arch/sparc/kernel/pci_msi.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* pci_msi.c: Sparc64 MSI support common layer.
   3  *
   4  * Copyright (C) 2007 David S. Miller (davem@davemloft.net)
   5  */
   6 #include <linux/kernel.h>
   7 #include <linux/interrupt.h>
   8 #include <linux/slab.h>
   9 #include <linux/irq.h>
  10
  11 #include "pci_impl.h"
  12
  13 static irqreturn_t sparc64_msiq_interrupt(int irq, void *cookie)
  14 {
  15         struct sparc64_msiq_cookie *msiq_cookie = cookie;
  16         struct pci_pbm_info *pbm = msiq_cookie->pbm;
  17         unsigned long msiqid = msiq_cookie->msiqid;
  18         const struct sparc64_msiq_ops *ops;
  19         unsigned long orig_head, head;
  20         int err;
  21
  22         ops = pbm->msi_ops;
  23
  24         err = ops->get_head(pbm, msiqid, &head);
  25         if (unlikely(err < 0))
  26                 goto err_get_head;
  27
  28         orig_head = head;
  29         for (;;) {
  30                 unsigned long msi;
  31
  32                 err = ops->dequeue_msi(pbm, msiqid, &head, &msi);
  33                 if (likely(err > 0)) {
  34                         unsigned int irq;
  35
  36                         irq = pbm->msi_irq_table[msi - pbm->msi_first];
  37                         generic_handle_irq(irq);
  38                 }
  39
  40                 if (unlikely(err < 0))
  41                         goto err_dequeue;
  42
  43                 if (err == 0)
  44                         break;
  45         }
  46         if (likely(head != orig_head)) {
  47                 err = ops->set_head(pbm, msiqid, head);
  48                 if (unlikely(err < 0))
  49                         goto err_set_head;
  50         }
  51         return IRQ_HANDLED;
  52
  53 err_get_head:
  54         printk(KERN_EMERG "MSI: Get head on msiqid[%lu] gives error %d\n",
  55                msiqid, err);
  56         goto err_out;
  57
  58 err_dequeue:
  59         printk(KERN_EMERG "MSI: Dequeue head[%lu] from msiqid[%lu] "
  60                "gives error %d\n",
  61                head, msiqid, err);
  62         goto err_out;
  63
  64 err_set_head:
  65         printk(KERN_EMERG "MSI: Set head[%lu] on msiqid[%lu] "
  66                "gives error %d\n",
  67                head, msiqid, err);
  68         goto err_out;
  69
  70 err_out:
  71         return IRQ_NONE;
  72 }
  73
  74 static u32 pick_msiq(struct pci_pbm_info *pbm)
  75 {
  76         static DEFINE_SPINLOCK(rotor_lock);
  77         unsigned long flags;
  78         u32 ret, rotor;
  79
  80         spin_lock_irqsave(&rotor_lock, flags);
  81
  82         rotor = pbm->msiq_rotor;
  83         ret = pbm->msiq_first + rotor;
  84
  85         if (++rotor >= pbm->msiq_num)
  86                 rotor = 0;
  87         pbm->msiq_rotor = rotor;
  88
  89         spin_unlock_irqrestore(&rotor_lock, flags);
  90
  91         return ret;
  92 }
  93
  94
  95 static int alloc_msi(struct pci_pbm_info *pbm)
  96 {
  97         int i;
  98
  99         for (i = 0; i < pbm->msi_num; i++) {
 100                 if (!test_and_set_bit(i, pbm->msi_bitmap))
 101                         return i + pbm->msi_first;
 102         }
 103
 104         return -ENOENT;
 105 }
 106
 107 static void free_msi(struct pci_pbm_info *pbm, int msi_num)
 108 {
 109         msi_num -= pbm->msi_first;
 110         clear_bit(msi_num, pbm->msi_bitmap);
 111 }
 112
 113 static struct irq_chip msi_irq = {
 114         .name           = "PCI-MSI",
 115         .irq_mask       = pci_msi_mask_irq,
 116         .irq_unmask     = pci_msi_unmask_irq,
 117         .irq_enable     = pci_msi_unmask_irq,
 118         .irq_disable    = pci_msi_mask_irq,
 119         /* XXX affinity XXX */
 120 };
 121
 122 static int sparc64_setup_msi_irq(unsigned int *irq_p,
 123                                  struct pci_dev *pdev,
 124                                  struct msi_desc *entry)
 125 {
