xref: /linux/include/linux/msi.h (revision 3381d7b2b3dd012d366b9ba9339f98d54bea69fd)
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.
17  *
18  * Device driver relevant functions are available in <linux/msi_api.h>
19  */
20 
21 #include <linux/irqdomain_defs.h>
22 #include <linux/cpumask_types.h>
23 #include <linux/msi_api.h>
24 #include <linux/irq.h>
25 
26 #include <asm/msi.h>
27 
28 /* Dummy shadow structures if an architecture does not define them */
29 #ifndef arch_msi_msg_addr_lo
30 typedef struct arch_msi_msg_addr_lo {
31 	u32	address_lo;
32 } __attribute__ ((packed)) arch_msi_msg_addr_lo_t;
33 #endif
34 
35 #ifndef arch_msi_msg_addr_hi
36 typedef struct arch_msi_msg_addr_hi {
37 	u32	address_hi;
38 } __attribute__ ((packed)) arch_msi_msg_addr_hi_t;
39 #endif
40 
41 #ifndef arch_msi_msg_data
42 typedef struct arch_msi_msg_data {
43 	u32	data;
44 } __attribute__ ((packed)) arch_msi_msg_data_t;
45 #endif
46 
47 #ifndef arch_is_isolated_msi
48 #define arch_is_isolated_msi() false
49 #endif
50 
51 /**
52  * struct msi_msg - Representation of a MSI message
53  * @address_lo:		Low 32 bits of msi message address
54  * @arch_addr_lo:	Architecture specific shadow of @address_lo
55  * @address_hi:		High 32 bits of msi message address
56  *			(only used when device supports it)
57  * @arch_addr_hi:	Architecture specific shadow of @address_hi
58  * @data:		MSI message data (usually 16 bits)
59  * @arch_data:		Architecture specific shadow of @data
60  */
61 struct msi_msg {
62 	union {
63 		u32			address_lo;
64 		arch_msi_msg_addr_lo_t	arch_addr_lo;
65 	};
66 	union {
67 		u32			address_hi;
68 		arch_msi_msg_addr_hi_t	arch_addr_hi;
69 	};
70 	union {
71 		u32			data;
72 		arch_msi_msg_data_t	arch_data;
73 	};
74 };
75 
76 /* Helper functions */
77 struct msi_desc;
78 struct pci_dev;
79 struct device_attribute;
80 struct irq_domain;
81 struct irq_affinity_desc;
82 
83 void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
84 #ifdef CONFIG_GENERIC_MSI_IRQ
85 void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg);
86 #else
get_cached_msi_msg(unsigned int irq,struct msi_msg * msg)87 static inline void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg) { }
88 #endif
89 
90 typedef void (*irq_write_msi_msg_t)(struct msi_desc *desc,
91 				    struct msi_msg *msg);
92 
93 /**
94  * struct pci_msi_desc - PCI/MSI specific MSI descriptor data
95  *
96  * @msi_mask:	[PCI MSI]   MSI cached mask bits
97  * @msix_ctrl:	[PCI MSI-X] MSI-X cached per vector control bits
98  * @is_msix:	[PCI MSI/X] True if MSI-X
99  * @multiple:	[PCI MSI/X] log2 num of messages allocated
100  * @multi_cap:	[PCI MSI/X] log2 num of messages supported
101  * @can_mask:	[PCI MSI/X] Masking supported?
