drivers/fpga/altera-cvp.c

   1 /*
   2  * FPGA Manager Driver for Altera Arria/Cyclone/Stratix CvP
   3  *
   4  * Copyright (C) 2017 DENX Software Engineering
   5  *
   6  * Anatolij Gustschin <agust@denx.de>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; version 2 of the License.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU General Public License for more details.
  16  *
  17  * Manage Altera FPGA firmware using PCIe CvP.
  18  * Firmware must be in binary "rbf" format.
  19  */
  20
  21 #include <linux/delay.h>
  22 #include <linux/device.h>
  23 #include <linux/fpga/fpga-mgr.h>
  24 #include <linux/module.h>
  25 #include <linux/pci.h>
  26 #include <linux/sizes.h>
  27
  28 #define CVP_BAR         0       /* BAR used for data transfer in memory mode */
  29 #define CVP_DUMMY_WR    244     /* dummy writes to clear CvP state machine */
  30 #define TIMEOUT_US      2000    /* CVP STATUS timeout for USERMODE polling */
  31
  32 /* Vendor Specific Extended Capability Registers */
  33 #define VSE_PCIE_EXT_CAP_ID             0x200
  34 #define VSE_PCIE_EXT_CAP_ID_VAL         0x000b  /* 16bit */
  35
  36 #define VSE_CVP_STATUS                  0x21c   /* 32bit */
  37 #define VSE_CVP_STATUS_CFG_RDY          BIT(18) /* CVP_CONFIG_READY */
  38 #define VSE_CVP_STATUS_CFG_ERR          BIT(19) /* CVP_CONFIG_ERROR */
  39 #define VSE_CVP_STATUS_CVP_EN           BIT(20) /* ctrl block is enabling CVP */
  40 #define VSE_CVP_STATUS_USERMODE         BIT(21) /* USERMODE */
  41 #define VSE_CVP_STATUS_CFG_DONE         BIT(23) /* CVP_CONFIG_DONE */
  42 #define VSE_CVP_STATUS_PLD_CLK_IN_USE   BIT(24) /* PLD_CLK_IN_USE */
  43
  44 #define VSE_CVP_MODE_CTRL               0x220   /* 32bit */
  45 #define VSE_CVP_MODE_CTRL_CVP_MODE      BIT(0)  /* CVP (1) or normal mode (0) */
  46 #define VSE_CVP_MODE_CTRL_HIP_CLK_SEL   BIT(1) /* PMA (1) or fabric clock (0) */
  47 #define VSE_CVP_MODE_CTRL_NUMCLKS_OFF   8       /* NUMCLKS bits offset */
  48 #define VSE_CVP_MODE_CTRL_NUMCLKS_MASK  GENMASK(15, 8)
  49
  50 #define VSE_CVP_DATA                    0x228   /* 32bit */
  51 #define VSE_CVP_PROG_CTRL               0x22c   /* 32bit */
  52 #define VSE_CVP_PROG_CTRL_CONFIG        BIT(0)
  53 #define VSE_CVP_PROG_CTRL_START_XFER    BIT(1)
  54
  55 #define VSE_UNCOR_ERR_STATUS            0x234   /* 32bit */
  56 #define VSE_UNCOR_ERR_CVP_CFG_ERR       BIT(5)  /* CVP_CONFIG_ERROR_LATCHED */
  57
  58 #define DRV_NAME                "altera-cvp"
  59 #define ALTERA_CVP_MGR_NAME     "Altera CvP FPGA Manager"
  60
  61 /* Optional CvP config error status check for debugging */
  62 static bool altera_cvp_chkcfg;
  63
  64 struct altera_cvp_conf {
  65         struct fpga_manager     *mgr;
  66         struct pci_dev          *pci_dev;
  67         void __iomem            *map;
  68         void                    (*write_data)(struct altera_cvp_conf *, u32);
  69         char                    mgr_name[64];
  70         u8                      numclks;
  71 };
  72
  73 static enum fpga_mgr_states altera_cvp_state(struct fpga_manager *mgr)
  74 {
  75         struct altera_cvp_conf *conf = mgr->priv;
  76         u32 status;
  77
  78         pci_read_config_dword(conf->pci_dev, VSE_CVP_STATUS, &status);
  79
  80         if (status & VSE_CVP_STATUS_CFG_DONE)
  81                 return FPGA_MGR_STATE_OPERATING;
  82
  83         if (status & VSE_CVP_STATUS_CVP_EN)
  84                 return FPGA_MGR_STATE_POWER_UP;