 126         struct pci_pbm_info *pbm = pdev->dev.archdata.host_controller;
 127         const struct sparc64_msiq_ops *ops = pbm->msi_ops;
 128         struct msi_msg msg;
 129         int msi, err;
 130         u32 msiqid;
 131
 132         *irq_p = irq_alloc(0, 0);
 133         err = -ENOMEM;
 134         if (!*irq_p)
 135                 goto out_err;
 136
 137         irq_set_chip_and_handler_name(*irq_p, &msi_irq, handle_simple_irq,
 138                                       "MSI");
 139
 140         err = alloc_msi(pbm);
 141         if (unlikely(err < 0))
 142                 goto out_irq_free;
 143
 144         msi = err;
 145
 146         msiqid = pick_msiq(pbm);
 147
 148         err = ops->msi_setup(pbm, msiqid, msi,
 149                              (entry->msi_attrib.is_64 ? 1 : 0));
 150         if (err)
 151                 goto out_msi_free;
 152
 153         pbm->msi_irq_table[msi - pbm->msi_first] = *irq_p;
 154
 155         if (entry->msi_attrib.is_64) {
 156                 msg.address_hi = pbm->msi64_start >> 32;
 157                 msg.address_lo = pbm->msi64_start & 0xffffffff;
 158         } else {
 159                 msg.address_hi = 0;
 160                 msg.address_lo = pbm->msi32_start;
 161         }
 162         msg.data = msi;
 163
 164         irq_set_msi_desc(*irq_p, entry);
 165         pci_write_msi_msg(*irq_p, &msg);
 166
 167         return 0;
 168
 169 out_msi_free:
 170         free_msi(pbm, msi);
 171
 172 out_irq_free:
 173         irq_set_chip(*irq_p, NULL);
 174         irq_free(*irq_p);
 175         *irq_p = 0;
 176
 177 out_err:
 178         return err;
 179 }
 180
 181 static void sparc64_teardown_msi_irq(unsigned int irq,
 182                                      struct pci_dev *pdev)
 183 {
 184         struct pci_pbm_info *pbm = pdev->dev.archdata.host_controller;
 185         const struct sparc64_msiq_ops *ops = pbm->msi_ops;
 186         unsigned int msi_num;
 187         int i, err;
 188
 189         for (i = 0; i < pbm->msi_num; i++) {
 190                 if (pbm->msi_irq_table[i] == irq)
 191                         break;
 192         }
 193         if (i >= pbm->msi_num) {
 194                 printk(KERN_ERR "%s: teardown: No MSI for irq %u\n",
 195                        pbm->name, irq);
 196                 return;
 197         }
 198
 199         msi_num = pbm->msi_first + i;
 200         pbm->msi_irq_table[i] = ~0U;
 201
 202         err = ops->msi_teardown(pbm, msi_num);
 203         if (err) {
 204                 printk(KERN_ERR "%s: teardown: ops->teardown() on MSI %u, "
 205                        "irq %u, gives error %d\n",
 206                        pbm->name, msi_num, irq, err);
 207                 return;
 208         }
 209
 210         free_msi(pbm, msi_num);
 211
 212         irq_set_chip(irq, NULL);
 213         irq_free(irq);
 214 }
 215
 216 static int msi_bitmap_alloc(struct pci_pbm_info *pbm)
 217 {
 218         unsigned long size, bits_per_ulong;
 219
 220         bits_per_ulong = sizeof(unsigned long) * 8;
 221         size = (pbm->msi_num + (bits_per_ulong - 1)) & ~(bits_per_ulong - 1);
 222         size /= 8;
 223         BUG_ON(size % sizeof(unsigned long));
 224
 225         pbm->msi_bitmap = kzalloc(size, GFP_KERNEL);
 226         if (!pbm->msi_bitmap)
 227                 return -ENOMEM;
 228
 229         return 0;
 230 }
 231
 232 static void msi_bitmap_free(struct pci_pbm_info *pbm)
 233 {
 234         kfree(pbm->msi_bitmap);
 235         pbm->msi_bitmap = NULL;
 236 }
 237
 238 static int msi_table_alloc(struct pci_pbm_info *pbm)
 239 {
 240         int size, i;
 241
 242         size = pbm->msiq_num * sizeof(struct sparc64_msiq_cookie);
 243         pbm->msiq_irq_cookies = kzalloc(size, GFP_KERNEL);
 244         if (!pbm->msiq_irq_cookies)
 245                 return -ENOMEM;
 246
 247         for (i = 0; i < pbm->msiq_num; i++) {
 248                 struct sparc64_msiq_cookie *p;
 249
 250                 p = &pbm->msiq_irq_cookies[i];
