drivers/irqchip/irq-gic-v3-its.c

   1 /*
   2  * Copyright (C) 2013, 2014 ARM Limited, All Rights Reserved.
   3  * Author: Marc Zyngier <marc.zyngier@arm.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <linux/bitmap.h>
  19 #include <linux/cpu.h>
  20 #include <linux/delay.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/log2.h>
  23 #include <linux/mm.h>
  24 #include <linux/msi.h>
  25 #include <linux/of.h>
  26 #include <linux/of_address.h>
  27 #include <linux/of_irq.h>
  28 #include <linux/of_pci.h>
  29 #include <linux/of_platform.h>
  30 #include <linux/percpu.h>
  31 #include <linux/slab.h>
  32
  33 #include <linux/irqchip/arm-gic-v3.h>
  34
  35 #include <asm/cacheflush.h>
  36 #include <asm/cputype.h>
  37 #include <asm/exception.h>
  38
  39 #include "irqchip.h"
  40
  41 #define ITS_FLAGS_CMDQ_NEEDS_FLUSHING           (1 << 0)
  42
  43 #define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING     (1 << 0)
  44
  45 /*
  46  * Collection structure - just an ID, and a redistributor address to
  47  * ping. We use one per CPU as a bag of interrupts assigned to this
  48  * CPU.
  49  */
  50 struct its_collection {
  51         u64                     target_address;
  52         u16                     col_id;
  53 };
  54
  55 /*
  56  * The ITS structure - contains most of the infrastructure, with the
  57  * msi_controller, the command queue, the collections, and the list of
  58  * devices writing to it.
  59  */
  60 struct its_node {
  61         raw_spinlock_t          lock;
  62         struct list_head        entry;
  63         struct msi_controller   msi_chip;
  64         struct irq_domain       *domain;
  65         void __iomem            *base;
  66         unsigned long           phys_base;
  67         struct its_cmd_block    *cmd_base;
  68         struct its_cmd_block    *cmd_write;
  69         void                    *tables[GITS_BASER_NR_REGS];
  70         struct its_collection   *collections;
  71         struct list_head        its_device_list;
  72         u64                     flags;
  73         u32                     ite_size;
  74 };
  75
  76 #define ITS_ITT_ALIGN           SZ_256
  77
  78 struct event_lpi_map {
  79         unsigned long           *lpi_map;
  80         u16                     *col_map;
  81         irq_hw_number_t         lpi_base;
  82         int                     nr_lpis;
  83 };
  84
  85 /*
  86  * The ITS view of a device - belongs to an ITS, a collection, owns an
  87  * interrupt translation table, and a list of interrupts.
  88  */
  89 struct its_device {
  90         struct list_head        entry;
  91         struct its_node         *its;
  92         struct event_lpi_map    event_map;
  93         void                    *itt;
  94         u32                     nr_ites;
  95         u32                     device_id;
  96 };
  97
  98 static LIST_HEAD(its_nodes);
  99 static DEFINE_SPINLOCK(its_lock);
 100 static struct device_node *gic_root_node;
 101 static struct rdists *gic_rdists;
 102
 103 #define gic_data_rdist()                (raw_cpu_ptr(gic_rdists->rdist))
 104 #define gic_data_rdist_rd_base()        (gic_data_rdist()->rd_base)
 105
 106 static struct its_collection *dev_event_to_col(struct its_device *its_dev,
 107                                                u32 event)
 108 {
 109         struct its_node *its = its_dev->its;
 110
 111         return its->collections + its_dev->event_map.col_map[event];
 112 }
 113
 114 /*
 115  * ITS command descriptors - parameters to be encoded in a command
 116  * block.
 117  */
 118 struct its_cmd_desc {
 119         union {
 120                 struct {
 121                         struct its_device *dev;
 122                         u32 event_id;
 123                 } its_inv_cmd;
 124
 125                 struct {
 126                         struct its_device *dev;
 127                         u32 event_id;
 128                 } its_int_cmd;
 129
 130                 struct {
 131                         struct its_device *dev;
 132                         int valid;
 133                 } its_mapd_cmd;
 134
 135                 struct {
 136                         struct its_collection *col;
 137                         int valid;
 138                 } its_mapc_cmd;
 139
 140                 struct {
 141                         struct its_device *dev;
 142                         u32 phys_id;
 143                         u32 event_id;
 144                 } its_mapvi_cmd;
 145
 146                 struct {
 147                         struct its_device *dev;
 148                         struct its_collection *col;
 149                         u32 event_id;
 150                 } its_movi_cmd;
 151
 152                 struct {
 153                         struct its_device *dev;
 154                         u32 event_id;
 155                 } its_discard_cmd;
 156
 157                 struct {
 158                         struct its_collection *col;
 159                 } its_invall_cmd;
 160         };
 161 };
 162
 163 /*
 164  * The ITS command block, which is what the ITS actually parses.
 165  */
 166 struct its_cmd_block {
 167         u64     raw_cmd[4];
 168 };
 169
 170 #define ITS_CMD_QUEUE_SZ                SZ_64K
 171 #define ITS_CMD_QUEUE_NR_ENTRIES        (ITS_CMD_QUEUE_SZ / sizeof(struct its_cmd_block))
 172
 173 typedef struct its_collection *(*its_cmd_builder_t)(struct its_cmd_block *,
 174                                                     struct its_cmd_desc *);
 175
 176 static void its_encode_cmd(struct its_cmd_block *cmd, u8 cmd_nr)
 177 {
 178         cmd->raw_cmd[0] &= ~0xffUL;
 179         cmd->raw_cmd[0] |= cmd_nr;
 180 }
 181
 182 static void its_encode_devid(struct its_cmd_block *cmd, u32 devid)
 183 {
 184         cmd->raw_cmd[0] &= BIT_ULL(32) - 1;
 185         cmd->raw_cmd[0] |= ((u64)devid) << 32;
 186 }
 187
 188 static void its_encode_event_id(struct its_cmd_block *cmd, u32 id)
 189 {
 190         cmd->raw_cmd[1] &= ~0xffffffffUL;
 191         cmd->raw_cmd[1] |= id;
 192 }
 193
 194 static void its_encode_phys_id(struct its_cmd_block *cmd, u32 phys_id)
 195 {
 196         cmd->raw_cmd[1] &= 0xffffffffUL;
 197         cmd->raw_cmd[1] |= ((u64)phys_id) << 32;
 198 }
 199
 200 static void its_encode_size(struct its_cmd_block *cmd, u8 size)
 201 {
 202         cmd->raw_cmd[1] &= ~0x1fUL;
 203         cmd->raw_cmd[1] |= size & 0x1f;
 204 }
 205
 206 static void its_encode_itt(struct its_cmd_block *cmd, u64 itt_addr)
 207 {
 208         cmd->raw_cmd[2] &= ~0xffffffffffffUL;
 209         cmd->raw_cmd[2] |= itt_addr & 0xffffffffff00UL;
 210 }
 211
 212 static void its_encode_valid(struct its_cmd_block *cmd, int valid)
 213 {
 214         cmd->raw_cmd[2] &= ~(1UL << 63);
 215         cmd->raw_cmd[2] |= ((u64)!!valid) << 63;
 216 }
 217
 218 static void its_encode_target(struct its_cmd_block *cmd, u64 target_addr)
