2 * pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or (at
12 * your option) any later version.
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/types.h>
30 #include <linux/mutex.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/pci.h>
34 #include <linux/pci-acpi.h>
35 #include <linux/pci-aspm.h>
36 #include <linux/acpi.h>
37 #include <linux/slab.h>
38 #include <acpi/acpi_bus.h>
39 #include <acpi/acpi_drivers.h>
40 #include <acpi/apei.h>
42 #define PREFIX "ACPI: "
44 #define _COMPONENT ACPI_PCI_COMPONENT
45 ACPI_MODULE_NAME("pci_root");
46 #define ACPI_PCI_ROOT_CLASS "pci_bridge"
47 #define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
48 static int acpi_pci_root_add(struct acpi_device
*device
,
49 const struct acpi_device_id
*not_used
);
50 static void acpi_pci_root_remove(struct acpi_device
*device
);
52 #define ACPI_PCIE_REQ_SUPPORT (OSC_EXT_PCI_CONFIG_SUPPORT \
53 | OSC_ACTIVE_STATE_PWR_SUPPORT \
54 | OSC_CLOCK_PWR_CAPABILITY_SUPPORT \
57 static const struct acpi_device_id root_device_ids
[] = {
62 static struct acpi_scan_handler pci_root_handler
= {
63 .ids
= root_device_ids
,
64 .attach
= acpi_pci_root_add
,
65 .detach
= acpi_pci_root_remove
,
68 static DEFINE_MUTEX(osc_lock
);
71 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
72 * @handle - the ACPI CA node in question.
74 * Note: we could make this API take a struct acpi_device * instead, but
75 * for now, it's more convenient to operate on an acpi_handle.
77 int acpi_is_root_bridge(acpi_handle handle
)
80 struct acpi_device
*device
;
82 ret
= acpi_bus_get_device(handle
, &device
);
86 ret
= acpi_match_device_ids(device
, root_device_ids
);
92 EXPORT_SYMBOL_GPL(acpi_is_root_bridge
);
95 get_root_bridge_busnr_callback(struct acpi_resource
*resource
, void *data
)
97 struct resource
*res
= data
;
98 struct acpi_resource_address64 address
;
101 status
= acpi_resource_to_address64(resource
, &address
);
102 if (ACPI_FAILURE(status
))
105 if ((address
.address_length
> 0) &&
106 (address
.resource_type
== ACPI_BUS_NUMBER_RANGE
)) {
107 res
->start
= address
.minimum
;
108 res
->end
= address
.minimum
+ address
.address_length
- 1;
114 static acpi_status
try_get_root_bridge_busnr(acpi_handle handle
,
115 struct resource
*res
)
121 acpi_walk_resources(handle
, METHOD_NAME__CRS
,
122 get_root_bridge_busnr_callback
, res
);
123 if (ACPI_FAILURE(status
))
125 if (res
->start
== -1)
130 static u8 pci_osc_uuid_str
[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
132 static acpi_status
acpi_pci_run_osc(acpi_handle handle
,
133 const u32
*capbuf
, u32
*retval
)
135 struct acpi_osc_context context
= {
136 .uuid_str
= pci_osc_uuid_str
,
139 .cap
.pointer
= (void *)capbuf
,
143 status
= acpi_run_osc(handle
, &context
);
144 if (ACPI_SUCCESS(status
)) {
145 *retval
= *((u32
*)(context
.ret
.pointer
+ 8));
146 kfree(context
.ret
.pointer
);
151 static acpi_status
acpi_pci_query_osc(struct acpi_pci_root
*root
,
156 u32 result
, capbuf
[3];
158 support
&= OSC_PCI_SUPPORT_MASKS
;
159 support
|= root
->osc_support_set
;
161 capbuf
[OSC_QUERY_TYPE
] = OSC_QUERY_ENABLE
;
162 capbuf
[OSC_SUPPORT_TYPE
] = support
;
164 *control
&= OSC_PCI_CONTROL_MASKS
;
165 capbuf
[OSC_CONTROL_TYPE
] = *control
| root
->osc_control_set
;
167 /* Run _OSC query only with existing controls. */
168 capbuf
[OSC_CONTROL_TYPE
