2 # Copyright (c) 1998-2004 Doug Rabson
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29 #include <sys/types.h>
30 #include <sys/systm.h>
34 * @defgroup BUS bus - KObj methods for drivers of devices with children
35 * @brief A set of methods required device drivers that support
42 # Default implementations of some methods.
45 static struct resource *
46 null_alloc_resource(device_t dev, device_t child,
47 int type, int *rid, rman_res_t start, rman_res_t end,
48 rman_res_t count, u_int flags)
54 null_remap_intr(device_t bus, device_t dev, u_int irq)
58 return (BUS_REMAP_INTR(dev, NULL, irq));
63 null_add_child(device_t bus, int order, const char *name,
67 panic("bus_add_child is not implemented");
70 static int null_reset_post(device_t bus, device_t dev)
75 static int null_reset_prepare(device_t bus, device_t dev)
81 null_get_property(device_t dev, device_t child, const char *propname,
82 void *propvalue, size_t size)
89 * @brief Print a description of a child device
91 * This is called from system code which prints out a description of a
92 * device. It should describe the attachment that the child has with
93 * the parent. For instance the TurboLaser bus prints which node the
94 * device is attached to. See bus_generic_print_child() for more
97 * @param _dev the device whose child is being printed
98 * @param _child the child device to describe
100 * @returns the number of characters output.
102 METHOD int print_child {
105 } DEFAULT bus_generic_print_child;
108 * @brief Print a notification about an unprobed child device.
110 * Called for each child device that did not succeed in probing for a
113 * @param _dev the device whose child was being probed
114 * @param _child the child device which failed to probe
116 METHOD void probe_nomatch {
122 * @brief Read the value of a bus-specific attribute of a device
124 * This method, along with BUS_WRITE_IVAR() manages a bus-specific set
125 * of instance variables of a child device. The intention is that
126 * each different type of bus defines a set of appropriate instance
127 * variables (such as ports and irqs for ISA bus etc.)
129 * This information could be given to the child device as a struct but
130 * that makes it hard for a bus to add or remove variables without
131 * forcing an edit and recompile for all drivers which may not be
132 * possible for vendor supplied binary drivers.
134 * This method copies the value of an instance variable to the
135 * location specified by @p *_result.
137 * @param _dev the device whose child was being examined
138 * @param _child the child device whose instance variable is
140 * @param _index the instance variable to read
141 * @param _result a location to receive the instance variable
145 * @retval ENOENT no such instance variable is supported by @p
148 METHOD int read_ivar {
156 * @brief Write the value of a bus-specific attribute of a device
158 * This method sets the value of an instance variable to @p _value.
160 * @param _dev the device whose child was being updated
161 * @param _child the child device whose instance variable is
163 * @param _index the instance variable to write
164 * @param _value the value to write to that instance variable
167 * @retval ENOENT no such instance variable is supported by @p
169 * @retval EINVAL the instance variable was recognised but
170 * contains a read-only value
172 METHOD int write_ivar {
180 * @brief Notify a bus that a child was deleted
182 * Called at the beginning of device_delete_child() to allow the parent
183 * to teardown any bus-specific state for the child.
185 * @param _dev the device whose child is being deleted
186 * @param _child the child device which is being deleted
188 METHOD void child_deleted {
194 * @brief Notify a bus that a child was detached
196 * Called after the child's DEVICE_DETACH() method to allow the parent
197 * to reclaim any resources allocated on behalf of the child.
199 * @param _dev the device whose child changed state
200 * @param _child the child device which changed state
202 METHOD void child_detached {
208 * @brief Notify a bus that a new driver was added
210 * Called when a new driver is added to the devclass which owns this
211 * bus. The generic implementation of this method attempts to probe and
212 * attach any un-matched children of the bus.
214 * @param _dev the device whose devclass had a new driver
216 * @param _driver the new driver which was added
218 METHOD void driver_added {
221 } DEFAULT bus_generic_driver_added;
224 * @brief Create a new child device
226 * For buses which use use drivers supporting DEVICE_IDENTIFY() to
227 * enumerate their devices, this method is used to create new
228 * device instances. The new device will be added after the last
229 * existing child with the same order. Implementations of bus_add_child
230 * call device_add_child_ordered to add the child and often add
231 * a suitable ivar to the device specific to that bus.