 219 {
 220         cmd->raw_cmd[2] &= ~(0xffffffffUL << 16);
 221         cmd->raw_cmd[2] |= (target_addr & (0xffffffffUL << 16));
 222 }
 223
 224 static void its_encode_collection(struct its_cmd_block *cmd, u16 col)
 225 {
 226         cmd->raw_cmd[2] &= ~0xffffUL;
 227         cmd->raw_cmd[2] |= col;
 228 }
 229
 230 static inline void its_fixup_cmd(struct its_cmd_block *cmd)
 231 {
 232         /* Let's fixup BE commands */
 233         cmd->raw_cmd[0] = cpu_to_le64(cmd->raw_cmd[0]);
 234         cmd->raw_cmd[1] = cpu_to_le64(cmd->raw_cmd[1]);
 235         cmd->raw_cmd[2] = cpu_to_le64(cmd->raw_cmd[2]);
 236         cmd->raw_cmd[3] = cpu_to_le64(cmd->raw_cmd[3]);
 237 }
 238
 239 static struct its_collection *its_build_mapd_cmd(struct its_cmd_block *cmd,
 240                                                  struct its_cmd_desc *desc)
 241 {
 242         unsigned long itt_addr;
 243         u8 size = ilog2(desc->its_mapd_cmd.dev->nr_ites);
 244
 245         itt_addr = virt_to_phys(desc->its_mapd_cmd.dev->itt);
 246         itt_addr = ALIGN(itt_addr, ITS_ITT_ALIGN);
 247
 248         its_encode_cmd(cmd, GITS_CMD_MAPD);
 249         its_encode_devid(cmd, desc->its_mapd_cmd.dev->device_id);
 250         its_encode_size(cmd, size - 1);
 251         its_encode_itt(cmd, itt_addr);
 252         its_encode_valid(cmd, desc->its_mapd_cmd.valid);
 253
 254         its_fixup_cmd(cmd);
 255
 256         return NULL;
 257 }
 258
 259 static struct its_collection *its_build_mapc_cmd(struct its_cmd_block *cmd,
 260                                                  struct its_cmd_desc *desc)
 261 {
 262         its_encode_cmd(cmd, GITS_CMD_MAPC);
 263         its_encode_collection(cmd, desc->its_mapc_cmd.col->col_id);
 264         its_encode_target(cmd, desc->its_mapc_cmd.col->target_address);
 265         its_encode_valid(cmd, desc->its_mapc_cmd.valid);
 266
 267         its_fixup_cmd(cmd);
 268
 269         return desc->its_mapc_cmd.col;
 270 }
 271
 272 static struct its_collection *its_build_mapvi_cmd(struct its_cmd_block *cmd,
 273                                                   struct its_cmd_desc *desc)
 274 {
 275         struct its_collection *col;
 276
 277         col = dev_event_to_col(desc->its_mapvi_cmd.dev,
 278                                desc->its_mapvi_cmd.event_id);
 279
 280         its_encode_cmd(cmd, GITS_CMD_MAPVI);
 281         its_encode_devid(cmd, desc->its_mapvi_cmd.dev->device_id);
 282         its_encode_event_id(cmd, desc->its_mapvi_cmd.event_id);
 283         its_encode_phys_id(cmd, desc->its_mapvi_cmd.phys_id);
 284         its_encode_collection(cmd, col->col_id);
 285
 286         its_fixup_cmd(cmd);
 287
 288         return col;
 289 }
 290
 291 static struct its_collection *its_build_movi_cmd(struct its_cmd_block *cmd,
 292                                                  struct its_cmd_desc *desc)
 293 {
 294         struct its_collection *col;
 295
 296         col = dev_event_to_col(desc->its_movi_cmd.dev,
 297                                desc->its_movi_cmd.event_id);
 298
 299         its_encode_cmd(cmd, GITS_CMD_MOVI);
 300         its_encode_devid(cmd, desc->its_movi_cmd.dev->device_id);
 301         its_encode_event_id(cmd, desc->its_movi_cmd.event_id);
 302         its_encode_collection(cmd, desc->its_movi_cmd.col->col_id);
 303
 304         its_fixup_cmd(cmd);
 305
 306         return col;
 307 }
 308
 309 static struct its_collection *its_build_discard_cmd(struct its_cmd_block *cmd,
 310                                                     struct its_cmd_desc *desc)
 311 {
 312         struct its_collection *col;
 313
 314         col = dev_event_to_col(desc->its_discard_cmd.dev,
 315                                desc->its_discard_cmd.event_id);
 316
 317         its_encode_cmd(cmd, GITS_CMD_DISCARD);
 318         its_encode_devid(cmd, desc->its_discard_cmd.dev->device_id);
 319         its_encode_event_id(cmd, desc->its_discard_cmd.event_id);
 320
 321         its_fixup_cmd(cmd);
 322
 323         return col;
 324 }
 325
 326 static struct its_collection *its_build_inv_cmd(struct its_cmd_block *cmd,
 327                                                 struct its_cmd_desc *desc)
 328 {
 329         struct its_collection *col;
 330
 331         col = dev_event_to_col(desc->its_inv_cmd.dev,
 332                                desc->its_inv_cmd.event_id);
 333
 334         its_encode_cmd(cmd, GITS_CMD_INV);
 335         its_encode_devid(cmd, desc->its_inv_cmd.dev->device_id);
 336         its_encode_event_id(cmd, desc->its_inv_cmd.event_id);
 337
 338         its_fixup_cmd(cmd);
 339
 340         return col;
 341 }
 342
 343 static struct its_collection *its_build_invall_cmd(struct its_cmd_block *cmd,
 344                                                    struct its_cmd_desc *desc)
 345 {
 346         its_encode_cmd(cmd, GITS_CMD_INVALL);
 347         its_encode_collection(cmd, desc->its_mapc_cmd.col->col_id);
 348
 349         its_fixup_cmd(cmd);
 350
 351         return NULL;
 352 }
 353
 354 static u64 its_cmd_ptr_to_offset(struct its_node *its,
 355                                  struct its_cmd_block *ptr)
 356 {
 357         return (ptr - its->cmd_base) * sizeof(*ptr);
 358 }
 359
 360 static int its_queue_full(struct its_node *its)
 361 {
 362         int widx;
 363         int ridx;
 364
 365         widx = its->cmd_write - its->cmd_base;
 366         ridx = readl_relaxed(its->base + GITS_CREADR) / sizeof(struct its_cmd_block);
 367
 368         /* This is incredibly unlikely to happen, unless the ITS locks up. */
 369         if (((widx + 1) % ITS_CMD_QUEUE_NR_ENTRIES) == ridx)
 370                 return 1;
 371
 372         return 0;
 373 }
 374
 375 static struct its_cmd_block *its_allocate_entry(struct its_node *its)
 376 {
 377         struct its_cmd_block *cmd;
 378         u32 count = 1000000;    /* 1s! */
 379
 380         while (its_queue_full(its)) {
 381                 count--;
 382                 if (!count) {
 383                         pr_err_ratelimited("ITS queue not draining\n");
 384                         return NULL;
 385                 }
 386                 cpu_relax();
 387                 udelay(1);
 388         }
 389
 390         cmd = its->cmd_write++;
 391
 392         /* Handle queue wrapping */
 393         if (its->cmd_write == (its->cmd_base + ITS_CMD_QUEUE_NR_ENTRIES))
 394                 its->cmd_write = its->cmd_base;
 395
 396         return cmd;
 397 }
 398
 399 static struct its_cmd_block *its_post_commands(struct its_node *its)
 400 {
 401         u64 wr = its_cmd_ptr_to_offset(its, its->cmd_write);
 402
 403         writel_relaxed(wr, its->base + GITS_CWRITER);
 404
 405         return its->cmd_write;
 406 }
 407
 408 static void its_flush_cmd(struct its_node *its, struct its_cmd_block *cmd)
 409 {
 410         /*
 411          * Make sure the commands written to memory are observable by
 412          * the ITS.
