root/drivers/gpu/drm/amd/display/modules/hdcp/hdcp1_transition.c
/*
 * Copyright 2019 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: AMD
 *
 */

#include "hdcp.h"

enum mod_hdcp_status mod_hdcp_hdcp1_transition(struct mod_hdcp *hdcp,
                struct mod_hdcp_event_context *event_ctx,
                struct mod_hdcp_transition_input_hdcp1 *input,
                struct mod_hdcp_output *output)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
        struct mod_hdcp_connection *conn = &hdcp->connection;
        struct mod_hdcp_link_adjustment *adjust = &hdcp->connection.link.adjust;

        switch (current_state(hdcp)) {
        case H1_A0_WAIT_FOR_ACTIVE_RX:
                if (input->bksv_read != PASS || input->bcaps_read != PASS) {
                        /* 1A-04: repeatedly attempts on port access failure */
                        callback_in_ms(500, output);
                        increment_stay_counter(hdcp);
                        break;
                }
                callback_in_ms(0, output);
                set_state_id(hdcp, output, H1_A1_EXCHANGE_KSVS);
                break;
        case H1_A1_EXCHANGE_KSVS:
                if (input->create_session != PASS) {
                        /* out of sync with psp state */
                        adjust->hdcp1.disable = 1;
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                } else if (input->an_write != PASS ||
                                input->aksv_write != PASS ||
                                input->bksv_read != PASS ||
                                input->bksv_validation != PASS ||
                                input->ainfo_write == FAIL) {
                        /* 1A-05: consider invalid bksv a failure */
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                }
                callback_in_ms(300, output);
                set_state_id(hdcp, output,
                        H1_A2_COMPUTATIONS_A3_VALIDATE_RX_A6_TEST_FOR_REPEATER);
                break;
        case H1_A2_COMPUTATIONS_A3_VALIDATE_RX_A6_TEST_FOR_REPEATER:
                if (input->bcaps_read != PASS ||
                                input->r0p_read != PASS) {
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                } else if (input->rx_validation != PASS) {
                        /* 1A-06: consider invalid r0' a failure */
                        /* 1A-08: consider bksv listed in SRM a failure */
                        /*
                         * some slow RX will fail rx validation when it is
                         * not ready. give it more time to react before retry.
                         */
                        fail_and_restart_in_ms(1000, &status, output);
                        break;
                } else if (!conn->is_repeater && input->encryption != PASS) {
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                }
                if (conn->is_repeater) {
                        callback_in_ms(0, output);
                        set_watchdog_in_ms(hdcp, 5000, output);
                        set_state_id(hdcp, output, H1_A8_WAIT_FOR_READY);
                } else {
                        callback_in_ms(0, output);
                        set_state_id(hdcp, output, H1_A45_AUTHENTICATED);
                        set_auth_complete(hdcp, output);
                }
                break;
        case H1_A45_AUTHENTICATED:
                if (input->link_maintenance == FAIL) {
                        /* 1A-07: consider invalid ri' a failure */
                        /* 1A-07a: consider read ri' not returned a failure */
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                }
                callback_in_ms(500, output);
                increment_stay_counter(hdcp);
                break;
        case H1_A8_WAIT_FOR_READY:
                if (input->ready_check != PASS) {
                        if (event_ctx->event ==
                                        MOD_HDCP_EVENT_WATCHDOG_TIMEOUT) {
                                /* 1B-03: fail hdcp on ksv list READY timeout */
                                /* prevent black screen in next attempt */
                                adjust->hdcp1.postpone_encryption = 1;
                                fail_and_restart_in_ms(0, &status, output);
                        } else {
                                /* continue ksv list READY polling*/
                                callback_in_ms(500, output);
                                increment_stay_counter(hdcp);
                        }
                        break;
                }
                callback_in_ms(0, output);
                set_state_id(hdcp, output, H1_A9_READ_KSV_LIST);
                break;
        case H1_A9_READ_KSV_LIST:
                if (input->bstatus_read != PASS ||
                                input->max_cascade_check != PASS ||
                                input->max_devs_check != PASS ||
                                input->device_count_check != PASS ||
                                input->ksvlist_read != PASS ||
                                input->vp_read != PASS ||
                                input->ksvlist_vp_validation != PASS ||
                                input->encryption != PASS) {
                        /* 1B-06: consider MAX_CASCADE_EXCEEDED a failure */
                        /* 1B-05: consider MAX_DEVS_EXCEEDED a failure */
                        /* 1B-04: consider invalid v' a failure */
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                }
                callback_in_ms(0, output);
                set_state_id(hdcp, output, H1_A45_AUTHENTICATED);
                set_auth_complete(hdcp, output);
                break;
        default:
                status = MOD_HDCP_STATUS_INVALID_STATE;
                fail_and_restart_in_ms(0, &status, output);
                break;
        }

        return status;
}

enum mod_hdcp_status mod_hdcp_hdcp1_dp_transition(struct mod_hdcp *hdcp,
                struct mod_hdcp_event_context *event_ctx,
                struct mod_hdcp_transition_input_hdcp1 *input,
                struct mod_hdcp_output *output)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
        struct mod_hdcp_connection *conn = &hdcp->connection;
        struct mod_hdcp_link_adjustment *adjust = &hdcp->connection.link.adjust;