  85
  86         return FPGA_MGR_STATE_UNKNOWN;
  87 }
  88
  89 static void altera_cvp_write_data_iomem(struct altera_cvp_conf *conf, u32 val)
  90 {
  91         writel(val, conf->map);
  92 }
  93
  94 static void altera_cvp_write_data_config(struct altera_cvp_conf *conf, u32 val)
  95 {
  96         pci_write_config_dword(conf->pci_dev, VSE_CVP_DATA, val);
  97 }
  98
  99 /* switches between CvP clock and internal clock */
 100 static void altera_cvp_dummy_write(struct altera_cvp_conf *conf)
 101 {
 102         unsigned int i;
 103         u32 val;
 104
 105         /* set 1 CVP clock cycle for every CVP Data Register Write */
 106         pci_read_config_dword(conf->pci_dev, VSE_CVP_MODE_CTRL, &val);
 107         val &= ~VSE_CVP_MODE_CTRL_NUMCLKS_MASK;
 108         val |= 1 << VSE_CVP_MODE_CTRL_NUMCLKS_OFF;
 109         pci_write_config_dword(conf->pci_dev, VSE_CVP_MODE_CTRL, val);
 110
 111         for (i = 0; i < CVP_DUMMY_WR; i++)
 112                 conf->write_data(conf, 0); /* dummy data, could be any value */
 113 }
 114
 115 static int altera_cvp_wait_status(struct altera_cvp_conf *conf, u32 status_mask,
 116                                   u32 status_val, int timeout_us)
 117 {
 118         unsigned int retries;
 119         u32 val;
 120
 121         retries = timeout_us / 10;
 122         if (timeout_us % 10)
 123                 retries++;
 124
 125         do {
 126                 pci_read_config_dword(conf->pci_dev, VSE_CVP_STATUS, &val);
 127                 if ((val & status_mask) == status_val)
 128                         return 0;
 129
 130                 /* use small usleep value to re-check and break early */
 131                 usleep_range(10, 11);
 132         } while (--retries);
 133
 134         return -ETIMEDOUT;
 135 }
 136
 137 static int altera_cvp_teardown(struct fpga_manager *mgr,
 138                                struct fpga_image_info *info)
 139 {
 140         struct altera_cvp_conf *conf = mgr->priv;
 141         struct pci_dev *pdev = conf->pci_dev;
 142         int ret;
 143         u32 val;
 144
 145         /* STEP 12 - reset START_XFER bit */
 146         pci_read_config_dword(pdev, VSE_CVP_PROG_CTRL, &val);
 147         val &= ~VSE_CVP_PROG_CTRL_START_XFER;
 148         pci_write_config_dword(pdev, VSE_CVP_PROG_CTRL, val);
 149
 150         /* STEP 13 - reset CVP_CONFIG bit */
 151         val &= ~VSE_CVP_PROG_CTRL_CONFIG;
 152         pci_write_config_dword(pdev, VSE_CVP_PROG_CTRL, val);
 153
 154         /*
 155          * STEP 14
 156          * - set CVP_NUMCLKS to 1 and then issue CVP_DUMMY_WR dummy
 157          *   writes to the HIP
 158          */
 159         altera_cvp_dummy_write(conf); /* from CVP clock to internal clock */
 160
 161         /* STEP 15 - poll CVP_CONFIG_READY bit for 0 with 10us timeout */
 162         ret = altera_cvp_wait_status(conf, VSE_CVP_STATUS_CFG_RDY, 0, 10);
 163         if (ret)
 164                 dev_err(&mgr->dev, "CFG_RDY == 0 timeout\n");
 165
 166         return ret;
 167 }
 168
 169 static int altera_cvp_write_init(struct fpga_manager *mgr,
 170                                  struct fpga_image_info *info,
 171                                  const char *buf, size_t count)
 172 {
 173         struct altera_cvp_conf *conf = mgr->priv;
 174         struct pci_dev *pdev = conf->pci_dev;
 175         u32 iflags, val;
 176         int ret;
 177
 178         iflags = info ? info->flags : 0;
 179
