/* SPDX-License-Identifier: MIT */
/*
 * Copyright (C) 2017 Google, Inc.
 *
 * Authors:
 * Sean Paul <seanpaul@chromium.org>
 */

#include <linux/component.h>
#include <linux/i2c.h>
#include <linux/random.h>

#include <drm/drm_hdcp.h>
#include <drm/i915_component.h>

#include "i915_reg.h"
#include "intel_drv.h"
#include "intel_hdcp.h"
#include "intel_sideband.h"

#define KEY_LOAD_TRIES  5
#define ENCRYPT_STATUS_CHANGE_TIMEOUT_MS        50
#define HDCP2_LC_RETRY_CNT                      3

static
bool intel_hdcp_is_ksv_valid(u8 *ksv)
{
        int i, ones = 0;
        /* KSV has 20 1's and 20 0's */
        for (i = 0; i < DRM_HDCP_KSV_LEN; i++)
                ones += hweight8(ksv[i]);
        if (ones != 20)
                return false;

        return true;
}

static
int intel_hdcp_read_valid_bksv(struct intel_digital_port *intel_dig_port,
                               const struct intel_hdcp_shim *shim, u8 *bksv)
{
        int ret, i, tries = 2;

        /* HDCP spec states that we must retry the bksv if it is invalid */
        for (i = 0; i < tries; i++) {
                ret = shim->read_bksv(intel_dig_port, bksv);
                if (ret)
                        return ret;
                if (intel_hdcp_is_ksv_valid(bksv))
                        break;
        }
        if (i == tries) {
                DRM_DEBUG_KMS("Bksv is invalid\n");
                return -ENODEV;
        }

        return 0;
}

/* Is HDCP1.4 capable on Platform and Sink */
bool intel_hdcp_capable(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        const struct intel_hdcp_shim *shim = connector->hdcp.shim;
        bool capable = false;
        u8 bksv[5];

        if (!shim)
                return capable;

        if (shim->hdcp_capable) {
                shim->hdcp_capable(intel_dig_port, &capable);
        } else {
                if (!intel_hdcp_read_valid_bksv(intel_dig_port, shim, bksv))
                        capable = true;
        }

        return capable;
}

/* Is HDCP2.2 capable on Platform and Sink */
bool intel_hdcp2_capable(struct intel_connector *connector)
{
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct intel_hdcp *hdcp = &connector->hdcp;
        bool capable = false;

        /* I915 support for HDCP2.2 */
        if (!hdcp->hdcp2_supported)
                return false;

        /* MEI interface is solid */
        mutex_lock(&dev_priv->hdcp_comp_mutex);
        if (!dev_priv->hdcp_comp_added ||  !dev_priv->hdcp_master) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return false;
        }
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        /* Sink's capability for HDCP2.2 */
        hdcp->shim->hdcp_2_2_capable(intel_dig_port, &capable);

        return capable;
}

static inline bool intel_hdcp_in_use(struct intel_connector *connector)
{
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        enum port port = connector->encoder->port;
        u32 reg;

        reg = I915_READ(PORT_HDCP_STATUS(port));
        return reg & HDCP_STATUS_ENC;
}

static inline bool intel_hdcp2_in_use(struct intel_connector *connector)
{
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        enum port port = connector->encoder->port;
        u32 reg;

        reg = I915_READ(HDCP2_STATUS_DDI(port));
        return reg & LINK_ENCRYPTION_STATUS;
}

static int intel_hdcp_poll_ksv_fifo(struct intel_digital_port *intel_dig_port,
                                    const struct intel_hdcp_shim *shim)
{
        int ret, read_ret;
        bool ksv_ready;

        /* Poll for ksv list ready (spec says max time allowed is 5s) */
        ret = __wait_for(read_ret = shim->read_ksv_ready(intel_dig_port,
                                                         &ksv_ready),
                         read_ret || ksv_ready, 5 * 1000 * 1000, 1000,
                         100 * 1000);
        if (ret)
                return ret;
        if (read_ret)
                return read_ret;
        if (!ksv_ready)
                return -ETIMEDOUT;

        return 0;
}

static bool hdcp_key_loadable(struct drm_i915_private *dev_priv)
{
        struct i915_power_domains *power_domains = &dev_priv->power_domains;
        struct i915_power_well *power_well;
        enum i915_power_well_id id;
        bool enabled = false;

        /*
         * On HSW and BDW, Display HW loads the Key as soon as Display resumes.
         * On all BXT+, SW can load the keys only when the PW#1 is turned on.
         */
        if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
                id = HSW_DISP_PW_GLOBAL;
        else
                id = SKL_DISP_PW_1;

        mutex_lock(&power_domains->lock);

        /* PG1 (power well #1) needs to be enabled */
        for_each_power_well(dev_priv, power_well) {
                if (power_well->desc->id == id) {
                        enabled = power_well->desc->ops->is_enabled(dev_priv,
                                                                    power_well);
                        break;
                }
        }
        mutex_unlock(&power_domains->lock);

        /*
         * Another req for hdcp key loadability is enabled state of pll for
         * cdclk. Without active crtc we wont land here. So we are assuming that
         * cdclk is already on.
         */

        return enabled;
}

static void intel_hdcp_clear_keys(struct drm_i915_private *dev_priv)
{
        I915_WRITE(HDCP_KEY_CONF, HDCP_CLEAR_KEYS_TRIGGER);
        I915_WRITE(HDCP_KEY_STATUS, HDCP_KEY_LOAD_DONE | HDCP_KEY_LOAD_STATUS |
                   HDCP_FUSE_IN_PROGRESS | HDCP_FUSE_ERROR | HDCP_FUSE_DONE);
}

static int intel_hdcp_load_keys(struct drm_i915_private *dev_priv)
{
        int ret;
        u32 val;

        val = I915_READ(HDCP_KEY_STATUS);
        if ((val & HDCP_KEY_LOAD_DONE) && (val & HDCP_KEY_LOAD_STATUS))
                return 0;

        /*
         * On HSW and BDW HW loads the HDCP1.4 Key when Display comes
         * out of reset. So if Key is not already loaded, its an error state.
         */
        if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
                if (!(I915_READ(HDCP_KEY_STATUS) & HDCP_KEY_LOAD_DONE))
                        return -ENXIO;

        /*
         * Initiate loading the HDCP key from fuses.
         *
         * BXT+ platforms, HDCP key needs to be loaded by SW. Only Gen 9
         * platforms except BXT and GLK, differ in the key load trigger process
         * from other platforms. So GEN9_BC uses the GT Driver Mailbox i/f.
         */
        if (IS_GEN9_BC(dev_priv)) {
                ret = sandybridge_pcode_write(dev_priv,
                                              SKL_PCODE_LOAD_HDCP_KEYS, 1);
                if (ret) {
                        DRM_ERROR("Failed to initiate HDCP key load (%d)\n",
                                  ret);
                        return ret;
                }
        } else {
                I915_WRITE(HDCP_KEY_CONF, HDCP_KEY_LOAD_TRIGGER);
        }

        /* Wait for the keys to load (500us) */
        ret = __intel_wait_for_register(&dev_priv->uncore, HDCP_KEY_STATUS,
                                        HDCP_KEY_LOAD_DONE, HDCP_KEY_LOAD_DONE,
                                        10, 1, &val);
        if (ret)
                return ret;
        else if (!(val & HDCP_KEY_LOAD_STATUS))
                return -ENXIO;