102  * @is_64:	[PCI MSI/X] Address size: 0=32bit 1=64bit
103  * @default_irq:[PCI MSI/X] The default pre-assigned non-MSI irq
104  * @msi_attrib:	[PCI MSI/X] Compound struct of MSI/X attributes
105  * @mask_pos:	[PCI MSI]   Mask register position
106  * @mask_base:	[PCI MSI-X] Mask register base address
107  */
108 struct pci_msi_desc {
109 	union {
110 		u32 msi_mask;
111 		u32 msix_ctrl;
112 	};
113 	struct {
114 		u8	is_msix		: 1;
115 		u8	multiple	: 3;
116 		u8	multi_cap	: 3;
117 		u8	can_mask	: 1;
118 		u8	is_64		: 1;
119 		u8	is_virtual	: 1;
120 		unsigned default_irq;
121 	} msi_attrib;
122 	union {
123 		u8	mask_pos;
124 		void __iomem *mask_base;
125 	};
126 };
127 
128 /**
129  * union msi_domain_cookie - Opaque MSI domain specific data
130  * @value:	u64 value store
131  * @ptr:	Pointer to domain specific data
132  * @iobase:	Domain specific IOmem pointer
133  *
134  * The content of this data is implementation defined and used by the MSI
135  * domain to store domain specific information which is requried for
136  * interrupt chip callbacks.
137  */
138 union msi_domain_cookie {
139 	u64	value;
140 	void	*ptr;
141 	void	__iomem *iobase;
142 };
143 
144 /**
145  * struct msi_desc_data - Generic MSI descriptor data
146  * @dcookie:	Cookie for MSI domain specific data which is required
147  *		for irq_chip callbacks
148  * @icookie:	Cookie for the MSI interrupt instance provided by
149  *		the usage site to the allocation function
150  *
151  * The content of this data is implementation defined, e.g. PCI/IMS
152  * implementations define the meaning of the data. The MSI core ignores
153  * this data completely.
154  */
155 struct msi_desc_data {
156 	union msi_domain_cookie		dcookie;
157 	union msi_instance_cookie	icookie;
158 };
159 
160 #define MSI_MAX_INDEX		((unsigned int)USHRT_MAX)
161 
162 /**
163  * struct msi_desc - Descriptor structure for MSI based interrupts
164  * @irq:	The base interrupt number
165  * @nvec_used:	The number of vectors used
166  * @dev:	Pointer to the device which uses this descriptor
167  * @msg:	The last set MSI message cached for reuse
168  * @affinity:	Optional pointer to a cpu affinity mask for this descriptor
169  * @iommu_msi_iova: Optional shifted IOVA from the IOMMU to override the msi_addr.
170  *                  Only used if iommu_msi_shift != 0
171  * @iommu_msi_shift: Indicates how many bits of the original address should be
172  *                   preserved when using iommu_msi_iova.
173  * @sysfs_attrs:	Pointer to sysfs device attribute
174  *
175  * @write_msi_msg:	Callback that may be called when the MSI message
176  *			address or data changes
177  * @write_msi_msg_data:	Data parameter for the callback.
178  *
179  * @msi_index:	Index of the msi descriptor
180  * @pci:	PCI specific msi descriptor data
181  * @data:	Generic MSI descriptor data
182  */
183 struct msi_desc {
184 	/* Shared device/bus type independent data */
185 	unsigned int			irq;
186 	unsigned int			nvec_used;
187 	struct device			*dev;
188 	struct msi_msg			msg;
189 	struct irq_affinity_desc	*affinity;
190 #ifdef CONFIG_IRQ_MSI_IOMMU
191 	u64				iommu_msi_iova : 58;
192 	u64				iommu_msi_shift : 6;
193 #endif
194 #ifdef CONFIG_SYSFS
195 	struct device_attribute		*sysfs_attrs;
196 #endif
197 
198 	void (*write_msi_msg)(struct msi_desc *entry, void *data);
199 	void *write_msi_msg_data;
200 
201 	u16				msi_index;
202 	union {
203 		struct pci_msi_desc	pci;
204 		struct msi_desc_data	data;
205 	};
206 };
207 
208 /*
209  * Filter values for the MSI descriptor iterators and accessor functions.