 180         if (iflags & FPGA_MGR_PARTIAL_RECONFIG) {
 181                 dev_err(&mgr->dev, "Partial reconfiguration not supported.\n");
 182                 return -EINVAL;
 183         }
 184
 185         /* Determine allowed clock to data ratio */
 186         if (iflags & FPGA_MGR_COMPRESSED_BITSTREAM)
 187                 conf->numclks = 8; /* ratio for all compressed images */
 188         else if (iflags & FPGA_MGR_ENCRYPTED_BITSTREAM)
 189                 conf->numclks = 4; /* for uncompressed and encrypted images */
 190         else
 191                 conf->numclks = 1; /* for uncompressed and unencrypted images */
 192
 193         /* STEP 1 - read CVP status and check CVP_EN flag */
 194         pci_read_config_dword(pdev, VSE_CVP_STATUS, &val);
 195         if (!(val & VSE_CVP_STATUS_CVP_EN)) {
 196                 dev_err(&mgr->dev, "CVP mode off: 0x%04x\n", val);
 197                 return -ENODEV;
 198         }
 199
 200         if (val & VSE_CVP_STATUS_CFG_RDY) {
 201                 dev_warn(&mgr->dev, "CvP already started, teardown first\n");
 202                 ret = altera_cvp_teardown(mgr, info);
 203                 if (ret)
 204                         return ret;
 205         }
 206
 207         /*
 208          * STEP 2
 209          * - set HIP_CLK_SEL and CVP_MODE (must be set in the order mentioned)
 210          */
 211         /* switch from fabric to PMA clock */
 212         pci_read_config_dword(pdev, VSE_CVP_MODE_CTRL, &val);
 213         val |= VSE_CVP_MODE_CTRL_HIP_CLK_SEL;
 214         pci_write_config_dword(pdev, VSE_CVP_MODE_CTRL, val);
 215
 216         /* set CVP mode */
 217         pci_read_config_dword(pdev, VSE_CVP_MODE_CTRL, &val);
 218         val |= VSE_CVP_MODE_CTRL_CVP_MODE;
 219         pci_write_config_dword(pdev, VSE_CVP_MODE_CTRL, val);
 220
 221         /*
 222          * STEP 3
 223          * - set CVP_NUMCLKS to 1 and issue CVP_DUMMY_WR dummy writes to the HIP
 224          */
 225         altera_cvp_dummy_write(conf);
 226
 227         /* STEP 4 - set CVP_CONFIG bit */
 228         pci_read_config_dword(pdev, VSE_CVP_PROG_CTRL, &val);
 229         /* request control block to begin transfer using CVP */
 230         val |= VSE_CVP_PROG_CTRL_CONFIG;
 231         pci_write_config_dword(pdev, VSE_CVP_PROG_CTRL, val);
 232
 233         /* STEP 5 - poll CVP_CONFIG READY for 1 with 10us timeout */
 234         ret = altera_cvp_wait_status(conf, VSE_CVP_STATUS_CFG_RDY,
 235                                      VSE_CVP_STATUS_CFG_RDY, 10);
 236         if (ret) {
 237                 dev_warn(&mgr->dev, "CFG_RDY == 1 timeout\n");
 238                 return ret;
 239         }
 240
 241         /*
 242          * STEP 6
 243          * - set CVP_NUMCLKS to 1 and issue CVP_DUMMY_WR dummy writes to the HIP
 244          */
 245         altera_cvp_dummy_write(conf);
 246
 247         /* STEP 7 - set START_XFER */
 248         pci_read_config_dword(pdev, VSE_CVP_PROG_CTRL, &val);
 249         val |= VSE_CVP_PROG_CTRL_START_XFER;
 250         pci_write_config_dword(pdev, VSE_CVP_PROG_CTRL, val);
 251
 252         /* STEP 8 - start transfer (set CVP_NUMCLKS for bitstream) */
 253         pci_read_config_dword(pdev, VSE_CVP_MODE_CTRL, &val);
 254         val &= ~VSE_CVP_MODE_CTRL_NUMCLKS_MASK;
 255         val |= conf->numclks << VSE_CVP_MODE_CTRL_NUMCLKS_OFF;
 256         pci_write_config_dword(pdev, VSE_CVP_MODE_CTRL, val);
 257
 258         return 0;
 259 }
 260
