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>
44 #define PREFIX "ACPI: "
46 #define _COMPONENT ACPI_PCI_COMPONENT
47 ACPI_MODULE_NAME("pci_root");
48 #define ACPI_PCI_ROOT_CLASS "pci_bridge"
49 #define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
50 static int acpi_pci_root_add(struct acpi_device
*device
,
51 const struct acpi_device_id
*not_used
);
52 static void acpi_pci_root_remove(struct acpi_device
*device
);
54 #define ACPI_PCIE_REQ_SUPPORT (OSC_EXT_PCI_CONFIG_SUPPORT \
55 | OSC_ACTIVE_STATE_PWR_SUPPORT \
56 | OSC_CLOCK_PWR_CAPABILITY_SUPPORT \
59 static const struct acpi_device_id root_device_ids
[] = {
64 static struct acpi_scan_handler pci_root_handler
= {
65 .ids
= root_device_ids
,
66 .attach
= acpi_pci_root_add
,
67 .detach
= acpi_pci_root_remove
,
70 static DEFINE_MUTEX(osc_lock
);
73 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
74 * @handle - the ACPI CA node in question.
76 * Note: we could make this API take a struct acpi_device * instead, but
77 * for now, it's more convenient to operate on an acpi_handle.
79 int acpi_is_root_bridge(acpi_handle handle
)
82 struct acpi_device
*device
;
84 ret
= acpi_bus_get_device(handle
, &device
);
88 ret
= acpi_match_device_ids(device
, root_device_ids
);
94 EXPORT_SYMBOL_GPL(acpi_is_root_bridge
);
97 get_root_bridge_busnr_callback(struct acpi_resource
*resource
, void *data
)
99 struct resource
*res
= data
;
100 struct acpi_resource_address64 address
;
103 status
= acpi_resource_to_address64(resource
, &address
);
104 if (ACPI_FAILURE(status
))
107 if ((address
.address_length
> 0) &&
108 (address
.resource_type
== ACPI_BUS_NUMBER_RANGE
)) {
109 res
->start
= address
.minimum
;
110 res
->end
= address
.minimum
+ address
.address_length
- 1;
116 static acpi_status
try_get_root_bridge_busnr(acpi_handle handle
,
117 struct resource
*res
)
123 acpi_walk_resources(handle
, METHOD_NAME__CRS
,
124 get_root_bridge_busnr_callback
, res
);
125 if (ACPI_FAILURE(status
))
127 if (res
->start
== -1)
132 static u8 pci_osc_uuid_str
[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
134 static acpi_status
acpi_pci_run_osc(acpi_handle handle
,
135 const u32
*capbuf
, u32
*retval
)
137 struct acpi_osc_context context
= {
138 .uuid_str
= pci_osc_uuid_str
,
141 .cap
.pointer
= (void *)capbuf
,
145 status
= acpi_run_osc(handle
, &context
);
146 if (ACPI_SUCCESS(status
)) {
147 *retval
= *((u32
*)(context
.ret
.pointer
+ 8));
148 kfree(context
.ret
.pointer
);
153 static acpi_status
acpi_pci_query_osc(struct acpi_pci_root
*root
,
158 u32 result
, capbuf
[3];
160 support
&= OSC_PCI_SUPPORT_MASKS
;
161 support
|= root
->osc_support_set
;
163 capbuf
[OSC_QUERY_TYPE
] = OSC_QUERY_ENABLE
;
164 capbuf
[OSC_SUPPORT_TYPE
] = support
;
166 *control
&= OSC_PCI_CONTROL_MASKS
;
167 capbuf
[OSC_CONTROL_TYPE
] = *control
| root
->osc_control_set
;
169 /* Run _OSC query only with existing controls. */
170 capbuf
[OSC_CONTROL_TYPE
] = root
->osc_control_set
;
173 status
= acpi_pci_run_osc(root
->device
->handle
, capbuf
, &result
);
174 if (ACPI_SUCCESS(status
)) {
175 root
->osc_support_set
= support
;
182 static acpi_status
acpi_pci_osc_support(struct acpi_pci_root
*root
, u32 flags
)
187 status
= acpi_get_handle(root
->device
->handle
, "_OSC", &tmp
);
188 if (ACPI_FAILURE(status
))
190 mutex_lock(&osc_lock
);
191 status
= acpi_pci_query_osc(root
, flags
, NULL
);
192 mutex_unlock(&osc_lock
);
196 struct acpi_pci_root
*acpi_pci_find_root(acpi_handle handle
)
198 struct acpi_pci_root
*root
;
199 struct acpi_device
*device
;
201 if (acpi_bus_get_device(handle
, &device
) ||
202 acpi_match_device_ids(device
, root_device_ids
))
205 root
= acpi_driver_data(device
);
209 EXPORT_SYMBOL_GPL(acpi_pci_find_root
);
211 struct acpi_handle_node
{
212 struct list_head node
;
217 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
218 * @handle: the handle in question
220 * Given an ACPI CA handle, the desired PCI device is located in the
221 * list of PCI devices.
