xref: /linux-6.15/include/linux/msi.h (revision 01eadc8d)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef LINUX_MSI_H
3 #define LINUX_MSI_H
4 
5 #include <linux/kobject.h>
6 #include <linux/list.h>
7 #include <asm/msi.h>
8 
9 /* Dummy shadow structures if an architecture does not define them */
10 #ifndef arch_msi_msg_addr_lo
11 typedef struct arch_msi_msg_addr_lo {
12 	u32	address_lo;
13 } __attribute__ ((packed)) arch_msi_msg_addr_lo_t;
14 #endif
15 
16 #ifndef arch_msi_msg_addr_hi
17 typedef struct arch_msi_msg_addr_hi {
18 	u32	address_hi;
19 } __attribute__ ((packed)) arch_msi_msg_addr_hi_t;
20 #endif
21 
22 #ifndef arch_msi_msg_data
23 typedef struct arch_msi_msg_data {
24 	u32	data;
25 } __attribute__ ((packed)) arch_msi_msg_data_t;
26 #endif
27 
28 /**
29  * msi_msg - Representation of a MSI message
30  * @address_lo:		Low 32 bits of msi message address
31  * @arch_addrlo:	Architecture specific shadow of @address_lo
32  * @address_hi:		High 32 bits of msi message address
33  *			(only used when device supports it)
34  * @arch_addrhi:	Architecture specific shadow of @address_hi
35  * @data:		MSI message data (usually 16 bits)
36  * @arch_data:		Architecture specific shadow of @data
37  */
38 struct msi_msg {
39 	union {
40 		u32			address_lo;
41 		arch_msi_msg_addr_lo_t	arch_addr_lo;
42 	};
43 	union {
44 		u32			address_hi;
45 		arch_msi_msg_addr_hi_t	arch_addr_hi;
46 	};
47 	union {
48 		u32			data;
49 		arch_msi_msg_data_t	arch_data;
50 	};
51 };
52 
53 extern int pci_msi_ignore_mask;
54 /* Helper functions */
55 struct irq_data;
56 struct msi_desc;
57 struct pci_dev;
58 struct platform_msi_priv_data;
59 void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
60 #ifdef CONFIG_GENERIC_MSI_IRQ
61 void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg);
62 #else
63 static inline void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg)
64 {
65 }
66 #endif
67 
68 typedef void (*irq_write_msi_msg_t)(struct msi_desc *desc,
69 				    struct msi_msg *msg);
70 
71 /**
72  * platform_msi_desc - Platform device specific msi descriptor data
73  * @msi_priv_data:	Pointer to platform private data
74  * @msi_index:		The index of the MSI descriptor for multi MSI
75  */
76 struct platform_msi_desc {
77 	struct platform_msi_priv_data	*msi_priv_data;
78 	u16				msi_index;
79 };
80 
81 /**
82  * fsl_mc_msi_desc - FSL-MC device specific msi descriptor data
83  * @msi_index:		The index of the MSI descriptor
84  */
85 struct fsl_mc_msi_desc {
86 	u16				msi_index;
87 };
88 
89 /**
90  * ti_sci_inta_msi_desc - TISCI based INTA specific msi descriptor data
91  * @dev_index: TISCI device index
92  */
93 struct ti_sci_inta_msi_desc {
94 	u16	dev_index;
95 };
96 
97 /**
98  * struct msi_desc - Descriptor structure for MSI based interrupts
99  * @list:	List head for management
100  * @irq:	The base interrupt number
101  * @nvec_used:	The number of vectors used
102  * @dev:	Pointer to the device which uses this descriptor
103  * @msg:	The last set MSI message cached for reuse
104  * @affinity:	Optional pointer to a cpu affinity mask for this descriptor
105  *
106  * @write_msi_msg:	Callback that may be called when the MSI message
107  *			address or data changes
108  * @write_msi_msg_data:	Data parameter for the callback.
109  *
110  * @masked:	[PCI MSI/X] Mask bits
111  * @is_msix:	[PCI MSI/X] True if MSI-X
112  * @multiple:	[PCI MSI/X] log2 num of messages allocated
113  * @multi_cap:	[PCI MSI/X] log2 num of messages supported
114  * @maskbit:	[PCI MSI/X] Mask-Pending bit supported?
