drivers/ntb/hw/intel/ntb_hw_gen3.c

   1 /*
   2  * This file is provided under a dual BSD/GPLv2 license.  When using or
   3  *   redistributing this file, you may do so under either license.
   4  *
   5  *   GPL LICENSE SUMMARY
   6  *
   7  *   Copyright(c) 2017 Intel Corporation. All rights reserved.
   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  *   BSD LICENSE
  14  *
  15  *   Copyright(c) 2017 Intel Corporation. All rights reserved.
  16  *
  17  *   Redistribution and use in source and binary forms, with or without
  18  *   modification, are permitted provided that the following conditions
  19  *   are met:
  20  *
  21  *     * Redistributions of source code must retain the above copyright
  22  *       notice, this list of conditions and the following disclaimer.
  23  *     * Redistributions in binary form must reproduce the above copy
  24  *       notice, this list of conditions and the following disclaimer in
  25  *       the documentation and/or other materials provided with the
  26  *       distribution.
  27  *     * Neither the name of Intel Corporation nor the names of its
  28  *       contributors may be used to endorse or promote products derived
  29  *       from this software without specific prior written permission.
  30  *
  31  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  34  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  36  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  37  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  38  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  39  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  40  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  41  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  42  *
  43  * Intel PCIe GEN3 NTB Linux driver
  44  *
  45  */
  46
  47 #include <linux/debugfs.h>
  48 #include <linux/delay.h>
  49 #include <linux/init.h>
  50 #include <linux/interrupt.h>
  51 #include <linux/module.h>
  52 #include <linux/pci.h>
  53 #include <linux/random.h>
  54 #include <linux/slab.h>
  55 #include <linux/ntb.h>
  56
  57 #include "ntb_hw_intel.h"
  58 #include "ntb_hw_gen1.h"
  59 #include "ntb_hw_gen3.h"
  60
  61 static int gen3_poll_link(struct intel_ntb_dev *ndev);
  62
  63 static const struct intel_ntb_reg gen3_reg = {
  64         .poll_link              = gen3_poll_link,
  65         .link_is_up             = xeon_link_is_up,
  66         .db_ioread              = gen3_db_ioread,
  67         .db_iowrite             = gen3_db_iowrite,
  68         .db_size                = sizeof(u32),
  69         .ntb_ctl                = GEN3_NTBCNTL_OFFSET,
  70         .mw_bar                 = {2, 4},
  71 };
  72
  73 static const struct intel_ntb_alt_reg gen3_pri_reg = {
  74         .db_bell                = GEN3_EM_DOORBELL_OFFSET,
  75         .db_clear               = GEN3_IM_INT_STATUS_OFFSET,
  76         .db_mask                = GEN3_IM_INT_DISABLE_OFFSET,
  77         .spad                   = GEN3_IM_SPAD_OFFSET,
  78 };
  79
  80 static const struct intel_ntb_alt_reg gen3_b2b_reg = {
  81         .db_bell                = GEN3_IM_DOORBELL_OFFSET,
  82         .db_clear               = GEN3_EM_INT_STATUS_OFFSET,
  83         .db_mask                = GEN3_EM_INT_DISABLE_OFFSET,
  84         .spad                   = GEN3_B2B_SPAD_OFFSET,
  85 };
  86
  87 static const struct intel_ntb_xlat_reg gen3_sec_xlat = {
  88 /*      .bar0_base              = GEN3_EMBAR0_OFFSET, */
  89         .bar2_limit             = GEN3_IMBAR1XLMT_OFFSET,
  90         .bar2_xlat              = GEN3_IMBAR1XBASE_OFFSET,
  91 };
  92
  93 static int gen3_poll_link(struct intel_ntb_dev *ndev)
  94 {
  95         u16 reg_val;
  96         int rc;
  97
  98         ndev->reg->db_iowrite(ndev->db_link_mask,
  99                               ndev->self_mmio +
 100                               ndev->self_reg->db_clear);
 101
 102         rc = pci_read_config_word(ndev->ntb.pdev,
 103                                   GEN3_LINK_STATUS_OFFSET, &reg_val);
 104         if (rc)
 105                 return 0;
 106
 107         if (reg_val == ndev->lnk_sta)
 108                 return 0;
 109
 110         ndev->lnk_sta = reg_val;
 111
 112         return 1;
 113 }
 114
 115 static int gen3_init_isr(struct intel_ntb_dev *ndev)
 116 {
 117         int i;
 118
 119         /*
 120          * The MSIX vectors and the interrupt status bits are not lined up
 121          * on Skylake. By default the link status bit is bit 32, however it
 122          * is by default MSIX vector0. We need to fixup to line them up.