        /* Send Aksv over to PCH display for use in authentication */
        I915_WRITE(HDCP_KEY_CONF, HDCP_AKSV_SEND_TRIGGER);

        return 0;
}

/* Returns updated SHA-1 index */
static int intel_write_sha_text(struct drm_i915_private *dev_priv, u32 sha_text)
{
        I915_WRITE(HDCP_SHA_TEXT, sha_text);
        if (intel_wait_for_register(&dev_priv->uncore, HDCP_REP_CTL,
                                    HDCP_SHA1_READY, HDCP_SHA1_READY, 1)) {
                DRM_ERROR("Timed out waiting for SHA1 ready\n");
                return -ETIMEDOUT;
        }
        return 0;
}

static
u32 intel_hdcp_get_repeater_ctl(struct intel_digital_port *intel_dig_port)
{
        enum port port = intel_dig_port->base.port;
        switch (port) {
        case PORT_A:
                return HDCP_DDIA_REP_PRESENT | HDCP_DDIA_SHA1_M0;
        case PORT_B:
                return HDCP_DDIB_REP_PRESENT | HDCP_DDIB_SHA1_M0;
        case PORT_C:
                return HDCP_DDIC_REP_PRESENT | HDCP_DDIC_SHA1_M0;
        case PORT_D:
                return HDCP_DDID_REP_PRESENT | HDCP_DDID_SHA1_M0;
        case PORT_E:
                return HDCP_DDIE_REP_PRESENT | HDCP_DDIE_SHA1_M0;
        default:
                break;
        }
        DRM_ERROR("Unknown port %d\n", port);
        return -EINVAL;
}

static
int intel_hdcp_validate_v_prime(struct intel_digital_port *intel_dig_port,
                                const struct intel_hdcp_shim *shim,
                                u8 *ksv_fifo, u8 num_downstream, u8 *bstatus)
{
        struct drm_i915_private *dev_priv;
        u32 vprime, sha_text, sha_leftovers, rep_ctl;
        int ret, i, j, sha_idx;

        dev_priv = intel_dig_port->base.base.dev->dev_private;

        /* Process V' values from the receiver */
        for (i = 0; i < DRM_HDCP_V_PRIME_NUM_PARTS; i++) {
                ret = shim->read_v_prime_part(intel_dig_port, i, &vprime);
                if (ret)
                        return ret;
                I915_WRITE(HDCP_SHA_V_PRIME(i), vprime);
        }

        /*
         * We need to write the concatenation of all device KSVs, BINFO (DP) ||
         * BSTATUS (HDMI), and M0 (which is added via HDCP_REP_CTL). This byte
         * stream is written via the HDCP_SHA_TEXT register in 32-bit
         * increments. Every 64 bytes, we need to write HDCP_REP_CTL again. This
         * index will keep track of our progress through the 64 bytes as well as
         * helping us work the 40-bit KSVs through our 32-bit register.
         *
         * NOTE: data passed via HDCP_SHA_TEXT should be big-endian
         */
        sha_idx = 0;
        sha_text = 0;
        sha_leftovers = 0;
        rep_ctl = intel_hdcp_get_repeater_ctl(intel_dig_port);
        I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_32);
        for (i = 0; i < num_downstream; i++) {
                unsigned int sha_empty;
                u8 *ksv = &ksv_fifo[i * DRM_HDCP_KSV_LEN];

                /* 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);

                ret = intel_write_sha_text(dev_priv, sha_text);
                if (ret < 0)
                        return ret;

                /* Programming guide writes this every 64 bytes */
                sha_idx += sizeof(sha_text);
                if (!(sha_idx % 64))
                        I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_32);

                /* Store the leftover bytes from the ksv in sha_text */
                sha_leftovers = DRM_HDCP_KSV_LEN - sha_empty;
                sha_text = 0;
                for (j = 0; j < sha_leftovers; j++)
                        sha_text |= ksv[sha_empty + j] <<
                                        ((sizeof(sha_text) - j - 1) * 8);

                /*
                 * If we still have room in sha_text for more data, continue.
                 * Otherwise, write it out immediately.
                 */
                if (sizeof(sha_text) > sha_leftovers)
                        continue;

                ret = intel_write_sha_text(dev_priv, sha_text);
                if (ret < 0)
                        return ret;
                sha_leftovers = 0;
                sha_text = 0;
                sha_idx += sizeof(sha_text);
        }

        /*
         * We need to write BINFO/BSTATUS, and M0 now. Depending on how many
         * bytes are leftover from the last ksv, we might be able to fit them
         * all in sha_text (first 2 cases), or we might need to split them up
         * into 2 writes (last 2 cases).
         */
        if (sha_leftovers == 0) {
                /* Write 16 bits of text, 16 bits of M0 */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_16);
                ret = intel_write_sha_text(dev_priv,
                                           bstatus[0] << 8 | bstatus[1]);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);

                /* Write 32 bits of M0 */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_0);
                ret = intel_write_sha_text(dev_priv, 0);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);

                /* Write 16 bits of M0 */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_16);
                ret = intel_write_sha_text(dev_priv, 0);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);

        } else if (sha_leftovers == 1) {
                /* Write 24 bits of text, 8 bits of M0 */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_24);
                sha_text |= bstatus[0] << 16 | bstatus[1] << 8;
                /* Only 24-bits of data, must be in the LSB */
                sha_text = (sha_text & 0xffffff00) >> 8;
                ret = intel_write_sha_text(dev_priv, sha_text);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);

                /* Write 32 bits of M0 */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_0);
                ret = intel_write_sha_text(dev_priv, 0);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);

                /* Write 24 bits of M0 */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_8);
                ret = intel_write_sha_text(dev_priv, 0);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);

        } else if (sha_leftovers == 2) {
                /* Write 32 bits of text */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_32);
                sha_text |= bstatus[0] << 24 | bstatus[1] << 16;
                ret = intel_write_sha_text(dev_priv, sha_text);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);

                /* Write 64 bits of M0 */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_0);
                for (i = 0; i < 2; i++) {
                        ret = intel_write_sha_text(dev_priv, 0);
                        if (ret < 0)
                                return ret;
                        sha_idx += sizeof(sha_text);
                }
        } else if (sha_leftovers == 3) {
                /* Write 32 bits of text */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_32);
                sha_text |= bstatus[0] << 24;
                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 */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_8);
                ret = intel_write_sha_text(dev_priv, bstatus[1]);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);

                /* Write 32 bits of M0 */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_0);
                ret = intel_write_sha_text(dev_priv, 0);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);

                /* Write 8 bits of M0 */
                I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_24);
                ret = intel_write_sha_text(dev_priv, 0);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);
        } else {
                DRM_DEBUG_KMS("Invalid number of leftovers %d\n",
                              sha_leftovers);
                return -EINVAL;
        }

        I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_TEXT_32);
        /* Fill up to 64-4 bytes with zeros (leave the last write for length) */
        while ((sha_idx % 64) < (64 - sizeof(sha_text))) {
                ret = intel_write_sha_text(dev_priv, 0);
                if (ret < 0)
                        return ret;
                sha_idx += sizeof(sha_text);
        }

        /*
         * Last write gets the length of the concatenation in bits. That is:
         *  - 5 bytes per device
         *  - 10 bytes for BINFO/BSTATUS(2), M0(8)
         */
        sha_text = (num_downstream * 5 + 10) * 8;
        ret = intel_write_sha_text(dev_priv, sha_text);
        if (ret < 0)
                return ret;

