drivers/infiniband/hw/hfi1/eprom.c

   1 /*
   2  * Copyright(c) 2015, 2016 Intel Corporation.
   3  *
   4  * This file is provided under a dual BSD/GPLv2 license.  When using or
   5  * redistributing this file, you may do so under either license.
   6  *
   7  * GPL LICENSE SUMMARY
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of version 2 of the GNU General Public License as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * BSD LICENSE
  19  *
  20  * Redistribution and use in source and binary forms, with or without
  21  * modification, are permitted provided that the following conditions
  22  * are met:
  23  *
  24  *  - Redistributions of source code must retain the above copyright
  25  *    notice, this list of conditions and the following disclaimer.
  26  *  - Redistributions in binary form must reproduce the above copyright
  27  *    notice, this list of conditions and the following disclaimer in
  28  *    the documentation and/or other materials provided with the
  29  *    distribution.
  30  *  - Neither the name of Intel Corporation nor the names of its
  31  *    contributors may be used to endorse or promote products derived
  32  *    from this software without specific prior written permission.
  33  *
  34  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  35  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  36  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  37  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  38  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  39  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  40  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  41  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  42  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  43  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  44  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  45  *
  46  */
  47 #include <linux/delay.h>
  48 #include "hfi.h"
  49 #include "common.h"
  50 #include "eprom.h"
  51
  52 /*
  53  * The EPROM is logically divided into three partitions:
  54  *      partition 0: the first 128K, visible from PCI ROM BAR
  55  *      partition 1: 4K config file (sector size)
  56  *      partition 2: the rest
  57  */
  58 #define P0_SIZE (128 * 1024)
  59 #define P1_SIZE   (4 * 1024)
  60 #define P1_START P0_SIZE
  61 #define P2_START (P0_SIZE + P1_SIZE)
  62
  63 /* controller page size, in bytes */
  64 #define EP_PAGE_SIZE 256
  65 #define EP_PAGE_MASK (EP_PAGE_SIZE - 1)
  66 #define EP_PAGE_DWORDS (EP_PAGE_SIZE / sizeof(u32))
  67
  68 /* controller commands */
  69 #define CMD_SHIFT 24
  70 #define CMD_NOP                     (0)
  71 #define CMD_READ_DATA(addr)         ((0x03 << CMD_SHIFT) | addr)
  72 #define CMD_RELEASE_POWERDOWN_NOID  ((0xab << CMD_SHIFT))
  73
  74 /* controller interface speeds */
  75 #define EP_SPEED_FULL 0x2       /* full speed */
  76
  77 /*
  78  * How long to wait for the EPROM to become available, in ms.
  79  * The spec 32 Mb EPROM takes around 40s to erase then write.
  80  * Double it for safety.
  81  */
  82 #define EPROM_TIMEOUT 80000 /* ms */
  83
  84 /*
  85  * Read a 256 byte (64 dword) EPROM page.
  86  * All callers have verified the offset is at a page boundary.
  87  */
  88 static void read_page(struct hfi1_devdata *dd, u32 offset, u32 *result)
  89 {
  90         int i;
  91
  92         write_csr(dd, ASIC_EEP_ADDR_CMD, CMD_READ_DATA(offset));
  93         for (i = 0; i < EP_PAGE_DWORDS; i++)
  94                 result[i] = (u32)read_csr(dd, ASIC_EEP_DATA);
  95         write_csr(dd, ASIC_EEP_ADDR_CMD, CMD_NOP); /* close open page */
  96 }
  97
  98 /*
  99  * Read length bytes starting at offset from the start of the EPROM.
 100  */
 101 static int read_length(struct hfi1_devdata *dd, u32 start, u32 len, void *dest)
 102 {
 103         u32 buffer[EP_PAGE_DWORDS];
 104         u32 end;
 105         u32 start_offset;
 106         u32 read_start;
 107         u32 bytes;
 108
 109         if (len == 0)
 110                 return 0;
 111
 112         end = start + len;
 113
 114         /*
 115          * Make sure the read range is not outside of the controller read
 116          * command address range.  Note that '>' is correct below - the end
 117          * of the range is OK if it stops at the limit, but no higher.