 413          */
 414         if (its->flags & ITS_FLAGS_CMDQ_NEEDS_FLUSHING)
 415                 __flush_dcache_area(cmd, sizeof(*cmd));
 416         else
 417                 dsb(ishst);
 418 }
 419
 420 static void its_wait_for_range_completion(struct its_node *its,
 421                                           struct its_cmd_block *from,
 422                                           struct its_cmd_block *to)
 423 {
 424         u64 rd_idx, from_idx, to_idx;
 425         u32 count = 1000000;    /* 1s! */
 426
 427         from_idx = its_cmd_ptr_to_offset(its, from);
 428         to_idx = its_cmd_ptr_to_offset(its, to);
 429
 430         while (1) {
 431                 rd_idx = readl_relaxed(its->base + GITS_CREADR);
 432                 if (rd_idx >= to_idx || rd_idx < from_idx)
 433                         break;
 434
 435                 count--;
 436                 if (!count) {
 437                         pr_err_ratelimited("ITS queue timeout\n");
 438                         return;
 439                 }
 440                 cpu_relax();
 441                 udelay(1);
 442         }
 443 }
 444
 445 static void its_send_single_command(struct its_node *its,
 446                                     its_cmd_builder_t builder,
 447                                     struct its_cmd_desc *desc)
 448 {
 449         struct its_cmd_block *cmd, *sync_cmd, *next_cmd;
 450         struct its_collection *sync_col;
 451         unsigned long flags;
 452
 453         raw_spin_lock_irqsave(&its->lock, flags);
 454
 455         cmd = its_allocate_entry(its);
 456         if (!cmd) {             /* We're soooooo screewed... */
 457                 pr_err_ratelimited("ITS can't allocate, dropping command\n");
 458                 raw_spin_unlock_irqrestore(&its->lock, flags);
 459                 return;
 460         }
 461         sync_col = builder(cmd, desc);
 462         its_flush_cmd(its, cmd);
 463
 464         if (sync_col) {
 465                 sync_cmd = its_allocate_entry(its);
 466                 if (!sync_cmd) {
 467                         pr_err_ratelimited("ITS can't SYNC, skipping\n");
 468                         goto post;
 469                 }
 470                 its_encode_cmd(sync_cmd, GITS_CMD_SYNC);
 471                 its_encode_target(sync_cmd, sync_col->target_address);
 472                 its_fixup_cmd(sync_cmd);
 473                 its_flush_cmd(its, sync_cmd);
 474         }
 475
 476 post:
 477         next_cmd = its_post_commands(its);
 478         raw_spin_unlock_irqrestore(&its->lock, flags);
 479
 480         its_wait_for_range_completion(its, cmd, next_cmd);
 481 }
 482
 483 static void its_send_inv(struct its_device *dev, u32 event_id)
 484 {
 485         struct its_cmd_desc desc;
 486
 487         desc.its_inv_cmd.dev = dev;
 488         desc.its_inv_cmd.event_id = event_id;
 489
 490         its_send_single_command(dev->its, its_build_inv_cmd, &desc);
 491 }
 492
 493 static void its_send_mapd(struct its_device *dev, int valid)
 494 {
 495         struct its_cmd_desc desc;
 496
 497         desc.its_mapd_cmd.dev = dev;
 498         desc.its_mapd_cmd.valid = !!valid;
 499
 500         its_send_single_command(dev->its, its_build_mapd_cmd, &desc);
 501 }
 502
 503 static void its_send_mapc(struct its_node *its, struct its_collection *col,
 504                           int valid)
 505 {
 506         struct its_cmd_desc desc;
 507
 508         desc.its_mapc_cmd.col = col;
 509         desc.its_mapc_cmd.valid = !!valid;
 510
 511         its_send_single_command(its, its_build_mapc_cmd, &desc);
 512 }
 513
 514 static void its_send_mapvi(struct its_device *dev, u32 irq_id, u32 id)
 515 {
 516         struct its_cmd_desc desc;
 517
 518         desc.its_mapvi_cmd.dev = dev;
 519         desc.its_mapvi_cmd.phys_id = irq_id;
 520         desc.its_mapvi_cmd.event_id = id;
 521
 522         its_send_single_command(dev->its, its_build_mapvi_cmd, &desc);
 523 }
 524
 525 static void its_send_movi(struct its_device *dev,
 526                           struct its_collection *col, u32 id)
 527 {
 528         struct its_cmd_desc desc;
 529
 530         desc.its_movi_cmd.dev = dev;
 531         desc.its_movi_cmd.col = col;
 532         desc.its_movi_cmd.event_id = id;
 533
 534         its_send_single_command(dev->its, its_build_movi_cmd, &desc);
 535 }
 536
 537 static void its_send_discard(struct its_device *dev, u32 id)
 538 {
 539         struct its_cmd_desc desc;
 540
 541         desc.its_discard_cmd.dev = dev;
 542         desc.its_discard_cmd.event_id = id;
 543
 544         its_send_single_command(dev->its, its_build_discard_cmd, &desc);
 545 }
 546
 547 static void its_send_invall(struct its_node *its, struct its_collection *col)
 548 {
 549         struct its_cmd_desc desc;
 550
 551         desc.its_invall_cmd.col = col;
 552
 553         its_send_single_command(its, its_build_invall_cmd, &desc);
 554 }
 555
 556 /*
 557  * irqchip functions - assumes MSI, mostly.
 558  */
 559
 560 static inline u32 its_get_event_id(struct irq_data *d)
 561 {
 562         struct its_device *its_dev = irq_data_get_irq_chip_data(d);
 563         return d->hwirq - its_dev->event_map.lpi_base;
 564 }
 565
 566 static void lpi_set_config(struct irq_data *d, bool enable)
 567 {
 568         struct its_device *its_dev = irq_data_get_irq_chip_data(d);
 569         irq_hw_number_t hwirq = d->hwirq;
 570         u32 id = its_get_event_id(d);
 571         u8 *cfg = page_address(gic_rdists->prop_page) + hwirq - 8192;
 572
 573         if (enable)
 574                 *cfg |= LPI_PROP_ENABLED;
 575         else
 576                 *cfg &= ~LPI_PROP_ENABLED;
 577
 578         /*
 579          * Make the above write visible to the redistributors.
 580          * And yes, we're flushing exactly: One. Single. Byte.
 581          * Humpf...