115  * @is_64:	[PCI MSI/X] Address size: 0=32bit 1=64bit
116  * @entry_nr:	[PCI MSI/X] Entry which is described by this descriptor
117  * @default_irq:[PCI MSI/X] The default pre-assigned non-MSI irq
118  * @mask_pos:	[PCI MSI]   Mask register position
119  * @mask_base:	[PCI MSI-X] Mask register base address
120  * @platform:	[platform]  Platform device specific msi descriptor data
121  * @fsl_mc:	[fsl-mc]    FSL MC device specific msi descriptor data
122  * @inta:	[INTA]	    TISCI based INTA specific msi descriptor data
123  */
124 struct msi_desc {
125 	/* Shared device/bus type independent data */
126 	struct list_head		list;
127 	unsigned int			irq;
128 	unsigned int			nvec_used;
129 	struct device			*dev;
130 	struct msi_msg			msg;
131 	struct irq_affinity_desc	*affinity;
132 #ifdef CONFIG_IRQ_MSI_IOMMU
133 	const void			*iommu_cookie;
134 #endif
135 
136 	void (*write_msi_msg)(struct msi_desc *entry, void *data);
137 	void *write_msi_msg_data;
138 
139 	union {
140 		/* PCI MSI/X specific data */
141 		struct {
142 			u32 masked;
143 			struct {
144 				u8	is_msix		: 1;
145 				u8	multiple	: 3;
146 				u8	multi_cap	: 3;
147 				u8	maskbit		: 1;
148 				u8	is_64		: 1;
149 				u8	is_virtual	: 1;
150 				u16	entry_nr;
151 				unsigned default_irq;
152 			} msi_attrib;
153 			union {
154 				u8	mask_pos;
155 				void __iomem *mask_base;
156 			};
157 		};
158 
159 		/*
160 		 * Non PCI variants add their data structure here. New
161 		 * entries need to use a named structure. We want
162 		 * proper name spaces for this. The PCI part is
163 		 * anonymous for now as it would require an immediate
164 		 * tree wide cleanup.
165 		 */
166 		struct platform_msi_desc platform;
167 		struct fsl_mc_msi_desc fsl_mc;
168 		struct ti_sci_inta_msi_desc inta;
169 	};
170 };
171 
172 /* Helpers to hide struct msi_desc implementation details */
173 #define msi_desc_to_dev(desc)		((desc)->dev)
174 #define dev_to_msi_list(dev)		(&(dev)->msi_list)
175 #define first_msi_entry(dev)		\
176 	list_first_entry(dev_to_msi_list((dev)), struct msi_desc, list)
177 #define for_each_msi_entry(desc, dev)	\
178 	list_for_each_entry((desc), dev_to_msi_list((dev)), list)
179 #define for_each_msi_entry_safe(desc, tmp, dev)	\
180 	list_for_each_entry_safe((desc), (tmp), dev_to_msi_list((dev)), list)
181 
182 #ifdef CONFIG_IRQ_MSI_IOMMU
183 static inline const void *msi_desc_get_iommu_cookie(struct msi_desc *desc)
184 {
185 	return desc->iommu_cookie;
186 }
187 
188 static inline void msi_desc_set_iommu_cookie(struct msi_desc *desc,
189 					     const void *iommu_cookie)
190 {
191 	desc->iommu_cookie = iommu_cookie;
192 }
193 #else
194 static inline const void *msi_desc_get_iommu_cookie(struct msi_desc *desc)
195 {
196 	return NULL;
197 }
198 
199 static inline void msi_desc_set_iommu_cookie(struct msi_desc *desc,
200 					     const void *iommu_cookie)
201 {
202 }
203 #endif
204 
205 #ifdef CONFIG_PCI_MSI
206 #define first_pci_msi_entry(pdev)	first_msi_entry(&(pdev)->dev)
207 #define for_each_pci_msi_entry(desc, pdev)	\
208 	for_each_msi_entry((desc), &(pdev)->dev)
209 
210 struct pci_dev *msi_desc_to_pci_dev(struct msi_desc *desc);
211 void *msi_desc_to_pci_sysdata(struct msi_desc *desc);
212 void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg);
213 #else /* CONFIG_PCI_MSI */
214 static inline void *msi_desc_to_pci_sysdata(struct msi_desc *desc)
215 {
216 	return NULL;
217 }
218 static inline void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg)
219 {
220 }
221 #endif /* CONFIG_PCI_MSI */
222 
223 struct msi_desc *alloc_msi_entry(struct device *dev, int nvec,
224 				 const struct irq_affinity_desc *affinity);
225 void free_msi_entry(struct msi_desc *entry);
226 void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
227 void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
228 
229 u32 __pci_msix_desc_mask_irq(struct msi_desc *desc, u32 flag);
230 u32 __pci_msi_desc_mask_irq(struct msi_desc *desc, u32 mask, u32 flag);
231 void pci_msi_mask_irq(struct irq_data *data);
232 void pci_msi_unmask_irq(struct irq_data *data);
233 
234 /*
235  * The arch hooks to setup up msi irqs. Default functions are implemented
236  * as weak symbols so that they /can/ be overriden by architecture specific
237  * code if needed. These hooks must be enabled by the architecture or by
238  * drivers which depend on them via msi_controller based MSI handling.
239  *
240  * If CONFIG_PCI_MSI_ARCH_FALLBACKS is not selected they are replaced by
241  * stubs with warnings.
