1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef LINUX_MSI_H 3 #define LINUX_MSI_H 4 5 /* 6 * This header file contains MSI data structures and functions which are 7 * only relevant for: 8 * - Interrupt core code 9 * - PCI/MSI core code 10 * - MSI interrupt domain implementations 11 * - IOMMU, low level VFIO, NTB and other justified exceptions 12 * dealing with low level MSI details. 13 * 14 * Regular device drivers have no business with any of these functions and 15 * especially storing MSI descriptor pointers in random code is considered 16 * abuse. The only function which is relevant for drivers is msi_get_virq(). 17 */ 18 19 #include <linux/cpumask.h> 20 #include <linux/xarray.h> 21 #include <linux/mutex.h> 22 #include <linux/list.h> 23 #include <asm/msi.h> 24 25 /* Dummy shadow structures if an architecture does not define them */ 26 #ifndef arch_msi_msg_addr_lo 27 typedef struct arch_msi_msg_addr_lo { 28 u32 address_lo; 29 } __attribute__ ((packed)) arch_msi_msg_addr_lo_t; 30 #endif 31 32 #ifndef arch_msi_msg_addr_hi 33 typedef struct arch_msi_msg_addr_hi { 34 u32 address_hi; 35 } __attribute__ ((packed)) arch_msi_msg_addr_hi_t; 36 #endif 37 38 #ifndef arch_msi_msg_data 39 typedef struct arch_msi_msg_data { 40 u32 data; 41 } __attribute__ ((packed)) arch_msi_msg_data_t; 42 #endif 43 44 /** 45 * msi_msg - Representation of a MSI message 46 * @address_lo: Low 32 bits of msi message address 47 * @arch_addrlo: Architecture specific shadow of @address_lo 48 * @address_hi: High 32 bits of msi message address 49 * (only used when device supports it) 50 * @arch_addrhi: Architecture specific shadow of @address_hi 51 * @data: MSI message data (usually 16 bits) 52 * @arch_data: Architecture specific shadow of @data 53 */ 54 struct msi_msg { 55 union { 56 u32 address_lo; 57 arch_msi_msg_addr_lo_t arch_addr_lo; 58 }; 59 union { 60 u32 address_hi; 61 arch_msi_msg_addr_hi_t arch_addr_hi; 62 }; 63 union { 64 u32 data; 65 arch_msi_msg_data_t arch_data; 66 }; 67 }; 68 69 extern int pci_msi_ignore_mask; 70 /* Helper functions */ 71 struct irq_data; 72 struct msi_desc; 73 struct pci_dev; 74 struct platform_msi_priv_data; 75 struct device_attribute; 76 77 void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg); 78 #ifdef CONFIG_GENERIC_MSI_IRQ 79 void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg); 80 #else 81 static inline void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg) 82 { 83 } 84 #endif 85 86 typedef void (*irq_write_msi_msg_t)(struct msi_desc *desc, 87 struct msi_msg *msg); 88 89 /** 90 * pci_msi_desc - PCI/MSI specific MSI descriptor data 91 * 92 * @msi_mask: [PCI MSI] MSI cached mask bits 93 * @msix_ctrl: [PCI MSI-X] MSI-X cached per vector control bits 94 * @is_msix: [PCI MSI/X] True if MSI-X 95 * @multiple: [PCI MSI/X] log2 num of messages allocated 96 * @multi_cap: [PCI MSI/X] log2 num of messages supported 97 * @can_mask: [PCI MSI/X] Masking supported? 98 * @is_64: [PCI MSI/X] Address size: 0=32bit 1=64bit 99 * @default_irq:[PCI MSI/X] The default pre-assigned non-MSI irq 100 * @mask_pos: [PCI MSI] Mask register position 101 * @mask_base: [PCI MSI-X] Mask register base address 102 */ 103 struct pci_msi_desc { 104 union { 105 u32 msi_mask; 106 u32 msix_ctrl; 107 }; 108 struct { 109 u8 is_msix : 1; 110 u8 multiple : 3; 111 u8 multi_cap : 3; 112 u8 can_mask : 1; 113 u8 is_64 : 1; 114 u8 is_virtual : 1; 115 unsigned default_irq; 116 } msi_attrib; 117 union { 118 u8 mask_pos; 119 void __iomem *mask_base; 120 }; 121 }; 122 123 #define MSI_MAX_INDEX ((unsigned int)USHRT_MAX) 124 125 /** 126 * struct msi_desc - Descriptor structure for MSI based interrupts 127 * @irq: The base interrupt number 128 * @nvec_used: The number of vectors used 129 * @dev: Pointer to the device which uses this descriptor 130 * @msg: The last set MSI message cached for reuse 131 * @affinity: Optional pointer to a cpu affinity mask for this descriptor 132 * @sysfs_attr: Pointer to sysfs device attribute 133 * 134 * @write_msi_msg: Callback that may be called when the MSI message 135 * address or data changes 136 * @write_msi_msg_data: Data parameter for the callback. 