 123          * The vectors at reset is 1-32,0. We need to reprogram to 0-32.
 124          */
 125
 126         for (i = 0; i < GEN3_DB_MSIX_VECTOR_COUNT; i++)
 127                 iowrite8(i, ndev->self_mmio + GEN3_INTVEC_OFFSET + i);
 128
 129         /* move link status down one as workaround */
 130         if (ndev->hwerr_flags & NTB_HWERR_MSIX_VECTOR32_BAD) {
 131                 iowrite8(GEN3_DB_MSIX_VECTOR_COUNT - 2,
 132                          ndev->self_mmio + GEN3_INTVEC_OFFSET +
 133                          (GEN3_DB_MSIX_VECTOR_COUNT - 1));
 134         }
 135
 136         return ndev_init_isr(ndev, GEN3_DB_MSIX_VECTOR_COUNT,
 137                              GEN3_DB_MSIX_VECTOR_COUNT,
 138                              GEN3_DB_MSIX_VECTOR_SHIFT,
 139                              GEN3_DB_TOTAL_SHIFT);
 140 }
 141
 142 static int gen3_setup_b2b_mw(struct intel_ntb_dev *ndev,
 143                             const struct intel_b2b_addr *addr,
 144                             const struct intel_b2b_addr *peer_addr)
 145 {
 146         struct pci_dev *pdev;
 147         void __iomem *mmio;
 148         phys_addr_t bar_addr;
 149
 150         pdev = ndev->ntb.pdev;
 151         mmio = ndev->self_mmio;
 152
 153         /* setup incoming bar limits == base addrs (zero length windows) */
 154         bar_addr = addr->bar2_addr64;
 155         iowrite64(bar_addr, mmio + GEN3_IMBAR1XLMT_OFFSET);
 156         bar_addr = ioread64(mmio + GEN3_IMBAR1XLMT_OFFSET);
 157         dev_dbg(&pdev->dev, "IMBAR1XLMT %#018llx\n", bar_addr);
 158
 159         bar_addr = addr->bar4_addr64;
 160         iowrite64(bar_addr, mmio + GEN3_IMBAR2XLMT_OFFSET);
 161         bar_addr = ioread64(mmio + GEN3_IMBAR2XLMT_OFFSET);
 162         dev_dbg(&pdev->dev, "IMBAR2XLMT %#018llx\n", bar_addr);
 163
 164         /* zero incoming translation addrs */
 165         iowrite64(0, mmio + GEN3_IMBAR1XBASE_OFFSET);
 166         iowrite64(0, mmio + GEN3_IMBAR2XBASE_OFFSET);
 167
 168         ndev->peer_mmio = ndev->self_mmio;
 169
 170         return 0;
 171 }
 172
 173 static int gen3_init_ntb(struct intel_ntb_dev *ndev)
 174 {
 175         int rc;
 176
 177
 178         ndev->mw_count = XEON_MW_COUNT;
 179         ndev->spad_count = GEN3_SPAD_COUNT;
 180         ndev->db_count = GEN3_DB_COUNT;
 181         ndev->db_link_mask = GEN3_DB_LINK_BIT;
 182
 183         /* DB fixup for using 31 right now */
 184         if (ndev->hwerr_flags & NTB_HWERR_MSIX_VECTOR32_BAD)
 185                 ndev->db_link_mask |= BIT_ULL(31);
 186
 187         switch (ndev->ntb.topo) {
 188         case NTB_TOPO_B2B_USD:
 189         case NTB_TOPO_B2B_DSD:
 190                 ndev->self_reg = &gen3_pri_reg;
 191                 ndev->peer_reg = &gen3_b2b_reg;
 192                 ndev->xlat_reg = &gen3_sec_xlat;
 193
 194                 if (ndev->ntb.topo == NTB_TOPO_B2B_USD) {
 195                         rc = gen3_setup_b2b_mw(ndev,
 196                                               &xeon_b2b_dsd_addr,
 197                                               &xeon_b2b_usd_addr);
 198                 } else {
 199                         rc = gen3_setup_b2b_mw(ndev,
 200                                               &xeon_b2b_usd_addr,
 201                                               &xeon_b2b_dsd_addr);
 202                 }