 261 static inline int altera_cvp_chk_error(struct fpga_manager *mgr, size_t bytes)
 262 {
 263         struct altera_cvp_conf *conf = mgr->priv;
 264         u32 val;
 265
 266         /* STEP 10 (optional) - check CVP_CONFIG_ERROR flag */
 267         pci_read_config_dword(conf->pci_dev, VSE_CVP_STATUS, &val);
 268         if (val & VSE_CVP_STATUS_CFG_ERR) {
 269                 dev_err(&mgr->dev, "CVP_CONFIG_ERROR after %zu bytes!\n",
 270                         bytes);
 271                 return -EPROTO;
 272         }
 273         return 0;
 274 }
 275
 276 static int altera_cvp_write(struct fpga_manager *mgr, const char *buf,
 277                             size_t count)
 278 {
 279         struct altera_cvp_conf *conf = mgr->priv;
 280         const u32 *data;
 281         size_t done, remaining;
 282         int status = 0;
 283         u32 mask;
 284
 285         /* STEP 9 - write 32-bit data from RBF file to CVP data register */
 286         data = (u32 *)buf;
 287         remaining = count;
 288         done = 0;
 289
 290         while (remaining >= 4) {
 291                 conf->write_data(conf, *data++);
 292                 done += 4;
 293                 remaining -= 4;
 294
 295                 /*
 296                  * STEP 10 (optional) and STEP 11
 297                  * - check error flag
 298                  * - loop until data transfer completed
 299                  * Config images can be huge (more than 40 MiB), so
 300                  * only check after a new 4k data block has been written.
 301                  * This reduces the number of checks and speeds up the
 302                  * configuration process.
 303                  */
 304                 if (altera_cvp_chkcfg && !(done % SZ_4K)) {
 305                         status = altera_cvp_chk_error(mgr, done);
 306                         if (status < 0)
 307                                 return status;
 308                 }
 309         }
 310
 311         /* write up to 3 trailing bytes, if any */
 312         mask = BIT(remaining * 8) - 1;
 313         if (mask)
 314                 conf->write_data(conf, *data & mask);
 315
 316         if (altera_cvp_chkcfg)
 317                 status = altera_cvp_chk_error(mgr, count);
 318
 319         return status;
 320 }
 321
 322 static int altera_cvp_write_complete(struct fpga_manager *mgr,
 323                                      struct fpga_image_info *info)
 324 {
 325         struct altera_cvp_conf *conf = mgr->priv;
 326         struct pci_dev *pdev = conf->pci_dev;
 327         int ret;
 328         u32 mask;
 329         u32 val;
 330
 331         ret = altera_cvp_teardown(mgr, info);
 332         if (ret)
 333                 return ret;
 334
 335         /* STEP 16 - check CVP_CONFIG_ERROR_LATCHED bit */
 336         pci_read_config_dword(pdev, VSE_UNCOR_ERR_STATUS, &val);
 337         if (val & VSE_UNCOR_ERR_CVP_CFG_ERR) {
 338                 dev_err(&mgr->dev, "detected CVP_CONFIG_ERROR_LATCHED!\n");
 339                 return -EPROTO;
 340         }
 341
 342         /* STEP 17 - reset CVP_MODE and HIP_CLK_SEL bit */
 343         pci_read_config_dword(pdev, VSE_CVP_MODE_CTRL, &val);
 344         val &= ~VSE_CVP_MODE_CTRL_HIP_CLK_SEL;
 345         val &= ~VSE_CVP_MODE_CTRL_CVP_MODE;
 346         pci_write_config_dword(pdev, VSE_CVP_MODE_CTRL, val);
 347
 348         /* STEP 18 - poll PLD_CLK_IN_USE and USER_MODE bits */
 349         mask = VSE_CVP_STATUS_PLD_CLK_IN_USE | VSE_CVP_STATUS_USERMODE;
