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)
82 * @brief Print a description of a child device
84 * This is called from system code which prints out a description of a
85 * device. It should describe the attachment that the child has with
86 * the parent. For instance the TurboLaser bus prints which node the
87 * device is attached to. See bus_generic_print_child() for more
90 * @param _dev the device whose child is being printed
91 * @param _child the child device to describe
93 * @returns the number of characters output.
95 METHOD int print_child {
98 } DEFAULT bus_generic_print_child;
101 * @brief Print a notification about an unprobed child device.
103 * Called for each child device that did not succeed in probing for a
106 * @param _dev the device whose child was being probed
107 * @param _child the child device which failed to probe
109 METHOD void probe_nomatch {
115 * @brief Read the value of a bus-specific attribute of a device
117 * This method, along with BUS_WRITE_IVAR() manages a bus-specific set
118 * of instance variables of a child device. The intention is that
119 * each different type of bus defines a set of appropriate instance
120 * variables (such as ports and irqs for ISA bus etc.)
122 * This information could be given to the child device as a struct but
123 * that makes it hard for a bus to add or remove variables without
124 * forcing an edit and recompile for all drivers which may not be
125 * possible for vendor supplied binary drivers.
127 * This method copies the value of an instance variable to the
128 * location specified by @p *_result.
130 * @param _dev the device whose child was being examined
131 * @param _child the child device whose instance variable is
133 * @param _index the instance variable to read
134 * @param _result a location to receive the instance variable
138 * @retval ENOENT no such instance variable is supported by @p
141 METHOD int read_ivar {
149 * @brief Write the value of a bus-specific attribute of a device
151 * This method sets the value of an instance variable to @p _value.
153 * @param _dev the device whose child was being updated
154 * @param _child the child device whose instance variable is
156 * @param _index the instance variable to write
157 * @param _value the value to write to that instance variable
160 * @retval ENOENT no such instance variable is supported by @p
162 * @retval EINVAL the instance variable was recognised but
163 * contains a read-only value
165 METHOD int write_ivar {
173 * @brief Notify a bus that a child was deleted
175 * Called at the beginning of device_delete_child() to allow the parent
176 * to teardown any bus-specific state for the child.
178 * @param _dev the device whose child is being deleted
179 * @param _child the child device which is being deleted
181 METHOD void child_deleted {
187 * @brief Notify a bus that a child was detached
189 * Called after the child's DEVICE_DETACH() method to allow the parent
190 * to reclaim any resources allocated on behalf of the child.
192 * @param _dev the device whose child changed state
193 * @param _child the child device which changed state
195 METHOD void child_detached {
201 * @brief Notify a bus that a new driver was added
203 * Called when a new driver is added to the devclass which owns this
204 * bus. The generic implementation of this method attempts to probe and
205 * attach any un-matched children of the bus.
207 * @param _dev the device whose devclass had a new driver
209 * @param _driver the new driver which was added
211 METHOD void driver_added {
214 } DEFAULT bus_generic_driver_added;
217 * @brief Create a new child device
219 * For buses which use use drivers supporting DEVICE_IDENTIFY() to
220 * enumerate their devices, this method is used to create new
221 * device instances. The new device will be added after the last
222 * existing child with the same order. Implementations of bus_add_child
223 * call device_add_child_ordered to add the child and often add
224 * a suitable ivar to the device specific to that bus.
226 * @param _dev the bus device which will be the parent of the
228 * @param _order a value which is used to partially sort the
229 * children of @p _dev - devices created using
230 * lower values of @p _order appear first in @p
231 * _dev's list of children
232 * @param _name devclass name for new device or @c NULL if not
234 * @param _unit unit number for new device or @c -1 if not
237 METHOD device_t add_child {
242 } DEFAULT null_add_child;
245 * @brief Rescan the bus
247 * This method is called by a parent bridge or devctl to trigger a bus
248 * rescan. The rescan should delete devices no longer present and
249 * enumerate devices that have newly arrived.