 203
 204                 if (rc)
 205                         return rc;
 206
 207                 /* Enable Bus Master and Memory Space on the secondary side */
 208                 iowrite16(PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER,
 209                           ndev->self_mmio + GEN3_SPCICMD_OFFSET);
 210
 211                 break;
 212
 213         default:
 214                 return -EINVAL;
 215         }
 216
 217         ndev->db_valid_mask = BIT_ULL(ndev->db_count) - 1;
 218
 219         ndev->reg->db_iowrite(ndev->db_valid_mask,
 220                               ndev->self_mmio +
 221                               ndev->self_reg->db_mask);
 222
 223         return 0;
 224 }
 225
 226 int gen3_init_dev(struct intel_ntb_dev *ndev)
 227 {
 228         struct pci_dev *pdev;
 229         u8 ppd;
 230         int rc;
 231
 232         pdev = ndev->ntb.pdev;
 233
 234         ndev->reg = &gen3_reg;
 235
 236         rc = pci_read_config_byte(pdev, XEON_PPD_OFFSET, &ppd);
 237         if (rc)
 238                 return -EIO;
 239
 240         ndev->ntb.topo = xeon_ppd_topo(ndev, ppd);
 241         dev_dbg(&pdev->dev, "ppd %#x topo %s\n", ppd,
 242                 ntb_topo_string(ndev->ntb.topo));
 243         if (ndev->ntb.topo == NTB_TOPO_NONE)
 244                 return -EINVAL;
 245
 246         ndev->hwerr_flags |= NTB_HWERR_MSIX_VECTOR32_BAD;
 247
 248         rc = gen3_init_ntb(ndev);
 249         if (rc)
 250                 return rc;
 251
 252         return gen3_init_isr(ndev);
 253 }
 254
 255 ssize_t ndev_ntb3_debugfs_read(struct file *filp, char __user *ubuf,
 256                                       size_t count, loff_t *offp)
 257 {
 258         struct intel_ntb_dev *ndev;
 259         void __iomem *mmio;
 260         char *buf;
 261         size_t buf_size;
 262         ssize_t ret, off;
 263         union { u64 v64; u32 v32; u16 v16; } u;
 264
 265         ndev = filp->private_data;
 266         mmio = ndev->self_mmio;
 267
 268         buf_size = min(count, 0x800ul);
 269
 270         buf = kmalloc(buf_size, GFP_KERNEL);
 271         if (!buf)
 272                 return -ENOMEM;
 273
 274         off = 0;
 275
 276         off += scnprintf(buf + off, buf_size - off,
 277                          "NTB Device Information:\n");
 278
 279         off += scnprintf(buf + off, buf_size - off,
 280                          "Connection Topology -\t%s\n",
 281                          ntb_topo_string(ndev->ntb.topo));
 282
 283         off += scnprintf(buf + off, buf_size - off,
 284                          "NTB CTL -\t\t%#06x\n", ndev->ntb_ctl);
 285         off += scnprintf(buf + off, buf_size - off,
 286                          "LNK STA -\t\t%#06x\n", ndev->lnk_sta);
 287
 288         if (!ndev->reg->link_is_up(ndev))
 289                 off += scnprintf(buf + off, buf_size - off,
 290                                  "Link Status -\t\tDown\n");
 291         else {
 292                 off += scnprintf(buf + off, buf_size - off,
 293                                  "Link Status -\t\tUp\n");
 294                 off += scnprintf(buf + off, buf_size - off,
 295                                  "Link Speed -\t\tPCI-E Gen %u\n",
 296                                  NTB_LNK_STA_SPEED(ndev->lnk_sta));