137 * 138 * @msi_index: Index of the msi descriptor 139 * @pci: PCI specific msi descriptor data 140 */ 141 struct msi_desc { 142 /* Shared device/bus type independent data */ 143 unsigned int irq; 144 unsigned int nvec_used; 145 struct device *dev; 146 struct msi_msg msg; 147 struct irq_affinity_desc *affinity; 148 #ifdef CONFIG_IRQ_MSI_IOMMU 149 const void *iommu_cookie; 150 #endif 151 #ifdef CONFIG_SYSFS 152 struct device_attribute *sysfs_attrs; 153 #endif 154 155 void (*write_msi_msg)(struct msi_desc *entry, void *data); 156 void *write_msi_msg_data; 157 158 u16 msi_index; 159 struct pci_msi_desc pci; 160 }; 161 162 /* 163 * Filter values for the MSI descriptor iterators and accessor functions. 164 */ 165 enum msi_desc_filter { 166 /* All descriptors */ 167 MSI_DESC_ALL, 168 /* Descriptors which have no interrupt associated */ 169 MSI_DESC_NOTASSOCIATED, 170 /* Descriptors which have an interrupt associated */ 171 MSI_DESC_ASSOCIATED, 172 }; 173 174 /** 175 * msi_device_data - MSI per device data 176 * @properties: MSI properties which are interesting to drivers 177 * @platform_data: Platform-MSI specific data 178 * @mutex: Mutex protecting the MSI descriptor store 179 * @__store: Xarray for storing MSI descriptor pointers 180 * @__iter_idx: Index to search the next entry for iterators 181 */ 182 struct msi_device_data { 183 unsigned long properties; 184 struct platform_msi_priv_data *platform_data; 185 struct mutex mutex; 186 struct xarray __store; 187 unsigned long __iter_idx; 188 }; 189 190 int msi_setup_device_data(struct device *dev); 191 192 unsigned int msi_get_virq(struct device *dev, unsigned int index); 193 void msi_lock_descs(struct device *dev); 194 void msi_unlock_descs(struct device *dev); 195 196 struct msi_desc *msi_first_desc(struct device *dev, enum msi_desc_filter filter); 197 struct msi_desc *msi_next_desc(struct device *dev, enum msi_desc_filter filter); 198 199 /** 200 * msi_for_each_desc - Iterate the MSI descriptors 201 * 202 * @desc: struct msi_desc pointer used as iterator 203 * @dev: struct device pointer - device to iterate 204 * @filter: Filter for descriptor selection 205 * 206 * Notes: 207 * - The loop must be protected with a msi_lock_descs()/msi_unlock_descs() 208 * pair. 209 * - It is safe to remove a retrieved MSI descriptor in the loop. 210 */ 211 #define msi_for_each_desc(desc, dev, filter) \ 212 for ((desc) = msi_first_desc((dev), (filter)); (desc); \ 213 (desc) = msi_next_desc((dev), (filter))) 214 215 #define msi_desc_to_dev(desc) ((desc)->dev) 216 217 #ifdef CONFIG_IRQ_MSI_IOMMU 218 static inline const void *msi_desc_get_iommu_cookie(struct msi_desc *desc) 219 { 220 return desc->iommu_cookie; 221 } 222 223 static inline void msi_desc_set_iommu_cookie(struct msi_desc *desc, 224 const void *iommu_cookie) 225 { 226 desc->iommu_cookie = iommu_cookie; 227 } 228 #else 229 static inline const void *msi_desc_get_iommu_cookie(struct msi_desc *desc) 230 { 231 return NULL; 232 } 233 234 static inline void msi_desc_set_iommu_cookie(struct msi_desc *desc, 235 const void *iommu_cookie) 236 { 237 } 238 #endif 239 240 #ifdef CONFIG_PCI_MSI 241 struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc); 242 void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg); 243 #else /* CONFIG_PCI_MSI */ 244 static inline void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg) 245 { 246 } 247 #endif /* CONFIG_PCI_MSI */ 248 249 int msi_add_msi_desc(struct device *dev, struct msi_desc *init_desc); 250 void msi_free_msi_descs_range(struct device *dev, enum msi_desc_filter filter, 251 unsigned int first_index, unsigned int last_index); 252 253 /** 254 * msi_free_msi_descs - Free MSI descriptors of a device 255 * @dev: Device to free the descriptors 256 */ 257 static inline void msi_free_msi_descs(struct device *dev) 258 { 259 msi_free_msi_descs_range(dev, MSI_DESC_ALL, 0, MSI_MAX_INDEX); 260 } 261 262 void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg); 263 void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg); 264 265 void pci_msi_mask_irq(struct irq_data *data); 266 void pci_msi_unmask_irq(struct irq_data *data); 267 268 /* 269 * The arch hooks to setup up msi irqs. Default functions are implemented 270 * as weak symbols so that they /can/ be overriden by architecture specific 271 * code if needed. These hooks can only be enabled by the architecture. 272 * 273 * If CONFIG_PCI_MSI_ARCH_FALLBACKS is not selected they are replaced by 274 * stubs with warnings. 