The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 9ab57658a608f879469ffa22b723c4539c05a58f Mon Sep 17 00:00:00 2001
From: Sean Paul <seanpaul@xxxxxxxxxxxx>
Date: Tue, 18 Aug 2020 11:38:49 -0400
Subject: [PATCH] drm/i915: Fix sha_text population code
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>
Signed-off-by: Sean Paul <seanpaul@xxxxxxxxxxxx>
Signed-off-by: Ramalingam C <ramalingam.c@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20200818153910.27894-2-sean@xxxxxxxxxx
(cherry picked from commit 1f0882214fd0037b74f245d9be75c31516fed040)
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
index 89a4d294822d..6189b7583277 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