 251                 p->pbm = pbm;
 252                 p->msiqid = pbm->msiq_first + i;
 253         }
 254
 255         size = pbm->msi_num * sizeof(unsigned int);
 256         pbm->msi_irq_table = kzalloc(size, GFP_KERNEL);
 257         if (!pbm->msi_irq_table) {
 258                 kfree(pbm->msiq_irq_cookies);
 259                 pbm->msiq_irq_cookies = NULL;
 260                 return -ENOMEM;
 261         }
 262
 263         return 0;
 264 }
 265
 266 static void msi_table_free(struct pci_pbm_info *pbm)
 267 {
 268         kfree(pbm->msiq_irq_cookies);
 269         pbm->msiq_irq_cookies = NULL;
 270
 271         kfree(pbm->msi_irq_table);
 272         pbm->msi_irq_table = NULL;
 273 }
 274
 275 static int bringup_one_msi_queue(struct pci_pbm_info *pbm,
 276                                  const struct sparc64_msiq_ops *ops,
 277                                  unsigned long msiqid,
 278                                  unsigned long devino)
 279 {
 280         int irq = ops->msiq_build_irq(pbm, msiqid, devino);
 281         int err, nid;
 282
 283         if (irq < 0)
 284                 return irq;
 285
 286         nid = pbm->numa_node;
 287         if (nid != -1) {
 288                 cpumask_t numa_mask;
 289
 290                 cpumask_copy(&numa_mask, cpumask_of_node(nid));
 291                 irq_set_affinity(irq, &numa_mask);
 292         }
 293         err = request_irq(irq, sparc64_msiq_interrupt, 0,
 294                           "MSIQ",
 295                           &pbm->msiq_irq_cookies[msiqid - pbm->msiq_first]);
 296         if (err)
 297                 return err;
 298
 299         return 0;
 300 }
 301
 302 static int sparc64_bringup_msi_queues(struct pci_pbm_info *pbm,
 303                                       const struct sparc64_msiq_ops *ops)
 304 {
 305         int i;
 306
 307         for (i = 0; i < pbm->msiq_num; i++) {
 308                 unsigned long msiqid = i + pbm->msiq_first;
 309                 unsigned long devino = i + pbm->msiq_first_devino;
 310                 int err;
 311
 312                 err = bringup_one_msi_queue(pbm, ops, msiqid, devino);
 313                 if (err)
 314                         return err;
 315         }
 316
 317         return 0;
 318 }
 319
 320 void sparc64_pbm_msi_init(struct pci_pbm_info *pbm,
 321                           const struct sparc64_msiq_ops *ops)
 322 {
 323         const u32 *val;
 324         int len;
 325
 326         val = of_get_property(pbm->op->dev.of_node, "#msi-eqs", &len);
 327         if (!val || len != 4)
 328                 goto no_msi;
 329         pbm->msiq_num = *val;
 330         if (pbm->msiq_num) {
 331                 const struct msiq_prop {
 332                         u32 first_msiq;
 333                         u32 num_msiq;
 334                         u32 first_devino;
 335                 } *mqp;
 336                 const struct msi_range_prop {
 337                         u32 first_msi;
 338                         u32 num_msi;
 339                 } *mrng;
 340                 const struct addr_range_prop {
 341                         u32 msi32_high;
 342                         u32 msi32_low;
 343                         u32 msi32_len;
 344                         u32 msi64_high;
 345                         u32 msi64_low;
 346                         u32 msi64_len;
 347                 } *arng;
 348
 349                 val = of_get_property(pbm->op->dev.of_node, "msi-eq-size", &len);
 350                 if (!val || len != 4)
 351                         goto no_msi;
 352
 353                 pbm->msiq_ent_count = *val;
 354
 355                 mqp = of_get_property(pbm->op->dev.of_node,
 356                                       "msi-eq-to-devino", &len);
 357                 if (!mqp)
 358                         mqp = of_get_property(pbm->op->dev.of_node,
 359                                               "msi-eq-devino", &len);