        /* Tell the HW we're done with the hash and wait for it to ACK */
        I915_WRITE(HDCP_REP_CTL, rep_ctl | HDCP_SHA1_COMPLETE_HASH);
        if (intel_wait_for_register(&dev_priv->uncore, HDCP_REP_CTL,
                                    HDCP_SHA1_COMPLETE,
                                    HDCP_SHA1_COMPLETE, 1)) {
                DRM_ERROR("Timed out waiting for SHA1 complete\n");
                return -ETIMEDOUT;
        }
        if (!(I915_READ(HDCP_REP_CTL) & HDCP_SHA1_V_MATCH)) {
                DRM_DEBUG_KMS("SHA-1 mismatch, HDCP failed\n");
                return -ENXIO;
        }

        return 0;
}

/* Implements Part 2 of the HDCP authorization procedure */
static
int intel_hdcp_auth_downstream(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        const struct intel_hdcp_shim *shim = connector->hdcp.shim;
        struct drm_device *dev = connector->base.dev;
        u8 bstatus[2], num_downstream, *ksv_fifo;
        int ret, i, tries = 3;

        ret = intel_hdcp_poll_ksv_fifo(intel_dig_port, shim);
        if (ret) {
                DRM_DEBUG_KMS("KSV list failed to become ready (%d)\n", ret);
                return ret;
        }

        ret = shim->read_bstatus(intel_dig_port, bstatus);
        if (ret)
                return ret;

        if (DRM_HDCP_MAX_DEVICE_EXCEEDED(bstatus[0]) ||
            DRM_HDCP_MAX_CASCADE_EXCEEDED(bstatus[1])) {
                DRM_DEBUG_KMS("Max Topology Limit Exceeded\n");
                return -EPERM;
        }

        /*
         * When repeater reports 0 device count, HDCP1.4 spec allows disabling
         * the HDCP encryption. That implies that repeater can't have its own
         * display. As there is no consumption of encrypted content in the
         * repeater with 0 downstream devices, we are failing the
         * authentication.
         */
        num_downstream = DRM_HDCP_NUM_DOWNSTREAM(bstatus[0]);
        if (num_downstream == 0)
                return -EINVAL;

        ksv_fifo = kcalloc(DRM_HDCP_KSV_LEN, num_downstream, GFP_KERNEL);
        if (!ksv_fifo)
                return -ENOMEM;

        ret = shim->read_ksv_fifo(intel_dig_port, num_downstream, ksv_fifo);
        if (ret)
                goto err;

        if (drm_hdcp_check_ksvs_revoked(dev, ksv_fifo, num_downstream)) {
                DRM_ERROR("Revoked Ksv(s) in ksv_fifo\n");
                ret = -EPERM;
                goto err;
        }

        /*
         * When V prime mismatches, DP Spec mandates re-read of
         * V prime atleast twice.
         */
        for (i = 0; i < tries; i++) {
                ret = intel_hdcp_validate_v_prime(intel_dig_port, shim,
                                                  ksv_fifo, num_downstream,
                                                  bstatus);
                if (!ret)
                        break;
        }

        if (i == tries) {
                DRM_DEBUG_KMS("V Prime validation failed.(%d)\n", ret);
                goto err;
        }

        DRM_DEBUG_KMS("HDCP is enabled (%d downstream devices)\n",
                      num_downstream);
        ret = 0;
err:
        kfree(ksv_fifo);
        return ret;
}

/* Implements Part 1 of the HDCP authorization procedure */
static int intel_hdcp_auth(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct intel_hdcp *hdcp = &connector->hdcp;
        struct drm_device *dev = connector->base.dev;
        const struct intel_hdcp_shim *shim = hdcp->shim;
        struct drm_i915_private *dev_priv;
        enum port port;
        unsigned long r0_prime_gen_start;
        int ret, i, tries = 2;
        union {
                u32 reg[2];
                u8 shim[DRM_HDCP_AN_LEN];
        } an;
        union {
                u32 reg[2];
                u8 shim[DRM_HDCP_KSV_LEN];
        } bksv;
        union {
                u32 reg;
                u8 shim[DRM_HDCP_RI_LEN];
        } ri;
        bool repeater_present, hdcp_capable;

        dev_priv = intel_dig_port->base.base.dev->dev_private;

        port = intel_dig_port->base.port;

        /*
         * Detects whether the display is HDCP capable. Although we check for
         * valid Bksv below, the HDCP over DP spec requires that we check
         * whether the display supports HDCP before we write An. For HDMI
         * displays, this is not necessary.
         */
        if (shim->hdcp_capable) {
                ret = shim->hdcp_capable(intel_dig_port, &hdcp_capable);
                if (ret)
                        return ret;
                if (!hdcp_capable) {
                        DRM_DEBUG_KMS("Panel is not HDCP capable\n");
                        return -EINVAL;
                }
        }

        /* Initialize An with 2 random values and acquire it */
        for (i = 0; i < 2; i++)
                I915_WRITE(PORT_HDCP_ANINIT(port), get_random_u32());
        I915_WRITE(PORT_HDCP_CONF(port), HDCP_CONF_CAPTURE_AN);

        /* Wait for An to be acquired */
        if (intel_wait_for_register(&dev_priv->uncore, PORT_HDCP_STATUS(port),
                                    HDCP_STATUS_AN_READY,
                                    HDCP_STATUS_AN_READY, 1)) {
                DRM_ERROR("Timed out waiting for An\n");
                return -ETIMEDOUT;
        }

        an.reg[0] = I915_READ(PORT_HDCP_ANLO(port));
        an.reg[1] = I915_READ(PORT_HDCP_ANHI(port));
        ret = shim->write_an_aksv(intel_dig_port, an.shim);
        if (ret)
                return ret;

        r0_prime_gen_start = jiffies;

        memset(&bksv, 0, sizeof(bksv));

        ret = intel_hdcp_read_valid_bksv(intel_dig_port, shim, bksv.shim);
        if (ret < 0)
                return ret;

        if (drm_hdcp_check_ksvs_revoked(dev, bksv.shim, 1)) {
                DRM_ERROR("BKSV is revoked\n");
                return -EPERM;
        }

        I915_WRITE(PORT_HDCP_BKSVLO(port), bksv.reg[0]);
        I915_WRITE(PORT_HDCP_BKSVHI(port), bksv.reg[1]);

        ret = shim->repeater_present(intel_dig_port, &repeater_present);
        if (ret)
                return ret;
        if (repeater_present)
                I915_WRITE(HDCP_REP_CTL,
                           intel_hdcp_get_repeater_ctl(intel_dig_port));

        ret = shim->toggle_signalling(intel_dig_port, true);
        if (ret)
                return ret;

        I915_WRITE(PORT_HDCP_CONF(port), HDCP_CONF_AUTH_AND_ENC);

        /* Wait for R0 ready */
        if (wait_for(I915_READ(PORT_HDCP_STATUS(port)) &
                     (HDCP_STATUS_R0_READY | HDCP_STATUS_ENC), 1)) {
                DRM_ERROR("Timed out waiting for R0 ready\n");
                return -ETIMEDOUT;
        }

        /*
         * Wait for R0' to become available. The spec says 100ms from Aksv, but
         * some monitors can take longer than this. We'll set the timeout at
         * 300ms just to be sure.
         *
         * On DP, there's an R0_READY bit available but no such bit
         * exists on HDMI. Since the upper-bound is the same, we'll just do
         * the stupid thing instead of polling on one and not the other.
         */
        wait_remaining_ms_from_jiffies(r0_prime_gen_start, 300);

        tries = 3;

        /*
         * DP HDCP Spec mandates the two more reattempt to read R0, incase
         * of R0 mismatch.
         */
        for (i = 0; i < tries; i++) {
                ri.reg = 0;
                ret = shim->read_ri_prime(intel_dig_port, ri.shim);
                if (ret)
                        return ret;
                I915_WRITE(PORT_HDCP_RPRIME(port), ri.reg);

                /* Wait for Ri prime match */
                if (!wait_for(I915_READ(PORT_HDCP_STATUS(port)) &
                    (HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC), 1))
                        break;
        }

        if (i == tries) {
                DRM_DEBUG_KMS("Timed out waiting for Ri prime match (%x)\n",
                              I915_READ(PORT_HDCP_STATUS(port)));
                return -ETIMEDOUT;
        }