        switch (current_state(hdcp)) {
        case D1_A0_DETERMINE_RX_HDCP_CAPABLE:
                if (input->bcaps_read != PASS) {
                        /* 1A-04: no authentication on bcaps read failure */
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                } else if (input->hdcp_capable_dp != PASS) {
                        adjust->hdcp1.disable = 1;
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                }
                callback_in_ms(0, output);
                set_state_id(hdcp, output, D1_A1_EXCHANGE_KSVS);
                break;
        case D1_A1_EXCHANGE_KSVS:
                if (input->create_session != PASS) {
                        /* out of sync with psp state */
                        adjust->hdcp1.disable = 1;
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                } else if (input->an_write != PASS ||
                                input->aksv_write != PASS ||
                                input->bksv_read != PASS ||
                                input->bksv_validation != PASS ||
                                input->ainfo_write == FAIL) {
                        /* 1A-05: consider invalid bksv a failure */
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                }
                set_watchdog_in_ms(hdcp, 100, output);
                set_state_id(hdcp, output, D1_A23_WAIT_FOR_R0_PRIME);
                break;
        case D1_A23_WAIT_FOR_R0_PRIME:
                if (input->bstatus_read != PASS) {
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                } else if (input->r0p_available_dp != PASS) {
                        if (event_ctx->event == MOD_HDCP_EVENT_WATCHDOG_TIMEOUT)
                                fail_and_restart_in_ms(0, &status, output);
                        else
                                increment_stay_counter(hdcp);
                        break;
                }
                callback_in_ms(0, output);
                set_state_id(hdcp, output, D1_A2_COMPUTATIONS_A3_VALIDATE_RX_A5_TEST_FOR_REPEATER);
                break;
        case D1_A2_COMPUTATIONS_A3_VALIDATE_RX_A5_TEST_FOR_REPEATER:
                if (input->r0p_read != PASS) {
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                } else if (input->rx_validation != PASS) {
                        if (hdcp->state.stay_count < 2 &&
                                        !hdcp->connection.is_hdcp1_revoked) {
                                /* allow 2 additional retries */
                                callback_in_ms(0, output);
                                increment_stay_counter(hdcp);
                        } else {
                                /*
                                 * 1A-06: consider invalid r0' a failure
                                 * after 3 attempts.
                                 * 1A-08: consider bksv listed in SRM a failure
                                 */
                                /*
                                 * some slow RX will fail rx validation when it is
                                 * not ready. give it more time to react before retry.
                                 */
                                fail_and_restart_in_ms(1000, &status, output);
                        }
                        break;
                } else if ((!conn->is_repeater && input->encryption != PASS) ||
                                (!conn->is_repeater && is_dp_mst_hdcp(hdcp) && input->stream_encryption_dp != PASS)) {
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                } else if (conn->hdcp1_retry_count < conn->link.adjust.hdcp1.min_auth_retries_wa) {
                        fail_and_restart_in_ms(200, &status, output);
                        break;
                }
                if (conn->is_repeater) {
                        set_watchdog_in_ms(hdcp, 5000, output);
                        set_state_id(hdcp, output, D1_A6_WAIT_FOR_READY);
                } else {
                        set_state_id(hdcp, output, D1_A4_AUTHENTICATED);
                        set_auth_complete(hdcp, output);
                }
                break;
        case D1_A4_AUTHENTICATED:
                if (input->link_integrity_check == FAIL ||
                                input->reauth_request_check == FAIL) {
                        /* 1A-07: restart hdcp on a link integrity failure */
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                }
                break;
        case D1_A6_WAIT_FOR_READY:
                if (input->link_integrity_check == FAIL ||
                                input->reauth_request_check == FAIL) {
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                } else if (input->ready_check != PASS) {
                        if (event_ctx->event ==
                                        MOD_HDCP_EVENT_WATCHDOG_TIMEOUT) {
                                /* 1B-04: fail hdcp on ksv list READY timeout */
                                /* prevent black screen in next attempt */
                                adjust->hdcp1.postpone_encryption = 1;
                                fail_and_restart_in_ms(0, &status, output);
                        } else {
                                increment_stay_counter(hdcp);
                        }
                        break;
                }
                callback_in_ms(0, output);
                set_state_id(hdcp, output, D1_A7_READ_KSV_LIST);
                break;
        case D1_A7_READ_KSV_LIST:
                if (input->binfo_read_dp != PASS ||
                                input->max_cascade_check != PASS ||
                                input->max_devs_check != PASS) {
                        /* 1B-06: consider MAX_DEVS_EXCEEDED a failure */
                        /* 1B-07: consider MAX_CASCADE_EXCEEDED a failure */
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                } else if (input->device_count_check != PASS) {
                        /*
                         * some slow dongle doesn't update
                         * device count as soon as downstream is connected.
                         * give it more time to react.
                         */
                        adjust->hdcp1.postpone_encryption = 1;
                        fail_and_restart_in_ms(1000, &status, output);
                        break;
                } else if (input->ksvlist_read != PASS ||
                                input->vp_read != PASS) {
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                } else if (input->ksvlist_vp_validation != PASS) {
                        if (hdcp->state.stay_count < 2 &&
                                        !hdcp->connection.is_hdcp1_revoked) {
                                /* allow 2 additional retries */
                                callback_in_ms(0, output);
                                increment_stay_counter(hdcp);
                        } else {
                                /*
                                 * 1B-05: consider invalid v' a failure
                                 * after 3 attempts.
                                 */
                                fail_and_restart_in_ms(0, &status, output);
                        }
                        break;
                } else if (input->encryption != PASS ||
                                (is_dp_mst_hdcp(hdcp) && input->stream_encryption_dp != PASS)) {
                        fail_and_restart_in_ms(0, &status, output);
                        break;
                }
                set_state_id(hdcp, output, D1_A4_AUTHENTICATED);
                set_auth_complete(hdcp, output);
                break;
        default:
                fail_and_restart_in_ms(0, &status, output);
                break;
        }

        return status;
}