275 */ 276 #ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS 277 int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc); 278 void arch_teardown_msi_irq(unsigned int irq); 279 int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type); 280 void arch_teardown_msi_irqs(struct pci_dev *dev); 281 #ifdef CONFIG_SYSFS 282 int msi_device_populate_sysfs(struct device *dev); 283 void msi_device_destroy_sysfs(struct device *dev); 284 #else /* CONFIG_SYSFS */ 285 static inline int msi_device_populate_sysfs(struct device *dev) { return 0; } 286 static inline void msi_device_destroy_sysfs(struct device *dev) { } 287 #endif /* !CONFIG_SYSFS */ 288 #endif /* CONFIG_PCI_MSI_ARCH_FALLBACKS */ 289 290 /* 291 * The restore hook is still available even for fully irq domain based 292 * setups. Courtesy to XEN/X86. 293 */ 294 bool arch_restore_msi_irqs(struct pci_dev *dev); 295 296 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN 297 298 #include <linux/irqhandler.h> 299 300 struct irq_domain; 301 struct irq_domain_ops; 302 struct irq_chip; 303 struct device_node; 304 struct fwnode_handle; 305 struct msi_domain_info; 306 307 /** 308 * struct msi_domain_ops - MSI interrupt domain callbacks 309 * @get_hwirq: Retrieve the resulting hw irq number 310 * @msi_init: Domain specific init function for MSI interrupts 311 * @msi_free: Domain specific function to free a MSI interrupts 312 * @msi_check: Callback for verification of the domain/info/dev data 313 * @msi_prepare: Prepare the allocation of the interrupts in the domain 314 * @set_desc: Set the msi descriptor for an interrupt 315 * @domain_alloc_irqs: Optional function to override the default allocation 316 * function. 317 * @domain_free_irqs: Optional function to override the default free 318 * function. 319 * 320 * @get_hwirq, @msi_init and @msi_free are callbacks used by the underlying 321 * irqdomain. 322 * 323 * @msi_check, @msi_prepare and @set_desc are callbacks used by 324 * msi_domain_alloc/free_irqs(). 325 * 326 * @domain_alloc_irqs, @domain_free_irqs can be used to override the 327 * default allocation/free functions (__msi_domain_alloc/free_irqs). This 328 * is initially for a wrapper around XENs seperate MSI universe which can't 329 * be wrapped into the regular irq domains concepts by mere mortals. This 330 * allows to universally use msi_domain_alloc/free_irqs without having to 331 * special case XEN all over the place. 332 * 333 * Contrary to other operations @domain_alloc_irqs and @domain_free_irqs 334 * are set to the default implementation if NULL and even when 335 * MSI_FLAG_USE_DEF_DOM_OPS is not set to avoid breaking existing users and 336 * because these callbacks are obviously mandatory. 337 * 338 * This is NOT meant to be abused, but it can be useful to build wrappers 339 * for specialized MSI irq domains which need extra work before and after 340 * calling __msi_domain_alloc_irqs()/__msi_domain_free_irqs(). 341 */ 342 struct msi_domain_ops { 343 irq_hw_number_t (*get_hwirq)(struct msi_domain_info *info, 344 msi_alloc_info_t *arg); 345 int (*msi_init)(struct irq_domain *domain, 346 struct msi_domain_info *info, 347 unsigned int virq, irq_hw_number_t hwirq, 348 msi_alloc_info_t *arg); 349 void (*msi_free)(struct irq_domain *domain, 350 struct msi_domain_info *info, 351 unsigned int virq); 352 int (*msi_check)(struct irq_domain *domain, 353 struct msi_domain_info *info, 354 struct device *dev); 355 int (*msi_prepare)(struct irq_domain *domain, 356 struct device *dev, int nvec, 357 msi_alloc_info_t *arg); 358 void (*set_desc)(msi_alloc_info_t *arg, 359 struct msi_desc *desc); 360 int (*domain_alloc_irqs)(struct irq_domain *domain, 361 struct device *dev, int nvec); 362 void (*domain_free_irqs)(struct irq_domain *domain, 363 struct device *dev); 364 }; 365 366 /** 367 * struct msi_domain_info - MSI interrupt domain data 368 * @flags: Flags to decribe features and capabilities 369 * @ops: The callback data structure 370 * @chip: Optional: associated interrupt chip 371 * @chip_data: Optional: associated interrupt chip data 372 * @handler: Optional: associated interrupt flow handler 373 * @handler_data: Optional: associated interrupt flow handler data 374 * @handler_name: Optional: associated interrupt flow handler name 375 * @data: Optional: domain specific data 376 */ 377 struct msi_domain_info { 378 u32 flags; 379 struct msi_domain_ops *ops; 380 struct irq_chip *chip; 381 void *chip_data; 382 irq_flow_handler_t handler; 383 void *handler_data; 384 const char *handler_name; 385 void *data; 386 }; 387 388 /* Flags for msi_domain_info */ 389 enum { 390 /* 391 * Init non implemented ops callbacks with default MSI domain 392 * callbacks. 