1 /****************************************************************************** 2 * 3 * This file is provided under a dual BSD/GPLv2 license. When using or 4 * redistributing this file, you may do so under either license. 5 * 6 * GPL LICENSE SUMMARY 7 * 8 * Copyright(c) 2008 - 2014 Intel Corporation. All rights reserved. 9 * Copyright(c) 2018 Intel Corporation 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of version 2 of the GNU General Public License as 13 * published by the Free Software Foundation. 14 * 15 * This program is distributed in the hope that it will be useful, but 16 * WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 18 * General Public License for more details. 19 * 20 * The full GNU General Public License is included in this distribution 21 * in the file called COPYING. 22 * 23 * Contact Information: 24 * Intel Linux Wireless <linuxwifi@intel.com> 25 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 26 * 27 * BSD LICENSE 28 * 29 * Copyright(c) 2005 - 2014 Intel Corporation. All rights reserved. 30 * Copyright(c) 2018 Intel Corporation 31 * All rights reserved. 32 * 33 * Redistribution and use in source and binary forms, with or without 34 * modification, are permitted provided that the following conditions 35 * are met: 36 * 37 * * Redistributions of source code must retain the above copyright 38 * notice, this list of conditions and the following disclaimer. 39 * * Redistributions in binary form must reproduce the above copyright 40 * notice, this list of conditions and the following disclaimer in 41 * the documentation and/or other materials provided with the 42 * distribution. 43 * * Neither the name Intel Corporation nor the names of its 44 * contributors may be used to endorse or promote products derived 45 * from this software without specific prior written permission. 46 * 47 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 48 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 49 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 50 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 51 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 52 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 53 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 54 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 55 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 56 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 57 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 58 *****************************************************************************/ 59 #include <linux/types.h> 60 #include <linux/slab.h> 61 #include <linux/export.h> 62 63 #include "iwl-drv.h" 64 #include "iwl-debug.h" 65 #include "iwl-eeprom-read.h" 66 #include "iwl-io.h" 67 #include "iwl-prph.h" 68 #include "iwl-csr.h" 69 70 /* 71 * EEPROM access time values: 72 * 73 * Driver initiates EEPROM read by writing byte address << 1 to CSR_EEPROM_REG. 74 * Driver then polls CSR_EEPROM_REG for CSR_EEPROM_REG_READ_VALID_MSK (0x1). 75 * When polling, wait 10 uSec between polling loops, up to a maximum 5000 uSec. 76 * Driver reads 16-bit value from bits 31-16 of CSR_EEPROM_REG. 77 */ 78 #define IWL_EEPROM_ACCESS_TIMEOUT 5000 /* uSec */ 79 80 #define IWL_EEPROM_SEM_TIMEOUT 10 /* microseconds */ 81 #define IWL_EEPROM_SEM_RETRY_LIMIT 1000 /* number of attempts (not time) */ 82 83 84 /* 85 * The device's EEPROM semaphore prevents conflicts between driver and uCode 86 * when accessing the EEPROM; each access is a series of pulses to/from the 87 * EEPROM chip, not a single event, so even reads could conflict if they 88 * weren't arbitrated by the semaphore. 