Hung-Te Lin | 6bfbb33 | 2013-04-15 18:27:24 +0800 | [diff] [blame] | 1 | /* |
| 2 | * This file is part of the coreboot project. |
| 3 | * |
| 4 | * Copyright (C) 2013 Google Inc. All rights reserved. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; version 2 of the License |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
Hung-Te Lin | 6bfbb33 | 2013-04-15 18:27:24 +0800 | [diff] [blame] | 14 | */ |
| 15 | |
| 16 | #include <arch/io.h> |
| 17 | #include <console/console.h> |
| 18 | #include <delay.h> |
| 19 | #include <device/i2c.h> |
| 20 | #include <stdint.h> |
| 21 | #include <string.h> |
Edward O'Callaghan | b57fef9 | 2014-06-17 20:13:08 +1000 | [diff] [blame] | 22 | |
Hung-Te Lin | 6bfbb33 | 2013-04-15 18:27:24 +0800 | [diff] [blame] | 23 | #include "ec.h" |
| 24 | #include "ec_commands.h" |
| 25 | |
Aaron Durbin | aee78f0 | 2014-08-06 14:38:52 -0500 | [diff] [blame] | 26 | #if IS_ENABLED(CONFIG_EC_GOOGLE_CHROMEEC_I2C_PROTO3) |
| 27 | |
| 28 | #define PROTO3_FRAMING_BYTES sizeof(uint32_t) |
| 29 | /* Just use the LPC host packet size to size the buffer. */ |
| 30 | #define PROTO3_MAX_PACKET_SIZE 268 |
| 31 | |
| 32 | struct proto3_i2c_buf { |
| 33 | uint8_t framing_bytes[PROTO3_FRAMING_BYTES]; |
| 34 | uint8_t data[PROTO3_MAX_PACKET_SIZE]; |
| 35 | } __attribute__((aligned(sizeof(uint32_t)))); |
| 36 | |
| 37 | static struct proto3_i2c_buf req_buf; |
| 38 | static struct proto3_i2c_buf resp_buf; |
| 39 | |
| 40 | enum { |
| 41 | CMD_INDEX, |
| 42 | RESP_INDEX, |
| 43 | SEGS_PER_CMD, |
| 44 | }; |
| 45 | |
| 46 | struct i2c_ec { |
| 47 | int bus; |
| 48 | struct i2c_seg segs[SEGS_PER_CMD]; |
| 49 | }; |
| 50 | |
| 51 | static struct i2c_ec ec_dev = { |
| 52 | .bus = CONFIG_EC_GOOGLE_CHROMEEC_I2C_BUS, |
| 53 | .segs[CMD_INDEX] = { |
| 54 | .read = 0, |
| 55 | .chip = CONFIG_EC_GOOGLE_CHROMEEC_I2C_CHIP, |
| 56 | /* Framing byte to be transferred prior to request. */ |
| 57 | .buf = &req_buf.framing_bytes[3], |
| 58 | }, |
| 59 | .segs[RESP_INDEX] = { |
| 60 | .read = 1, |
| 61 | .chip = CONFIG_EC_GOOGLE_CHROMEEC_I2C_CHIP, |
| 62 | /* return code and total length before full response. */ |
| 63 | .buf = &resp_buf.framing_bytes[2], |
| 64 | }, |
| 65 | }; |
| 66 | |
| 67 | void *crosec_get_buffer(size_t size, int req) |
| 68 | { |
| 69 | struct proto3_i2c_buf *ib; |
| 70 | |
| 71 | if (size > PROTO3_MAX_PACKET_SIZE) { |
| 72 | printk(BIOS_DEBUG, "Proto v3 buffer request too large: %zu!\n", |
| 73 | size); |
| 74 | return NULL; |
| 75 | } |
| 76 | |
| 77 | if (req) |
| 78 | ib = &req_buf; |
| 79 | else |
| 80 | ib = &resp_buf; |
| 81 | |
| 82 | return &ib->data[0]; |
| 83 | } |
| 84 | |
| 85 | static int crosec_i2c_io(size_t req_size, size_t resp_size, void *context) |
| 86 | { |
| 87 | struct i2c_ec *ec = context; |
| 88 | uint8_t ret_code; |
| 89 | size_t resp_len; |
| 90 | |
| 91 | if (req_size > PROTO3_MAX_PACKET_SIZE || |
| 92 | resp_size > PROTO3_MAX_PACKET_SIZE) |
| 93 | return -1; |
| 94 | |
| 95 | /* Place the framing byte and set size accordingly. */ |
| 96 | ec->segs[CMD_INDEX].len = req_size + 1; |
| 97 | ec->segs[CMD_INDEX].buf[0] = EC_COMMAND_PROTOCOL_3; |
| 98 | /* Return code and length returned prior to packet data. */ |
| 99 | ec->segs[RESP_INDEX].len = resp_size + 2; |