        /* Wait for encryption confirmation */
        if (intel_wait_for_register(&dev_priv->uncore, PORT_HDCP_STATUS(port),
                                    HDCP_STATUS_ENC, HDCP_STATUS_ENC,
                                    ENCRYPT_STATUS_CHANGE_TIMEOUT_MS)) {
                DRM_ERROR("Timed out waiting for encryption\n");
                return -ETIMEDOUT;
        }

        /*
         * XXX: If we have MST-connected devices, we need to enable encryption
         * on those as well.
         */

        if (repeater_present)
                return intel_hdcp_auth_downstream(connector);

        DRM_DEBUG_KMS("HDCP is enabled (no repeater present)\n");
        return 0;
}

static int _intel_hdcp_disable(struct intel_connector *connector)
{
        struct intel_hdcp *hdcp = &connector->hdcp;
        struct drm_i915_private *dev_priv = connector->base.dev->dev_private;
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        enum port port = intel_dig_port->base.port;
        int ret;

        DRM_DEBUG_KMS("[%s:%d] HDCP is being disabled...\n",
                      connector->base.name, connector->base.base.id);

        hdcp->hdcp_encrypted = false;
        I915_WRITE(PORT_HDCP_CONF(port), 0);
        if (intel_wait_for_register(&dev_priv->uncore,
                                    PORT_HDCP_STATUS(port), ~0, 0,
                                    ENCRYPT_STATUS_CHANGE_TIMEOUT_MS)) {
                DRM_ERROR("Failed to disable HDCP, timeout clearing status\n");
                return -ETIMEDOUT;
        }

        ret = hdcp->shim->toggle_signalling(intel_dig_port, false);
        if (ret) {
                DRM_ERROR("Failed to disable HDCP signalling\n");
                return ret;
        }

        DRM_DEBUG_KMS("HDCP is disabled\n");
        return 0;
}

static int _intel_hdcp_enable(struct intel_connector *connector)
{
        struct intel_hdcp *hdcp = &connector->hdcp;
        struct drm_i915_private *dev_priv = connector->base.dev->dev_private;
        int i, ret, tries = 3;

        DRM_DEBUG_KMS("[%s:%d] HDCP is being enabled...\n",
                      connector->base.name, connector->base.base.id);

        if (!hdcp_key_loadable(dev_priv)) {
                DRM_ERROR("HDCP key Load is not possible\n");
                return -ENXIO;
        }

        for (i = 0; i < KEY_LOAD_TRIES; i++) {
                ret = intel_hdcp_load_keys(dev_priv);
                if (!ret)
                        break;
                intel_hdcp_clear_keys(dev_priv);
        }
        if (ret) {
                DRM_ERROR("Could not load HDCP keys, (%d)\n", ret);
                return ret;
        }

        /* Incase of authentication failures, HDCP spec expects reauth. */
        for (i = 0; i < tries; i++) {
                ret = intel_hdcp_auth(connector);
                if (!ret) {
                        hdcp->hdcp_encrypted = true;
                        return 0;
                }

                DRM_DEBUG_KMS("HDCP Auth failure (%d)\n", ret);

                /* Ensuring HDCP encryption and signalling are stopped. */
                _intel_hdcp_disable(connector);
        }

        DRM_DEBUG_KMS("HDCP authentication failed (%d tries/%d)\n", tries, ret);
        return ret;
}

static inline
struct intel_connector *intel_hdcp_to_connector(struct intel_hdcp *hdcp)
{
        return container_of(hdcp, struct intel_connector, hdcp);
}

/* Implements Part 3 of the HDCP authorization procedure */
static int intel_hdcp_check_link(struct intel_connector *connector)
{
        struct intel_hdcp *hdcp = &connector->hdcp;
        struct drm_i915_private *dev_priv = connector->base.dev->dev_private;
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        enum port port = intel_dig_port->base.port;
        int ret = 0;

        mutex_lock(&hdcp->mutex);

        /* Check_link valid only when HDCP1.4 is enabled */
        if (hdcp->value != DRM_MODE_CONTENT_PROTECTION_ENABLED ||
            !hdcp->hdcp_encrypted) {
                ret = -EINVAL;
                goto out;
        }

        if (WARN_ON(!intel_hdcp_in_use(connector))) {
                DRM_ERROR("%s:%d HDCP link stopped encryption,%x\n",
                          connector->base.name, connector->base.base.id,
                          I915_READ(PORT_HDCP_STATUS(port)));
                ret = -ENXIO;
                hdcp->value = DRM_MODE_CONTENT_PROTECTION_DESIRED;
                schedule_work(&hdcp->prop_work);
                goto out;
        }

        if (hdcp->shim->check_link(intel_dig_port)) {
                if (hdcp->value != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
                        hdcp->value = DRM_MODE_CONTENT_PROTECTION_ENABLED;
                        schedule_work(&hdcp->prop_work);
                }
                goto out;
        }

        DRM_DEBUG_KMS("[%s:%d] HDCP link failed, retrying authentication\n",
                      connector->base.name, connector->base.base.id);

        ret = _intel_hdcp_disable(connector);
        if (ret) {
                DRM_ERROR("Failed to disable hdcp (%d)\n", ret);
                hdcp->value = DRM_MODE_CONTENT_PROTECTION_DESIRED;
                schedule_work(&hdcp->prop_work);
                goto out;
        }

        ret = _intel_hdcp_enable(connector);
        if (ret) {
                DRM_ERROR("Failed to enable hdcp (%d)\n", ret);
                hdcp->value = DRM_MODE_CONTENT_PROTECTION_DESIRED;
                schedule_work(&hdcp->prop_work);
                goto out;
        }

out:
        mutex_unlock(&hdcp->mutex);
        return ret;
}

static void intel_hdcp_prop_work(struct work_struct *work)
{
        struct intel_hdcp *hdcp = container_of(work, struct intel_hdcp,
                                               prop_work);
        struct intel_connector *connector = intel_hdcp_to_connector(hdcp);
        struct drm_device *dev = connector->base.dev;
        struct drm_connector_state *state;

        drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
        mutex_lock(&hdcp->mutex);

        /*
         * This worker is only used to flip between ENABLED/DESIRED. Either of
         * those to UNDESIRED is handled by core. If value == UNDESIRED,
         * we're running just after hdcp has been disabled, so just exit
         */
        if (hdcp->value != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
                state = connector->base.state;
                state->content_protection = hdcp->value;
        }

        mutex_unlock(&hdcp->mutex);
        drm_modeset_unlock(&dev->mode_config.connection_mutex);
}

bool is_hdcp_supported(struct drm_i915_private *dev_priv, enum port port)
{
        /* PORT E doesn't have HDCP, and PORT F is disabled */
        return INTEL_GEN(dev_priv) >= 9 && port < PORT_E;
}

static int
hdcp2_prepare_ake_init(struct intel_connector *connector,
                       struct hdcp2_ake_init *ake_data)
{
        struct hdcp_port_data *data = &connector->hdcp.port_data;
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->initiate_hdcp2_session(comp->mei_dev, data, ake_data);
        if (ret)
                DRM_DEBUG_KMS("Prepare_ake_init failed. %d\n", ret);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int
hdcp2_verify_rx_cert_prepare_km(struct intel_connector *connector,
                                struct hdcp2_ake_send_cert *rx_cert,
                                bool *paired,
                                struct hdcp2_ake_no_stored_km *ek_pub_km,
                                size_t *msg_sz)
{
        struct hdcp_port_data *data = &connector->hdcp.port_data;
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->verify_receiver_cert_prepare_km(comp->mei_dev, data,
                                                         rx_cert, paired,
                                                         ek_pub_km, msg_sz);
        if (ret < 0)
                DRM_DEBUG_KMS("Verify rx_cert failed. %d\n", ret);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int hdcp2_verify_hprime(struct intel_connector *connector,
                               struct hdcp2_ake_send_hprime *rx_hprime)
{
        struct hdcp_port_data *data = &connector->hdcp.port_data;
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->verify_hprime(comp->mei_dev, data, rx_hprime);
        if (ret < 0)
                DRM_DEBUG_KMS("Verify hprime failed. %d\n", ret);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int
hdcp2_store_pairing_info(struct intel_connector *connector,
                         struct hdcp2_ake_send_pairing_info *pairing_info)
{
        struct hdcp_port_data *data = &connector->hdcp.port_data;
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->store_pairing_info(comp->mei_dev, data, pairing_info);
        if (ret < 0)
                DRM_DEBUG_KMS("Store pairing info failed. %d\n", ret);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int
hdcp2_prepare_lc_init(struct intel_connector *connector,
                      struct hdcp2_lc_init *lc_init)