89 */ 90 91 #define EEPROM_SEM_TIMEOUT 10 /* milliseconds */ 92 #define EEPROM_SEM_RETRY_LIMIT 1000 /* number of attempts (not time) */ 93 94 static int iwl_eeprom_acquire_semaphore(struct iwl_trans *trans) 95 { 96 u16 count; 97 int ret; 98 99 for (count = 0; count < EEPROM_SEM_RETRY_LIMIT; count++) { 100 /* Request semaphore */ 101 iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG, 102 CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM); 103 104 /* See if we got it */ 105 ret = iwl_poll_bit(trans, CSR_HW_IF_CONFIG_REG, 106 CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM, 107 CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM, 108 EEPROM_SEM_TIMEOUT); 109 if (ret >= 0) { 110 IWL_DEBUG_EEPROM(trans->dev, 111 "Acquired semaphore after %d tries.\n", 112 count+1); 113 return ret; 114 } 115 } 116 117 return ret; 118 } 119 120 static void iwl_eeprom_release_semaphore(struct iwl_trans *trans) 121 { 122 iwl_clear_bit(trans, CSR_HW_IF_CONFIG_REG, 123 CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM); 124 } 125 126 static int iwl_eeprom_verify_signature(struct iwl_trans *trans, bool nvm_is_otp) 127 { 128 u32 gp = iwl_read32(trans, CSR_EEPROM_GP) & CSR_EEPROM_GP_VALID_MSK; 129 130 IWL_DEBUG_EEPROM(trans->dev, "EEPROM signature=0x%08x\n", gp); 131 132 switch (gp) { 133 case CSR_EEPROM_GP_BAD_SIG_EEP_GOOD_SIG_OTP: 134 if (!nvm_is_otp) { 135 IWL_ERR(trans, "EEPROM with bad signature: 0x%08x\n", 136 gp); 137 return -ENOENT; 138 } 139 return 0; 140 case CSR_EEPROM_GP_GOOD_SIG_EEP_LESS_THAN_4K: 141 case CSR_EEPROM_GP_GOOD_SIG_EEP_MORE_THAN_4K: 142 if (nvm_is_otp) { 143 IWL_ERR(trans, "OTP with bad signature: 0x%08x\n", gp); 144 return -ENOENT; 145 } 146 return 0; 147 case CSR_EEPROM_GP_BAD_SIGNATURE_BOTH_EEP_AND_OTP: 148 default: 149 IWL_ERR(trans, 150 "bad EEPROM/OTP signature, type=%s, EEPROM_GP=0x%08x\n", 151 nvm_is_otp ? "OTP" : "EEPROM", gp); 152 return -ENOENT; 153 } 154 } 155 156 /****************************************************************************** 157 * 158 * OTP related functions 159 * 160 ******************************************************************************/ 161 162 static void iwl_set_otp_access_absolute(struct iwl_trans *trans) 163 { 164 iwl_read32(trans, CSR_OTP_GP_REG); 165 166 iwl_clear_bit(trans, CSR_OTP_GP_REG, 167 CSR_OTP_GP_REG_OTP_ACCESS_MODE); 168 } 169 170 static int iwl_nvm_is_otp(struct iwl_trans *trans) 171 { 172 u32 otpgp; 173 174 /* OTP only valid for CP/PP and after */ 175 switch (trans->hw_rev & CSR_HW_REV_TYPE_MSK) { 176 case CSR_HW_REV_TYPE_NONE: 177 IWL_ERR(trans, "Unknown hardware type\n"); 178 return -EIO; 179 case CSR_HW_REV_TYPE_5300: 180 case CSR_HW_REV_TYPE_5350: 181 case CSR_HW_REV_TYPE_5100: 182 case CSR_HW_REV_TYPE_5150: 183 return 0; 184 default: 185 otpgp = iwl_read32(trans, CSR_OTP_GP_REG); 186 if (otpgp & CSR_OTP_GP_REG_DEVICE_SELECT) 187 return 1; 188 return 0; 189 } 190 } 191 192 static int iwl_init_otp_access(struct iwl_trans *trans) 193 { 194 int ret; 195 196 ret = iwl_finish_nic_init(trans); 197 if (ret) 198 return ret; 199 200 iwl_set_bits_prph(trans, APMG_PS_CTRL_REG, 201 APMG_PS_CTRL_VAL_RESET_REQ); 202 udelay(5); 203 iwl_clear_bits_prph(trans, APMG_PS_CTRL_REG, 204 APMG_PS_CTRL_VAL_RESET_REQ); 205 206 /* 207 * CSR auto clock gate disable bit - 208 * this is only applicable for HW with OTP shadow RAM 209 */ 210 if (trans->cfg->base_params->shadow_ram_support) 