 297                 off += scnprintf(buf + off, buf_size - off,
 298                                  "Link Width -\t\tx%u\n",
 299                                  NTB_LNK_STA_WIDTH(ndev->lnk_sta));
 300         }
 301
 302         off += scnprintf(buf + off, buf_size - off,
 303                          "Memory Window Count -\t%u\n", ndev->mw_count);
 304         off += scnprintf(buf + off, buf_size - off,
 305                          "Scratchpad Count -\t%u\n", ndev->spad_count);
 306         off += scnprintf(buf + off, buf_size - off,
 307                          "Doorbell Count -\t%u\n", ndev->db_count);
 308         off += scnprintf(buf + off, buf_size - off,
 309                          "Doorbell Vector Count -\t%u\n", ndev->db_vec_count);
 310         off += scnprintf(buf + off, buf_size - off,
 311                          "Doorbell Vector Shift -\t%u\n", ndev->db_vec_shift);
 312
 313         off += scnprintf(buf + off, buf_size - off,
 314                          "Doorbell Valid Mask -\t%#llx\n", ndev->db_valid_mask);
 315         off += scnprintf(buf + off, buf_size - off,
 316                          "Doorbell Link Mask -\t%#llx\n", ndev->db_link_mask);
 317         off += scnprintf(buf + off, buf_size - off,
 318                          "Doorbell Mask Cached -\t%#llx\n", ndev->db_mask);
 319
 320         u.v64 = ndev_db_read(ndev, mmio + ndev->self_reg->db_mask);
 321         off += scnprintf(buf + off, buf_size - off,
 322                          "Doorbell Mask -\t\t%#llx\n", u.v64);
 323
 324         u.v64 = ndev_db_read(ndev, mmio + ndev->self_reg->db_bell);
 325         off += scnprintf(buf + off, buf_size - off,
 326                          "Doorbell Bell -\t\t%#llx\n", u.v64);
 327
 328         off += scnprintf(buf + off, buf_size - off,
 329                          "\nNTB Incoming XLAT:\n");
 330
 331         u.v64 = ioread64(mmio + GEN3_IMBAR1XBASE_OFFSET);
 332         off += scnprintf(buf + off, buf_size - off,
 333                          "IMBAR1XBASE -\t\t%#018llx\n", u.v64);
 334
 335         u.v64 = ioread64(mmio + GEN3_IMBAR2XBASE_OFFSET);
 336         off += scnprintf(buf + off, buf_size - off,
 337                          "IMBAR2XBASE -\t\t%#018llx\n", u.v64);
 338
 339         u.v64 = ioread64(mmio + GEN3_IMBAR1XLMT_OFFSET);
 340         off += scnprintf(buf + off, buf_size - off,
 341                          "IMBAR1XLMT -\t\t\t%#018llx\n", u.v64);
 342
 343         u.v64 = ioread64(mmio + GEN3_IMBAR2XLMT_OFFSET);
 344         off += scnprintf(buf + off, buf_size - off,
 345                          "IMBAR2XLMT -\t\t\t%#018llx\n", u.v64);
 346
 347         if (ntb_topo_is_b2b(ndev->ntb.topo)) {
 348                 off += scnprintf(buf + off, buf_size - off,
 349                                  "\nNTB Outgoing B2B XLAT:\n");
 350
 351                 u.v64 = ioread64(mmio + GEN3_EMBAR1XBASE_OFFSET);
 352                 off += scnprintf(buf + off, buf_size - off,
 353                                  "EMBAR1XBASE -\t\t%#018llx\n", u.v64);
 354
 355                 u.v64 = ioread64(mmio + GEN3_EMBAR2XBASE_OFFSET);
 356                 off += scnprintf(buf + off, buf_size - off,
 357                                  "EMBAR2XBASE -\t\t%#018llx\n", u.v64);
 358
 359                 u.v64 = ioread64(mmio + GEN3_EMBAR1XLMT_OFFSET);