251 * @param _dev the bus device
258 * @brief Allocate a system resource
260 * This method is called by child devices of a bus to allocate resources.
261 * The types are defined in <machine/resource.h>; the meaning of the
262 * resource-ID field varies from bus to bus (but @p *rid == 0 is always
263 * valid if the resource type is). If a resource was allocated and the
264 * caller did not use the RF_ACTIVE to specify that it should be
265 * activated immediately, the caller is responsible for calling
266 * BUS_ACTIVATE_RESOURCE() when it actually uses the resource.
268 * @param _dev the parent device of @p _child
269 * @param _child the device which is requesting an allocation
270 * @param _type the type of resource to allocate
271 * @param _rid a pointer to the resource identifier
272 * @param _start hint at the start of the resource range - pass
273 * @c 0 for any start address
274 * @param _end hint at the end of the resource range - pass
275 * @c ~0 for any end address
276 * @param _count hint at the size of range required - pass @c 1
278 * @param _flags any extra flags to control the resource
279 * allocation - see @c RF_XXX flags in
280 * <sys/rman.h> for details
282 * @returns the resource which was allocated or @c NULL if no
283 * resource could be allocated
285 METHOD struct resource * alloc_resource {
294 } DEFAULT null_alloc_resource;
297 * @brief Activate a resource
299 * Activate a resource previously allocated with
300 * BUS_ALLOC_RESOURCE(). This may enable decoding of this resource in a
301 * device for instance. It will also establish a mapping for the resource
302 * unless RF_UNMAPPED was set when allocating the resource.
304 * @param _dev the parent device of @p _child
305 * @param _child the device which allocated the resource
306 * @param _type the type of resource
307 * @param _rid the resource identifier
308 * @param _r the resource to activate
310 METHOD int activate_resource {
320 * @brief Map a resource
322 * Allocate a mapping for a range of an active resource. The mapping
323 * is described by a struct resource_map object. This may for instance
324 * map a memory region into the kernel's virtual address space.
326 * @param _dev the parent device of @p _child
327 * @param _child the device which allocated the resource
328 * @param _type the type of resource
329 * @param _r the resource to map
330 * @param _args optional attributes of the mapping
331 * @param _map the mapping
333 METHOD int map_resource {
338 struct resource_map_request *_args;
339 struct resource_map *_map;
340 } DEFAULT bus_generic_map_resource;
344 * @brief Unmap a resource
346 * Release a mapping previously allocated with
347 * BUS_MAP_RESOURCE(). This may for instance unmap a memory region
348 * from the kernel's virtual address space.
350 * @param _dev the parent device of @p _child
351 * @param _child the device which allocated the resource
352 * @param _type the type of resource
353 * @param _r the resource
354 * @param _map the mapping to release
356 METHOD int unmap_resource {
361 struct resource_map *_map;
362 } DEFAULT bus_generic_unmap_resource;
366 * @brief Deactivate a resource
368 * Deactivate a resource previously allocated with
369 * BUS_ALLOC_RESOURCE().
371 * @param _dev the parent device of @p _child
372 * @param _child the device which allocated the resource
373 * @param _type the type of resource
374 * @param _rid the resource identifier
375 * @param _r the resource to deactivate
377 METHOD int deactivate_resource {
386 * @brief Adjust a resource
388 * Adjust the start and/or end of a resource allocated by
389 * BUS_ALLOC_RESOURCE. At least part of the new address range must overlap
390 * with the existing address range. If the successful, the resource's range
391 * will be adjusted to [start, end] on return.
393 * @param _dev the parent device of @p _child
394 * @param _child the device which allocated the resource
395 * @param _type the type of resource
396 * @param _res the resource to adjust
397 * @param _start the new starting address of the resource range
398 * @param _end the new ending address of the resource range
400 METHOD int adjust_resource {
404 struct resource *_res;
410 * @brief Release a resource
412 * Free a resource allocated by the BUS_ALLOC_RESOURCE. The @p _rid
413 * value must be the same as the one returned by BUS_ALLOC_RESOURCE()
414 * (which is not necessarily the same as the one the client passed).