| 100 | |
| 101 | if (i2c_transfer(ec->bus, ec->segs, ARRAY_SIZE(ec->segs)) != 0) { |
| 102 | printk(BIOS_ERR, "%s: Cannot complete read from i2c-%d:%#x\n", |
| 103 | __func__, ec->bus, ec->segs[0].chip); |
| 104 | return -1; |
| 105 | } |
| 106 | |
| 107 | ret_code = ec->segs[RESP_INDEX].buf[0]; |
| 108 | resp_len = ec->segs[RESP_INDEX].buf[1]; |
| 109 | |
| 110 | if (ret_code != 0) { |
| 111 | printk(BIOS_ERR, "EC command returned 0x%x\n", ret_code); |
| 112 | return -1; |
| 113 | } |
| 114 | |
| 115 | if (resp_len > resp_size) { |
| 116 | printk(BIOS_ERR, "Response length mismatch %zu vs %zu\n", |
| 117 | resp_len, resp_size); |
| 118 | return -1; |
| 119 | } |
| 120 | |
| 121 | return 0; |
| 122 | } |
| 123 | |
| 124 | int google_chromeec_command(struct chromeec_command *cec_command) |
| 125 | { |
| 126 | return crosec_command_proto(cec_command, crosec_i2c_io, &ec_dev); |
| 127 | } |
| 128 | |
| 129 | #else /* CONFIG_EC_GOOGLE_CHROMEEC_I2C_PROTO3 */ |
| 130 | |
Hung-Te Lin | 6bfbb33 | 2013-04-15 18:27:24 +0800 | [diff] [blame] | 131 | /* Command (host->device) format for I2C: |
| 132 | * uint8_t version, cmd, len, data[len], checksum; |
| 133 | * |
| 134 | * Response (device->host) format for I2C: |
| 135 | * uint8_t response, len, data[len], checksum; |
| 136 | * |
| 137 | * Note the location of checksum is different from LPC protocol. |
| 138 | * |
| 139 | * The length is 8 bit so maximum data size is 0xff. |
| 140 | * Any I2C command should fit in 0xff + 4 bytes, and max response length |
| 141 | * is 0xff + 3 bytes. |
| 142 | */ |
| 143 | #define MAX_I2C_DATA_SIZE (0xff) |
| 144 | |
| 145 | typedef struct { |
| 146 | uint8_t version; |
| 147 | uint8_t command; |
| 148 | uint8_t length; |
| 149 | uint8_t data[MAX_I2C_DATA_SIZE + 1]; |
| 150 | } EcCommandI2c; |
| 151 | |
| 152 | typedef struct { |
| 153 | uint8_t response; |
| 154 | uint8_t length; |
| 155 | uint8_t data[MAX_I2C_DATA_SIZE + 1]; |
| 156 | } EcResponseI2c; |
| 157 | |
| 158 | static inline void i2c_dump(int bus, int chip, const uint8_t *data, size_t size) |
| 159 | { |
| 160 | #ifdef TRACE_CHROMEEC |
| 161 | printk(BIOS_INFO, "i2c: bus=%d, chip=%#x, size=%d, data: ", bus, chip, |
| 162 | size); |
| 163 | while (size-- > 0) { |
| 164 | printk(BIOS_INFO, "%02X ", *data++); |
| 165 | } |
| 166 | printk(BIOS_INFO, "\n"); |
| 167 | #endif |
| 168 | } |
| 169 | |
| 170 | static int ec_verify_checksum(const EcResponseI2c *resp) |
| 171 | { |
| 172 | size_t size = sizeof(*resp) - sizeof(resp->data) + resp->length; |
| 173 | uint8_t calculated = google_chromeec_calc_checksum( |
| 174 | (const uint8_t *)resp, size); |
| 175 | uint8_t received = resp->data[resp->length]; |
| 176 | if (calculated != received) { |
| 177 | printk(BIOS_ERR, "%s: Unmatch (rx: %#02x, calc: %#02x)\n", |
| 178 | __func__, received, calculated); |
| 179 | return 0; |
| 180 | } |
| 181 | return 1; |
| 182 | } |
| 183 | |
| 184 | static void ec_fill_checksum(EcCommandI2c *cmd) |
| 185 | { |
| 186 | size_t size = sizeof(*cmd) - sizeof(cmd->data) + cmd->length; |
| 187 | cmd->data[cmd->length] = google_chromeec_calc_checksum( |
| 188 | (const uint8_t *)cmd, size); |
| 189 | } |
| 190 | |
| 191 | int google_chromeec_command(struct chromeec_command *cec_command) |