223 * If the device is found, its reference count is increased and this
224 * function returns a pointer to its data structure. The caller must
225 * decrement the reference count by calling pci_dev_put().
226 * If no device is found, %NULL is returned.
228 struct pci_dev
*acpi_get_pci_dev(acpi_handle handle
)
231 unsigned long long adr
;
234 struct pci_bus
*pbus
;
235 struct pci_dev
*pdev
= NULL
;
236 struct acpi_handle_node
*node
, *tmp
;
237 struct acpi_pci_root
*root
;
238 LIST_HEAD(device_list
);
241 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
244 while (!acpi_is_root_bridge(phandle
)) {
245 node
= kzalloc(sizeof(struct acpi_handle_node
), GFP_KERNEL
);
249 INIT_LIST_HEAD(&node
->node
);
250 node
->handle
= phandle
;
251 list_add(&node
->node
, &device_list
);
253 status
= acpi_get_parent(phandle
, &phandle
);
254 if (ACPI_FAILURE(status
))
258 root
= acpi_pci_find_root(phandle
);
265 * Now, walk back down the PCI device tree until we return to our
266 * original handle. Assumes that everything between the PCI root
267 * bridge and the device we're looking for must be a P2P bridge.
269 list_for_each_entry(node
, &device_list
, node
) {
270 acpi_handle hnd
= node
->handle
;
271 status
= acpi_evaluate_integer(hnd
, "_ADR", NULL
, &adr
);
272 if (ACPI_FAILURE(status
))
274 dev
= (adr
>> 16) & 0xffff;
277 pdev
= pci_get_slot(pbus
, PCI_DEVFN(dev
, fn
));
278 if (!pdev
|| hnd
== handle
)
281 pbus
= pdev
->subordinate
;
285 * This function may be called for a non-PCI device that has a
286 * PCI parent (eg. a disk under a PCI SATA controller). In that
287 * case pdev->subordinate will be NULL for the parent.
290 dev_dbg(&pdev
->dev
, "Not a PCI-to-PCI bridge\n");
296 list_for_each_entry_safe(node
, tmp
, &device_list
, node
)
301 EXPORT_SYMBOL_GPL(acpi_get_pci_dev
);
304 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
305 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
306 * @mask: Mask of _OSC bits to request control of, place to store control mask.
307 * @req: Mask of _OSC bits the control of is essential to the caller.
309 * Run _OSC query for @mask and if that is successful, compare the returned
310 * mask of control bits with @req. If all of the @req bits are set in the
311 * returned mask, run _OSC request for it.