416 * @param _dev the parent device of @p _child
417 * @param _child the device which allocated the resource
418 * @param _type the type of resource
419 * @param _rid the resource identifier
420 * @param _r the resource to release
422 METHOD int release_resource {
427 struct resource *_res;
431 * @brief Install an interrupt handler
433 * This method is used to associate an interrupt handler function with
434 * an irq resource. When the interrupt triggers, the function @p _intr
435 * will be called with the value of @p _arg as its single
436 * argument. The value returned in @p *_cookiep is used to cancel the
437 * interrupt handler - the caller should save this value to use in a
438 * future call to BUS_TEARDOWN_INTR().
440 * @param _dev the parent device of @p _child
441 * @param _child the device which allocated the resource
442 * @param _irq the resource representing the interrupt
443 * @param _flags a set of bits from enum intr_type specifying
444 * the class of interrupt
445 * @param _intr the function to call when the interrupt
447 * @param _arg a value to use as the single argument in calls
449 * @param _cookiep a pointer to a location to receive a cookie
450 * value that may be used to remove the interrupt
453 METHOD int setup_intr {
456 struct resource *_irq;
458 driver_filter_t *_filter;
459 driver_intr_t *_intr;
465 * @brief Uninstall an interrupt handler
467 * This method is used to disassociate an interrupt handler function
468 * with an irq resource. The value of @p _cookie must be the value
469 * returned from a previous call to BUS_SETUP_INTR().
471 * @param _dev the parent device of @p _child
472 * @param _child the device which allocated the resource
473 * @param _irq the resource representing the interrupt
474 * @param _cookie the cookie value returned when the interrupt
475 * was originally registered
477 METHOD int teardown_intr {
480 struct resource *_irq;
485 * @brief Suspend an interrupt handler
487 * This method is used to mark a handler as suspended in the case
488 * that the associated device is powered down and cannot be a source
489 * for the, typically shared, interrupt.
490 * The value of @p _irq must be the interrupt resource passed
491 * to a previous call to BUS_SETUP_INTR().
493 * @param _dev the parent device of @p _child
494 * @param _child the device which allocated the resource
495 * @param _irq the resource representing the interrupt
497 METHOD int suspend_intr {
500 struct resource *_irq;
501 } DEFAULT bus_generic_suspend_intr;
504 * @brief Resume an interrupt handler
506 * This method is used to clear suspended state of a handler when
507 * the associated device is powered up and can be an interrupt source
509 * The value of @p _irq must be the interrupt resource passed
510 * to a previous call to BUS_SETUP_INTR().
512 * @param _dev the parent device of @p _child
513 * @param _child the device which allocated the resource
514 * @param _irq the resource representing the interrupt
516 METHOD int resume_intr {
519 struct resource *_irq;
520 } DEFAULT bus_generic_resume_intr;
523 * @brief Define a resource which can be allocated with
524 * BUS_ALLOC_RESOURCE().
526 * This method is used by some buses (typically ISA) to allow a
527 * driver to describe a resource range that it would like to
528 * allocate. The resource defined by @p _type and @p _rid is defined
529 * to start at @p _start and to include @p _count indices in its
532 * @param _dev the parent device of @p _child
533 * @param _child the device which owns the resource
534 * @param _type the type of resource
535 * @param _rid the resource identifier
536 * @param _start the start of the resource range
537 * @param _count the size of the resource range
539 METHOD int set_resource {
549 * @brief Describe a resource
551 * This method allows a driver to examine the range used for a given
552 * resource without actually allocating it.
554 * @param _dev the parent device of @p _child
555 * @param _child the device which owns the resource
556 * @param _type the type of resource
557 * @param _rid the resource identifier
558 * @param _start the address of a location to receive the start
559 * index of the resource range
560 * @param _count the address of a location to receive the size
561 * of the resource range
563 METHOD int get_resource {
573 * @brief Delete a resource.