 350         ret = altera_cvp_wait_status(conf, mask, mask, TIMEOUT_US);
 351         if (ret)
 352                 dev_err(&mgr->dev, "PLD_CLK_IN_USE|USERMODE timeout\n");
 353
 354         return ret;
 355 }
 356
 357 static const struct fpga_manager_ops altera_cvp_ops = {
 358         .state          = altera_cvp_state,
 359         .write_init     = altera_cvp_write_init,
 360         .write          = altera_cvp_write,
 361         .write_complete = altera_cvp_write_complete,
 362 };
 363
 364 static ssize_t chkcfg_show(struct device_driver *dev, char *buf)
 365 {
 366         return snprintf(buf, 3, "%d\n", altera_cvp_chkcfg);
 367 }
 368
 369 static ssize_t chkcfg_store(struct device_driver *drv, const char *buf,
 370                             size_t count)
 371 {
 372         int ret;
 373
 374         ret = kstrtobool(buf, &altera_cvp_chkcfg);
 375         if (ret)
 376                 return ret;
 377
 378         return count;
 379 }
 380
 381 static DRIVER_ATTR_RW(chkcfg);
 382
 383 static int altera_cvp_probe(struct pci_dev *pdev,
 384                             const struct pci_device_id *dev_id);
 385 static void altera_cvp_remove(struct pci_dev *pdev);
 386
 387 static struct pci_device_id altera_cvp_id_tbl[] = {
 388         { PCI_VDEVICE(ALTERA, PCI_ANY_ID) },
 389         { }
 390 };
 391 MODULE_DEVICE_TABLE(pci, altera_cvp_id_tbl);
 392
 393 static struct pci_driver altera_cvp_driver = {
 394         .name   = DRV_NAME,
 395         .id_table = altera_cvp_id_tbl,
 396         .probe  = altera_cvp_probe,
 397         .remove = altera_cvp_remove,
 398 };
 399
 400 static int altera_cvp_probe(struct pci_dev *pdev,
 401                             const struct pci_device_id *dev_id)
 402 {
 403         struct altera_cvp_conf *conf;
 404         struct fpga_manager *mgr;
 405         u16 cmd, val;
 406         u32 regval;
 407         int ret;
 408
 409         /*
 410          * First check if this is the expected FPGA device. PCI config
 411          * space access works without enabling the PCI device, memory
 412          * space access is enabled further down.
 413          */
 414         pci_read_config_word(pdev, VSE_PCIE_EXT_CAP_ID, &val);
 415         if (val != VSE_PCIE_EXT_CAP_ID_VAL) {
 416                 dev_err(&pdev->dev, "Wrong EXT_CAP_ID value 0x%x\n", val);
 417                 return -ENODEV;
 418         }
 419
 420         pci_read_config_dword(pdev, VSE_CVP_STATUS, &regval);
 421         if (!(regval & VSE_CVP_STATUS_CVP_EN)) {
 422                 dev_err(&pdev->dev,
 423                         "CVP is disabled for this device: CVP_STATUS Reg 0x%x\n",
 424                         regval);
 425                 return -ENODEV;
 426         }
 427
 428         conf = devm_kzalloc(&pdev->dev, sizeof(*conf), GFP_KERNEL);
 429         if (!conf)
 430                 return -ENOMEM;
 431
 432         /*
 433          * Enable memory BAR access. We cannot use pci_enable_device() here
 434          * because it will make the driver unusable with FPGA devices that
 435          * have additional big IOMEM resources (e.g. 4GiB BARs) on 32-bit
 436          * platform. Such BARs will not have an assigned address range and
 437          * pci_enable_device() will fail, complaining about not claimed BAR,
 438          * even if the concerned BAR is not needed for FPGA configuration
 439          * at all. Thus, enable the device via PCI config space command.
