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