575 * Use this to delete a resource (possibly one previously added with
576 * BUS_SET_RESOURCE()).
578 * @param _dev the parent device of @p _child
579 * @param _child the device which owns the resource
580 * @param _type the type of resource
581 * @param _rid the resource identifier
583 METHOD void delete_resource {
591 * @brief Return a struct resource_list.
593 * Used by drivers which use bus_generic_rl_alloc_resource() etc. to
594 * implement their resource handling. It should return the resource
595 * list of the given child device.
597 * @param _dev the parent device of @p _child
598 * @param _child the device which owns the resource list
600 METHOD struct resource_list * get_resource_list {
603 } DEFAULT bus_generic_get_resource_list;
606 * @brief Is the hardware described by @p _child still attached to the
609 * This method should return 0 if the device is not present. It
610 * should return -1 if it is present. Any errors in determining
611 * should be returned as a normal errno value. Client drivers are to
612 * assume that the device is present, even if there is an error
613 * determining if it is there. Buses are to try to avoid returning
614 * errors, but newcard will return an error if the device fails to
615 * implement this method.
617 * @param _dev the parent device of @p _child
618 * @param _child the device which is being examined
620 METHOD int child_present {
623 } DEFAULT bus_generic_child_present;
626 * @brief Returns the pnp info for this device.
628 * Return it as a string. If the storage is insufficient for the
629 * string, then return EOVERFLOW.
631 * The string must be formatted as a space-separated list of
632 * name=value pairs. Names may only contain alphanumeric characters,
633 * underscores ('_') and hyphens ('-'). Values can contain any
634 * non-whitespace characters. Values containing whitespace can be
635 * quoted with double quotes ('"'). Double quotes and backslashes in
636 * quoted values can be escaped with backslashes ('\').
638 * @param _dev the parent device of @p _child
639 * @param _child the device which is being examined
640 * @param _buf the address of a buffer to receive the pnp
642 * @param _buflen the size of the buffer pointed to by @p _buf
644 METHOD int child_pnpinfo_str {
652 * @brief Returns the location for this device.
654 * Return it as a string. If the storage is insufficient for the
655 * string, then return EOVERFLOW.
657 * The string must be formatted as a space-separated list of
658 * name=value pairs. Names may only contain alphanumeric characters,
659 * underscores ('_') and hyphens ('-'). Values can contain any
660 * non-whitespace characters. Values containing whitespace can be
661 * quoted with double quotes ('"'). Double quotes and backslashes in
662 * quoted values can be escaped with backslashes ('\').
664 * @param _dev the parent device of @p _child
665 * @param _child the device which is being examined
666 * @param _buf the address of a buffer to receive the location
668 * @param _buflen the size of the buffer pointed to by @p _buf
670 METHOD int child_location_str {
678 * @brief Allow drivers to request that an interrupt be bound to a specific
681 * @param _dev the parent device of @p _child
682 * @param _child the device which allocated the resource
683 * @param _irq the resource representing the interrupt
684 * @param _cpu the CPU to bind the interrupt to
686 METHOD int bind_intr {
689 struct resource *_irq;
691 } DEFAULT bus_generic_bind_intr;
694 * @brief Allow (bus) drivers to specify the trigger mode and polarity
695 * of the specified interrupt.
697 * @param _dev the bus device
698 * @param _irq the interrupt number to modify
699 * @param _trig the trigger mode required
700 * @param _pol the interrupt polarity required
702 METHOD int config_intr {
705 enum intr_trigger _trig;
706 enum intr_polarity _pol;
707 } DEFAULT bus_generic_config_intr;
710 * @brief Allow drivers to associate a description with an active
713 * @param _dev the parent device of @p _child
714 * @param _child the device which allocated the resource
715 * @param _irq the resource representing the interrupt
716 * @param _cookie the cookie value returned when the interrupt
717 * was originally registered
718 * @param _descr the description to associate with the interrupt
720 METHOD int describe_intr {
723 struct resource *_irq;
726 } DEFAULT bus_generic_describe_intr;
729 * @brief Notify a (bus) driver about a child that the hints mechanism
730 * believes it has discovered.