 118          */
 119         if (end > (1 << CMD_SHIFT))
 120                 return -EINVAL;
 121
 122         /* read the first partial page */
 123         start_offset = start & EP_PAGE_MASK;
 124         if (start_offset) {
 125                 /* partial starting page */
 126
 127                 /* align and read the page that contains the start */
 128                 read_start = start & ~EP_PAGE_MASK;
 129                 read_page(dd, read_start, buffer);
 130
 131                 /* the rest of the page is available data */
 132                 bytes = EP_PAGE_SIZE - start_offset;
 133
 134                 if (len <= bytes) {
 135                         /* end is within this page */
 136                         memcpy(dest, (u8 *)buffer + start_offset, len);
 137                         return 0;
 138                 }
 139
 140                 memcpy(dest, (u8 *)buffer + start_offset, bytes);
 141
 142                 start += bytes;
 143                 len -= bytes;
 144                 dest += bytes;
 145         }
 146         /* start is now page aligned */
 147
 148         /* read whole pages */
 149         while (len >= EP_PAGE_SIZE) {
 150                 read_page(dd, start, buffer);
 151                 memcpy(dest, buffer, EP_PAGE_SIZE);
 152
 153                 start += EP_PAGE_SIZE;
 154                 len -= EP_PAGE_SIZE;
 155                 dest += EP_PAGE_SIZE;
 156         }
 157
 158         /* read the last partial page */
 159         if (len) {
 160                 read_page(dd, start, buffer);
 161                 memcpy(dest, buffer, len);
 162         }
 163
 164         return 0;
 165 }
 166
 167 /*
 168  * Initialize the EPROM handler.
 169  */
 170 int eprom_init(struct hfi1_devdata *dd)
 171 {
 172         int ret = 0;
 173
 174         /* only the discrete chip has an EPROM */
 175         if (dd->pcidev->device != PCI_DEVICE_ID_INTEL0)
 176                 return 0;
 177
 178         /*
 179          * It is OK if both HFIs reset the EPROM as long as they don't
 180          * do it at the same time.
 181          */
 182         ret = acquire_chip_resource(dd, CR_EPROM, EPROM_TIMEOUT);
 183         if (ret) {
 184                 dd_dev_err(dd,
 185                            "%s: unable to acquire EPROM resource, no EPROM support\n",
 186                            __func__);
 187                 goto done_asic;
 188         }
 189
 190         /* reset EPROM to be sure it is in a good state */
 191
 192         /* set reset */
 193         write_csr(dd, ASIC_EEP_CTL_STAT, ASIC_EEP_CTL_STAT_EP_RESET_SMASK);
 194         /* clear reset, set speed */
 195         write_csr(dd, ASIC_EEP_CTL_STAT,
 196                   EP_SPEED_FULL << ASIC_EEP_CTL_STAT_RATE_SPI_SHIFT);
 197
 198         /* wake the device with command "release powerdown NoID" */
 199         write_csr(dd, ASIC_EEP_ADDR_CMD, CMD_RELEASE_POWERDOWN_NOID);
 200
 201         dd->eprom_available = true;
 202         release_chip_resource(dd, CR_EPROM);
 203 done_asic:
 204         return ret;
 205 }
 206
 207 /* magic character sequence that trails an image */
 208 #define IMAGE_TRAIL_MAGIC "egamiAPO"
 209
 210 /* EPROM file types */
 211 #define HFI1_EFT_PLATFORM_CONFIG 2
 212
 213 /* segment size - 128 KiB */
 214 #define SEG_SIZE (128 * 1024)
 215
 216 struct hfi1_eprom_footer {
 217         u32 oprom_size;         /* size of the oprom, in bytes */
 218         u16 num_table_entries;
 219         u16 version;            /* version of this footer */
 220         u32 magic;              /* must be last */
 221 };
 222
 223 struct hfi1_eprom_table_entry {
 224         u32 type;               /* file type */
 225         u32 offset;             /* file offset from start of EPROM */
 226         u32 size;               /* file size, in bytes */
 227 };
 228
 229 /*
 230  * Calculate the max number of table entries that will fit within a directory
 231  * buffer of size 'dir_size'.
 232  */
 233 #define MAX_TABLE_ENTRIES(dir_size) \
 234         (((dir_size) - sizeof(struct hfi1_eprom_footer)) / \
 235                 sizeof(struct hfi1_eprom_table_entry))
 236
 237 #define DIRECTORY_SIZE(n) (sizeof(struct hfi1_eprom_footer) + \
 238         (sizeof(struct hfi1_eprom_table_entry) * (n)))
 239
 240 #define MAGIC4(a, b, c, d) ((d) << 24 | (c) << 16 | (b) << 8 | (a))
 241 #define FOOTER_MAGIC MAGIC4('e', 'p', 'r', 'm')
 242 #define FOOTER_VERSION 1
 243
 244 /*
 245  * Read all of partition 1.  The actual file is at the front.  Adjust
 246  * the returned size if a trailing image magic is found.