 582          */
 583         if (gic_rdists->flags & RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING)
 584                 __flush_dcache_area(cfg, sizeof(*cfg));
 585         else
 586                 dsb(ishst);
 587         its_send_inv(its_dev, id);
 588 }
 589
 590 static void its_mask_irq(struct irq_data *d)
 591 {
 592         lpi_set_config(d, false);
 593 }
 594
 595 static void its_unmask_irq(struct irq_data *d)
 596 {
 597         lpi_set_config(d, true);
 598 }
 599
 600 static void its_eoi_irq(struct irq_data *d)
 601 {
 602         gic_write_eoir(d->hwirq);
 603 }
 604
 605 static int its_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
 606                             bool force)
 607 {
 608         unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
 609         struct its_device *its_dev = irq_data_get_irq_chip_data(d);
 610         struct its_collection *target_col;
 611         u32 id = its_get_event_id(d);
 612
 613         if (cpu >= nr_cpu_ids)
 614                 return -EINVAL;
 615
 616         target_col = &its_dev->its->collections[cpu];
 617         its_send_movi(its_dev, target_col, id);
 618         its_dev->event_map.col_map[id] = cpu;
 619
 620         return IRQ_SET_MASK_OK_DONE;
 621 }
 622
 623 static void its_irq_compose_msi_msg(struct irq_data *d, struct msi_msg *msg)
 624 {
 625         struct its_device *its_dev = irq_data_get_irq_chip_data(d);
 626         struct its_node *its;
 627         u64 addr;
 628
 629         its = its_dev->its;
 630         addr = its->phys_base + GITS_TRANSLATER;
 631
 632         msg->address_lo         = addr & ((1UL << 32) - 1);
 633         msg->address_hi         = addr >> 32;
 634         msg->data               = its_get_event_id(d);
 635 }
 636
 637 static struct irq_chip its_irq_chip = {
 638         .name                   = "ITS",
 639         .irq_mask               = its_mask_irq,
 640         .irq_unmask             = its_unmask_irq,
 641         .irq_eoi                = its_eoi_irq,
 642         .irq_set_affinity       = its_set_affinity,
 643         .irq_compose_msi_msg    = its_irq_compose_msi_msg,
 644 };
 645
 646 static void its_mask_msi_irq(struct irq_data *d)
 647 {
 648         pci_msi_mask_irq(d);
 649         irq_chip_mask_parent(d);
 650 }
 651
 652 static void its_unmask_msi_irq(struct irq_data *d)
 653 {
 654         pci_msi_unmask_irq(d);
 655         irq_chip_unmask_parent(d);
 656 }
 657
 658 static struct irq_chip its_msi_irq_chip = {
 659         .name                   = "ITS-MSI",
 660         .irq_unmask             = its_unmask_msi_irq,
 661         .irq_mask               = its_mask_msi_irq,
 662         .irq_eoi                = irq_chip_eoi_parent,
 663         .irq_write_msi_msg      = pci_msi_domain_write_msg,
 664 };
 665
 666 /*
 667  * How we allocate LPIs:
 668  *
 669  * The GIC has id_bits bits for interrupt identifiers. From there, we
 670  * must subtract 8192 which are reserved for SGIs/PPIs/SPIs. Then, as
 671  * we allocate LPIs by chunks of 32, we can shift the whole thing by 5
 672  * bits to the right.
 673  *
 674  * This gives us (((1UL << id_bits) - 8192) >> 5) possible allocations.
 675  */
 676 #define IRQS_PER_CHUNK_SHIFT    5
 677 #define IRQS_PER_CHUNK          (1 << IRQS_PER_CHUNK_SHIFT)
 678
 679 static unsigned long *lpi_bitmap;
 680 static u32 lpi_chunks;
 681 static DEFINE_SPINLOCK(lpi_lock);
 682
 683 static int its_lpi_to_chunk(int lpi)
 684 {
 685         return (lpi - 8192) >> IRQS_PER_CHUNK_SHIFT;
 686 }
 687
 688 static int its_chunk_to_lpi(int chunk)
 689 {
 690         return (chunk << IRQS_PER_CHUNK_SHIFT) + 8192;
 691 }
 692
 693 static int its_lpi_init(u32 id_bits)
 694 {
 695         lpi_chunks = its_lpi_to_chunk(1UL << id_bits);
 696
 697         lpi_bitmap = kzalloc(BITS_TO_LONGS(lpi_chunks) * sizeof(long),
 698                              GFP_KERNEL);
 699         if (!lpi_bitmap) {
 700                 lpi_chunks = 0;
 701                 return -ENOMEM;
 702         }
 703
 704         pr_info("ITS: Allocated %d chunks for LPIs\n", (int)lpi_chunks);
 705         return 0;
 706 }
 707
 708 static unsigned long *its_lpi_alloc_chunks(int nr_irqs, int *base, int *nr_ids)
 709 {
 710         unsigned long *bitmap = NULL;
 711         int chunk_id;
 712         int nr_chunks;
 713         int i;
 714
 715         nr_chunks = DIV_ROUND_UP(nr_irqs, IRQS_PER_CHUNK);
 716
 717         spin_lock(&lpi_lock);
 718
 719         do {
 720                 chunk_id = bitmap_find_next_zero_area(lpi_bitmap, lpi_chunks,
 721                                                       0, nr_chunks, 0);
 722                 if (chunk_id < lpi_chunks)
 723                         break;
 724
 725                 nr_chunks--;
 726         } while (nr_chunks > 0);
 727
 728         if (!nr_chunks)
 729                 goto out;
 730
 731         bitmap = kzalloc(BITS_TO_LONGS(nr_chunks * IRQS_PER_CHUNK) * sizeof (long),
 732                          GFP_ATOMIC);
 733         if (!bitmap)
 734                 goto out;
 735
 736         for (i = 0; i < nr_chunks; i++)
 737                 set_bit(chunk_id + i, lpi_bitmap);
 738
 739         *base = its_chunk_to_lpi(chunk_id);
 740         *nr_ids = nr_chunks * IRQS_PER_CHUNK;
 741
 742 out:
 743         spin_unlock(&lpi_lock);
 744
 745         return bitmap;
 746 }
 747
 748 static void its_lpi_free(struct event_lpi_map *map)
 749 {
 750         int base = map->lpi_base;
 751         int nr_ids = map->nr_lpis;
 752         int lpi;
 753
 754         spin_lock(&lpi_lock);
 755
 756         for (lpi = base; lpi < (base + nr_ids); lpi += IRQS_PER_CHUNK) {
 757                 int chunk = its_lpi_to_chunk(lpi);
 758                 BUG_ON(chunk > lpi_chunks);
 759                 if (test_bit(chunk, lpi_bitmap)) {
 760                         clear_bit(chunk, lpi_bitmap);
 761                 } else {
 762                         pr_err("Bad LPI chunk %d\n", chunk);
 763                 }
 764         }
 765
 766         spin_unlock(&lpi_lock);
 767
 768         kfree(map->lpi_map);
 769         kfree(map->col_map);
 770 }
 771
 772 /*
 773  * We allocate 64kB for PROPBASE. That gives us at most 64K LPIs to
 774  * deal with (one configuration byte per interrupt). PENDBASE has to
 775  * be 64kB aligned (one bit per LPI, plus 8192 bits for SPI/PPI/SGI).
 776  */
 777 #define LPI_PROPBASE_SZ         SZ_64K
 778 #define LPI_PENDBASE_SZ         (LPI_PROPBASE_SZ / 8 + SZ_1K)
 779
 780 /*
 781  * This is how many bits of ID we need, including the useless ones.