211 iwl_set_bit(trans, CSR_DBG_LINK_PWR_MGMT_REG, 212 CSR_RESET_LINK_PWR_MGMT_DISABLED); 213 214 return 0; 215 } 216 217 static int iwl_read_otp_word(struct iwl_trans *trans, u16 addr, 218 __le16 *eeprom_data) 219 { 220 int ret = 0; 221 u32 r; 222 u32 otpgp; 223 224 iwl_write32(trans, CSR_EEPROM_REG, 225 CSR_EEPROM_REG_MSK_ADDR & (addr << 1)); 226 ret = iwl_poll_bit(trans, CSR_EEPROM_REG, 227 CSR_EEPROM_REG_READ_VALID_MSK, 228 CSR_EEPROM_REG_READ_VALID_MSK, 229 IWL_EEPROM_ACCESS_TIMEOUT); 230 if (ret < 0) { 231 IWL_ERR(trans, "Time out reading OTP[%d]\n", addr); 232 return ret; 233 } 234 r = iwl_read32(trans, CSR_EEPROM_REG); 235 /* check for ECC errors: */ 236 otpgp = iwl_read32(trans, CSR_OTP_GP_REG); 237 if (otpgp & CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK) { 238 /* stop in this case */ 239 /* set the uncorrectable OTP ECC bit for acknowledgment */ 240 iwl_set_bit(trans, CSR_OTP_GP_REG, 241 CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK); 242 IWL_ERR(trans, "Uncorrectable OTP ECC error, abort OTP read\n"); 243 return -EINVAL; 244 } 245 if (otpgp & CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK) { 246 /* continue in this case */ 247 /* set the correctable OTP ECC bit for acknowledgment */ 248 iwl_set_bit(trans, CSR_OTP_GP_REG, 249 CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK); 250 IWL_ERR(trans, "Correctable OTP ECC error, continue read\n"); 251 } 252 *eeprom_data = cpu_to_le16(r >> 16); 253 return 0; 254 } 255 256 /* 257 * iwl_is_otp_empty: check for empty OTP 258 */ 259 static bool iwl_is_otp_empty(struct iwl_trans *trans) 260 { 261 u16 next_link_addr = 0; 262 __le16 link_value; 263 bool is_empty = false; 264 265 /* locate the beginning of OTP link list */ 266 if (!iwl_read_otp_word(trans, next_link_addr, &link_value)) { 267 if (!link_value) { 268 IWL_ERR(trans, "OTP is empty\n"); 269 is_empty = true; 270 } 271 } else { 272 IWL_ERR(trans, "Unable to read first block of OTP list.\n"); 273 is_empty = true; 274 } 275 276 return is_empty; 277 } 278 279 280 /* 281 * iwl_find_otp_image: find EEPROM image in OTP 282 * finding the OTP block that contains the EEPROM image. 283 * the last valid block on the link list (the block _before_ the last block) 284 * is the block we should read and used to configure the device. 285 * If all the available OTP blocks are full, the last block will be the block 286 * we should read and used to configure the device. 287 * only perform this operation if shadow RAM is disabled 288 */ 289 static int iwl_find_otp_image(struct iwl_trans *trans, 290 u16 *validblockaddr) 291 { 292 u16 next_link_addr = 0, valid_addr; 293 __le16 link_value = 0; 294 int usedblocks = 0; 295 296 /* set addressing mode to absolute to traverse the link list */ 297 iwl_set_otp_access_absolute(trans); 298 299 /* checking for empty OTP or error */ 300 if (iwl_is_otp_empty(trans)) 301 return -EINVAL; 302 303 /* 304 * start traverse link list 305 * until reach the max number of OTP blocks 306 * different devices have different number of OTP blocks 307 */ 308 do { 309 /* save current valid block address 310 * check for more block on the link list 311 */ 312 valid_addr = next_link_addr; 313 next_link_addr = le16_to_cpu(link_value) * sizeof(u16); 314 IWL_DEBUG_EEPROM(trans->dev, "OTP blocks %d addr 0x%x\n", 315 usedblocks, next_link_addr); 316 if (iwl_read_otp_word(trans, next_link_addr, &link_value)) 317 return -EINVAL; 318 if (!link_value) { 319 /* 320 * reach the end of link list, return success and 321 * set address point to the starting address 322 * of the image 323 */ 324 *validblockaddr = valid_addr; 325 /* skip first 2 bytes (link list pointer) */ 326 *validblockaddr += 2; 327 return 0; 328 } 329 /* more in the link list, continue */ 330 usedblocks++; 331 } while (usedblocks <= trans->cfg->base_params->max_ll_items); 332 333 /* OTP has no valid blocks */ 334 IWL_DEBUG_EEPROM(trans->dev, "OTP has no valid blocks\n"); 335 return -EINVAL; 336 } 337 338 /** 339 * iwl_read_eeprom - read EEPROM contents 340 * 341 * Load the EEPROM contents from adapter and return it 342 * and its size. 343 * 344 * NOTE: This routine uses the non-debug IO access functions. 345 */ 346 int iwl_read_eeprom(struct iwl_trans *trans, u8 **eeprom, size_t *eeprom_size) 347 { 348 __le16 *e; 349 u32 gp = iwl_read32(trans, CSR_EEPROM_GP); 350 int sz; 351 int ret; 352 u16 addr; 353 u16 validblockaddr = 0; 354 u16 cache_addr = 0; 355 int nvm_is_otp; 356 357 if (!eeprom || !eeprom_size) 358 return -EINVAL; 359 360 nvm_is_otp = iwl_nvm_is_otp(trans); 361 if (nvm_is_otp < 0) 362 return nvm_is_otp; 363 364 sz = trans->cfg->base_params->eeprom_size; 365 IWL_DEBUG_EEPROM(trans->dev, "NVM size = %d\n", sz); 366 367 e = kmalloc(sz, GFP_KERNEL); 368 if (!e) 369 return -ENOMEM; 370 371 ret = iwl_eeprom_verify_signature(trans, nvm_is_otp); 372 if (ret < 0) { 373 IWL_ERR(trans, "EEPROM not found, EEPROM_GP=0x%08x\n", gp); 374 goto err_free; 375 } 376 377 /* Make sure driver (instead of uCode) is allowed to read EEPROM */ 378 ret = iwl_eeprom_acquire_semaphore(trans); 379 if (ret < 0) { 380 IWL_ERR(trans, "Failed to acquire EEPROM semaphore.\n"); 381 goto err_free; 382 } 383 384 if (nvm_is_otp) { 385 ret = iwl_init_otp_access(trans); 386 if (ret) { 387 IWL_ERR(trans, "Failed to initialize OTP access.\n"); 388 goto err_unlock; 389 } 390 391 iwl_write32(trans, CSR_EEPROM_GP, 392 iwl_read32(trans, CSR_EEPROM_GP) & 393 ~CSR_EEPROM_GP_IF_OWNER_MSK); 394 395 iwl_set_bit(trans, CSR_OTP_GP_REG, 396 CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK | 397 CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK); 398 /* traversing the linked list if no shadow ram supported */ 399 if (!trans->cfg->base_params->shadow_ram_support) { 400 ret = iwl_find_otp_image(trans, &validblockaddr); 401 if (ret) 402 goto err_unlock; 403 } 404 for (addr = validblockaddr; addr < validblockaddr + sz; 405 addr += sizeof(u16)) { 406 __le16 eeprom_data; 407 408 ret = iwl_read_otp_word(trans, addr, &eeprom_data); 409 if (ret) 410 goto err_unlock; 411 e[cache_addr / 2] = eeprom_data; 412 cache_addr += sizeof(u16); 413 } 414 } else { 415 /* eeprom is an array of 16bit values */ 416 for (addr = 0; addr < sz; addr += sizeof(u16)) { 417 u32 r; 418 419 iwl_write32(trans, CSR_EEPROM_REG, 420 CSR_EEPROM_REG_MSK_ADDR & (addr << 1)); 421 422 ret = iwl_poll_bit(trans, CSR_EEPROM_REG, 423 CSR_EEPROM_REG_READ_VALID_MSK, 424 CSR_EEPROM_REG_READ_VALID_MSK, 425 IWL_EEPROM_ACCESS_TIMEOUT); 426 if (ret < 0) { 427 IWL_ERR(trans, 428 "Time out reading EEPROM[%d]\n", addr); 429 goto err_unlock; 430 } 431 r = iwl_read32(trans, CSR_EEPROM_REG); 432 e[addr / 2] = cpu_to_le16(r >> 16); 433 } 434 } 435 436 IWL_DEBUG_EEPROM(trans->dev, "NVM Type: %s\n", 437 nvm_is_otp ? "OTP" : "EEPROM"); 438 439 iwl_eeprom_release_semaphore(trans); 440 441 *eeprom_size = sz; 442 *eeprom = (u8 *)e; 443 return 0; 444 445 err_unlock: 446 iwl_eeprom_release_semaphore(trans); 447 err_free: 448 kfree(e); 449 450 return ret; 451 } 452 IWL_EXPORT_SYMBOL(iwl_read_eeprom); 453