233 * @param _dev the bus device which will be the parent of the
235 * @param _order a value which is used to partially sort the
236 * children of @p _dev - devices created using
237 * lower values of @p _order appear first in @p
238 * _dev's list of children
239 * @param _name devclass name for new device or @c NULL if not
241 * @param _unit unit number for new device or @c -1 if not
244 METHOD device_t add_child {
249 } DEFAULT null_add_child;
252 * @brief Rescan the bus
254 * This method is called by a parent bridge or devctl to trigger a bus
255 * rescan. The rescan should delete devices no longer present and
256 * enumerate devices that have newly arrived.
258 * @param _dev the bus device
265 * @brief Allocate a system resource
267 * This method is called by child devices of a bus to allocate resources.
268 * The types are defined in <machine/resource.h>; the meaning of the
269 * resource-ID field varies from bus to bus (but @p *rid == 0 is always
270 * valid if the resource type is). If a resource was allocated and the
271 * caller did not use the RF_ACTIVE to specify that it should be
272 * activated immediately, the caller is responsible for calling
273 * BUS_ACTIVATE_RESOURCE() when it actually uses the resource.
275 * @param _dev the parent device of @p _child
276 * @param _child the device which is requesting an allocation
277 * @param _type the type of resource to allocate
278 * @param _rid a pointer to the resource identifier
279 * @param _start hint at the start of the resource range - pass
280 * @c 0 for any start address
281 * @param _end hint at the end of the resource range - pass
282 * @c ~0 for any end address
283 * @param _count hint at the size of range required - pass @c 1
285 * @param _flags any extra flags to control the resource
286 * allocation - see @c RF_XXX flags in
287 * <sys/rman.h> for details
289 * @returns the resource which was allocated or @c NULL if no
290 * resource could be allocated
292 METHOD struct resource * alloc_resource {
301 } DEFAULT null_alloc_resource;
304 * @brief Activate a resource
306 * Activate a resource previously allocated with
307 * BUS_ALLOC_RESOURCE(). This may enable decoding of this resource in a
308 * device for instance. It will also establish a mapping for the resource
309 * unless RF_UNMAPPED was set when allocating the resource.
311 * @param _dev the parent device of @p _child
312 * @param _child the device which allocated the resource
313 * @param _type the type of resource
314 * @param _rid the resource identifier
315 * @param _r the resource to activate
317 METHOD int activate_resource {
327 * @brief Map a resource
329 * Allocate a mapping for a range of an active resource. The mapping
330 * is described by a struct resource_map object. This may for instance
331 * map a memory region into the kernel's virtual address space.
333 * @param _dev the parent device of @p _child
334 * @param _child the device which allocated the resource
335 * @param _type the type of resource
336 * @param _r the resource to map
337 * @param _args optional attributes of the mapping
338 * @param _map the mapping
340 METHOD int map_resource {
345 struct resource_map_request *_args;
346 struct resource_map *_map;
347 } DEFAULT bus_generic_map_resource;
351 * @brief Unmap a resource
353 * Release a mapping previously allocated with
354 * BUS_MAP_RESOURCE(). This may for instance unmap a memory region
355 * from the kernel's virtual address space.
357 * @param _dev the parent device of @p _child
358 * @param _child the device which allocated the resource
359 * @param _type the type of resource
360 * @param _r the resource
361 * @param _map the mapping to release
363 METHOD int unmap_resource {
368 struct resource_map *_map;
369 } DEFAULT bus_generic_unmap_resource;
373 * @brief Deactivate a resource
375 * Deactivate a resource previously allocated with
376 * BUS_ALLOC_RESOURCE().
378 * @param _dev the parent device of @p _child
379 * @param _child the device which allocated the resource
380 * @param _type the type of resource
381 * @param _rid the resource identifier
382 * @param _r the resource to deactivate
384 METHOD int deactivate_resource {
393 * @brief Adjust a resource
395 * Adjust the start and/or end of a resource allocated by
396 * BUS_ALLOC_RESOURCE. At least part of the new address range must overlap
397 * with the existing address range. If the successful, the resource's range
398 * will be adjusted to [start, end] on return.