 360                 if (!mqp || len != sizeof(struct msiq_prop))
 361                         goto no_msi;
 362
 363                 pbm->msiq_first = mqp->first_msiq;
 364                 pbm->msiq_first_devino = mqp->first_devino;
 365
 366                 val = of_get_property(pbm->op->dev.of_node, "#msi", &len);
 367                 if (!val || len != 4)
 368                         goto no_msi;
 369                 pbm->msi_num = *val;
 370
 371                 mrng = of_get_property(pbm->op->dev.of_node, "msi-ranges", &len);
 372                 if (!mrng || len != sizeof(struct msi_range_prop))
 373                         goto no_msi;
 374                 pbm->msi_first = mrng->first_msi;
 375
 376                 val = of_get_property(pbm->op->dev.of_node, "msi-data-mask", &len);
 377                 if (!val || len != 4)
 378                         goto no_msi;
 379                 pbm->msi_data_mask = *val;
 380
 381                 val = of_get_property(pbm->op->dev.of_node, "msix-data-width", &len);
 382                 if (!val || len != 4)
 383                         goto no_msi;
 384                 pbm->msix_data_width = *val;
 385
 386                 arng = of_get_property(pbm->op->dev.of_node, "msi-address-ranges",
 387                                        &len);
 388                 if (!arng || len != sizeof(struct addr_range_prop))
 389                         goto no_msi;
 390                 pbm->msi32_start = ((u64)arng->msi32_high << 32) |
 391                         (u64) arng->msi32_low;
 392                 pbm->msi64_start = ((u64)arng->msi64_high << 32) |
 393                         (u64) arng->msi64_low;
 394                 pbm->msi32_len = arng->msi32_len;
 395                 pbm->msi64_len = arng->msi64_len;
 396
 397                 if (msi_bitmap_alloc(pbm))
 398                         goto no_msi;
 399
 400                 if (msi_table_alloc(pbm)) {
 401                         msi_bitmap_free(pbm);
 402                         goto no_msi;
 403                 }
 404
 405                 if (ops->msiq_alloc(pbm)) {
 406                         msi_table_free(pbm);
 407                         msi_bitmap_free(pbm);
 408                         goto no_msi;
 409                 }
 410
 411                 if (sparc64_bringup_msi_queues(pbm, ops)) {
 412                         ops->msiq_free(pbm);
 413                         msi_table_free(pbm);
 414                         msi_bitmap_free(pbm);
 415                         goto no_msi;
 416                 }
 417
 418                 printk(KERN_INFO "%s: MSI Queue first[%u] num[%u] count[%u] "
 419                        "devino[0x%x]\n",
 420                        pbm->name,
 421                        pbm->msiq_first, pbm->msiq_num,
 422                        pbm->msiq_ent_count,
 423                        pbm->msiq_first_devino);
 424                 printk(KERN_INFO "%s: MSI first[%u] num[%u] mask[0x%x] "
 425                        "width[%u]\n",
 426                        pbm->name,
 427                        pbm->msi_first, pbm->msi_num, pbm->msi_data_mask,
 428                        pbm->msix_data_width);
 429                 printk(KERN_INFO "%s: MSI addr32[0x%llx:0x%x] "
 430                        "addr64[0x%llx:0x%x]\n",
 431                        pbm->name,
 432                        pbm->msi32_start, pbm->msi32_len,
 433                        pbm->msi64_start, pbm->msi64_len);
 434                 printk(KERN_INFO "%s: MSI queues at RA [%016lx]\n",
 435                        pbm->name,
 436                        __pa(pbm->msi_queues));
 437
 438                 pbm->msi_ops = ops;
 439                 pbm->setup_msi_irq = sparc64_setup_msi_irq;
 440                 pbm->teardown_msi_irq = sparc64_teardown_msi_irq;
 441         }
 442         return;
 443
 444 no_msi:
 445         pbm->msiq_num = 0;
 446         printk(KERN_INFO "%s: No MSI support.\n", pbm->name);
 447 }