDC_ADDR 0x3A > > +/* Value to use at the end of the SHA-1 bytestream used for repeaters */ > +#define DRM_HDCP_SHA1_TERMINATOR 0x80 > + > /* HDCP register offsets for HDMI/DVI devices */ > #define DRM_HDCP_DDC_BKSV 0x00 > #define DRM_HDCP_DDC_RI_PRIME 0x08 > -- > Sean Paul, Software Engineer, Google / Chromium OS >