{
        struct hdcp_port_data *data = &connector->hdcp.port_data;
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->initiate_locality_check(comp->mei_dev, data, lc_init);
        if (ret < 0)
                DRM_DEBUG_KMS("Prepare lc_init failed. %d\n", ret);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int
hdcp2_verify_lprime(struct intel_connector *connector,
                    struct hdcp2_lc_send_lprime *rx_lprime)
{
        struct hdcp_port_data *data = &connector->hdcp.port_data;
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->verify_lprime(comp->mei_dev, data, rx_lprime);
        if (ret < 0)
                DRM_DEBUG_KMS("Verify L_Prime failed. %d\n", ret);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int hdcp2_prepare_skey(struct intel_connector *connector,
                              struct hdcp2_ske_send_eks *ske_data)
{
        struct hdcp_port_data *data = &connector->hdcp.port_data;
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->get_session_key(comp->mei_dev, data, ske_data);
        if (ret < 0)
                DRM_DEBUG_KMS("Get session key failed. %d\n", ret);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int
hdcp2_verify_rep_topology_prepare_ack(struct intel_connector *connector,
                                      struct hdcp2_rep_send_receiverid_list
                                                                *rep_topology,
                                      struct hdcp2_rep_send_ack *rep_send_ack)
{
        struct hdcp_port_data *data = &connector->hdcp.port_data;
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->repeater_check_flow_prepare_ack(comp->mei_dev, data,
                                                         rep_topology,
                                                         rep_send_ack);
        if (ret < 0)
                DRM_DEBUG_KMS("Verify rep topology failed. %d\n", ret);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int
hdcp2_verify_mprime(struct intel_connector *connector,
                    struct hdcp2_rep_stream_ready *stream_ready)
{
        struct hdcp_port_data *data = &connector->hdcp.port_data;
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->verify_mprime(comp->mei_dev, data, stream_ready);
        if (ret < 0)
                DRM_DEBUG_KMS("Verify mprime failed. %d\n", ret);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int hdcp2_authenticate_port(struct intel_connector *connector)
{
        struct hdcp_port_data *data = &connector->hdcp.port_data;
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->enable_hdcp_authentication(comp->mei_dev, data);
        if (ret < 0)
                DRM_DEBUG_KMS("Enable hdcp auth failed. %d\n", ret);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int hdcp2_close_mei_session(struct intel_connector *connector)
{
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct i915_hdcp_comp_master *comp;
        int ret;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        comp = dev_priv->hdcp_master;

        if (!comp || !comp->ops) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return -EINVAL;
        }

        ret = comp->ops->close_hdcp_session(comp->mei_dev,
                                             &connector->hdcp.port_data);
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return ret;
}

static int hdcp2_deauthenticate_port(struct intel_connector *connector)
{
        return hdcp2_close_mei_session(connector);
}

/* Authentication flow starts from here */
static int hdcp2_authentication_key_exchange(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct intel_hdcp *hdcp = &connector->hdcp;
        struct drm_device *dev = connector->base.dev;
        union {
                struct hdcp2_ake_init ake_init;
                struct hdcp2_ake_send_cert send_cert;
                struct hdcp2_ake_no_stored_km no_stored_km;
                struct hdcp2_ake_send_hprime send_hprime;
                struct hdcp2_ake_send_pairing_info pairing_info;
        } msgs;
        const struct intel_hdcp_shim *shim = hdcp->shim;
        size_t size;
        int ret;

        /* Init for seq_num */
        hdcp->seq_num_v = 0;
        hdcp->seq_num_m = 0;

        ret = hdcp2_prepare_ake_init(connector, &msgs.ake_init);
        if (ret < 0)
                return ret;

        ret = shim->write_2_2_msg(intel_dig_port, &msgs.ake_init,
                                  sizeof(msgs.ake_init));
        if (ret < 0)
                return ret;

        ret = shim->read_2_2_msg(intel_dig_port, HDCP_2_2_AKE_SEND_CERT,
                                 &msgs.send_cert, sizeof(msgs.send_cert));
        if (ret < 0)
                return ret;

        if (msgs.send_cert.rx_caps[0] != HDCP_2_2_RX_CAPS_VERSION_VAL)
                return -EINVAL;

        hdcp->is_repeater = HDCP_2_2_RX_REPEATER(msgs.send_cert.rx_caps[2]);

        if (drm_hdcp_check_ksvs_revoked(dev, msgs.send_cert.cert_rx.receiver_id,
                                        1)) {
                DRM_ERROR("Receiver ID is revoked\n");
                return -EPERM;
        }

        /*
         * Here msgs.no_stored_km will hold msgs corresponding to the km
         * stored also.
         */
        ret = hdcp2_verify_rx_cert_prepare_km(connector, &msgs.send_cert,
                                              &hdcp->is_paired,
                                              &msgs.no_stored_km, &size);
        if (ret < 0)
                return ret;

        ret = shim->write_2_2_msg(intel_dig_port, &msgs.no_stored_km, size);
        if (ret < 0)
                return ret;

        ret = shim->read_2_2_msg(intel_dig_port, HDCP_2_2_AKE_SEND_HPRIME,
                                 &msgs.send_hprime, sizeof(msgs.send_hprime));
        if (ret < 0)
                return ret;

        ret = hdcp2_verify_hprime(connector, &msgs.send_hprime);
        if (ret < 0)
                return ret;

        if (!hdcp->is_paired) {
                /* Pairing is required */
                ret = shim->read_2_2_msg(intel_dig_port,
                                         HDCP_2_2_AKE_SEND_PAIRING_INFO,
                                         &msgs.pairing_info,
                                         sizeof(msgs.pairing_info));
                if (ret < 0)
                        return ret;

                ret = hdcp2_store_pairing_info(connector, &msgs.pairing_info);
                if (ret < 0)
                        return ret;
                hdcp->is_paired = true;
        }

        return 0;
}

static int hdcp2_locality_check(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct intel_hdcp *hdcp = &connector->hdcp;
        union {
                struct hdcp2_lc_init lc_init;
                struct hdcp2_lc_send_lprime send_lprime;
        } msgs;
        const struct intel_hdcp_shim *shim = hdcp->shim;
        int tries = HDCP2_LC_RETRY_CNT, ret, i;

        for (i = 0; i < tries; i++) {
                ret = hdcp2_prepare_lc_init(connector, &msgs.lc_init);
                if (ret < 0)
                        continue;

                ret = shim->write_2_2_msg(intel_dig_port, &msgs.lc_init,
                                      sizeof(msgs.lc_init));
                if (ret < 0)
                        continue;

                ret = shim->read_2_2_msg(intel_dig_port,
                                         HDCP_2_2_LC_SEND_LPRIME,
                                         &msgs.send_lprime,
                                         sizeof(msgs.send_lprime));
                if (ret < 0)
                        continue;

                ret = hdcp2_verify_lprime(connector, &msgs.send_lprime);
                if (!ret)
                        break;
        }

        return ret;
}

static int hdcp2_session_key_exchange(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct intel_hdcp *hdcp = &connector->hdcp;
        struct hdcp2_ske_send_eks send_eks;
        int ret;

        ret = hdcp2_prepare_skey(connector, &send_eks);
        if (ret < 0)
                return ret;

        ret = hdcp->shim->write_2_2_msg(intel_dig_port, &send_eks,
                                        sizeof(send_eks));
        if (ret < 0)
                return ret;

        return 0;
}

static
int hdcp2_propagate_stream_management_info(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct intel_hdcp *hdcp = &connector->hdcp;
        union {
                struct hdcp2_rep_stream_manage stream_manage;
                struct hdcp2_rep_stream_ready stream_ready;
        } msgs;
        const struct intel_hdcp_shim *shim = hdcp->shim;
        int ret;