 360                 off += scnprintf(buf + off, buf_size - off,
 361                                  "EMBAR1XLMT -\t\t%#018llx\n", u.v64);
 362
 363                 u.v64 = ioread64(mmio + GEN3_EMBAR2XLMT_OFFSET);
 364                 off += scnprintf(buf + off, buf_size - off,
 365                                  "EMBAR2XLMT -\t\t%#018llx\n", u.v64);
 366
 367                 off += scnprintf(buf + off, buf_size - off,
 368                                  "\nNTB Secondary BAR:\n");
 369
 370                 u.v64 = ioread64(mmio + GEN3_EMBAR0_OFFSET);
 371                 off += scnprintf(buf + off, buf_size - off,
 372                                  "EMBAR0 -\t\t%#018llx\n", u.v64);
 373
 374                 u.v64 = ioread64(mmio + GEN3_EMBAR1_OFFSET);
 375                 off += scnprintf(buf + off, buf_size - off,
 376                                  "EMBAR1 -\t\t%#018llx\n", u.v64);
 377
 378                 u.v64 = ioread64(mmio + GEN3_EMBAR2_OFFSET);
 379                 off += scnprintf(buf + off, buf_size - off,
 380                                  "EMBAR2 -\t\t%#018llx\n", u.v64);
 381         }
 382
 383         off += scnprintf(buf + off, buf_size - off,
 384                          "\nNTB Statistics:\n");
 385
 386         u.v16 = ioread16(mmio + GEN3_USMEMMISS_OFFSET);
 387         off += scnprintf(buf + off, buf_size - off,
 388                          "Upstream Memory Miss -\t%u\n", u.v16);
 389
 390         off += scnprintf(buf + off, buf_size - off,
 391                          "\nNTB Hardware Errors:\n");
 392
 393         if (!pci_read_config_word(ndev->ntb.pdev,
 394                                   GEN3_DEVSTS_OFFSET, &u.v16))
 395                 off += scnprintf(buf + off, buf_size - off,
 396                                  "DEVSTS -\t\t%#06x\n", u.v16);
 397
 398         if (!pci_read_config_word(ndev->ntb.pdev,
 399                                   GEN3_LINK_STATUS_OFFSET, &u.v16))
 400                 off += scnprintf(buf + off, buf_size - off,
 401                                  "LNKSTS -\t\t%#06x\n", u.v16);
 402
 403         if (!pci_read_config_dword(ndev->ntb.pdev,
 404                                    GEN3_UNCERRSTS_OFFSET, &u.v32))
 405                 off += scnprintf(buf + off, buf_size - off,
 406                                  "UNCERRSTS -\t\t%#06x\n", u.v32);
 407
 408         if (!pci_read_config_dword(ndev->ntb.pdev,
 409                                    GEN3_CORERRSTS_OFFSET, &u.v32))
 410                 off += scnprintf(buf + off, buf_size - off,
 411                                  "CORERRSTS -\t\t%#06x\n", u.v32);
 412
 413         ret = simple_read_from_buffer(ubuf, count, offp, buf, off);
 414         kfree(buf);
 415         return ret;
 416 }
 417
 418 static int intel_ntb3_link_enable(struct ntb_dev *ntb,
 419                                   enum ntb_speed max_speed,
 420                                   enum ntb_width max_width)
 421 {
 422         struct intel_ntb_dev *ndev;
 423         u32 ntb_ctl;
 424
 425         ndev = container_of(ntb, struct intel_ntb_dev, ntb);
 426
 427         dev_dbg(&ntb->pdev->dev,
 428                 "Enabling link with max_speed %d max_width %d\n",
 429                 max_speed, max_width);
 430
 431         if (max_speed != NTB_SPEED_AUTO)