210  */
211 enum msi_desc_filter {
212 	/* All descriptors */
213 	MSI_DESC_ALL,
214 	/* Descriptors which have no interrupt associated */
215 	MSI_DESC_NOTASSOCIATED,
216 	/* Descriptors which have an interrupt associated */
217 	MSI_DESC_ASSOCIATED,
218 };
219 
220 
221 /**
222  * struct msi_dev_domain - The internals of MSI domain info per device
223  * @store:		Xarray for storing MSI descriptor pointers
224  * @domain:		Pointer to a per device interrupt domain
225  */
226 struct msi_dev_domain {
227 	struct xarray		store;
228 	struct irq_domain	*domain;
229 };
230 
231 int msi_setup_device_data(struct device *dev);
232 
233 void __msi_lock_descs(struct device *dev);
234 void __msi_unlock_descs(struct device *dev);
235 
236 DEFINE_LOCK_GUARD_1(msi_descs_lock, struct device, __msi_lock_descs(_T->lock),
237 		    __msi_unlock_descs(_T->lock));
238 
239 struct msi_desc *msi_domain_first_desc(struct device *dev, unsigned int domid,
240 				       enum msi_desc_filter filter);
241 
242 /**
243  * msi_first_desc - Get the first MSI descriptor of the default irqdomain
244  * @dev:	Device to operate on
245  * @filter:	Descriptor state filter
246  *
247  * Must be called with the MSI descriptor mutex held, i.e. msi_lock_descs()
248  * must be invoked before the call.
249  *
250  * Return: Pointer to the first MSI descriptor matching the search
251  *	   criteria, NULL if none found.
252  */
msi_first_desc(struct device * dev,enum msi_desc_filter filter)253 static inline struct msi_desc *msi_first_desc(struct device *dev,
254 					      enum msi_desc_filter filter)
255 {
256 	return msi_domain_first_desc(dev, MSI_DEFAULT_DOMAIN, filter);
257 }
258 
259 struct msi_desc *msi_next_desc(struct device *dev, unsigned int domid,
260 			       enum msi_desc_filter filter);
261 
262 /**
263  * msi_domain_for_each_desc - Iterate the MSI descriptors in a specific domain
264  *
265  * @desc:	struct msi_desc pointer used as iterator
266  * @dev:	struct device pointer - device to iterate
267  * @domid:	The id of the interrupt domain which should be walked.
268  * @filter:	Filter for descriptor selection
269  *
270  * Notes:
271  *  - The loop must be protected with a msi_lock_descs()/msi_unlock_descs()
272  *    pair.
273  *  - It is safe to remove a retrieved MSI descriptor in the loop.
274  */
275 #define msi_domain_for_each_desc(desc, dev, domid, filter)			\
276 	for ((desc) = msi_domain_first_desc((dev), (domid), (filter)); (desc);	\
277 	     (desc) = msi_next_desc((dev), (domid), (filter)))
278 
279 /**
280  * msi_for_each_desc - Iterate the MSI descriptors in the default irqdomain
281  *
282  * @desc:	struct msi_desc pointer used as iterator
283  * @dev:	struct device pointer - device to iterate
284  * @filter:	Filter for descriptor selection
285  *
286  * Notes:
287  *  - The loop must be protected with a msi_lock_descs()/msi_unlock_descs()
288  *    pair.
289  *  - It is safe to remove a retrieved MSI descriptor in the loop.