 782  */
 783 #define LPI_NRBITS              ilog2(LPI_PROPBASE_SZ + SZ_8K)
 784
 785 #define LPI_PROP_DEFAULT_PRIO   0xa0
 786
 787 static int __init its_alloc_lpi_tables(void)
 788 {
 789         phys_addr_t paddr;
 790
 791         gic_rdists->prop_page = alloc_pages(GFP_NOWAIT,
 792                                            get_order(LPI_PROPBASE_SZ));
 793         if (!gic_rdists->prop_page) {
 794                 pr_err("Failed to allocate PROPBASE\n");
 795                 return -ENOMEM;
 796         }
 797
 798         paddr = page_to_phys(gic_rdists->prop_page);
 799         pr_info("GIC: using LPI property table @%pa\n", &paddr);
 800
 801         /* Priority 0xa0, Group-1, disabled */
 802         memset(page_address(gic_rdists->prop_page),
 803                LPI_PROP_DEFAULT_PRIO | LPI_PROP_GROUP1,
 804                LPI_PROPBASE_SZ);
 805
 806         /* Make sure the GIC will observe the written configuration */
 807         __flush_dcache_area(page_address(gic_rdists->prop_page), LPI_PROPBASE_SZ);
 808
 809         return 0;
 810 }
 811
 812 static const char *its_base_type_string[] = {
 813         [GITS_BASER_TYPE_DEVICE]        = "Devices",
 814         [GITS_BASER_TYPE_VCPU]          = "Virtual CPUs",
 815         [GITS_BASER_TYPE_CPU]           = "Physical CPUs",
 816         [GITS_BASER_TYPE_COLLECTION]    = "Interrupt Collections",
 817         [GITS_BASER_TYPE_RESERVED5]     = "Reserved (5)",
 818         [GITS_BASER_TYPE_RESERVED6]     = "Reserved (6)",
 819         [GITS_BASER_TYPE_RESERVED7]     = "Reserved (7)",
 820 };
 821
 822 static void its_free_tables(struct its_node *its)
 823 {
 824         int i;
 825
 826         for (i = 0; i < GITS_BASER_NR_REGS; i++) {
 827                 if (its->tables[i]) {
 828                         free_page((unsigned long)its->tables[i]);
 829                         its->tables[i] = NULL;
 830                 }
 831         }
 832 }
 833
 834 static int its_alloc_tables(struct its_node *its)
 835 {
 836         int err;
 837         int i;
 838         int psz = SZ_64K;
 839         u64 shr = GITS_BASER_InnerShareable;
 840         u64 cache = GITS_BASER_WaWb;
 841
 842         for (i = 0; i < GITS_BASER_NR_REGS; i++) {
 843                 u64 val = readq_relaxed(its->base + GITS_BASER + i * 8);
 844                 u64 type = GITS_BASER_TYPE(val);
 845                 u64 entry_size = GITS_BASER_ENTRY_SIZE(val);
 846                 int order = get_order(psz);
 847                 int alloc_size;
 848                 u64 tmp;
 849                 void *base;
 850
 851                 if (type == GITS_BASER_TYPE_NONE)
 852                         continue;
 853
 854                 /*
 855                  * Allocate as many entries as required to fit the
 856                  * range of device IDs that the ITS can grok... The ID
 857                  * space being incredibly sparse, this results in a
 858                  * massive waste of memory.
 859                  *
 860                  * For other tables, only allocate a single page.
 861                  */
 862                 if (type == GITS_BASER_TYPE_DEVICE) {
 863                         u64 typer = readq_relaxed(its->base + GITS_TYPER);
 864                         u32 ids = GITS_TYPER_DEVBITS(typer);
 865
 866                         /*
 867                          * 'order' was initialized earlier to the default page
 868                          * granule of the the ITS.  We can't have an allocation
 869                          * smaller than that.  If the requested allocation
 870                          * is smaller, round up to the default page granule.
 871                          */
 872                         order = max(get_order((1UL << ids) * entry_size),
 873                                     order);
 874                         if (order >= MAX_ORDER) {
 875                                 order = MAX_ORDER - 1;
 876                                 pr_warn("%s: Device Table too large, reduce its page order to %u\n",
 877                                         its->msi_chip.of_node->full_name, order);
 878                         }
 879                 }
 880
 881                 alloc_size = (1 << order) * PAGE_SIZE;
 882                 base = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
 883                 if (!base) {
 884                         err = -ENOMEM;
 885                         goto out_free;
 886                 }
 887
 888                 its->tables[i] = base;
 889
 890 retry_baser:
 891                 val = (virt_to_phys(base)                                |
 892                        (type << GITS_BASER_TYPE_SHIFT)                   |
 893                        ((entry_size - 1) << GITS_BASER_ENTRY_SIZE_SHIFT) |
 894                        cache                                             |
 895                        shr                                               |
 896                        GITS_BASER_VALID);
 897
 898                 switch (psz) {
 899                 case SZ_4K:
 900                         val |= GITS_BASER_PAGE_SIZE_4K;
 901                         break;
 902                 case SZ_16K:
 903                         val |= GITS_BASER_PAGE_SIZE_16K;
 904                         break;
 905                 case SZ_64K:
 906                         val |= GITS_BASER_PAGE_SIZE_64K;
 907                         break;
 908                 }
 909
 910                 val |= (alloc_size / psz) - 1;
 911
 912                 writeq_relaxed(val, its->base + GITS_BASER + i * 8);
 913                 tmp = readq_relaxed(its->base + GITS_BASER + i * 8);
 914
 915                 if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) {
 916                         /*
 917                          * Shareability didn't stick. Just use
 918                          * whatever the read reported, which is likely
 919                          * to be the only thing this redistributor
 920                          * supports. If that's zero, make it
 921                          * non-cacheable as well.
 922                          */
 923                         shr = tmp & GITS_BASER_SHAREABILITY_MASK;
 924                         if (!shr)
 925                                 cache = GITS_BASER_nC;
 926                         goto retry_baser;
 927                 }
 928
 929                 if ((val ^ tmp) & GITS_BASER_PAGE_SIZE_MASK) {
 930                         /*
 931                          * Page size didn't stick. Let's try a smaller
 932                          * size and retry. If we reach 4K, then
 933                          * something is horribly wrong...
 934                          */
 935                         switch (psz) {
 936                         case SZ_16K:
 937                                 psz = SZ_4K;
 938                                 goto retry_baser;
 939                         case SZ_64K:
 940                                 psz = SZ_16K;
 941                                 goto retry_baser;
 942                         }
 943                 }
 944
 945                 if (val != tmp) {
 946                         pr_err("ITS: %s: GITS_BASER%d doesn't stick: %lx %lx\n",
 947                                its->msi_chip.of_node->full_name, i,
 948                                (unsigned long) val, (unsigned long) tmp);
 949                         err = -ENXIO;
 950                         goto out_free;
 951                 }
 952
 953                 pr_info("ITS: allocated %d %s @%lx (psz %dK, shr %d)\n",
 954                         (int)(alloc_size / entry_size),
 955                         its_base_type_string[type],
 956                         (unsigned long)virt_to_phys(base),
 957                         psz / SZ_1K, (int)shr >> GITS_BASER_SHAREABILITY_SHIFT);
 958         }
 959
 960         return 0;
 961
 962 out_free:
 963         its_free_tables(its);
 964
 965         return err;
 966 }
 967
 968 static int its_alloc_collections(struct its_node *its)
 969 {
 970         its->collections = kzalloc(nr_cpu_ids * sizeof(*its->collections),
 971                                    GFP_KERNEL);
 972         if (!its->collections)
 973                 return -ENOMEM;
 974
 975         return 0;
 976 }
 977
 978 static void its_cpu_init_lpis(void)
 979 {
 980         void __iomem *rbase = gic_data_rdist_rd_base();
 981         struct page *pend_page;
 982         u64 val, tmp;
 983
 984         /* If we didn't allocate the pending table yet, do it now */
 985         pend_page = gic_data_rdist()->pend_page;
 986         if (!pend_page) {
 987                 phys_addr_t paddr;
 988                 /*
 989                  * The pending pages have to be at least 64kB aligned,
 990                  * hence the 'max(LPI_PENDBASE_SZ, SZ_64K)' below.
 991                  */
 992                 pend_page = alloc_pages(GFP_NOWAIT | __GFP_ZERO,
 993                                         get_order(max(LPI_PENDBASE_SZ, SZ_64K)));
 994                 if (!pend_page) {
 995                         pr_err("Failed to allocate PENDBASE for CPU%d\n",
 996                                smp_processor_id());
 997                         return;
 998                 }
 999
1000                 /* Make sure the GIC will observe the zero-ed page */
1001                 __flush_dcache_area(page_address(pend_page), LPI_PENDBASE_SZ);
1002
1003                 paddr = page_to_phys(pend_page);
1004                 pr_info("CPU%d: using LPI pending table @%pa\n",
1005                         smp_processor_id(), &paddr);
1006                 gic_data_rdist()->pend_page = pend_page;
1007         }
1008
1009         /* Disable LPIs */
1010         val = readl_relaxed(rbase + GICR_CTLR);
1011         val &= ~GICR_CTLR_ENABLE_LPIS;
1012         writel_relaxed(val, rbase + GICR_CTLR);
1013
1014         /*
1015          * Make sure any change to the table is observable by the GIC.
