linux/include/drm/drm_hdcp.h
Ramalingam C 49d85d0342 drm/i915: Check for downstream topology errors
HDCP compliant Repeaters can support max of 127 devices and max
depth of 7 for downstream topology.

If these max limits are exceeded, repeater will set the
topology error flags MAX_CASCADE_EXCEEDED and/or MAX_DEVS_EXCEEDED
in Bstatus followed by asserting READY/CP_IRQ for HDCP transmitter.

This patch check for these error flags as soon as READY bit is asserted.

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
[seanpaul fixed checkpatch alignment issue]
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1516254488-4971-5-git-send-email-ramalingam.c@intel.com
2018-01-18 17:56:02 -05:00

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1.2 KiB
C

/* SPDX-License-Identifier: MIT */
/*
* Copyright (C) 2017 Google, Inc.
*
* Authors:
* Sean Paul <seanpaul@chromium.org>
*/
#ifndef _DRM_HDCP_H_INCLUDED_
#define _DRM_HDCP_H_INCLUDED_
/* Period of hdcp checks (to ensure we're still authenticated) */
#define DRM_HDCP_CHECK_PERIOD_MS (128 * 16)
/* Shared lengths/masks between HDMI/DVI/DisplayPort */
#define DRM_HDCP_AN_LEN 8
#define DRM_HDCP_BSTATUS_LEN 2
#define DRM_HDCP_KSV_LEN 5
#define DRM_HDCP_RI_LEN 2
#define DRM_HDCP_V_PRIME_PART_LEN 4
#define DRM_HDCP_V_PRIME_NUM_PARTS 5
#define DRM_HDCP_NUM_DOWNSTREAM(x) (x & 0x3f)
#define DRM_HDCP_MAX_CASCADE_EXCEEDED(x) (x & BIT(3))
#define DRM_HDCP_MAX_DEVICE_EXCEEDED(x) (x & BIT(7))
/* Slave address for the HDCP registers in the receiver */
#define DRM_HDCP_DDC_ADDR 0x3A
/* HDCP register offsets for HDMI/DVI devices */
#define DRM_HDCP_DDC_BKSV 0x00
#define DRM_HDCP_DDC_RI_PRIME 0x08
#define DRM_HDCP_DDC_AKSV 0x10
#define DRM_HDCP_DDC_AN 0x18
#define DRM_HDCP_DDC_V_PRIME(h) (0x20 + h * 4)
#define DRM_HDCP_DDC_BCAPS 0x40
#define DRM_HDCP_DDC_BCAPS_REPEATER_PRESENT BIT(6)
#define DRM_HDCP_DDC_BCAPS_KSV_FIFO_READY BIT(5)
#define DRM_HDCP_DDC_BSTATUS 0x41
#define DRM_HDCP_DDC_KSV_FIFO 0x43
#endif