290  */
291 #define msi_for_each_desc(desc, dev, filter)					\
292 	msi_domain_for_each_desc((desc), (dev), MSI_DEFAULT_DOMAIN, (filter))
293 
294 #define msi_desc_to_dev(desc)		((desc)->dev)
295 
msi_desc_set_iommu_msi_iova(struct msi_desc * desc,u64 msi_iova,unsigned int msi_shift)296 static inline void msi_desc_set_iommu_msi_iova(struct msi_desc *desc, u64 msi_iova,
297 					       unsigned int msi_shift)
298 {
299 #ifdef CONFIG_IRQ_MSI_IOMMU
300 	desc->iommu_msi_iova = msi_iova >> msi_shift;
301 	desc->iommu_msi_shift = msi_shift;
302 #endif
303 }
304 
305 /**
306  * msi_msg_set_addr() - Set MSI address in an MSI message
307  *
308  * @desc:	MSI descriptor that may carry an IOVA base address for MSI via @iommu_msi_iova/shift
309  * @msg:	Target MSI message to set its address_hi and address_lo
310  * @msi_addr:	Physical address to set the MSI message
311  *
312  * Notes:
313  *  - Override @msi_addr using the IOVA base address in the @desc if @iommu_msi_shift is set
314  *  - Otherwise, simply set @msi_addr to @msg
315  */
msi_msg_set_addr(struct msi_desc * desc,struct msi_msg * msg,phys_addr_t msi_addr)316 static inline void msi_msg_set_addr(struct msi_desc *desc, struct msi_msg *msg,
317 				    phys_addr_t msi_addr)
318 {
319 #ifdef CONFIG_IRQ_MSI_IOMMU
320 	if (desc->iommu_msi_shift) {
321 		u64 msi_iova = desc->iommu_msi_iova << desc->iommu_msi_shift;
322 
323 		msg->address_hi = upper_32_bits(msi_iova);
324 		msg->address_lo = lower_32_bits(msi_iova) |
325 				  (msi_addr & ((1 << desc->iommu_msi_shift) - 1));
326 		return;
327 	}
328 #endif
329 	msg->address_hi = upper_32_bits(msi_addr);
330 	msg->address_lo = lower_32_bits(msi_addr);
331 }
332 
333 int msi_domain_insert_msi_desc(struct device *dev, unsigned int domid,
334 			       struct msi_desc *init_desc);
335 /**
336  * msi_insert_msi_desc - Allocate and initialize a MSI descriptor in the
337  *			 default irqdomain and insert it at @init_desc->msi_index
338  * @dev:	Pointer to the device for which the descriptor is allocated
339  * @init_desc:	Pointer to an MSI descriptor to initialize the new descriptor
340  *
341  * Return: 0 on success or an appropriate failure code.
342  */
msi_insert_msi_desc(struct device * dev,struct msi_desc * init_desc)343 static inline int msi_insert_msi_desc(struct device *dev, struct msi_desc *init_desc)
344 {
345 	return msi_domain_insert_msi_desc(dev, MSI_DEFAULT_DOMAIN, init_desc);
346 }
347 
348 void msi_domain_free_msi_descs_range(struct device *dev, unsigned int domid,
349 				     unsigned int first, unsigned int last);
350 
351 /**
352  * msi_free_msi_descs_range - Free a range of MSI descriptors of a device
353  *			      in the default irqdomain
354  *
355  * @dev:	Device for which to free the descriptors
356  * @first:	Index to start freeing from (inclusive)
357  * @last:	Last index to be freed (inclusive)
358  */
msi_free_msi_descs_range(struct device * dev,unsigned int first,unsigned int last)359 static inline void msi_free_msi_descs_range(struct device *dev, unsigned int first,
360 					    unsigned int last)
361 {
362 	msi_domain_free_msi_descs_range(dev, MSI_DEFAULT_DOMAIN, first, last);
363 }
364 
365 /**
366  * msi_free_msi_descs - Free all MSI descriptors of a device in the default irqdomain
367  * @dev:	Device to free the descriptors
368  */
msi_free_msi_descs(struct device * dev)369 static inline void msi_free_msi_descs(struct device *dev)
370 {
371 	msi_free_msi_descs_range(dev, 0, MSI_MAX_INDEX);
372 }
373 
374 /*
375  * The arch hooks to setup up msi irqs. Default functions are implemented
376  * as weak symbols so that they /can/ be overriden by architecture specific
377  * code if needed. These hooks can only be enabled by the architecture.
378  *
379  * If CONFIG_PCI_MSI_ARCH_FALLBACKS is not selected they are replaced by
380  * stubs with warnings.
381  */
382 #ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS
383 int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc);
384 void arch_teardown_msi_irq(unsigned int irq);
385 int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type);
386 void arch_teardown_msi_irqs(struct pci_dev *dev);
387 #endif /* CONFIG_PCI_MSI_ARCH_FALLBACKS */
388 
389 /*
390  * Xen uses non-default msi_domain_ops and hence needs a way to populate sysfs
391  * entries of MSI IRQs.