] = root
->osc_control_set
;
171 status
= acpi_pci_run_osc(root
->device
->handle
, capbuf
, &result
);
172 if (ACPI_SUCCESS(status
)) {
173 root
->osc_support_set
= support
;
180 static acpi_status
acpi_pci_osc_support(struct acpi_pci_root
*root
, u32 flags
)
185 status
= acpi_get_handle(root
->device
->handle
, "_OSC", &tmp
);
186 if (ACPI_FAILURE(status
))
188 mutex_lock(&osc_lock
);
189 status
= acpi_pci_query_osc(root
, flags
, NULL
);
190 mutex_unlock(&osc_lock
);
194 struct acpi_pci_root
*acpi_pci_find_root(acpi_handle handle
)
196 struct acpi_pci_root
*root
;
197 struct acpi_device
*device
;
199 if (acpi_bus_get_device(handle
, &device
) ||
200 acpi_match_device_ids(device
, root_device_ids
))
203 root
= acpi_driver_data(device
);
207 EXPORT_SYMBOL_GPL(acpi_pci_find_root
);
209 struct acpi_handle_node
{
210 struct list_head node
;
215 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
216 * @handle: the handle in question
218 * Given an ACPI CA handle, the desired PCI device is located in the
219 * list of PCI devices.
221 * If the device is found, its reference count is increased and this
222 * function returns a pointer to its data structure. The caller must
223 * decrement the reference count by calling pci_dev_put().
224 * If no device is found, %NULL is returned.
226 struct pci_dev
*acpi_get_pci_dev(acpi_handle handle
)
229 unsigned long long adr
;
232 struct pci_bus
*pbus
;
233 struct pci_dev
*pdev
= NULL
;
234 struct acpi_handle_node
*node
, *tmp
;
235 struct acpi_pci_root
*root
;
236 LIST_HEAD(device_list
);
239 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
242 while (!acpi_is_root_bridge(phandle
)) {
243 node
= kzalloc(sizeof(struct acpi_handle_node
), GFP_KERNEL
);
247 INIT_LIST_HEAD(&node
->node
);
248 node
->handle
= phandle
;
249 list_add(&node
->node
, &device_list
);
251 status
= acpi_get_parent(phandle
, &phandle
);
252 if (ACPI_FAILURE(status
))
256 root
= acpi_pci_find_root(phandle
);
263 * Now, walk back down the PCI device tree until we return to our
264 * original handle. Assumes that everything between the PCI root
265 * bridge and the device we're looking for must be a P2P bridge.
267 list_for_each_entry(node
, &device_list
, node
) {
268 acpi_handle hnd
= node
->handle
;
269 status
= acpi_evaluate_integer(hnd
, "_ADR", NULL
, &adr
);
270 if (ACPI_FAILURE(status
))
272 dev
= (adr
>> 16) & 0xffff;
275 pdev
= pci_get_slot(pbus
, PCI_DEVFN(dev
, fn
));
276 if (!pdev
|| hnd
== handle
)
279 pbus
= pdev
->subordinate
;
283 * This function may be called for a non-PCI device that has a
284 * PCI parent (eg. a disk under a PCI SATA controller). In that
285 * case pdev->subordinate will be NULL for the parent.
288 dev_dbg(&pdev
->dev
, "Not a PCI-to-PCI bridge\n");
294 list_for_each_entry_safe(node
, tmp
, &device_list
, node
)
299 EXPORT_SYMBOL_GPL(acpi_get_pci_dev
);
302 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
303 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
304 * @mask: Mask of _OSC bits to request control of, place to store control mask.
305 * @req: Mask of _OSC bits the control of is essential to the caller.
307 * Run _OSC query for @mask and if that is successful, compare the returned
308 * mask of control bits with @req. If all of the @req bits are set in the
309 * returned mask, run _OSC request for it.