400 * @param _dev the parent device of @p _child
401 * @param _child the device which allocated the resource
402 * @param _type the type of resource
403 * @param _res the resource to adjust
404 * @param _start the new starting address of the resource range
405 * @param _end the new ending address of the resource range
407 METHOD int adjust_resource {
411 struct resource *_res;
417 * @brief translate a resource value
419 * Give a bus driver the opportunity to translate resource ranges. If
420 * successful, the host's view of the resource starting at @p _start is
421 * returned in @p _newstart, otherwise an error is returned.
423 * @param _dev the device associated with the resource
424 * @param _type the type of resource
425 * @param _start the starting address of the resource range
426 * @param _newstart the new starting address of the resource range
428 METHOD int translate_resource {
432 rman_res_t *_newstart;
433 } DEFAULT bus_generic_translate_resource;
436 * @brief Release a resource
438 * Free a resource allocated by the BUS_ALLOC_RESOURCE. The @p _rid
439 * value must be the same as the one returned by BUS_ALLOC_RESOURCE()
440 * (which is not necessarily the same as the one the client passed).
442 * @param _dev the parent device of @p _child
443 * @param _child the device which allocated the resource
444 * @param _type the type of resource
445 * @param _rid the resource identifier
446 * @param _r the resource to release
448 METHOD int release_resource {
453 struct resource *_res;
457 * @brief Install an interrupt handler
459 * This method is used to associate an interrupt handler function with
460 * an irq resource. When the interrupt triggers, the function @p _intr
461 * will be called with the value of @p _arg as its single
462 * argument. The value returned in @p *_cookiep is used to cancel the
463 * interrupt handler - the caller should save this value to use in a
464 * future call to BUS_TEARDOWN_INTR().
466 * @param _dev the parent device of @p _child
467 * @param _child the device which allocated the resource
468 * @param _irq the resource representing the interrupt
469 * @param _flags a set of bits from enum intr_type specifying
470 * the class of interrupt
471 * @param _intr the function to call when the interrupt
473 * @param _arg a value to use as the single argument in calls
475 * @param _cookiep a pointer to a location to receive a cookie
476 * value that may be used to remove the interrupt
479 METHOD int setup_intr {
482 struct resource *_irq;
484 driver_filter_t *_filter;
485 driver_intr_t *_intr;
491 * @brief Uninstall an interrupt handler
493 * This method is used to disassociate an interrupt handler function
494 * with an irq resource. The value of @p _cookie must be the value
495 * returned from a previous call to BUS_SETUP_INTR().
497 * @param _dev the parent device of @p _child
498 * @param _child the device which allocated the resource
499 * @param _irq the resource representing the interrupt
500 * @param _cookie the cookie value returned when the interrupt
501 * was originally registered
503 METHOD int teardown_intr {
506 struct resource *_irq;
511 * @brief Suspend an interrupt handler
513 * This method is used to mark a handler as suspended in the case
514 * that the associated device is powered down and cannot be a source
515 * for the, typically shared, interrupt.
516 * The value of @p _irq must be the interrupt resource passed
517 * to a previous call to BUS_SETUP_INTR().
519 * @param _dev the parent device of @p _child
520 * @param _child the device which allocated the resource
521 * @param _irq the resource representing the interrupt
523 METHOD int suspend_intr {
526 struct resource *_irq;
527 } DEFAULT bus_generic_suspend_intr;
530 * @brief Resume an interrupt handler
532 * This method is used to clear suspended state of a handler when
533 * the associated device is powered up and can be an interrupt source
535 * The value of @p _irq must be the interrupt resource passed
536 * to a previous call to BUS_SETUP_INTR().
538 * @param _dev the parent device of @p _child
539 * @param _child the device which allocated the resource
540 * @param _irq the resource representing the interrupt
542 METHOD int resume_intr {
545 struct resource *_irq;
546 } DEFAULT bus_generic_resume_intr;
549 * @brief Define a resource which can be allocated with
550 * BUS_ALLOC_RESOURCE().
552 * This method is used by some buses (typically ISA) to allow a
553 * driver to describe a resource range that it would like to
554 * allocate. The resource defined by @p _type and @p _rid is defined
555 * to start at @p _start and to include @p _count indices in its
558 * @param _dev the parent device of @p _child
559 * @param _child the device which owns the resource
560 * @param _type the type of resource
561 * @param _rid the resource identifier
562 * @param _start the start of the resource range
563 * @param _count the size of the resource range
565 METHOD int set_resource {
575 * @brief Describe a resource
577 * This method allows a driver to examine the range used for a given
578 * resource without actually allocating it.