392  */
393 #if defined(CONFIG_PCI_XEN) || defined(CONFIG_PCI_MSI_ARCH_FALLBACKS)
394 #ifdef CONFIG_SYSFS
395 int msi_device_populate_sysfs(struct device *dev);
396 void msi_device_destroy_sysfs(struct device *dev);
397 #else /* CONFIG_SYSFS */
msi_device_populate_sysfs(struct device * dev)398 static inline int msi_device_populate_sysfs(struct device *dev) { return 0; }
msi_device_destroy_sysfs(struct device * dev)399 static inline void msi_device_destroy_sysfs(struct device *dev) { }
400 #endif /* !CONFIG_SYSFS */
401 #endif /* CONFIG_PCI_XEN || CONFIG_PCI_MSI_ARCH_FALLBACKS */
402 
403 /*
404  * The restore hook is still available even for fully irq domain based
405  * setups. Courtesy to XEN/X86.
406  */
407 bool arch_restore_msi_irqs(struct pci_dev *dev);
408 
409 #ifdef CONFIG_GENERIC_MSI_IRQ
410 
411 #include <linux/irqhandler.h>
412 
413 struct irq_domain;
414 struct irq_domain_ops;
415 struct irq_chip;
416 struct irq_fwspec;
417 struct device_node;
418 struct fwnode_handle;
419 struct msi_domain_info;
420 
421 /**
422  * struct msi_domain_ops - MSI interrupt domain callbacks
423  * @get_hwirq:		Retrieve the resulting hw irq number
424  * @msi_init:		Domain specific init function for MSI interrupts
425  * @msi_free:		Domain specific function to free a MSI interrupts
426  * @msi_prepare:	Prepare the allocation of the interrupts in the domain
427  * @msi_teardown:	Reverse the effects of @msi_prepare
428  * @prepare_desc:	Optional function to prepare the allocated MSI descriptor
429  *			in the domain
430  * @set_desc:		Set the msi descriptor for an interrupt
431  * @domain_alloc_irqs:	Optional function to override the default allocation
432  *			function.
433  * @domain_free_irqs:	Optional function to override the default free
434  *			function.
435  * @msi_translate:	Optional translate callback to support the odd wire to
436  *			MSI bridges, e.g. MBIGEN
437  *
438  * @get_hwirq, @msi_init and @msi_free are callbacks used by the underlying
439  * irqdomain.
440  *
441  * @msi_check, @msi_prepare, @msi_teardown, @prepare_desc and
442  * @set_desc are callbacks used by the msi_domain_alloc/free_irqs*()
443  * variants.
444  *
445  * @domain_alloc_irqs, @domain_free_irqs can be used to override the
446  * default allocation/free functions (__msi_domain_alloc/free_irqs). This
447  * is initially for a wrapper around XENs seperate MSI universe which can't
448  * be wrapped into the regular irq domains concepts by mere mortals.  This
449  * allows to universally use msi_domain_alloc/free_irqs without having to
450  * special case XEN all over the place.
451  */
452 struct msi_domain_ops {
453 	irq_hw_number_t	(*get_hwirq)(struct msi_domain_info *info,
454 				     msi_alloc_info_t *arg);
455 	int		(*msi_init)(struct irq_domain *domain,
456 				    struct msi_domain_info *info,
457 				    unsigned int virq, irq_hw_number_t hwirq,
458 				    msi_alloc_info_t *arg);
459 	void		(*msi_free)(struct irq_domain *domain,
460 				    struct msi_domain_info *info,
461 				    unsigned int virq);
462 	int		(*msi_prepare)(struct irq_domain *domain,
463 				       struct device *dev, int nvec,
464 				       msi_alloc_info_t *arg);
465 	void		(*msi_teardown)(struct irq_domain *domain,
466 					msi_alloc_info_t *arg);
467 	void		(*prepare_desc)(struct irq_domain *domain, msi_alloc_info_t *arg,
468 					struct msi_desc *desc);
469 	void		(*set_desc)(msi_alloc_info_t *arg,
470 				    struct msi_desc *desc);
471 	int		(*domain_alloc_irqs)(struct irq_domain *domain,
472 					     struct device *dev, int nvec);
473 	void		(*domain_free_irqs)(struct irq_domain *domain,
474 					    struct device *dev);
475 	int		(*msi_translate)(struct irq_domain *domain, struct irq_fwspec *fwspec,
476 					 irq_hw_number_t *hwirq, unsigned int *type);
477 };
478 
479 /**
480  * struct msi_domain_info - MSI interrupt domain data
481  * @flags:		Flags to decribe features and capabilities
482  * @bus_token:		The domain bus token
483  * @hwsize:		The hardware table size or the software index limit.