 440          */
 441         pci_read_config_word(pdev, PCI_COMMAND, &cmd);
 442         if (!(cmd & PCI_COMMAND_MEMORY)) {
 443                 cmd |= PCI_COMMAND_MEMORY;
 444                 pci_write_config_word(pdev, PCI_COMMAND, cmd);
 445         }
 446
 447         ret = pci_request_region(pdev, CVP_BAR, "CVP");
 448         if (ret) {
 449                 dev_err(&pdev->dev, "Requesting CVP BAR region failed\n");
 450                 goto err_disable;
 451         }
 452
 453         conf->pci_dev = pdev;
 454         conf->write_data = altera_cvp_write_data_iomem;
 455
 456         conf->map = pci_iomap(pdev, CVP_BAR, 0);
 457         if (!conf->map) {
 458                 dev_warn(&pdev->dev, "Mapping CVP BAR failed\n");
 459                 conf->write_data = altera_cvp_write_data_config;
 460         }
 461
 462         snprintf(conf->mgr_name, sizeof(conf->mgr_name), "%s @%s",
 463                  ALTERA_CVP_MGR_NAME, pci_name(pdev));
 464
 465         mgr = devm_fpga_mgr_create(&pdev->dev, conf->mgr_name,
 466                                    &altera_cvp_ops, conf);
 467         if (!mgr) {
 468                 ret = -ENOMEM;
 469                 goto err_unmap;
 470         }
 471
 472         pci_set_drvdata(pdev, mgr);
 473
 474         ret = fpga_mgr_register(mgr);
 475         if (ret)
 476                 goto err_unmap;
 477
 478         return 0;
 479
 480 err_unmap:
 481         if (conf->map)
 482                 pci_iounmap(pdev, conf->map);
 483         pci_release_region(pdev, CVP_BAR);
 484 err_disable:
 485         cmd &= ~PCI_COMMAND_MEMORY;
 486         pci_write_config_word(pdev, PCI_COMMAND, cmd);
 487         return ret;
 488 }
 489
 490 static void altera_cvp_remove(struct pci_dev *pdev)
 491 {
 492         struct fpga_manager *mgr = pci_get_drvdata(pdev);
 493         struct altera_cvp_conf *conf = mgr->priv;
 494         u16 cmd;
 495
 496         fpga_mgr_unregister(mgr);
 497         if (conf->map)
 498                 pci_iounmap(pdev, conf->map);
 499         pci_release_region(pdev, CVP_BAR);
 500         pci_read_config_word(pdev, PCI_COMMAND, &cmd);
 501         cmd &= ~PCI_COMMAND_MEMORY;
 502         pci_write_config_word(pdev, PCI_COMMAND, cmd);
 503 }
 504
 505 static int __init altera_cvp_init(void)
 506 {
 507         int ret;
 508
 509         ret = pci_register_driver(&altera_cvp_driver);
 510         if (ret)
 511                 return ret;
 512
 513         ret = driver_create_file(&altera_cvp_driver.driver,
 514                                  &driver_attr_chkcfg);
 515         if (ret)
 516                 pr_warn("Can't create sysfs chkcfg file\n");
 517
 518         return 0;
 519 }
 520
 521 static void __exit altera_cvp_exit(void)
 522 {
 523         driver_remove_file(&altera_cvp_driver.driver, &driver_attr_chkcfg);
 524         pci_unregister_driver(&altera_cvp_driver);
 525 }
 526
 527 module_init(altera_cvp_init);
 528 module_exit(altera_cvp_exit);
 529
 530 MODULE_LICENSE("GPL v2");
 531 MODULE_AUTHOR("Anatolij Gustschin <agust@denx.de>");
 532 MODULE_DESCRIPTION("Module to load Altera FPGA over CvP");