        /* Prepare RepeaterAuth_Stream_Manage msg */
        msgs.stream_manage.msg_id = HDCP_2_2_REP_STREAM_MANAGE;
        drm_hdcp_cpu_to_be24(msgs.stream_manage.seq_num_m, hdcp->seq_num_m);

        /* K no of streams is fixed as 1. Stored as big-endian. */
        msgs.stream_manage.k = cpu_to_be16(1);

        /* For HDMI this is forced to be 0x0. For DP SST also this is 0x0. */
        msgs.stream_manage.streams[0].stream_id = 0;
        msgs.stream_manage.streams[0].stream_type = hdcp->content_type;

        /* Send it to Repeater */
        ret = shim->write_2_2_msg(intel_dig_port, &msgs.stream_manage,
                                  sizeof(msgs.stream_manage));
        if (ret < 0)
                return ret;

        ret = shim->read_2_2_msg(intel_dig_port, HDCP_2_2_REP_STREAM_READY,
                                 &msgs.stream_ready, sizeof(msgs.stream_ready));
        if (ret < 0)
                return ret;

        hdcp->port_data.seq_num_m = hdcp->seq_num_m;
        hdcp->port_data.streams[0].stream_type = hdcp->content_type;

        ret = hdcp2_verify_mprime(connector, &msgs.stream_ready);
        if (ret < 0)
                return ret;

        hdcp->seq_num_m++;

        if (hdcp->seq_num_m > HDCP_2_2_SEQ_NUM_MAX) {
                DRM_DEBUG_KMS("seq_num_m roll over.\n");
                return -1;
        }

        return 0;
}

static
int hdcp2_authenticate_repeater_topology(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct intel_hdcp *hdcp = &connector->hdcp;
        struct drm_device *dev = connector->base.dev;
        union {
                struct hdcp2_rep_send_receiverid_list recvid_list;
                struct hdcp2_rep_send_ack rep_ack;
        } msgs;
        const struct intel_hdcp_shim *shim = hdcp->shim;
        u32 seq_num_v, device_cnt;
        u8 *rx_info;
        int ret;

        ret = shim->read_2_2_msg(intel_dig_port, HDCP_2_2_REP_SEND_RECVID_LIST,
                                 &msgs.recvid_list, sizeof(msgs.recvid_list));
        if (ret < 0)
                return ret;

        rx_info = msgs.recvid_list.rx_info;

        if (HDCP_2_2_MAX_CASCADE_EXCEEDED(rx_info[1]) ||
            HDCP_2_2_MAX_DEVS_EXCEEDED(rx_info[1])) {
                DRM_DEBUG_KMS("Topology Max Size Exceeded\n");
                return -EINVAL;
        }

        /* Converting and Storing the seq_num_v to local variable as DWORD */
        seq_num_v =
                drm_hdcp_be24_to_cpu((const u8 *)msgs.recvid_list.seq_num_v);

        if (seq_num_v < hdcp->seq_num_v) {
                /* Roll over of the seq_num_v from repeater. Reauthenticate. */
                DRM_DEBUG_KMS("Seq_num_v roll over.\n");
                return -EINVAL;
        }

        device_cnt = (HDCP_2_2_DEV_COUNT_HI(rx_info[0]) << 4 |
                      HDCP_2_2_DEV_COUNT_LO(rx_info[1]));
        if (drm_hdcp_check_ksvs_revoked(dev, msgs.recvid_list.receiver_ids,
                                        device_cnt)) {
                DRM_ERROR("Revoked receiver ID(s) is in list\n");
                return -EPERM;
        }

        ret = hdcp2_verify_rep_topology_prepare_ack(connector,
                                                    &msgs.recvid_list,
                                                    &msgs.rep_ack);
        if (ret < 0)
                return ret;

        hdcp->seq_num_v = seq_num_v;
        ret = shim->write_2_2_msg(intel_dig_port, &msgs.rep_ack,
                                  sizeof(msgs.rep_ack));
        if (ret < 0)
                return ret;

        return 0;
}

static int hdcp2_authenticate_repeater(struct intel_connector *connector)
{
        int ret;

        ret = hdcp2_authenticate_repeater_topology(connector);
        if (ret < 0)
                return ret;

        return hdcp2_propagate_stream_management_info(connector);
}

static int hdcp2_authenticate_sink(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct intel_hdcp *hdcp = &connector->hdcp;
        const struct intel_hdcp_shim *shim = hdcp->shim;
        int ret;

        ret = hdcp2_authentication_key_exchange(connector);
        if (ret < 0) {
                DRM_DEBUG_KMS("AKE Failed. Err : %d\n", ret);
                return ret;
        }

        ret = hdcp2_locality_check(connector);
        if (ret < 0) {
                DRM_DEBUG_KMS("Locality Check failed. Err : %d\n", ret);
                return ret;
        }

        ret = hdcp2_session_key_exchange(connector);
        if (ret < 0) {
                DRM_DEBUG_KMS("SKE Failed. Err : %d\n", ret);
                return ret;
        }

        if (shim->config_stream_type) {
                ret = shim->config_stream_type(intel_dig_port,
                                               hdcp->is_repeater,
                                               hdcp->content_type);
                if (ret < 0)
                        return ret;
        }

        if (hdcp->is_repeater) {
                ret = hdcp2_authenticate_repeater(connector);
                if (ret < 0) {
                        DRM_DEBUG_KMS("Repeater Auth Failed. Err: %d\n", ret);
                        return ret;
                }
        }

        hdcp->port_data.streams[0].stream_type = hdcp->content_type;
        ret = hdcp2_authenticate_port(connector);
        if (ret < 0)
                return ret;

        return ret;
}

static int hdcp2_enable_encryption(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct intel_hdcp *hdcp = &connector->hdcp;
        enum port port = connector->encoder->port;
        int ret;

        WARN_ON(I915_READ(HDCP2_STATUS_DDI(port)) & LINK_ENCRYPTION_STATUS);

        if (hdcp->shim->toggle_signalling) {
                ret = hdcp->shim->toggle_signalling(intel_dig_port, true);
                if (ret) {
                        DRM_ERROR("Failed to enable HDCP signalling. %d\n",
                                  ret);
                        return ret;
                }
        }

        if (I915_READ(HDCP2_STATUS_DDI(port)) & LINK_AUTH_STATUS) {
                /* Link is Authenticated. Now set for Encryption */
                I915_WRITE(HDCP2_CTL_DDI(port),
                           I915_READ(HDCP2_CTL_DDI(port)) |
                           CTL_LINK_ENCRYPTION_REQ);
        }

        ret = intel_wait_for_register(&dev_priv->uncore, HDCP2_STATUS_DDI(port),
                                      LINK_ENCRYPTION_STATUS,
                                      LINK_ENCRYPTION_STATUS,
                                      ENCRYPT_STATUS_CHANGE_TIMEOUT_MS);

        return ret;
}

static int hdcp2_disable_encryption(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct intel_hdcp *hdcp = &connector->hdcp;
        enum port port = connector->encoder->port;
        int ret;

        WARN_ON(!(I915_READ(HDCP2_STATUS_DDI(port)) & LINK_ENCRYPTION_STATUS));