311 * The variable at the @mask address may be modified regardless of whether or
312 * not the function returns success. On success it will contain the mask of
313 * _OSC bits the BIOS has granted control of, but its contents are meaningless
316 acpi_status
acpi_pci_osc_control_set(acpi_handle handle
, u32
*mask
, u32 req
)
318 struct acpi_pci_root
*root
;
324 return AE_BAD_PARAMETER
;
326 ctrl
= *mask
& OSC_PCI_CONTROL_MASKS
;
327 if ((ctrl
& req
) != req
)
330 root
= acpi_pci_find_root(handle
);
334 status
= acpi_get_handle(handle
, "_OSC", &tmp
);
335 if (ACPI_FAILURE(status
))
338 mutex_lock(&osc_lock
);
340 *mask
= ctrl
| root
->osc_control_set
;
341 /* No need to evaluate _OSC if the control was already granted. */
342 if ((root
->osc_control_set
& ctrl
) == ctrl
)
345 /* Need to check the available controls bits before requesting them. */
347 status
= acpi_pci_query_osc(root
, root
->osc_support_set
, mask
);
348 if (ACPI_FAILURE(status
))
355 if ((ctrl
& req
) != req
) {
360 capbuf
[OSC_QUERY_TYPE
] = 0;
361 capbuf
[OSC_SUPPORT_TYPE
] = root
->osc_support_set
;
362 capbuf
[OSC_CONTROL_TYPE
] = ctrl
;
363 status
= acpi_pci_run_osc(handle
, capbuf
, mask
);
364 if (ACPI_SUCCESS(status
))
365 root
->osc_control_set
= *mask
;
367 mutex_unlock(&osc_lock
);
370 EXPORT_SYMBOL(acpi_pci_osc_control_set
);
372 static int acpi_pci_root_add(struct acpi_device
*device
,
373 const struct acpi_device_id
*not_used
)
375 unsigned long long segment
, bus
;
378 struct acpi_pci_root
*root
;
379 u32 flags
, base_flags
;
380 acpi_handle handle
= device
->handle
;
381 bool no_aspm
= false, clear_aspm
= false;
383 root
= kzalloc(sizeof(struct acpi_pci_root
), GFP_KERNEL
);
388 status
= acpi_evaluate_integer(handle
, METHOD_NAME__SEG
, NULL
,
390 if (ACPI_FAILURE(status
) && status
!= AE_NOT_FOUND
) {
391 dev_err(&device
->dev
, "can't evaluate _SEG\n");
396 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
397 root
->secondary
.flags
= IORESOURCE_BUS
;
398 status
= try_get_root_bridge_busnr(handle
, &root
->secondary
);
399 if (ACPI_FAILURE(status
)) {
401 * We need both the start and end of the downstream bus range
402 * to interpret _CBA (MMCONFIG base address), so it really is
403 * supposed to be in _CRS. If we don't find it there, all we
404 * can do is assume [_BBN-0xFF] or [0-0xFF].
406 root
->secondary
.end
= 0xFF;
407 dev_warn(&device
->dev
,
408 FW_BUG
"no secondary bus range in _CRS\n");
409 status
= acpi_evaluate_integer(handle
, METHOD_NAME__BBN
,
411 if (ACPI_SUCCESS(status
))
412 root
->secondary
.start
= bus
;
413 else if (status
== AE_NOT_FOUND
)
414 root
->secondary
.start
= 0;
416 dev_err(&device
->dev
, "can't evaluate _BBN\n");
422 root
->device
= device
;
423 root
->segment
= segment
& 0xFFFF;
424 strcpy(acpi_device_name(device
), ACPI_PCI_ROOT_DEVICE_NAME
);
425 strcpy(acpi_device_class(device
), ACPI_PCI_ROOT_CLASS
);
426 device
->driver_data
= root
;
428 pr_info(PREFIX
"%s [%s] (domain %04x %pR)\n",
429 acpi_device_name(device
), acpi_device_bid(device
),
430 root
->segment
, &root
->secondary
);
432 root
->mcfg_addr
= acpi_pci_root_get_mcfg_addr(handle
);
435 * All supported architectures that use ACPI have support for
436 * PCI domains, so we indicate this in _OSC support capabilities.