484  *			If 0 then the size is considered unlimited and
485  *			gets initialized to the maximum software index limit
486  *			by the domain creation code.
487  * @ops:		The callback data structure
488  * @dev:		Device which creates the domain
489  * @chip:		Optional: associated interrupt chip
490  * @chip_data:		Optional: associated interrupt chip data
491  * @handler:		Optional: associated interrupt flow handler
492  * @handler_data:	Optional: associated interrupt flow handler data
493  * @handler_name:	Optional: associated interrupt flow handler name
494  * @alloc_data:		Optional: associated interrupt allocation data
495  * @data:		Optional: domain specific data
496  */
497 struct msi_domain_info {
498 	u32				flags;
499 	enum irq_domain_bus_token	bus_token;
500 	unsigned int			hwsize;
501 	struct msi_domain_ops		*ops;
502 	struct device			*dev;
503 	struct irq_chip			*chip;
504 	void				*chip_data;
505 	irq_flow_handler_t		handler;
506 	void				*handler_data;
507 	const char			*handler_name;
508 	msi_alloc_info_t		*alloc_data;
509 	void				*data;
510 };
511 
512 /**
513  * struct msi_domain_template - Template for MSI device domains
514  * @name:	Storage for the resulting name. Filled in by the core.
515  * @chip:	Interrupt chip for this domain
516  * @ops:	MSI domain ops
517  * @info:	MSI domain info data
518  * @alloc_info:	MSI domain allocation data (architecture specific)
519  */
520 struct msi_domain_template {
521 	char			name[48];
522 	struct irq_chip		chip;
523 	struct msi_domain_ops	ops;
524 	struct msi_domain_info	info;
525 	msi_alloc_info_t	alloc_info;
526 };
527 
528 /*
529  * Flags for msi_domain_info
530  *
531  * Bit 0-15:	Generic MSI functionality which is not subject to restriction
532  *		by parent domains
533  *
534  * Bit 16-31:	Functionality which depends on the underlying parent domain and
535  *		can be masked out by msi_parent_ops::init_dev_msi_info() when
536  *		a device MSI domain is initialized.
537  */
538 enum {
539 	/*
540 	 * Init non implemented ops callbacks with default MSI domain
541 	 * callbacks.
542 	 */
543 	MSI_FLAG_USE_DEF_DOM_OPS	= (1 << 0),
544 	/*
545 	 * Init non implemented chip callbacks with default MSI chip
546 	 * callbacks.
547 	 */
548 	MSI_FLAG_USE_DEF_CHIP_OPS	= (1 << 1),
549 	/* Needs early activate, required for PCI */
550 	MSI_FLAG_ACTIVATE_EARLY		= (1 << 2),
551 	/*
552 	 * Must reactivate when irq is started even when
553 	 * MSI_FLAG_ACTIVATE_EARLY has been set.