313 * The variable at the @mask address may be modified regardless of whether or
314 * not the function returns success. On success it will contain the mask of
315 * _OSC bits the BIOS has granted control of, but its contents are meaningless
318 acpi_status
acpi_pci_osc_control_set(acpi_handle handle
, u32
*mask
, u32 req
)
320 struct acpi_pci_root
*root
;
326 return AE_BAD_PARAMETER
;
328 ctrl
= *mask
& OSC_PCI_CONTROL_MASKS
;
329 if ((ctrl
& req
) != req
)
332 root
= acpi_pci_find_root(handle
);
336 status
= acpi_get_handle(handle
, "_OSC", &tmp
);
337 if (ACPI_FAILURE(status
))
340 mutex_lock(&osc_lock
);
342 *mask
= ctrl
| root
->osc_control_set
;
343 /* No need to evaluate _OSC if the control was already granted. */
344 if ((root
->osc_control_set
& ctrl
) == ctrl
)
347 /* Need to check the available controls bits before requesting them. */
349 status
= acpi_pci_query_osc(root
, root
->osc_support_set
, mask
);
350 if (ACPI_FAILURE(status
))
357 if ((ctrl
& req
) != req
) {
362 capbuf
[OSC_QUERY_TYPE
] = 0;
363 capbuf
[OSC_SUPPORT_TYPE
] = root
->osc_support_set
;
364 capbuf
[OSC_CONTROL_TYPE
] = ctrl
;
365 status
= acpi_pci_run_osc(handle
, capbuf
, mask
);
366 if (ACPI_SUCCESS(status
))
367 root
->osc_control_set
= *mask
;
369 mutex_unlock(&osc_lock
);
372 EXPORT_SYMBOL(acpi_pci_osc_control_set
);
374 static int acpi_pci_root_add(struct acpi_device
*device
,
375 const struct acpi_device_id
*not_used
)
377 unsigned long long segment
, bus
;
380 struct acpi_pci_root
*root
;
381 u32 flags
, base_flags
;
382 acpi_handle handle
= device
->handle
;
383 bool no_aspm
= false, clear_aspm
= false;
385 root
= kzalloc(sizeof(struct acpi_pci_root
), GFP_KERNEL
);
390 status
= acpi_evaluate_integer(handle
, METHOD_NAME__SEG
, NULL
,
392 if (ACPI_FAILURE(status
) && status
!= AE_NOT_FOUND
) {
393 dev_err(&device
->dev
, "can't evaluate _SEG\n");
398 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
399 root
->secondary
.flags
= IORESOURCE_BUS
;
400 status
= try_get_root_bridge_busnr(handle
, &root
->secondary
);
401 if (ACPI_FAILURE(status
)) {
403 * We need both the start and end of the downstream bus range
404 * to interpret _CBA (MMCONFIG base address), so it really is
405 * supposed to be in _CRS. If we don't find it there, all we
406 * can do is assume [_BBN-0xFF] or [0-0xFF].
408 root
->secondary
.end
= 0xFF;
409 dev_warn(&device
->dev
,
410 FW_BUG
"no secondary bus range in _CRS\n");
411 status
= acpi_evaluate_integer(handle
, METHOD_NAME__BBN
,
413 if (ACPI_SUCCESS(status
))
414 root
->secondary
.start
= bus
;
415 else if (status
== AE_NOT_FOUND
)
416 root
->secondary
.start
= 0;
418 dev_err(&device
->dev
, "can't evaluate _BBN\n");
424 root
->device
= device
;
425 root
->segment
= segment
& 0xFFFF;
426 strcpy(acpi_device_name(device
), ACPI_PCI_ROOT_DEVICE_NAME
);
427 strcpy(acpi_device_class(device
), ACPI_PCI_ROOT_CLASS
);
428 device
->driver_data
= root
;
430 pr_info(PREFIX
"%s [%s] (domain %04x %pR)\n",
431 acpi_device_name(device
), acpi_device_bid(device
),
432 root
->segment
, &root
->secondary
);
434 root
->mcfg_addr
= acpi_pci_root_get_mcfg_addr(handle
);
437 * All supported architectures that use ACPI have support for
438 * PCI domains, so we indicate this in _OSC support capabilities.