 247  */
 248 static int read_partition_platform_config(struct hfi1_devdata *dd, void **data,
 249                                           u32 *size)
 250 {
 251         void *buffer;
 252         void *p;
 253         int ret;
 254
 255         buffer = kmalloc(P1_SIZE, GFP_KERNEL);
 256         if (!buffer)
 257                 return -ENOMEM;
 258
 259         ret = read_length(dd, P1_START, P1_SIZE, buffer);
 260         if (ret) {
 261                 kfree(buffer);
 262                 return ret;
 263         }
 264
 265         /* scan for image magic that may trail the actual data */
 266         p = strnstr(buffer, IMAGE_TRAIL_MAGIC, P1_SIZE);
 267         if (!p) {
 268                 kfree(buffer);
 269                 return -ENOENT;
 270         }
 271
 272         *data = buffer;
 273         *size = p - buffer;
 274         return 0;
 275 }
 276
 277 /*
 278  * The segment magic has been checked.  There is a footer and table of
 279  * contents present.
 280  *
 281  * directory is a u32 aligned buffer of size EP_PAGE_SIZE.
 282  */
 283 static int read_segment_platform_config(struct hfi1_devdata *dd,
 284                                         void *directory, void **data, u32 *size)
 285 {
 286         struct hfi1_eprom_footer *footer;
 287         struct hfi1_eprom_table_entry *table;
 288         struct hfi1_eprom_table_entry *entry;
 289         void *buffer = NULL;
 290         void *table_buffer = NULL;
 291         int ret, i;
 292         u32 directory_size;
 293         u32 seg_base, seg_offset;
 294         u32 bytes_available, ncopied, to_copy;
 295
 296         /* the footer is at the end of the directory */
 297         footer = (struct hfi1_eprom_footer *)
 298                         (directory + EP_PAGE_SIZE - sizeof(*footer));
 299
 300         /* make sure the structure version is supported */
 301         if (footer->version != FOOTER_VERSION)
 302                 return -EINVAL;
 303
 304         /* oprom size cannot be larger than a segment */
 305         if (footer->oprom_size >= SEG_SIZE)
 306                 return -EINVAL;
 307
 308         /* the file table must fit in a segment with the oprom */
 309         if (footer->num_table_entries >
 310                         MAX_TABLE_ENTRIES(SEG_SIZE - footer->oprom_size))
 311                 return -EINVAL;
 312
 313         /* find the file table start, which precedes the footer */
 314         directory_size = DIRECTORY_SIZE(footer->num_table_entries);
 315         if (directory_size <= EP_PAGE_SIZE) {
 316                 /* the file table fits into the directory buffer handed in */
 317                 table = (struct hfi1_eprom_table_entry *)
 318                                 (directory + EP_PAGE_SIZE - directory_size);
 319         } else {
 320                 /* need to allocate and read more */
 321                 table_buffer = kmalloc(directory_size, GFP_KERNEL);
 322                 if (!table_buffer)
 323                         return -ENOMEM;
 324                 ret = read_length(dd, SEG_SIZE - directory_size,
 325                                   directory_size, table_buffer);
 326                 if (ret)
 327                         goto done;
 328                 table = table_buffer;
 329         }
 330
 331         /* look for the platform configuration file in the table */
 332         for (entry = NULL, i = 0; i < footer->num_table_entries; i++) {
 333                 if (table[i].type == HFI1_EFT_PLATFORM_CONFIG) {
 334                         entry = &table[i];
 335                         break;
 336                 }
 337         }
 338         if (!entry) {
 339                 ret = -ENOENT;
 340                 goto done;
 341         }
 342
 343         /*
 344          * Sanity check on the configuration file size - it should never
 345          * be larger than 4 KiB.
