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