1016          */
1017         dsb(sy);
1018
1019         /* set PROPBASE */
1020         val = (page_to_phys(gic_rdists->prop_page) |
1021                GICR_PROPBASER_InnerShareable |
1022                GICR_PROPBASER_WaWb |
1023                ((LPI_NRBITS - 1) & GICR_PROPBASER_IDBITS_MASK));
1024
1025         writeq_relaxed(val, rbase + GICR_PROPBASER);
1026         tmp = readq_relaxed(rbase + GICR_PROPBASER);
1027
1028         if ((tmp ^ val) & GICR_PROPBASER_SHAREABILITY_MASK) {
1029                 if (!(tmp & GICR_PROPBASER_SHAREABILITY_MASK)) {
1030                         /*
1031                          * The HW reports non-shareable, we must
1032                          * remove the cacheability attributes as
1033                          * well.
1034                          */
1035                         val &= ~(GICR_PROPBASER_SHAREABILITY_MASK |
1036                                  GICR_PROPBASER_CACHEABILITY_MASK);
1037                         val |= GICR_PROPBASER_nC;
1038                         writeq_relaxed(val, rbase + GICR_PROPBASER);
1039                 }
1040                 pr_info_once("GIC: using cache flushing for LPI property table\n");
1041                 gic_rdists->flags |= RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING;
1042         }
1043
1044         /* set PENDBASE */
1045         val = (page_to_phys(pend_page) |
1046                GICR_PENDBASER_InnerShareable |
1047                GICR_PENDBASER_WaWb);
1048
1049         writeq_relaxed(val, rbase + GICR_PENDBASER);
1050         tmp = readq_relaxed(rbase + GICR_PENDBASER);
1051
1052         if (!(tmp & GICR_PENDBASER_SHAREABILITY_MASK)) {
1053                 /*
1054                  * The HW reports non-shareable, we must remove the
1055                  * cacheability attributes as well.
1056                  */
1057                 val &= ~(GICR_PENDBASER_SHAREABILITY_MASK |
1058                          GICR_PENDBASER_CACHEABILITY_MASK);
1059                 val |= GICR_PENDBASER_nC;
1060                 writeq_relaxed(val, rbase + GICR_PENDBASER);
1061         }
1062
1063         /* Enable LPIs */
1064         val = readl_relaxed(rbase + GICR_CTLR);
1065         val |= GICR_CTLR_ENABLE_LPIS;
1066         writel_relaxed(val, rbase + GICR_CTLR);
1067
1068         /* Make sure the GIC has seen the above */
1069         dsb(sy);
1070 }
1071
1072 static void its_cpu_init_collection(void)
1073 {
1074         struct its_node *its;
1075         int cpu;
1076
1077         spin_lock(&its_lock);
1078         cpu = smp_processor_id();
1079
1080         list_for_each_entry(its, &its_nodes, entry) {
1081                 u64 target;
1082
1083                 /*
1084                  * We now have to bind each collection to its target
1085                  * redistributor.
1086                  */
1087                 if (readq_relaxed(its->base + GITS_TYPER) & GITS_TYPER_PTA) {
1088                         /*
1089                          * This ITS wants the physical address of the
1090                          * redistributor.
1091                          */
1092                         target = gic_data_rdist()->phys_base;
1093                 } else {
1094                         /*
1095                          * This ITS wants a linear CPU number.
1096                          */
1097                         target = readq_relaxed(gic_data_rdist_rd_base() + GICR_TYPER);
1098                         target = GICR_TYPER_CPU_NUMBER(target) << 16;
1099                 }
1100
1101                 /* Perform collection mapping */
1102                 its->collections[cpu].target_address = target;
1103                 its->collections[cpu].col_id = cpu;
1104
1105                 its_send_mapc(its, &its->collections[cpu], 1);
1106                 its_send_invall(its, &its->collections[cpu]);
1107         }
1108
1109         spin_unlock(&its_lock);
1110 }
1111
1112 static struct its_device *its_find_device(struct its_node *its, u32 dev_id)
1113 {
1114         struct its_device *its_dev = NULL, *tmp;
1115         unsigned long flags;
1116
1117         raw_spin_lock_irqsave(&its->lock, flags);
1118
1119         list_for_each_entry(tmp, &its->its_device_list, entry) {
1120                 if (tmp->device_id == dev_id) {
1121                         its_dev = tmp;
1122                         break;
1123                 }
1124         }
1125
1126         raw_spin_unlock_irqrestore(&its->lock, flags);
1127
1128         return its_dev;
1129 }
1130
1131 static struct its_device *its_create_device(struct its_node *its, u32 dev_id,
1132                                             int nvecs)
1133 {
1134         struct its_device *dev;
1135         unsigned long *lpi_map;
1136         unsigned long flags;
1137         u16 *col_map = NULL;
1138         void *itt;
1139         int lpi_base;
1140         int nr_lpis;
1141         int nr_ites;
1142         int sz;
1143
1144         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1145         /*
1146          * At least one bit of EventID is being used, hence a minimum
1147          * of two entries. No, the architecture doesn't let you
1148          * express an ITT with a single entry.