        I915_WRITE(HDCP2_CTL_DDI(port),
                   I915_READ(HDCP2_CTL_DDI(port)) & ~CTL_LINK_ENCRYPTION_REQ);

        ret = intel_wait_for_register(&dev_priv->uncore, HDCP2_STATUS_DDI(port),
                                      LINK_ENCRYPTION_STATUS, 0x0,
                                      ENCRYPT_STATUS_CHANGE_TIMEOUT_MS);
        if (ret == -ETIMEDOUT)
                DRM_DEBUG_KMS("Disable Encryption Timedout");

        if (hdcp->shim->toggle_signalling) {
                ret = hdcp->shim->toggle_signalling(intel_dig_port, false);
                if (ret) {
                        DRM_ERROR("Failed to disable HDCP signalling. %d\n",
                                  ret);
                        return ret;
                }
        }

        return ret;
}

static int hdcp2_authenticate_and_encrypt(struct intel_connector *connector)
{
        int ret, i, tries = 3;

        for (i = 0; i < tries; i++) {
                ret = hdcp2_authenticate_sink(connector);
                if (!ret)
                        break;

                /* Clearing the mei hdcp session */
                DRM_DEBUG_KMS("HDCP2.2 Auth %d of %d Failed.(%d)\n",
                              i + 1, tries, ret);
                if (hdcp2_deauthenticate_port(connector) < 0)
                        DRM_DEBUG_KMS("Port deauth failed.\n");
        }

        if (i != tries) {
                /*
                 * Ensuring the required 200mSec min time interval between
                 * Session Key Exchange and encryption.
                 */
                msleep(HDCP_2_2_DELAY_BEFORE_ENCRYPTION_EN);
                ret = hdcp2_enable_encryption(connector);
                if (ret < 0) {
                        DRM_DEBUG_KMS("Encryption Enable Failed.(%d)\n", ret);
                        if (hdcp2_deauthenticate_port(connector) < 0)
                                DRM_DEBUG_KMS("Port deauth failed.\n");
                }
        }

        return ret;
}

static int _intel_hdcp2_enable(struct intel_connector *connector)
{
        struct intel_hdcp *hdcp = &connector->hdcp;
        int ret;

        DRM_DEBUG_KMS("[%s:%d] HDCP2.2 is being enabled. Type: %d\n",
                      connector->base.name, connector->base.base.id,
                      hdcp->content_type);

        ret = hdcp2_authenticate_and_encrypt(connector);
        if (ret) {
                DRM_DEBUG_KMS("HDCP2 Type%d  Enabling Failed. (%d)\n",
                              hdcp->content_type, ret);
                return ret;
        }

        DRM_DEBUG_KMS("[%s:%d] HDCP2.2 is enabled. Type %d\n",
                      connector->base.name, connector->base.base.id,
                      hdcp->content_type);

        hdcp->hdcp2_encrypted = true;
        return 0;
}

static int _intel_hdcp2_disable(struct intel_connector *connector)
{
        int ret;

        DRM_DEBUG_KMS("[%s:%d] HDCP2.2 is being Disabled\n",
                      connector->base.name, connector->base.base.id);

        ret = hdcp2_disable_encryption(connector);

        if (hdcp2_deauthenticate_port(connector) < 0)
                DRM_DEBUG_KMS("Port deauth failed.\n");

        connector->hdcp.hdcp2_encrypted = false;

        return ret;
}

/* Implements the Link Integrity Check for HDCP2.2 */
static int intel_hdcp2_check_link(struct intel_connector *connector)
{
        struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct intel_hdcp *hdcp = &connector->hdcp;
        enum port port = connector->encoder->port;
        int ret = 0;

        mutex_lock(&hdcp->mutex);

        /* hdcp2_check_link is expected only when HDCP2.2 is Enabled */
        if (hdcp->value != DRM_MODE_CONTENT_PROTECTION_ENABLED ||
            !hdcp->hdcp2_encrypted) {
                ret = -EINVAL;
                goto out;
        }

        if (WARN_ON(!intel_hdcp2_in_use(connector))) {
                DRM_ERROR("HDCP2.2 link stopped the encryption, %x\n",
                          I915_READ(HDCP2_STATUS_DDI(port)));
                ret = -ENXIO;
                hdcp->value = DRM_MODE_CONTENT_PROTECTION_DESIRED;
                schedule_work(&hdcp->prop_work);
                goto out;
        }

        ret = hdcp->shim->check_2_2_link(intel_dig_port);
        if (ret == HDCP_LINK_PROTECTED) {
                if (hdcp->value != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
                        hdcp->value = DRM_MODE_CONTENT_PROTECTION_ENABLED;
                        schedule_work(&hdcp->prop_work);
                }
                goto out;
        }

        if (ret == HDCP_TOPOLOGY_CHANGE) {
                if (hdcp->value == DRM_MODE_CONTENT_PROTECTION_UNDESIRED)
                        goto out;

                DRM_DEBUG_KMS("HDCP2.2 Downstream topology change\n");
                ret = hdcp2_authenticate_repeater_topology(connector);
                if (!ret) {
                        hdcp->value = DRM_MODE_CONTENT_PROTECTION_ENABLED;
                        schedule_work(&hdcp->prop_work);
                        goto out;
                }
                DRM_DEBUG_KMS("[%s:%d] Repeater topology auth failed.(%d)\n",
                              connector->base.name, connector->base.base.id,
                              ret);
        } else {
                DRM_DEBUG_KMS("[%s:%d] HDCP2.2 link failed, retrying auth\n",
                              connector->base.name, connector->base.base.id);
        }

        ret = _intel_hdcp2_disable(connector);
        if (ret) {
                DRM_ERROR("[%s:%d] Failed to disable hdcp2.2 (%d)\n",
                          connector->base.name, connector->base.base.id, ret);
                hdcp->value = DRM_MODE_CONTENT_PROTECTION_DESIRED;
                schedule_work(&hdcp->prop_work);
                goto out;
        }

        ret = _intel_hdcp2_enable(connector);
        if (ret) {
                DRM_DEBUG_KMS("[%s:%d] Failed to enable hdcp2.2 (%d)\n",
                              connector->base.name, connector->base.base.id,
                              ret);
                hdcp->value = DRM_MODE_CONTENT_PROTECTION_DESIRED;
                schedule_work(&hdcp->prop_work);
                goto out;
        }

out:
        mutex_unlock(&hdcp->mutex);
        return ret;
}

static void intel_hdcp_check_work(struct work_struct *work)
{
        struct intel_hdcp *hdcp = container_of(to_delayed_work(work),
                                               struct intel_hdcp,
                                               check_work);
        struct intel_connector *connector = intel_hdcp_to_connector(hdcp);

        if (!intel_hdcp2_check_link(connector))
                schedule_delayed_work(&hdcp->check_work,
                                      DRM_HDCP2_CHECK_PERIOD_MS);
        else if (!intel_hdcp_check_link(connector))
                schedule_delayed_work(&hdcp->check_work,
                                      DRM_HDCP_CHECK_PERIOD_MS);
}

static int i915_hdcp_component_bind(struct device *i915_kdev,
                                    struct device *mei_kdev, void *data)
{
        struct drm_i915_private *dev_priv = kdev_to_i915(i915_kdev);

        DRM_DEBUG("I915 HDCP comp bind\n");
        mutex_lock(&dev_priv->hdcp_comp_mutex);
        dev_priv->hdcp_master = (struct i915_hdcp_comp_master *)data;
        dev_priv->hdcp_master->mei_dev = mei_kdev;
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        return 0;
}

static void i915_hdcp_component_unbind(struct device *i915_kdev,
                                       struct device *mei_kdev, void *data)
{
        struct drm_i915_private *dev_priv = kdev_to_i915(i915_kdev);

