skmhss/google3/g_ec_commands.h

/*
 * Copyright 2024 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef SECURITY_CRYPTA_COMMANDS_CHROMIUMOS_G_EC_COMMANDS_H_
#define SECURITY_CRYPTA_COMMANDS_CHROMIUMOS_G_EC_COMMANDS_H_

#include <stdint.h>

#define G_EC_HOST_REQUEST_VERSION 3
#define G_EC_HOST_RESPONSE_VERSION 3

#define G_EC_CMD_BOARD_SPECIFIC_BASE 0x3E00

/* Given the private host command offset, calculate the true private host
 * command value.
 */
#define G_EC_PRIVATE_HOST_COMMAND_VALUE(command)                               \
    (G_EC_CMD_BOARD_SPECIFIC_BASE + (command))

/* Version 3 request from host */
typedef struct
{
    /* Structure version (=3)
     *
     * EC will return EC_RES_INVALID_HEADER if it receives a header with a
     * version it doesn't know how to parse.
     */
    uint8_t struct_version;

    /* Checksum of request and data; sum of all bytes including checksum should
     * total to 0.
     */
    uint8_t checksum;

    /* Command code */
    uint16_t command;

    /* Command version */
    uint8_t command_version;

    /* Unused byte in current protocol version; set to 0 */
    uint8_t reserved;

    /* Length of data which follows this header */
    uint16_t data_len;
} __attribute__((packed)) g_ec_host_request;

/* Version 3 response from EC */
typedef struct
{
    /* Structure version (=3) */
    uint8_t struct_version;

    /* Checksum of response and data; sum of all bytes including checksum should
     * total to 0.
     */
    uint8_t checksum;

    /* Result code (EC_RES_*) */
    uint16_t result;

    /* Length of data which follows this header */
    uint16_t data_len;

    /* Unused bytes in current protocol version; set to 0 */
    uint16_t reserved;
} __attribute__((packed)) g_ec_host_response;

#endif // SECURITY_CRYPTA_COMMANDS_CHROMIUMOS_G_EC_COMMANDS_H_