| 192 | { |
| 193 | EcCommandI2c cmd; |
| 194 | EcResponseI2c resp; |
| 195 | int bus = CONFIG_EC_GOOGLE_CHROMEEC_I2C_BUS; |
| 196 | int chip = CONFIG_EC_GOOGLE_CHROMEEC_I2C_CHIP; |
| 197 | size_t size_i2c_cmd = (sizeof(cmd) - sizeof(cmd.data) + |
| 198 | cec_command->cmd_size_in + 1), |
| 199 | size_i2c_resp = (sizeof(resp) - sizeof(resp.data) + |
| 200 | cec_command->cmd_size_out + 1); |
| 201 | |
| 202 | if (cec_command->cmd_size_in > MAX_I2C_DATA_SIZE || |
| 203 | cec_command->cmd_size_out > MAX_I2C_DATA_SIZE) { |
| 204 | printk(BIOS_ERR, "%s: Command data size too large (%d,%d)\n", |
| 205 | __func__, cec_command->cmd_size_in, |
| 206 | cec_command->cmd_size_out); |
| 207 | cec_command->cmd_code = EC_RES_INVALID_PARAM; |
| 208 | return 1; |
| 209 | } |
| 210 | |
| 211 | /* Construct command. */ |
| 212 | cmd.version = EC_CMD_VERSION0 + cec_command->cmd_version; |
| 213 | cmd.command = cec_command->cmd_code; |
| 214 | cmd.length = cec_command->cmd_size_in; |
| 215 | memcpy(cmd.data, cec_command->cmd_data_in, cmd.length); |
| 216 | ec_fill_checksum(&cmd); |
| 217 | |
| 218 | /* Start I2C communication */ |
| 219 | i2c_dump(bus, chip, (const uint8_t *)&cmd, size_i2c_cmd); |
Gabe Black | cdb61a6 | 2014-04-07 18:45:14 -0700 | [diff] [blame] | 220 | if (i2c_write_raw(bus, chip, (uint8_t *)&cmd, size_i2c_cmd) != 0) { |
Hung-Te Lin | 6bfbb33 | 2013-04-15 18:27:24 +0800 | [diff] [blame] | 221 | printk(BIOS_ERR, "%s: Cannot complete write to i2c-%d:%#x\n", |
| 222 | __func__, bus, chip); |
| 223 | cec_command->cmd_code = EC_RES_ERROR; |
| 224 | return 1; |
| 225 | } |
Gabe Black | cdb61a6 | 2014-04-07 18:45:14 -0700 | [diff] [blame] | 226 | if (i2c_read_raw(bus, chip, (uint8_t *)&resp, size_i2c_resp) != 0) { |
Hung-Te Lin | 6bfbb33 | 2013-04-15 18:27:24 +0800 | [diff] [blame] | 227 | printk(BIOS_ERR, "%s: Cannot complete read from i2c-%d:%#x\n", |
| 228 | __func__, bus, chip); |
| 229 | cec_command->cmd_code = EC_RES_ERROR; |
| 230 | return 1; |
| 231 | } |
| 232 | |
| 233 | /* Verify and return response */ |
| 234 | cec_command->cmd_code = resp.response; |
| 235 | if (resp.response != EC_RES_SUCCESS) { |
| 236 | printk(BIOS_DEBUG, "%s: Received bad result code %d\n", |
| 237 | __func__, (int)resp.response); |
| 238 | return 1; |
| 239 | } |
| 240 | if (resp.length > cec_command->cmd_size_out) { |
| 241 | printk(BIOS_ERR, "%s: Received len %#02x too large\n", |
| 242 | __func__, (int)resp.length); |
| 243 | cec_command->cmd_code = EC_RES_INVALID_RESPONSE; |
| 244 | return 1; |
| 245 | } |
| 246 | if (!ec_verify_checksum(&resp)) { |
| 247 | cec_command->cmd_code = EC_RES_INVALID_CHECKSUM; |
| 248 | return 1; |
| 249 | } |
| 250 | cec_command->cmd_size_out = resp.length; |
| 251 | memcpy(cec_command->cmd_data_out, resp.data, resp.length); |
| 252 | return 0; |
| 253 | } |
| 254 | |
Aaron Durbin | aee78f0 | 2014-08-06 14:38:52 -0500 | [diff] [blame] | 255 | #endif /* CONFIG_EC_GOOGLE_CHROMEEC_I2C_PROTO3 */ |
| 256 | |
Hung-Te Lin | 6bfbb33 | 2013-04-15 18:27:24 +0800 | [diff] [blame] | 257 | #ifndef __PRE_RAM__ |
| 258 | u8 google_chromeec_get_event(void) |
| 259 | { |
| 260 | printk(BIOS_ERR, "%s: Not supported.\n", __func__); |
| 261 | return 0; |
| 262 | } |
| 263 | #endif |