        DRM_DEBUG("I915 HDCP comp unbind\n");
        mutex_lock(&dev_priv->hdcp_comp_mutex);
        dev_priv->hdcp_master = NULL;
        mutex_unlock(&dev_priv->hdcp_comp_mutex);
}

static const struct component_ops i915_hdcp_component_ops = {
        .bind   = i915_hdcp_component_bind,
        .unbind = i915_hdcp_component_unbind,
};

static inline int initialize_hdcp_port_data(struct intel_connector *connector)
{
        struct intel_hdcp *hdcp = &connector->hdcp;
        struct hdcp_port_data *data = &hdcp->port_data;

        data->port = connector->encoder->port;
        data->port_type = (u8)HDCP_PORT_TYPE_INTEGRATED;
        data->protocol = (u8)hdcp->shim->protocol;

        data->k = 1;
        if (!data->streams)
                data->streams = kcalloc(data->k,
                                        sizeof(struct hdcp2_streamid_type),
                                        GFP_KERNEL);
        if (!data->streams) {
                DRM_ERROR("Out of Memory\n");
                return -ENOMEM;
        }

        data->streams[0].stream_id = 0;
        data->streams[0].stream_type = hdcp->content_type;

        return 0;
}

static bool is_hdcp2_supported(struct drm_i915_private *dev_priv)
{
        if (!IS_ENABLED(CONFIG_INTEL_MEI_HDCP))
                return false;

        return (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv) ||
                IS_KABYLAKE(dev_priv));
}

void intel_hdcp_component_init(struct drm_i915_private *dev_priv)
{
        int ret;

        if (!is_hdcp2_supported(dev_priv))
                return;

        mutex_lock(&dev_priv->hdcp_comp_mutex);
        WARN_ON(dev_priv->hdcp_comp_added);

        dev_priv->hdcp_comp_added = true;
        mutex_unlock(&dev_priv->hdcp_comp_mutex);
        ret = component_add_typed(dev_priv->drm.dev, &i915_hdcp_component_ops,
                                  I915_COMPONENT_HDCP);
        if (ret < 0) {
                DRM_DEBUG_KMS("Failed at component add(%d)\n", ret);
                mutex_lock(&dev_priv->hdcp_comp_mutex);
                dev_priv->hdcp_comp_added = false;
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return;
        }
}

static void intel_hdcp2_init(struct intel_connector *connector)
{
        struct intel_hdcp *hdcp = &connector->hdcp;
        int ret;

        ret = initialize_hdcp_port_data(connector);
        if (ret) {
                DRM_DEBUG_KMS("Mei hdcp data init failed\n");
                return;
        }

        hdcp->hdcp2_supported = true;
}

int intel_hdcp_init(struct intel_connector *connector,
                    const struct intel_hdcp_shim *shim)
{
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct intel_hdcp *hdcp = &connector->hdcp;
        int ret;

        if (!shim)
                return -EINVAL;

        ret = drm_connector_attach_content_protection_property(&connector->base);
        if (ret)
                return ret;

        hdcp->shim = shim;
        mutex_init(&hdcp->mutex);
        INIT_DELAYED_WORK(&hdcp->check_work, intel_hdcp_check_work);
        INIT_WORK(&hdcp->prop_work, intel_hdcp_prop_work);

        if (is_hdcp2_supported(dev_priv))
                intel_hdcp2_init(connector);
        init_waitqueue_head(&hdcp->cp_irq_queue);

        return 0;
}

int intel_hdcp_enable(struct intel_connector *connector)
{
        struct intel_hdcp *hdcp = &connector->hdcp;
        unsigned long check_link_interval = DRM_HDCP_CHECK_PERIOD_MS;
        int ret = -EINVAL;

        if (!hdcp->shim)
                return -ENOENT;

        mutex_lock(&hdcp->mutex);
        WARN_ON(hdcp->value == DRM_MODE_CONTENT_PROTECTION_ENABLED);

        /*
         * Considering that HDCP2.2 is more secure than HDCP1.4, If the setup
         * is capable of HDCP2.2, it is preferred to use HDCP2.2.
         */
        if (intel_hdcp2_capable(connector)) {
                ret = _intel_hdcp2_enable(connector);
                if (!ret)
                        check_link_interval = DRM_HDCP2_CHECK_PERIOD_MS;
        }

        /* When HDCP2.2 fails, HDCP1.4 will be attempted */
        if (ret && intel_hdcp_capable(connector)) {
                ret = _intel_hdcp_enable(connector);
        }

        if (!ret) {
                schedule_delayed_work(&hdcp->check_work, check_link_interval);
                hdcp->value = DRM_MODE_CONTENT_PROTECTION_ENABLED;
                schedule_work(&hdcp->prop_work);
        }

        mutex_unlock(&hdcp->mutex);
        return ret;
}

int intel_hdcp_disable(struct intel_connector *connector)
{
        struct intel_hdcp *hdcp = &connector->hdcp;
        int ret = 0;

        if (!hdcp->shim)
                return -ENOENT;

        mutex_lock(&hdcp->mutex);

        if (hdcp->value != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
                hdcp->value = DRM_MODE_CONTENT_PROTECTION_UNDESIRED;
                if (hdcp->hdcp2_encrypted)
                        ret = _intel_hdcp2_disable(connector);
                else if (hdcp->hdcp_encrypted)
                        ret = _intel_hdcp_disable(connector);
        }

        mutex_unlock(&hdcp->mutex);
        cancel_delayed_work_sync(&hdcp->check_work);
        return ret;
}

void intel_hdcp_component_fini(struct drm_i915_private *dev_priv)
{
        mutex_lock(&dev_priv->hdcp_comp_mutex);
        if (!dev_priv->hdcp_comp_added) {
                mutex_unlock(&dev_priv->hdcp_comp_mutex);
                return;
        }

        dev_priv->hdcp_comp_added = false;
        mutex_unlock(&dev_priv->hdcp_comp_mutex);

        component_del(dev_priv->drm.dev, &i915_hdcp_component_ops);
}

void intel_hdcp_cleanup(struct intel_connector *connector)
{
        if (!connector->hdcp.shim)
                return;

        mutex_lock(&connector->hdcp.mutex);
        kfree(connector->hdcp.port_data.streams);
        mutex_unlock(&connector->hdcp.mutex);
}

void intel_hdcp_atomic_check(struct drm_connector *connector,
                             struct drm_connector_state *old_state,
                             struct drm_connector_state *new_state)
{
        u64 old_cp = old_state->content_protection;
        u64 new_cp = new_state->content_protection;
        struct drm_crtc_state *crtc_state;

        if (!new_state->crtc) {
                /*
                 * If the connector is being disabled with CP enabled, mark it
                 * desired so it's re-enabled when the connector is brought back
                 */
                if (old_cp == DRM_MODE_CONTENT_PROTECTION_ENABLED)
                        new_state->content_protection =
                                DRM_MODE_CONTENT_PROTECTION_DESIRED;
                return;
        }

        /*
         * Nothing to do if the state didn't change, or HDCP was activated since
         * the last commit
         */
        if (old_cp == new_cp ||
            (old_cp == DRM_MODE_CONTENT_PROTECTION_DESIRED &&
             new_cp == DRM_MODE_CONTENT_PROTECTION_ENABLED))
                return;

        crtc_state = drm_atomic_get_new_crtc_state(new_state->state,
                                                   new_state->crtc);
        crtc_state->mode_changed = true;
}

/* Handles the CP_IRQ raised from the DP HDCP sink */
void intel_hdcp_handle_cp_irq(struct intel_connector *connector)
{
        struct intel_hdcp *hdcp = &connector->hdcp;

        if (!hdcp->shim)
                return;

        atomic_inc(&connector->hdcp.cp_irq_count);
        wake_up_all(&connector->hdcp.cp_irq_queue);

        schedule_delayed_work(&hdcp->check_work, 0);
}