554 	 */
555 	MSI_FLAG_MUST_REACTIVATE	= (1 << 3),
556 	/* Populate sysfs on alloc() and destroy it on free() */
557 	MSI_FLAG_DEV_SYSFS		= (1 << 4),
558 	/* Allocate simple MSI descriptors */
559 	MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS	= (1 << 5),
560 	/* Free MSI descriptors */
561 	MSI_FLAG_FREE_MSI_DESCS		= (1 << 6),
562 	/* Use dev->fwnode for MSI device domain creation */
563 	MSI_FLAG_USE_DEV_FWNODE		= (1 << 7),
564 	/* Set parent->dev into domain->pm_dev on device domain creation */
565 	MSI_FLAG_PARENT_PM_DEV		= (1 << 8),
566 	/* Support for parent mask/unmask */
567 	MSI_FLAG_PCI_MSI_MASK_PARENT	= (1 << 9),
568 	/* Support for parent startup/shutdown */
569 	MSI_FLAG_PCI_MSI_STARTUP_PARENT	= (1 << 10),
570 
571 	/* Mask for the generic functionality */
572 	MSI_GENERIC_FLAGS_MASK		= GENMASK(15, 0),
573 
574 	/* Mask for the domain specific functionality */
575 	MSI_DOMAIN_FLAGS_MASK		= GENMASK(31, 16),
576 
577 	/* Support multiple PCI MSI interrupts */
578 	MSI_FLAG_MULTI_PCI_MSI		= (1 << 16),
579 	/* Support PCI MSIX interrupts */
580 	MSI_FLAG_PCI_MSIX		= (1 << 17),
581 	/* Is level-triggered capable, using two messages */
582 	MSI_FLAG_LEVEL_CAPABLE		= (1 << 18),
583 	/* MSI-X entries must be contiguous */
584 	MSI_FLAG_MSIX_CONTIGUOUS	= (1 << 19),
585 	/* PCI/MSI-X vectors can be dynamically allocated/freed post MSI-X enable */
586 	MSI_FLAG_PCI_MSIX_ALLOC_DYN	= (1 << 20),
587 	/* PCI MSIs cannot be steered separately to CPU cores */
588 	MSI_FLAG_NO_AFFINITY		= (1 << 21),
589 	/* Inhibit usage of entry masking */
590 	MSI_FLAG_NO_MASK		= (1 << 22),
591 };
592 
593 /*
594  * Flags for msi_parent_ops::chip_flags
595  */
596 enum {
597 	MSI_CHIP_FLAG_SET_EOI		= (1 << 0),
598 	MSI_CHIP_FLAG_SET_ACK		= (1 << 1),
599 };
600 
601 /**
602  * struct msi_parent_ops - MSI parent domain callbacks and configuration info
603  *
604  * @supported_flags:	Required: The supported MSI flags of the parent domain
605  * @required_flags:	Optional: The required MSI flags of the parent MSI domain
606  * @chip_flags:		Optional: Select MSI chip callbacks to update with defaults
607  *			in msi_lib_init_dev_msi_info().
608  * @bus_select_token:	Optional: The bus token of the real parent domain for
609  *			irq_domain::select()
610  * @bus_select_mask:	Optional: A mask of supported BUS_DOMAINs for
611  *			irq_domain::select()
612  * @prefix:		Optional: Prefix for the domain and chip name
613  * @init_dev_msi_info:	Required: Callback for MSI parent domains to setup parent
614  *			domain specific domain flags, domain ops and interrupt chip
615  *			callbacks when a per device domain is created.