580 * @param _dev the parent device of @p _child
581 * @param _child the device which owns the resource
582 * @param _type the type of resource
583 * @param _rid the resource identifier
584 * @param _start the address of a location to receive the start
585 * index of the resource range
586 * @param _count the address of a location to receive the size
587 * of the resource range
589 METHOD int get_resource {
599 * @brief Delete a resource.
601 * Use this to delete a resource (possibly one previously added with
602 * BUS_SET_RESOURCE()).
604 * @param _dev the parent device of @p _child
605 * @param _child the device which owns the resource
606 * @param _type the type of resource
607 * @param _rid the resource identifier
609 METHOD void delete_resource {
617 * @brief Return a struct resource_list.
619 * Used by drivers which use bus_generic_rl_alloc_resource() etc. to
620 * implement their resource handling. It should return the resource
621 * list of the given child device.
623 * @param _dev the parent device of @p _child
624 * @param _child the device which owns the resource list
626 METHOD struct resource_list * get_resource_list {
629 } DEFAULT bus_generic_get_resource_list;
632 * @brief Is the hardware described by @p _child still attached to the
635 * This method should return 0 if the device is not present. It
636 * should return -1 if it is present. Any errors in determining
637 * should be returned as a normal errno value. Client drivers are to
638 * assume that the device is present, even if there is an error
639 * determining if it is there. Buses are to try to avoid returning
640 * errors, but newcard will return an error if the device fails to
641 * implement this method.
643 * @param _dev the parent device of @p _child
644 * @param _child the device which is being examined
646 METHOD int child_present {
649 } DEFAULT bus_generic_child_present;
652 * @brief Returns the pnp info for this device.
654 * Return it as a string, appended to @p _sb
656 * The string must be formatted as a space-separated list of
657 * name=value pairs. Names may only contain alphanumeric characters,
658 * underscores ('_') and hyphens ('-'). Values can contain any
659 * non-whitespace characters. Values containing whitespace can be
660 * quoted with double quotes ('"'). Double quotes and backslashes in
661 * quoted values can be escaped with backslashes ('\').
663 * @param _dev the parent device of @p _child
664 * @param _child the device which is being examined
665 * @param _sb sbuf for results string
667 METHOD int child_pnpinfo {
671 } DEFAULT bus_generic_child_pnpinfo;
674 * @brief Returns the location for this device.
676 * Return it as a string, appended to @p _sb
678 * The string must be formatted as a space-separated list of
679 * name=value pairs. Names may only contain alphanumeric characters,
680 * underscores ('_') and hyphens ('-'). Values can contain any
681 * non-whitespace characters. Values containing whitespace can be
682 * quoted with double quotes ('"'). Double quotes and backslashes in
683 * quoted values can be escaped with backslashes ('\').
685 * @param _dev the parent device of @p _child
686 * @param _child the device which is being examined
687 * @param _sb sbuf for results string
689 METHOD int child_location {
693 } DEFAULT bus_generic_child_location;
696 * @brief Allow drivers to request that an interrupt be bound to a specific
699 * @param _dev the parent device of @p _child
700 * @param _child the device which allocated the resource
701 * @param _irq the resource representing the interrupt
702 * @param _cpu the CPU to bind the interrupt to
704 METHOD int bind_intr {
707 struct resource *_irq;
709 } DEFAULT bus_generic_bind_intr;
712 * @brief Allow (bus) drivers to specify the trigger mode and polarity
713 * of the specified interrupt.
715 * @param _dev the bus device
716 * @param _irq the interrupt number to modify
717 * @param _trig the trigger mode required
718 * @param _pol the interrupt polarity required
720 METHOD int config_intr {
723 enum intr_trigger _trig;
724 enum intr_polarity _pol;
725 } DEFAULT bus_generic_config_intr;
728 * @brief Allow drivers to associate a description with an active
731 * @param _dev the parent device of @p _child
732 * @param _child the device which allocated the resource
733 * @param _irq the resource representing the interrupt
734 * @param _cookie the cookie value returned when the interrupt
735 * was originally registered
736 * @param _descr the description to associate with the interrupt
738 METHOD int describe_intr {
741 struct resource *_irq;
744 } DEFAULT bus_generic_describe_intr;
747 * @brief Notify a (bus) driver about a child that the hints mechanism
748 * believes it has discovered.