438 flags
= base_flags
= OSC_PCI_SEGMENT_GROUPS_SUPPORT
;
439 acpi_pci_osc_support(root
, flags
);
441 if (pci_ext_cfg_avail())
442 flags
|= OSC_EXT_PCI_CONFIG_SUPPORT
;
443 if (pcie_aspm_support_enabled()) {
444 flags
|= OSC_ACTIVE_STATE_PWR_SUPPORT
|
445 OSC_CLOCK_PWR_CAPABILITY_SUPPORT
;
447 if (pci_msi_enabled())
448 flags
|= OSC_MSI_SUPPORT
;
449 if (flags
!= base_flags
) {
450 status
= acpi_pci_osc_support(root
, flags
);
451 if (ACPI_FAILURE(status
)) {
452 dev_info(&device
->dev
, "ACPI _OSC support "
453 "notification failed, disabling PCIe ASPM\n");
459 if (!pcie_ports_disabled
460 && (flags
& ACPI_PCIE_REQ_SUPPORT
) == ACPI_PCIE_REQ_SUPPORT
) {
461 flags
= OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
462 | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
463 | OSC_PCI_EXPRESS_PME_CONTROL
;
465 if (pci_aer_available()) {
466 if (aer_acpi_firmware_first())
467 dev_dbg(&device
->dev
,
468 "PCIe errors handled by BIOS.\n");
470 flags
|= OSC_PCI_EXPRESS_AER_CONTROL
;
473 dev_info(&device
->dev
,
474 "Requesting ACPI _OSC control (0x%02x)\n", flags
);
476 status
= acpi_pci_osc_control_set(handle
, &flags
,
477 OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
);
478 if (ACPI_SUCCESS(status
)) {
479 dev_info(&device
->dev
,
480 "ACPI _OSC control (0x%02x) granted\n", flags
);
481 if (acpi_gbl_FADT
.boot_flags
& ACPI_FADT_NO_ASPM
) {
483 * We have ASPM control, but the FADT indicates
484 * that it's unsupported. Clear it.
489 dev_info(&device
->dev
,
490 "ACPI _OSC request failed (%s), "
491 "returned control mask: 0x%02x\n",
492 acpi_format_exception(status
), flags
);
493 dev_info(&device
->dev
,
494 "ACPI _OSC control for PCIe not granted, disabling ASPM\n");
496 * We want to disable ASPM here, but aspm_disabled
497 * needs to remain in its state from boot so that we
498 * properly handle PCIe 1.1 devices. So we set this
499 * flag here, to defer the action until after the ACPI
505 dev_info(&device
->dev
,
506 "Unable to request _OSC control "
507 "(_OSC support mask: 0x%02x)\n", flags
);
511 * TBD: Need PCI interface for enumeration/configuration of roots.
515 * Scan the Root Bridge
516 * --------------------
517 * Must do this prior to any attempt to bind the root device, as the
518 * PCI namespace does not get created until this call is made (and
519 * thus the root bridge's pci_dev does not exist).
521 root
->bus
= pci_acpi_scan_root(root
);
523 dev_err(&device
->dev
,
524 "Bus %04x:%02x not present in PCI namespace\n",
525 root
->segment
, (unsigned int)root
->secondary
.start
);
531 dev_info(&device
->dev
, "Disabling ASPM (FADT indicates it is unsupported)\n");
532 pcie_clear_aspm(root
->bus
);
537 pci_acpi_add_bus_pm_notifier(device
, root
->bus
);
538 if (device
->wakeup
.flags
.run_wake
)
539 device_set_run_wake(root
->bus
->bridge
, true);
541 if (system_state
!= SYSTEM_BOOTING
) {
542 pcibios_resource_survey_bus(root
->bus
);
543 pci_assign_unassigned_root_bus_resources(root
->bus
);
546 pci_bus_add_devices(root
->bus
);
554 static void acpi_pci_root_remove(struct acpi_device
*device
)
556 struct acpi_pci_root
*root
= acpi_driver_data(device
);
558 pci_stop_root_bus(root
->bus
);
560 device_set_run_wake(root