 432                 dev_dbg(&ntb->pdev->dev, "ignoring max_speed %d\n", max_speed);
 433         if (max_width != NTB_WIDTH_AUTO)
 434                 dev_dbg(&ntb->pdev->dev, "ignoring max_width %d\n", max_width);
 435
 436         ntb_ctl = ioread32(ndev->self_mmio + ndev->reg->ntb_ctl);
 437         ntb_ctl &= ~(NTB_CTL_DISABLE | NTB_CTL_CFG_LOCK);
 438         ntb_ctl |= NTB_CTL_P2S_BAR2_SNOOP | NTB_CTL_S2P_BAR2_SNOOP;
 439         ntb_ctl |= NTB_CTL_P2S_BAR4_SNOOP | NTB_CTL_S2P_BAR4_SNOOP;
 440         iowrite32(ntb_ctl, ndev->self_mmio + ndev->reg->ntb_ctl);
 441
 442         return 0;
 443 }
 444 static int intel_ntb3_mw_set_trans(struct ntb_dev *ntb, int pidx, int idx,
 445                                    dma_addr_t addr, resource_size_t size)
 446 {
 447         struct intel_ntb_dev *ndev = ntb_ndev(ntb);
 448         unsigned long xlat_reg, limit_reg;
 449         resource_size_t bar_size, mw_size;
 450         void __iomem *mmio;
 451         u64 base, limit, reg_val;
 452         int bar;
 453
 454         if (pidx != NTB_DEF_PEER_IDX)
 455                 return -EINVAL;
 456
 457         if (idx >= ndev->b2b_idx && !ndev->b2b_off)
 458                 idx += 1;
 459
 460         bar = ndev_mw_to_bar(ndev, idx);
 461         if (bar < 0)
 462                 return bar;
 463
 464         bar_size = pci_resource_len(ndev->ntb.pdev, bar);
 465
 466         if (idx == ndev->b2b_idx)
 467                 mw_size = bar_size - ndev->b2b_off;
 468         else
 469                 mw_size = bar_size;
 470
 471         /* hardware requires that addr is aligned to bar size */
 472         if (addr & (bar_size - 1))
 473                 return -EINVAL;
 474
 475         /* make sure the range fits in the usable mw size */
 476         if (size > mw_size)
 477                 return -EINVAL;
 478
 479         mmio = ndev->self_mmio;
 480         xlat_reg = ndev->xlat_reg->bar2_xlat + (idx * 0x10);
 481         limit_reg = ndev->xlat_reg->bar2_limit + (idx * 0x10);
 482         base = pci_resource_start(ndev->ntb.pdev, bar);
 483
 484         /* Set the limit if supported, if size is not mw_size */
 485         if (limit_reg && size != mw_size)
 486                 limit = base + size;
 487         else
 488                 limit = base + mw_size;
 489
 490         /* set and verify setting the translation address */
 491         iowrite64(addr, mmio + xlat_reg);
 492         reg_val = ioread64(mmio + xlat_reg);
 493         if (reg_val != addr) {
 494                 iowrite64(0, mmio + xlat_reg);
 495                 return -EIO;
 496         }
 497
 498         dev_dbg(&ntb->pdev->dev, "BAR %d IMBARXBASE: %#Lx\n", bar, reg_val);
 499
 500         /* set and verify setting the limit */
 501         iowrite64(limit, mmio + limit_reg);
 502         reg_val = ioread64(mmio + limit_reg);
 503         if (reg_val != limit) {
 504                 iowrite64(base, mmio + limit_reg);
 505                 iowrite64(0, mmio + xlat_reg);
 506                 return -EIO;
 507         }
 508
 509         dev_dbg(&ntb->pdev->dev, "BAR %d IMBARXLMT: %#Lx\n", bar, reg_val);
 510
 511         /* setup the EP */
 512         limit_reg = ndev->xlat_reg->bar2_limit + (idx * 0x10) + 0x4000;
 513         base = ioread64(mmio + GEN3_EMBAR1_OFFSET + (8 * idx));
 514         base &= ~0xf;
 515
 516         if (limit_reg && size != mw_size)