750 * The bus is responsible for then adding the child in the right order
751 * and discovering other things about the child. The bus driver is
752 * free to ignore this hint, to do special things, etc. It is all up
753 * to the bus driver to interpret.
755 * This method is only called in response to the parent bus asking for
756 * hinted devices to be enumerated.
758 * @param _dev the bus device
759 * @param _dname the name of the device w/o unit numbers
760 * @param _dunit the unit number of the device
762 METHOD void hinted_child {
769 * @brief Returns bus_dma_tag_t for use w/ devices on the bus.
771 * @param _dev the parent device of @p _child
772 * @param _child the device to which the tag will belong
774 METHOD bus_dma_tag_t get_dma_tag {
777 } DEFAULT bus_generic_get_dma_tag;
780 * @brief Returns bus_space_tag_t for use w/ devices on the bus.
782 * @param _dev the parent device of @p _child
783 * @param _child the device to which the tag will belong
785 METHOD bus_space_tag_t get_bus_tag {
788 } DEFAULT bus_generic_get_bus_tag;
791 * @brief Allow the bus to determine the unit number of a device.
793 * @param _dev the parent device of @p _child
794 * @param _child the device whose unit is to be wired
795 * @param _name the name of the device's new devclass
796 * @param _unitp a pointer to the device's new unit value
798 METHOD void hint_device_unit {
806 * @brief Notify a bus that the bus pass level has been changed
808 * @param _dev the bus device
810 METHOD void new_pass {
812 } DEFAULT bus_generic_new_pass;
815 * @brief Notify a bus that specified child's IRQ should be remapped.
817 * @param _dev the bus device
818 * @param _child the child device
819 * @param _irq the irq number
821 METHOD int remap_intr {
825 } DEFAULT null_remap_intr;
828 * @brief Suspend a given child
830 * @param _dev the parent device of @p _child
831 * @param _child the device to suspend
833 METHOD int suspend_child {
836 } DEFAULT bus_generic_suspend_child;
839 * @brief Resume a given child
841 * @param _dev the parent device of @p _child
842 * @param _child the device to resume
844 METHOD int resume_child {
847 } DEFAULT bus_generic_resume_child;
850 * @brief Get the VM domain handle for the given bus and child.
852 * @param _dev the bus device
853 * @param _child the child device
854 * @param _domain a pointer to the bus's domain handle identifier
856 METHOD int get_domain {
860 } DEFAULT bus_generic_get_domain;
863 * @brief Request a set of CPUs
865 * @param _dev the bus device
866 * @param _child the child device
867 * @param _op type of CPUs to request
868 * @param _setsize the size of the set passed in _cpuset
869 * @param _cpuset a pointer to a cpuset to receive the requested
872 METHOD int get_cpus {
877 struct _cpuset *_cpuset;
878 } DEFAULT bus_generic_get_cpus;
881 * @brief Prepares the given child of the bus for reset
883 * Typically bus detaches or suspends children' drivers, and then
884 * calls this method to save bus-specific information, for instance,
885 * PCI config space, which is damaged by reset.
887 * The bus_helper_reset_prepare() helper is provided to ease
888 * implementing bus reset methods.
890 * @param _dev the bus device
891 * @param _child the child device
893 METHOD int reset_prepare {
896 } DEFAULT null_reset_prepare;
899 * @brief Restores the child operations after the reset
901 * The bus_helper_reset_post() helper is provided to ease
902 * implementing bus reset methods.
904 * @param _dev the bus device
905 * @param _child the child device
907 METHOD int reset_post {
910 } DEFAULT null_reset_post;
913 * @brief Performs reset of the child
915 * @param _dev the bus device
916 * @param _child the child device
917 * @param _flags DEVF_RESET_ flags
919 METHOD int reset_child {
926 * @brief Gets child's specific property
928 * The bus_get_property can be used to access device
929 * specific properties stored on the bus. If _propvalue
930 * is NULL or _size is 0, then method only returns size
933 * @param _dev the bus device
934 * @param _child the child device
935 * @param _propname property name
936 * @param _propvalue property value destination
937 * @param _size property value size
939 * @returns size of property if successful otherwise -1
941 METHOD ssize_t get_property {
944 const char *_propname;
947 } DEFAULT null_get_property;