 346          */
 347         if (entry->size > (4 * 1024)) {
 348                 dd_dev_err(dd, "Bad configuration file size 0x%x\n",
 349                            entry->size);
 350                 ret = -EINVAL;
 351                 goto done;
 352         }
 353
 354         /* check for bogus offset and size that wrap when added together */
 355         if (entry->offset + entry->size < entry->offset) {
 356                 dd_dev_err(dd,
 357                            "Bad configuration file start + size 0x%x+0x%x\n",
 358                            entry->offset, entry->size);
 359                 ret = -EINVAL;
 360                 goto done;
 361         }
 362
 363         /* allocate the buffer to return */
 364         buffer = kmalloc(entry->size, GFP_KERNEL);
 365         if (!buffer) {
 366                 ret = -ENOMEM;
 367                 goto done;
 368         }
 369
 370         /*
 371          * Extract the file by looping over segments until it is fully read.
 372          */
 373         seg_offset = entry->offset % SEG_SIZE;
 374         seg_base = entry->offset - seg_offset;
 375         ncopied = 0;
 376         while (ncopied < entry->size) {
 377                 /* calculate data bytes available in this segment */
 378
 379                 /* start with the bytes from the current offset to the end */
 380                 bytes_available = SEG_SIZE - seg_offset;
 381                 /* subtract off footer and table from segment 0 */
 382                 if (seg_base == 0) {
 383                         /*
 384                          * Sanity check: should not have a starting point
 385                          * at or within the directory.
 386                          */
 387                         if (bytes_available <= directory_size) {
 388                                 dd_dev_err(dd,
 389                                            "Bad configuration file - offset 0x%x within footer+table\n",
 390                                            entry->offset);
 391                                 ret = -EINVAL;
 392                                 goto done;
 393                         }
 394                         bytes_available -= directory_size;
 395                 }
 396
 397                 /* calculate bytes wanted */
 398                 to_copy = entry->size - ncopied;
 399
 400                 /* max out at the available bytes in this segment */
 401                 if (to_copy > bytes_available)
 402                         to_copy = bytes_available;
 403
 404                 /*
 405                  * Read from the EPROM.
 406                  *
 407                  * The sanity check for entry->offset is done in read_length().
 408                  * The EPROM offset is validated against what the hardware
 409                  * addressing supports.  In addition, if the offset is larger
 410                  * than the actual EPROM, it silently wraps.  It will work
 411                  * fine, though the reader may not get what they expected
 412                  * from the EPROM.
 413                  */
 414                 ret = read_length(dd, seg_base + seg_offset, to_copy,
 415                                   buffer + ncopied);
 416                 if (ret)
 417                         goto done;
 418
 419                 ncopied += to_copy;
 420
 421                 /* set up for next segment */
 422                 seg_offset = footer->oprom_size;
 423                 seg_base += SEG_SIZE;
 424         }
 425
 426         /* success */
 427         ret = 0;
 428         *data = buffer;
 429         *size = entry->size;
 430
 431 done:
 432         kfree(table_buffer);
 433         if (ret)
 434                 kfree(buffer);
 435         return ret;
 436 }
 437
 438 /*
 439  * Read the platform configuration file from the EPROM.
 440  *
 441  * On success, an allocated buffer containing the data and its size are
 442  * returned.  It is up to the caller to free this buffer.
 443  *
 444  * Return value:
 445  *   0        - success
 446  *   -ENXIO   - no EPROM is available
 447  *   -EBUSY   - not able to acquire access to the EPROM
 448  *   -ENOENT  - no recognizable file written
 449  *   -ENOMEM  - buffer could not be allocated
 450  *   -EINVAL  - invalid EPROM contentents found
 451  */
 452 int eprom_read_platform_config(struct hfi1_devdata *dd, void **data, u32 *size)
 453 {
 454         u32 directory[EP_PAGE_DWORDS]; /* aligned buffer */
 455         int ret;
 456
 457         if (!dd->eprom_available)
 458                 return -ENXIO;
 459
 460         ret = acquire_chip_resource(dd, CR_EPROM, EPROM_TIMEOUT);
 461         if (ret)
 462                 return -EBUSY;
 463
 464         /* read the last page of the segment for the EPROM format magic */
 465         ret = read_length(dd, SEG_SIZE - EP_PAGE_SIZE, EP_PAGE_SIZE, directory);
 466         if (ret)
 467                 goto done;
 468
 469         /* last dword of the segment contains a magic value */
 470         if (directory[EP_PAGE_DWORDS - 1] == FOOTER_MAGIC) {
 471                 /* segment format */
 472                 ret = read_segment_platform_config(dd, directory, data, size);
 473         } else {
 474                 /* partition format */
 475                 ret = read_partition_platform_config(dd, data, size);
 476         }
 477
 478 done:
 479         release_chip_resource(dd, CR_EPROM);
 480         return ret;
 481 }