393 */ 394 MSI_FLAG_USE_DEF_DOM_OPS = (1 << 0), 395 /* 396 * Init non implemented chip callbacks with default MSI chip 397 * callbacks. 398 */ 399 MSI_FLAG_USE_DEF_CHIP_OPS = (1 << 1), 400 /* Support multiple PCI MSI interrupts */ 401 MSI_FLAG_MULTI_PCI_MSI = (1 << 2), 402 /* Support PCI MSIX interrupts */ 403 MSI_FLAG_PCI_MSIX = (1 << 3), 404 /* Needs early activate, required for PCI */ 405 MSI_FLAG_ACTIVATE_EARLY = (1 << 4), 406 /* 407 * Must reactivate when irq is started even when 408 * MSI_FLAG_ACTIVATE_EARLY has been set. 409 */ 410 MSI_FLAG_MUST_REACTIVATE = (1 << 5), 411 /* Is level-triggered capable, using two messages */ 412 MSI_FLAG_LEVEL_CAPABLE = (1 << 6), 413 /* Populate sysfs on alloc() and destroy it on free() */ 414 MSI_FLAG_DEV_SYSFS = (1 << 7), 415 /* MSI-X entries must be contiguous */ 416 MSI_FLAG_MSIX_CONTIGUOUS = (1 << 8), 417 /* Allocate simple MSI descriptors */ 418 MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS = (1 << 9), 419 /* Free MSI descriptors */ 420 MSI_FLAG_FREE_MSI_DESCS = (1 << 10), 421 }; 422 423 int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask, 424 bool force); 425 426 struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode, 427 struct msi_domain_info *info, 428 struct irq_domain *parent); 429 int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, 430 int nvec); 431 int msi_domain_alloc_irqs_descs_locked(struct irq_domain *domain, struct device *dev, 432 int nvec); 433 int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, 434 int nvec); 435 void __msi_domain_free_irqs(struct irq_domain *domain, struct device *dev); 436 void msi_domain_free_irqs_descs_locked(struct irq_domain *domain, struct device *dev); 437 void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev); 438 struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain); 439 440 struct irq_domain *platform_msi_create_irq_domain(struct fwnode_handle *fwnode, 441 struct msi_domain_info *info, 442 struct irq_domain *parent); 443 int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec, 444 irq_write_msi_msg_t write_msi_msg); 445 void platform_msi_domain_free_irqs(struct device *dev); 446 447 /* When an MSI domain is used as an intermediate domain */ 448 int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev, 449 int nvec, msi_alloc_info_t *args); 450 int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev, 451 int virq, int nvec, msi_alloc_info_t *args); 452 struct irq_domain * 453 __platform_msi_create_device_domain(struct device *dev, 454 unsigned int nvec, 455 bool is_tree, 456 irq_write_msi_msg_t write_msi_msg, 457 const struct irq_domain_ops *ops, 458 void *host_data); 459 460 #define platform_msi_create_device_domain(dev, nvec, write, ops, data) \ 461 __platform_msi_create_device_domain(dev, nvec, false, write, ops, data) 462 #define platform_msi_create_device_tree_domain(dev, nvec, write, ops, data) \ 463 __platform_msi_create_device_domain(dev, nvec, true, write, ops, data) 464 465 int platform_msi_device_domain_alloc(struct irq_domain *domain, unsigned int virq, 466 unsigned int nr_irqs); 467 void platform_msi_device_domain_free(struct irq_domain *domain, unsigned int virq, 468 unsigned int nvec); 469 void *platform_msi_get_host_data(struct irq_domain *domain); 470 #endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */ 471 472 #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN 473 struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode, 474 struct msi_domain_info *info, 475 struct irq_domain *parent); 476 u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev); 477 struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev); 478 bool pci_dev_has_special_msi_domain(struct pci_dev *pdev); 479 #else 480 static inline struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) 481 { 482 return NULL; 483 } 484 #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ 485 486 #endif /* LINUX_MSI_H */ 487