1149          */
1150         nr_ites = max(2UL, roundup_pow_of_two(nvecs));
1151         sz = nr_ites * its->ite_size;
1152         sz = max(sz, ITS_ITT_ALIGN) + ITS_ITT_ALIGN - 1;
1153         itt = kzalloc(sz, GFP_KERNEL);
1154         lpi_map = its_lpi_alloc_chunks(nvecs, &lpi_base, &nr_lpis);
1155         if (lpi_map)
1156                 col_map = kzalloc(sizeof(*col_map) * nr_lpis, GFP_KERNEL);
1157
1158         if (!dev || !itt || !lpi_map || !col_map) {
1159                 kfree(dev);
1160                 kfree(itt);
1161                 kfree(lpi_map);
1162                 kfree(col_map);
1163                 return NULL;
1164         }
1165
1166         dev->its = its;
1167         dev->itt = itt;
1168         dev->nr_ites = nr_ites;
1169         dev->event_map.lpi_map = lpi_map;
1170         dev->event_map.col_map = col_map;
1171         dev->event_map.lpi_base = lpi_base;
1172         dev->event_map.nr_lpis = nr_lpis;
1173         dev->device_id = dev_id;
1174         INIT_LIST_HEAD(&dev->entry);
1175
1176         raw_spin_lock_irqsave(&its->lock, flags);
1177         list_add(&dev->entry, &its->its_device_list);
1178         raw_spin_unlock_irqrestore(&its->lock, flags);
1179
1180         /* Map device to its ITT */
1181         its_send_mapd(dev, 1);
1182
1183         return dev;
1184 }
1185
1186 static void its_free_device(struct its_device *its_dev)
1187 {
1188         unsigned long flags;
1189
1190         raw_spin_lock_irqsave(&its_dev->its->lock, flags);
1191         list_del(&its_dev->entry);
1192         raw_spin_unlock_irqrestore(&its_dev->its->lock, flags);
1193         kfree(its_dev->itt);
1194         kfree(its_dev);
1195 }
1196
1197 static int its_alloc_device_irq(struct its_device *dev, irq_hw_number_t *hwirq)
1198 {
1199         int idx;
1200
1201         idx = find_first_zero_bit(dev->event_map.lpi_map,
1202                                   dev->event_map.nr_lpis);
1203         if (idx == dev->event_map.nr_lpis)
1204                 return -ENOSPC;
1205
1206         *hwirq = dev->event_map.lpi_base + idx;
1207         set_bit(idx, dev->event_map.lpi_map);
1208
1209         return 0;
1210 }
1211
1212 struct its_pci_alias {
1213         struct pci_dev  *pdev;
1214         u32             dev_id;
1215         u32             count;
1216 };
1217
1218 static int its_pci_msi_vec_count(struct pci_dev *pdev)
1219 {
1220         int msi, msix;
1221
1222         msi = max(pci_msi_vec_count(pdev), 0);
1223         msix = max(pci_msix_vec_count(pdev), 0);
1224
1225         return max(msi, msix);
1226 }
1227
1228 static int its_get_pci_alias(struct pci_dev *pdev, u16 alias, void *data)
1229 {
1230         struct its_pci_alias *dev_alias = data;
1231
1232         dev_alias->dev_id = alias;
1233         if (pdev != dev_alias->pdev)
1234                 dev_alias->count += its_pci_msi_vec_count(dev_alias->pdev);
1235
1236         return 0;
1237 }
1238
1239 static int its_msi_prepare(struct irq_domain *domain, struct device *dev,
1240                            int nvec, msi_alloc_info_t *info)
1241 {
1242         struct pci_dev *pdev;
1243         struct its_node *its;
1244         struct its_device *its_dev;
1245         struct its_pci_alias dev_alias;
1246
1247         if (!dev_is_pci(dev))
1248                 return -EINVAL;
1249
1250         pdev = to_pci_dev(dev);
1251         dev_alias.pdev = pdev;
1252         dev_alias.count = nvec;
1253
1254         pci_for_each_dma_alias(pdev, its_get_pci_alias, &dev_alias);
1255         its = domain->parent->host_data;
1256
1257         its_dev = its_find_device(its, dev_alias.dev_id);
1258         if (its_dev) {
1259                 /*
1260                  * We already have seen this ID, probably through
1261                  * another alias (PCI bridge of some sort). No need to
1262                  * create the device.
1263                  */
1264                 dev_dbg(dev, "Reusing ITT for devID %x\n", dev_alias.dev_id);
1265                 goto out;
1266         }
1267
1268         its_dev = its_create_device(its, dev_alias.dev_id, dev_alias.count);
1269         if (!its_dev)
1270                 return -ENOMEM;
1271
1272         dev_dbg(&pdev->dev, "ITT %d entries, %d bits\n",
1273                 dev_alias.count, ilog2(dev_alias.count));
1274 out:
1275         info->scratchpad[0].ptr = its_dev;
1276         info->scratchpad[1].ptr = dev;
1277         return 0;
1278 }
1279
1280 static struct msi_domain_ops its_pci_msi_ops = {
1281         .msi_prepare    = its_msi_prepare,
1282 };
1283
1284 static struct msi_domain_info its_pci_msi_domain_info = {
1285         .flags  = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
1286                    MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX),
1287         .ops    = &its_pci_msi_ops,
1288         .chip   = &its_msi_irq_chip,
1289 };
1290
1291 static int its_irq_gic_domain_alloc(struct irq_domain *domain,
1292                                     unsigned int virq,
1293                                     irq_hw_number_t hwirq)
1294 {
1295         struct of_phandle_args args;
1296
1297         args.np = domain->parent->of_node;
1298         args.args_count = 3;
1299         args.args[0] = GIC_IRQ_TYPE_LPI;
1300         args.args[1] = hwirq;
1301         args.args[2] = IRQ_TYPE_EDGE_RISING;
1302
1303         return irq_domain_alloc_irqs_parent(domain, virq, 1, &args);
1304 }
1305
1306 static int its_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
1307                                 unsigned int nr_irqs, void *args)
1308 {
1309         msi_alloc_info_t *info = args;
1310         struct its_device *its_dev = info->scratchpad[0].ptr;
1311         irq_hw_number_t hwirq;
1312         int err;
1313         int i;
1314
1315         for (i = 0; i < nr_irqs; i++) {
1316                 err = its_alloc_device_irq(its_dev, &hwirq);
1317                 if (err)
1318                         return err;
1319
1320                 err = its_irq_gic_domain_alloc(domain, virq + i, hwirq);
1321                 if (err)
1322                         return err;
1323
1324                 irq_domain_set_hwirq_and_chip(domain, virq + i,
1325                                               hwirq, &its_irq_chip, its_dev);
1326                 dev_dbg(info->scratchpad[1].ptr, "ID:%d pID:%d vID:%d\n",
1327                         (int)(hwirq - its_dev->event_map.lpi_base),
1328                         (int)hwirq, virq + i);
1329         }
1330
1331         return 0;
1332 }
1333
1334 static void its_irq_domain_activate(struct irq_domain *domain,
1335                                     struct irq_data *d)
1336 {
1337         struct its_device *its_dev = irq_data_get_irq_chip_data(d);
1338         u32 event = its_get_event_id(d);
1339
1340         /* Bind the LPI to the first possible CPU */
1341         its_dev->event_map.col_map[event] = cpumask_first(cpu_online_mask);
1342
1343         /* Map the GIC IRQ and event to the device */
1344         its_send_mapvi(its_dev, d->hwirq, event);
1345 }
1346
1347 static void its_irq_domain_deactivate(struct irq_domain *domain,
1348                                       struct irq_data *d)
1349 {
1350         struct its_device *its_dev = irq_data_get_irq_chip_data(d);
1351         u32 event = its_get_event_id(d);
1352
1353         /* Stop the delivery of interrupts */
1354         its_send_discard(its_dev, event);
1355 }
1356
1357 static void its_irq_domain_free(struct irq_domain *domain, unsigned int virq,
1358                                 unsigned int nr_irqs)
1359 {
1360         struct irq_data *d = irq_domain_get_irq_data(domain, virq);
1361         struct its_device *its_dev = irq_data_get_irq_chip_data(d);
1362         int i;
1363
1364         for (i = 0; i < nr_irqs; i++) {
1365                 struct irq_data *data = irq_domain_get_irq_data(domain,
1366                                                                 virq + i);
1367                 u32 event = its_get_event_id(data);
1368
1369                 /* Mark interrupt index as unused */
1370                 clear_bit(event, its_dev->event_map.lpi_map);
1371
1372                 /* Nuke the entry in the domain */
1373                 irq_domain_reset_irq_data(data);
1374         }
1375
1376         /* If all interrupts have been freed, start mopping the floor */
1377         if (bitmap_empty(its_dev->event_map.lpi_map,