616  */
617 struct msi_parent_ops {
618 	u32		supported_flags;
619 	u32		required_flags;
620 	u32		chip_flags;
621 	u32		bus_select_token;
622 	u32		bus_select_mask;
623 	const char	*prefix;
624 	bool		(*init_dev_msi_info)(struct device *dev, struct irq_domain *domain,
625 					     struct irq_domain *msi_parent_domain,
626 					     struct msi_domain_info *msi_child_info);
627 };
628 
629 bool msi_parent_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
630 				  struct irq_domain *msi_parent_domain,
631 				  struct msi_domain_info *msi_child_info);
632 
633 int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask,
634 			    bool force);
635 
636 struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode,
637 					 struct msi_domain_info *info,
638 					 struct irq_domain *parent);
639 
640 struct irq_domain_info;
641 struct irq_domain *msi_create_parent_irq_domain(struct irq_domain_info *info,
642 						const struct msi_parent_ops *msi_parent_ops);
643 
644 bool msi_create_device_irq_domain(struct device *dev, unsigned int domid,
645 				  const struct msi_domain_template *template,
646 				  unsigned int hwsize, void *domain_data,
647 				  void *chip_data);
648 void msi_remove_device_irq_domain(struct device *dev, unsigned int domid);
649 
650 bool msi_match_device_irq_domain(struct device *dev, unsigned int domid,
651 				 enum irq_domain_bus_token bus_token);
652 
653 int msi_domain_alloc_irqs_range_locked(struct device *dev, unsigned int domid,
654 				       unsigned int first, unsigned int last);
655 int msi_domain_alloc_irqs_range(struct device *dev, unsigned int domid,
656 				unsigned int first, unsigned int last);
657 int msi_domain_alloc_irqs_all_locked(struct device *dev, unsigned int domid, int nirqs);
658 
659 struct msi_map msi_domain_alloc_irq_at(struct device *dev, unsigned int domid, unsigned int index,
660 				       const struct irq_affinity_desc *affdesc,
661 				       union msi_instance_cookie *cookie);
662 
663 void msi_domain_free_irqs_range_locked(struct device *dev, unsigned int domid,
664 				       unsigned int first, unsigned int last);
665 void msi_domain_free_irqs_range(struct device *dev, unsigned int domid,
666 				unsigned int first, unsigned int last);
667 void msi_domain_free_irqs_all_locked(struct device *dev, unsigned int domid);
668 void msi_domain_free_irqs_all(struct device *dev, unsigned int domid);
669 
670 struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain);
671 
672 /* Per device platform MSI */
673 int platform_device_msi_init_and_alloc_irqs(struct device *dev, unsigned int nvec,
674 					    irq_write_msi_msg_t write_msi_msg);
675 void platform_device_msi_free_irqs_all(struct device *dev);
676 
677 bool msi_device_has_isolated_msi(struct device *dev);
678 
msi_domain_alloc_irqs(struct device * dev,unsigned int domid,int nirqs)679 static inline int msi_domain_alloc_irqs(struct device *dev, unsigned int domid, int nirqs)
680 {
681 	return msi_domain_alloc_irqs_range(dev, domid, 0, nirqs - 1);
682 }
683 
684 #else /* CONFIG_GENERIC_MSI_IRQ */
msi_device_has_isolated_msi(struct device * dev)685 static inline bool msi_device_has_isolated_msi(struct device *dev)
686 {
687 	/*
688 	 * Arguably if the platform does not enable MSI support then it has
689 	 * "isolated MSI", as an interrupt controller that cannot receive MSIs
690 	 * is inherently isolated by our definition. The default definition for
691 	 * arch_is_isolated_msi() is conservative and returns false anyhow.
692 	 */
693 	return arch_is_isolated_msi();
694 }
695 #endif /* CONFIG_GENERIC_MSI_IRQ */
696 
697 /* PCI specific interfaces */
698 #ifdef CONFIG_PCI_MSI
699 struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc);
700 void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg);
701 void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
702 void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
703 void pci_msi_mask_irq(struct irq_data *data);
704 void pci_msi_unmask_irq(struct irq_data *data);
705 u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev);
706 u32 pci_msi_map_rid_ctlr_node(struct irq_domain *domain, struct pci_dev *pdev,
707 			      struct fwnode_handle **node);
708 struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev);
709 void pci_msix_prepare_desc(struct irq_domain *domain, msi_alloc_info_t *arg,
710 			   struct msi_desc *desc);
711 #else /* CONFIG_PCI_MSI */
pci_msi_get_device_domain(struct pci_dev * pdev)712 static inline struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev)
713 {
714 	return NULL;
715 }
pci_write_msi_msg(unsigned int irq,struct msi_msg * msg)716 static inline void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg) { }
717 #endif /* !CONFIG_PCI_MSI */
718 
719 #endif /* LINUX_MSI_H */
720