242  */
243 #ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS
244 int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc);
245 void arch_teardown_msi_irq(unsigned int irq);
246 int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type);
247 void arch_teardown_msi_irqs(struct pci_dev *dev);
248 void default_teardown_msi_irqs(struct pci_dev *dev);
249 #else
250 static inline int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
251 {
252 	WARN_ON_ONCE(1);
253 	return -ENODEV;
254 }
255 
256 static inline void arch_teardown_msi_irqs(struct pci_dev *dev)
257 {
258 	WARN_ON_ONCE(1);
259 }
260 #endif
261 
262 /*
263  * The restore hooks are still available as they are useful even
264  * for fully irq domain based setups. Courtesy to XEN/X86.
265  */
266 void arch_restore_msi_irqs(struct pci_dev *dev);
267 void default_restore_msi_irqs(struct pci_dev *dev);
268 
269 struct msi_controller {
270 	struct module *owner;
271 	struct device *dev;
272 	struct device_node *of_node;
273 	struct list_head list;
274 
275 	int (*setup_irq)(struct msi_controller *chip, struct pci_dev *dev,
276 			 struct msi_desc *desc);
277 	int (*setup_irqs)(struct msi_controller *chip, struct pci_dev *dev,
278 			  int nvec, int type);
279 	void (*teardown_irq)(struct msi_controller *chip, unsigned int irq);
280 };
281 
282 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
283 
284 #include <linux/irqhandler.h>
285 
286 struct irq_domain;
287 struct irq_domain_ops;
288 struct irq_chip;
289 struct device_node;
290 struct fwnode_handle;
291 struct msi_domain_info;
292 
293 /**
294  * struct msi_domain_ops - MSI interrupt domain callbacks
295  * @get_hwirq:		Retrieve the resulting hw irq number
296  * @msi_init:		Domain specific init function for MSI interrupts
297  * @msi_free:		Domain specific function to free a MSI interrupts
298  * @msi_check:		Callback for verification of the domain/info/dev data
299  * @msi_prepare:	Prepare the allocation of the interrupts in the domain
300  * @msi_finish:		Optional callback to finalize the allocation
301  * @set_desc:		Set the msi descriptor for an interrupt
302  * @handle_error:	Optional error handler if the allocation fails
303  * @domain_alloc_irqs:	Optional function to override the default allocation
304  *			function.
305  * @domain_free_irqs:	Optional function to override the default free
306  *			function.
307  *
308  * @get_hwirq, @msi_init and @msi_free are callbacks used by
309  * msi_create_irq_domain() and related interfaces
310  *
311  * @msi_check, @msi_prepare, @msi_finish, @set_desc and @handle_error
312  * are callbacks used by msi_domain_alloc_irqs() and related
313  * interfaces which are based on msi_desc.
314  *
315  * @domain_alloc_irqs, @domain_free_irqs can be used to override the
316  * default allocation/free functions (__msi_domain_alloc/free_irqs). This
317  * is initially for a wrapper around XENs seperate MSI universe which can't
318  * be wrapped into the regular irq domains concepts by mere mortals.  This
319  * allows to universally use msi_domain_alloc/free_irqs without having to
320  * special case XEN all over the place.
321  *
322  * Contrary to other operations @domain_alloc_irqs and @domain_free_irqs
323  * are set to the default implementation if NULL and even when
324  * MSI_FLAG_USE_DEF_DOM_OPS is not set to avoid breaking existing users and
325  * because these callbacks are obviously mandatory.
326  *
327  * This is NOT meant to be abused, but it can be useful to build wrappers
328  * for specialized MSI irq domains which need extra work before and after
329  * calling __msi_domain_alloc_irqs()/__msi_domain_free_irqs().