1378                          its_dev->event_map.nr_lpis)) {
1379                 its_lpi_free(&its_dev->event_map);
1380
1381                 /* Unmap device/itt */
1382                 its_send_mapd(its_dev, 0);
1383                 its_free_device(its_dev);
1384         }
1385
1386         irq_domain_free_irqs_parent(domain, virq, nr_irqs);
1387 }
1388
1389 static const struct irq_domain_ops its_domain_ops = {
1390         .alloc                  = its_irq_domain_alloc,
1391         .free                   = its_irq_domain_free,
1392         .activate               = its_irq_domain_activate,
1393         .deactivate             = its_irq_domain_deactivate,
1394 };
1395
1396 static int its_force_quiescent(void __iomem *base)
1397 {
1398         u32 count = 1000000;    /* 1s */
1399         u32 val;
1400
1401         val = readl_relaxed(base + GITS_CTLR);
1402         if (val & GITS_CTLR_QUIESCENT)
1403                 return 0;
1404
1405         /* Disable the generation of all interrupts to this ITS */
1406         val &= ~GITS_CTLR_ENABLE;
1407         writel_relaxed(val, base + GITS_CTLR);
1408
1409         /* Poll GITS_CTLR and wait until ITS becomes quiescent */
1410         while (1) {
1411                 val = readl_relaxed(base + GITS_CTLR);
1412                 if (val & GITS_CTLR_QUIESCENT)
1413                         return 0;
1414
1415                 count--;
1416                 if (!count)
1417                         return -EBUSY;
1418
1419                 cpu_relax();
1420                 udelay(1);
1421         }
1422 }
1423
1424 static int its_probe(struct device_node *node, struct irq_domain *parent)
1425 {
1426         struct resource res;
1427         struct its_node *its;
1428         void __iomem *its_base;
1429         u32 val;
1430         u64 baser, tmp;
1431         int err;
1432
1433         err = of_address_to_resource(node, 0, &res);
1434         if (err) {
1435                 pr_warn("%s: no regs?\n", node->full_name);
1436                 return -ENXIO;
1437         }
1438
1439         its_base = ioremap(res.start, resource_size(&res));
1440         if (!its_base) {
1441                 pr_warn("%s: unable to map registers\n", node->full_name);
1442                 return -ENOMEM;
1443         }
1444
1445         val = readl_relaxed(its_base + GITS_PIDR2) & GIC_PIDR2_ARCH_MASK;
1446         if (val != 0x30 && val != 0x40) {
1447                 pr_warn("%s: no ITS detected, giving up\n", node->full_name);
1448                 err = -ENODEV;
1449                 goto out_unmap;
1450         }
1451
1452         err = its_force_quiescent(its_base);
1453         if (err) {
1454                 pr_warn("%s: failed to quiesce, giving up\n",
1455                         node->full_name);
1456                 goto out_unmap;
1457         }
1458
1459         pr_info("ITS: %s\n", node->full_name);
1460
1461         its = kzalloc(sizeof(*its), GFP_KERNEL);
1462         if (!its) {
1463                 err = -ENOMEM;
1464                 goto out_unmap;
1465         }
1466
1467         raw_spin_lock_init(&its->lock);
1468         INIT_LIST_HEAD(&its->entry);
1469         INIT_LIST_HEAD(&its->its_device_list);
1470         its->base = its_base;
1471         its->phys_base = res.start;
1472         its->msi_chip.of_node = node;
1473         its->ite_size = ((readl_relaxed(its_base + GITS_TYPER) >> 4) & 0xf) + 1;
1474
1475         its->cmd_base = kzalloc(ITS_CMD_QUEUE_SZ, GFP_KERNEL);
1476         if (!its->cmd_base) {
1477                 err = -ENOMEM;
1478                 goto out_free_its;
1479         }
1480         its->cmd_write = its->cmd_base;
1481
1482         err = its_alloc_tables(its);
1483         if (err)
1484                 goto out_free_cmd;
1485
1486         err = its_alloc_collections(its);
1487         if (err)
1488                 goto out_free_tables;
1489
1490         baser = (virt_to_phys(its->cmd_base)    |
1491                  GITS_CBASER_WaWb               |
1492                  GITS_CBASER_InnerShareable     |
1493                  (ITS_CMD_QUEUE_SZ / SZ_4K - 1) |
1494                  GITS_CBASER_VALID);
1495
1496         writeq_relaxed(baser, its->base + GITS_CBASER);
1497         tmp = readq_relaxed(its->base + GITS_CBASER);
1498
1499         if ((tmp ^ baser) & GITS_CBASER_SHAREABILITY_MASK) {
1500                 if (!(tmp & GITS_CBASER_SHAREABILITY_MASK)) {
1501                         /*
1502                          * The HW reports non-shareable, we must
1503                          * remove the cacheability attributes as
1504                          * well.
1505                          */
1506                         baser &= ~(GITS_CBASER_SHAREABILITY_MASK |
1507                                    GITS_CBASER_CACHEABILITY_MASK);
1508                         baser |= GITS_CBASER_nC;
1509                         writeq_relaxed(baser, its->base + GITS_CBASER);
1510                 }
1511                 pr_info("ITS: using cache flushing for cmd queue\n");
1512                 its->flags |= ITS_FLAGS_CMDQ_NEEDS_FLUSHING;
1513         }
1514
1515         writeq_relaxed(0, its->base + GITS_CWRITER);
1516         writel_relaxed(GITS_CTLR_ENABLE, its->base + GITS_CTLR);
1517
1518         if (of_property_read_bool(its->msi_chip.of_node, "msi-controller")) {
1519                 its->domain = irq_domain_add_tree(NULL, &its_domain_ops, its);
1520                 if (!its->domain) {
1521                         err = -ENOMEM;
1522                         goto out_free_tables;
1523                 }
1524
1525                 its->domain->parent = parent;
1526
1527                 its->msi_chip.domain = pci_msi_create_irq_domain(node,
1528                                                                  &its_pci_msi_domain_info,
1529                                                                  its->domain);
1530                 if (!its->msi_chip.domain) {
1531                         err = -ENOMEM;
1532                         goto out_free_domains;
1533                 }
1534
1535                 err = of_pci_msi_chip_add(&its->msi_chip);
1536                 if (err)
1537                         goto out_free_domains;
1538         }
1539
1540         spin_lock(&its_lock);
1541         list_add(&its->entry, &its_nodes);
1542         spin_unlock(&its_lock);
1543
1544         return 0;
1545
1546 out_free_domains:
1547         if (its->msi_chip.domain)
1548                 irq_domain_remove(its->msi_chip.domain);
1549         if (its->domain)
1550                 irq_domain_remove(its->domain);
1551 out_free_tables:
1552         its_free_tables(its);
1553 out_free_cmd:
1554         kfree(its->cmd_base);
1555 out_free_its:
1556         kfree(its);
1557 out_unmap:
1558         iounmap(its_base);
1559         pr_err("ITS: failed probing %s (%d)\n", node->full_name, err);
1560         return err;
1561 }
1562
1563 static bool gic_rdists_supports_plpis(void)
1564 {
1565         return !!(readl_relaxed(gic_data_rdist_rd_base() + GICR_TYPER) & GICR_TYPER_PLPIS);
1566 }
1567
1568 int its_cpu_init(void)
1569 {
1570         if (!list_empty(&its_nodes)) {
1571                 if (!gic_rdists_supports_plpis()) {
1572                         pr_info("CPU%d: LPIs not supported\n", smp_processor_id());
1573                         return -ENXIO;
1574                 }
1575                 its_cpu_init_lpis();
1576                 its_cpu_init_collection();
1577         }
1578
1579         return 0;
1580 }
1581
1582 static struct of_device_id its_device_id[] = {
1583         {       .compatible     = "arm,gic-v3-its",     },
1584         {},
1585 };
1586
1587 int its_init(struct device_node *node, struct rdists *rdists,
1588              struct irq_domain *parent_domain)
1589 {
1590         struct device_node *np;
1591
1592         for (np = of_find_matching_node(node, its_device_id); np;
1593              np = of_find_matching_node(np, its_device_id)) {
1594                 its_probe(np, parent_domain);
1595         }
1596
1597         if (list_empty(&its_nodes)) {
1598                 pr_warn("ITS: No ITS available, not enabling LPIs\n");
1599                 return -ENXIO;
1600         }
1601
1602         gic_rdists = rdists;
1603         gic_root_node = node;
1604
1605         its_alloc_lpi_tables();
1606         its_lpi_init(rdists->id_bits);
1607
1608         return 0;
1609 }