->bus
->bridge
, false);
561 pci_acpi_remove_bus_pm_notifier(device
);
563 pci_remove_root_bus(root
->bus
);
568 void __init
acpi_pci_root_init(void)
572 if (!acpi_pci_disabled
) {
573 pci_acpi_crs_quirks();
574 acpi_scan_add_handler(&pci_root_handler
);
577 /* Support root bridge hotplug */
579 static void handle_root_bridge_insertion(acpi_handle handle
)
581 struct acpi_device
*device
;
583 if (!acpi_bus_get_device(handle
, &device
)) {
584 dev_printk(KERN_DEBUG
, &device
->dev
,
585 "acpi device already exists; ignoring notify\n");
589 if (acpi_bus_scan(handle
))
590 acpi_handle_err(handle
, "cannot add bridge to acpi list\n");
593 static void handle_root_bridge_removal(struct acpi_device
*device
)
596 struct acpi_eject_event
*ej_event
;
598 ej_event
= kmalloc(sizeof(*ej_event
), GFP_KERNEL
);
600 /* Inform firmware the hot-remove operation has error */
601 (void) acpi_evaluate_hotplug_ost(device
->handle
,
602 ACPI_NOTIFY_EJECT_REQUEST
,
603 ACPI_OST_SC_NON_SPECIFIC_FAILURE
,
608 ej_event
->device
= device
;
609 ej_event
->event
= ACPI_NOTIFY_EJECT_REQUEST
;
611 status
= acpi_os_hotplug_execute(acpi_bus_hot_remove_device
, ej_event
);
612 if (ACPI_FAILURE(status
))
616 static void _handle_hotplug_event_root(struct work_struct
*work
)
618 struct acpi_pci_root
*root
;
619 struct acpi_hp_work
*hp_work
;
623 hp_work
= container_of(work
, struct acpi_hp_work
, work
);
624 handle
= hp_work
->handle
;
625 type
= hp_work
->type
;
627 acpi_scan_lock_acquire();
629 root
= acpi_pci_find_root(handle
);
632 case ACPI_NOTIFY_BUS_CHECK
:
634 acpi_handle_printk(KERN_DEBUG
, handle
,
635 "Bus check notify on %s\n", __func__
);
637 acpiphp_check_host_bridge(handle
);
639 handle_root_bridge_insertion(handle
);
643 case ACPI_NOTIFY_DEVICE_CHECK
:
645 acpi_handle_printk(KERN_DEBUG
, handle
,
646 "Device check notify on %s\n", __func__
);
648 handle_root_bridge_insertion(handle
);
651 case ACPI_NOTIFY_EJECT_REQUEST
:
652 /* request device eject */
653 acpi_handle_printk(KERN_DEBUG
, handle
,
654 "Device eject notify on %s\n", __func__
);
656 handle_root_bridge_removal(root
->device
);
659 acpi_handle_warn(handle
,
660 "notify_handler: unknown event type 0x%x\n",
665 acpi_scan_lock_release();
666 kfree(hp_work
); /* allocated in handle_hotplug_event_bridge */
669 static void handle_hotplug_event_root(acpi_handle handle
, u32 type
,
672 alloc_acpi_hp_work(handle
, type
, context
,
673 _handle_hotplug_event_root
);
676 static acpi_status __init
677 find_root_bridges(acpi_handle handle
, u32 lvl
, void *context
, void **rv
)
680 int *count
= (int *)context
;
682 if (!acpi_is_root_bridge(handle
))
687 status
= acpi_install_notify_handler(handle
, ACPI_SYSTEM_NOTIFY
,
688 handle_hotplug_event_root
, NULL
);
689 if (ACPI_FAILURE(status
))
690 acpi_handle_printk(KERN_DEBUG
, handle
,
691 "notify handler is not installed, exit status: %u\n",
692 (unsigned int)status
);
694 acpi_handle_printk(KERN_DEBUG
, handle
,
695 "notify handler is installed\n");
700 void __init
acpi_pci_root_hp_init(void)
704 acpi_walk_namespace(ACPI_TYPE_DEVICE
, ACPI_ROOT_OBJECT
,
705 ACPI_UINT32_MAX
, find_root_bridges
, NULL
, &num
, NULL
);
707 printk(KERN_DEBUG
"Found %d acpi root devices\n", num
);