330  */
331 struct msi_domain_ops {
332 	irq_hw_number_t	(*get_hwirq)(struct msi_domain_info *info,
333 				     msi_alloc_info_t *arg);
334 	int		(*msi_init)(struct irq_domain *domain,
335 				    struct msi_domain_info *info,
336 				    unsigned int virq, irq_hw_number_t hwirq,
337 				    msi_alloc_info_t *arg);
338 	void		(*msi_free)(struct irq_domain *domain,
339 				    struct msi_domain_info *info,
340 				    unsigned int virq);
341 	int		(*msi_check)(struct irq_domain *domain,
342 				     struct msi_domain_info *info,
343 				     struct device *dev);
344 	int		(*msi_prepare)(struct irq_domain *domain,
345 				       struct device *dev, int nvec,
346 				       msi_alloc_info_t *arg);
347 	void		(*msi_finish)(msi_alloc_info_t *arg, int retval);
348 	void		(*set_desc)(msi_alloc_info_t *arg,
349 				    struct msi_desc *desc);
350 	int		(*handle_error)(struct irq_domain *domain,
351 					struct msi_desc *desc, int error);
352 	int		(*domain_alloc_irqs)(struct irq_domain *domain,
353 					     struct device *dev, int nvec);
354 	void		(*domain_free_irqs)(struct irq_domain *domain,
355 					    struct device *dev);
356 };
357 
358 /**
359  * struct msi_domain_info - MSI interrupt domain data
360  * @flags:		Flags to decribe features and capabilities
361  * @ops:		The callback data structure
362  * @chip:		Optional: associated interrupt chip
363  * @chip_data:		Optional: associated interrupt chip data
364  * @handler:		Optional: associated interrupt flow handler
365  * @handler_data:	Optional: associated interrupt flow handler data
366  * @handler_name:	Optional: associated interrupt flow handler name
367  * @data:		Optional: domain specific data
368  */
369 struct msi_domain_info {
370 	u32			flags;
371 	struct msi_domain_ops	*ops;
372 	struct irq_chip		*chip;
373 	void			*chip_data;
374 	irq_flow_handler_t	handler;
375 	void			*handler_data;
376 	const char		*handler_name;
377 	void			*data;
378 };
379 
380 /* Flags for msi_domain_info */
381 enum {
382 	/*
383 	 * Init non implemented ops callbacks with default MSI domain
384 	 * callbacks.
385 	 */
386 	MSI_FLAG_USE_DEF_DOM_OPS	= (1 << 0),
387 	/*
388 	 * Init non implemented chip callbacks with default MSI chip
389 	 * callbacks.
390 	 */
391 	MSI_FLAG_USE_DEF_CHIP_OPS	= (1 << 1),
392 	/* Support multiple PCI MSI interrupts */
393 	MSI_FLAG_MULTI_PCI_MSI		= (1 << 2),
394 	/* Support PCI MSIX interrupts */
395 	MSI_FLAG_PCI_MSIX		= (1 << 3),
396 	/* Needs early activate, required for PCI */
397 	MSI_FLAG_ACTIVATE_EARLY		= (1 << 4),
398 	/*
399 	 * Must reactivate when irq is started even when
400 	 * MSI_FLAG_ACTIVATE_EARLY has been set.
401 	 */
402 	MSI_FLAG_MUST_REACTIVATE	= (1 << 5),
403 	/* Is level-triggered capable, using two messages */
404 	MSI_FLAG_LEVEL_CAPABLE		= (1 << 6),
405 };
406 
407 int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask,
408 			    bool force);
409 
410 struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode,
411 					 struct msi_domain_info *info,
412 					 struct irq_domain *parent);
413 int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
414 			    int nvec);
415 int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
416 			  int nvec);
417 void __msi_domain_free_irqs(struct irq_domain *domain, struct device *dev);
418 void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev);
419 struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain);
420 
421 struct irq_domain *platform_msi_create_irq_domain(struct fwnode_handle *fwnode,
422 						  struct msi_domain_info *info,
423 						  struct irq_domain *parent);
424 int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec,
425 				   irq_write_msi_msg_t write_msi_msg);
426 void platform_msi_domain_free_irqs(struct device *dev);
427 
428 /* When an MSI domain is used as an intermediate domain */
429 int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev,
430 			    int nvec, msi_alloc_info_t *args);
431 int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
432 			     int virq, int nvec, msi_alloc_info_t *args);
433 struct irq_domain *
434 __platform_msi_create_device_domain(struct device *dev,
435 				    unsigned int nvec,
436 				    bool is_tree,
437 				    irq_write_msi_msg_t write_msi_msg,
438 				    const struct irq_domain_ops *ops,
439 				    void *host_data);
440 
441 #define platform_msi_create_device_domain(dev, nvec, write, ops, data)	\
442 	__platform_msi_create_device_domain(dev, nvec, false, write, ops, data)
443 #define platform_msi_create_device_tree_domain(dev, nvec, write, ops, data) \
444 	__platform_msi_create_device_domain(dev, nvec, true, write, ops, data)
445 
446 int platform_msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
447 			      unsigned int nr_irqs);
448 void platform_msi_domain_free(struct irq_domain *domain, unsigned int virq,
449 			      unsigned int nvec);
450 void *platform_msi_get_host_data(struct irq_domain *domain);
451 #endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */
452 
453 #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
454 void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg);
455 struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode,
456 					     struct msi_domain_info *info,
457 					     struct irq_domain *parent);
458 int pci_msi_domain_check_cap(struct irq_domain *domain,
459 			     struct msi_domain_info *info, struct device *dev);
460 u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev);
461 struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev);
462 bool pci_dev_has_special_msi_domain(struct pci_dev *pdev);
463 #else
464 static inline struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev)
465 {
466 	return NULL;
467 }
468 #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */
469 
470 #endif /* LINUX_MSI_H */
471