732 * The bus is responsible for then adding the child in the right order
733 * and discovering other things about the child. The bus driver is
734 * free to ignore this hint, to do special things, etc. It is all up
735 * to the bus driver to interpret.
737 * This method is only called in response to the parent bus asking for
738 * hinted devices to be enumerated.
740 * @param _dev the bus device
741 * @param _dname the name of the device w/o unit numbers
742 * @param _dunit the unit number of the device
744 METHOD void hinted_child {
751 * @brief Returns bus_dma_tag_t for use w/ devices on the bus.
753 * @param _dev the parent device of @p _child
754 * @param _child the device to which the tag will belong
756 METHOD bus_dma_tag_t get_dma_tag {
759 } DEFAULT bus_generic_get_dma_tag;
762 * @brief Returns bus_space_tag_t for use w/ devices on the bus.
764 * @param _dev the parent device of @p _child
765 * @param _child the device to which the tag will belong
767 METHOD bus_space_tag_t get_bus_tag {
770 } DEFAULT bus_generic_get_bus_tag;
773 * @brief Allow the bus to determine the unit number of a device.
775 * @param _dev the parent device of @p _child
776 * @param _child the device whose unit is to be wired
777 * @param _name the name of the device's new devclass
778 * @param _unitp a pointer to the device's new unit value
780 METHOD void hint_device_unit {
788 * @brief Notify a bus that the bus pass level has been changed
790 * @param _dev the bus device
792 METHOD void new_pass {
794 } DEFAULT bus_generic_new_pass;
797 * @brief Notify a bus that specified child's IRQ should be remapped.
799 * @param _dev the bus device
800 * @param _child the child device
801 * @param _irq the irq number
803 METHOD int remap_intr {
807 } DEFAULT null_remap_intr;
810 * @brief Suspend a given child
812 * @param _dev the parent device of @p _child
813 * @param _child the device to suspend
815 METHOD int suspend_child {
818 } DEFAULT bus_generic_suspend_child;
821 * @brief Resume a given child
823 * @param _dev the parent device of @p _child
824 * @param _child the device to resume
826 METHOD int resume_child {
829 } DEFAULT bus_generic_resume_child;
832 * @brief Get the VM domain handle for the given bus and child.
834 * @param _dev the bus device
835 * @param _child the child device
836 * @param _domain a pointer to the bus's domain handle identifier
838 METHOD int get_domain {
842 } DEFAULT bus_generic_get_domain;
845 * @brief Request a set of CPUs
847 * @param _dev the bus device
848 * @param _child the child device
849 * @param _op type of CPUs to request
850 * @param _setsize the size of the set passed in _cpuset
851 * @param _cpuset a pointer to a cpuset to receive the requested
854 METHOD int get_cpus {
860 } DEFAULT bus_generic_get_cpus;
863 * @brief Prepares the given child of the bus for reset
865 * Typically bus detaches or suspends children' drivers, and then
866 * calls this method to save bus-specific information, for instance,
867 * PCI config space, which is damaged by reset.
869 * The bus_helper_reset_prepare() helper is provided to ease
870 * implementing bus reset methods.
872 * @param _dev the bus device
873 * @param _child the child device
875 METHOD int reset_prepare {
878 } DEFAULT null_reset_prepare;
881 * @brief Restores the child operations after the reset
883 * The bus_helper_reset_post() helper is provided to ease
884 * implementing bus reset methods.
886 * @param _dev the bus device
887 * @param _child the child device
889 METHOD int reset_post {
892 } DEFAULT null_reset_post;
895 * @brief Performs reset of the child
897 * @param _dev the bus device
898 * @param _child the child device
899 * @param _flags DEVF_RESET_ flags
901 METHOD int reset_child {