 517                 limit = base + size;
 518         else
 519                 limit = base + mw_size;
 520
 521         /* set and verify setting the limit */
 522         iowrite64(limit, mmio + limit_reg);
 523         reg_val = ioread64(mmio + limit_reg);
 524         if (reg_val != limit) {
 525                 iowrite64(base, mmio + limit_reg);
 526                 iowrite64(0, mmio + xlat_reg);
 527                 return -EIO;
 528         }
 529
 530         dev_dbg(&ntb->pdev->dev, "BAR %d EMBARXLMT: %#Lx\n", bar, reg_val);
 531
 532         return 0;
 533 }
 534
 535 static int intel_ntb3_peer_db_set(struct ntb_dev *ntb, u64 db_bits)
 536 {
 537         struct intel_ntb_dev *ndev = ntb_ndev(ntb);
 538         int bit;
 539
 540         if (db_bits & ~ndev->db_valid_mask)
 541                 return -EINVAL;
 542
 543         while (db_bits) {
 544                 bit = __ffs(db_bits);
 545                 iowrite32(1, ndev->peer_mmio +
 546                                 ndev->peer_reg->db_bell + (bit * 4));
 547                 db_bits &= db_bits - 1;
 548         }
 549
 550         return 0;
 551 }
 552
 553 static u64 intel_ntb3_db_read(struct ntb_dev *ntb)
 554 {
 555         struct intel_ntb_dev *ndev = ntb_ndev(ntb);
 556
 557         return ndev_db_read(ndev,
 558                             ndev->self_mmio +
 559                             ndev->self_reg->db_clear);
 560 }
 561
 562 static int intel_ntb3_db_clear(struct ntb_dev *ntb, u64 db_bits)
 563 {
 564         struct intel_ntb_dev *ndev = ntb_ndev(ntb);
 565
 566         return ndev_db_write(ndev, db_bits,
 567                              ndev->self_mmio +
 568                              ndev->self_reg->db_clear);
 569 }
 570
 571 const struct ntb_dev_ops intel_ntb3_ops = {
 572         .mw_count               = intel_ntb_mw_count,
 573         .mw_get_align           = intel_ntb_mw_get_align,
 574         .mw_set_trans           = intel_ntb3_mw_set_trans,
 575         .peer_mw_count          = intel_ntb_peer_mw_count,
 576         .peer_mw_get_addr       = intel_ntb_peer_mw_get_addr,
 577         .link_is_up             = intel_ntb_link_is_up,
 578         .link_enable            = intel_ntb3_link_enable,
 579         .link_disable           = intel_ntb_link_disable,
 580         .db_valid_mask          = intel_ntb_db_valid_mask,
 581         .db_vector_count        = intel_ntb_db_vector_count,
 582         .db_vector_mask         = intel_ntb_db_vector_mask,
 583         .db_read                = intel_ntb3_db_read,
 584         .db_clear               = intel_ntb3_db_clear,
 585         .db_set_mask            = intel_ntb_db_set_mask,
 586         .db_clear_mask          = intel_ntb_db_clear_mask,
 587         .peer_db_addr           = intel_ntb_peer_db_addr,
 588         .peer_db_set            = intel_ntb3_peer_db_set,
 589         .spad_is_unsafe         = intel_ntb_spad_is_unsafe,
 590         .spad_count             = intel_ntb_spad_count,
 591         .spad_read              = intel_ntb_spad_read,
 592         .spad_write             = intel_ntb_spad_write,
 593         .peer_spad_addr         = intel_ntb_peer_spad_addr,
 594         .peer_spad_read         = intel_ntb_peer_spad_read,
 595         .peer_spad_write        = intel_ntb_peer_spad_write,
 596 };
 597