440 flags
= base_flags
= OSC_PCI_SEGMENT_GROUPS_SUPPORT
;
441 acpi_pci_osc_support(root
, flags
);
443 if (pci_ext_cfg_avail())
444 flags
|= OSC_EXT_PCI_CONFIG_SUPPORT
;
445 if (pcie_aspm_support_enabled()) {
446 flags
|= OSC_ACTIVE_STATE_PWR_SUPPORT
|
447 OSC_CLOCK_PWR_CAPABILITY_SUPPORT
;
449 if (pci_msi_enabled())
450 flags
|= OSC_MSI_SUPPORT
;
451 if (flags
!= base_flags
) {
452 status
= acpi_pci_osc_support(root
, flags
);
453 if (ACPI_FAILURE(status
)) {
454 dev_info(&device
->dev
, "ACPI _OSC support "
455 "notification failed, disabling PCIe ASPM\n");
461 if (!pcie_ports_disabled
462 && (flags
& ACPI_PCIE_REQ_SUPPORT
) == ACPI_PCIE_REQ_SUPPORT
) {
463 flags
= OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
464 | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
465 | OSC_PCI_EXPRESS_PME_CONTROL
;
467 if (pci_aer_available()) {
468 if (aer_acpi_firmware_first())
469 dev_dbg(&device
->dev
,
470 "PCIe errors handled by BIOS.\n");
472 flags
|= OSC_PCI_EXPRESS_AER_CONTROL
;
475 dev_info(&device
->dev
,
476 "Requesting ACPI _OSC control (0x%02x)\n", flags
);
478 status
= acpi_pci_osc_control_set(handle
, &flags
,
479 OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
);
480 if (ACPI_SUCCESS(status
)) {
481 dev_info(&device
->dev
,
482 "ACPI _OSC control (0x%02x) granted\n", flags
);
483 if (acpi_gbl_FADT
.boot_flags
& ACPI_FADT_NO_ASPM
) {
485 * We have ASPM control, but the FADT indicates
486 * that it's unsupported. Clear it.
491 dev_info(&device
->dev
,
492 "ACPI _OSC request failed (%s), "
493 "returned control mask: 0x%02x\n",
494 acpi_format_exception(status
), flags
);
495 dev_info(&device
->dev
,
496 "ACPI _OSC control for PCIe not granted, disabling ASPM\n");
498 * We want to disable ASPM here, but aspm_disabled
499 * needs to remain in its state from boot so that we
500 * properly handle PCIe 1.1 devices. So we set this
501 * flag here, to defer the action until after the ACPI
507 dev_info(&device
->dev
,
508 "Unable to request _OSC control "
509 "(_OSC support mask: 0x%02x)\n", flags
);
513 * TBD: Need PCI interface for enumeration/configuration of roots.
517 * Scan the Root Bridge
518 * --------------------
519 * Must do this prior to any attempt to bind the root device, as the
520 * PCI namespace does not get created until this call is made (and
521 * thus the root bridge's pci_dev does not exist).
523 root
->bus
= pci_acpi_scan_root(root
);
525 dev_err(&device
->dev
,
526 "Bus %04x:%02x not present in PCI namespace\n",
527 root
->segment
, (unsigned int)root
->secondary
.start
);
533 dev_info(&device
->dev
, "Disabling ASPM (FADT indicates it is unsupported)\n");
534 pcie_clear_aspm(root
->bus
);
539 pci_acpi_add_bus_pm_notifier(device
, root
->bus
);
540 if (device
->wakeup
.flags
.run_wake
)
541 device_set_run_wake(root
->bus
->bridge
, true);
543 if (system_state
!= SYSTEM_BOOTING
) {
544 pcibios_resource_survey_bus(root
->bus
);
545 pci_assign_unassigned_root_bus_resources(root
->bus
);
548 pci_bus_add_devices(root
->bus
);
556 static void acpi_pci_root_remove(struct acpi_device
*device
)
558 struct acpi_pci_root
*root
= acpi_driver_data(device
);
560 pci_stop_root_bus(root
->bus
);
562 device_set_run_wake(root
->bus
->bridge
, false);
563 pci_acpi_remove_bus_pm_notifier(device
);
565 pci_remove_root_bus(root
->bus
);
570 void __init
acpi_pci_root_init(void)
574 if (!acpi_pci_disabled
) {
575 pci_acpi_crs_quirks();
576 acpi_scan_add_handler(&pci_root_handler
);
579 /* Support root bridge hotplug */
581 static void handle_root_bridge_insertion(acpi_handle handle
)
583 struct acpi_device
*device
;
585 if (!acpi_bus_get_device(handle
, &device
)) {
586 dev_printk(KERN_DEBUG
, &device
->dev
,
587 "acpi device already exists; ignoring notify\n");
591 if (acpi_bus_scan(handle
))
592 acpi_handle_err(handle
, "cannot add bridge to acpi list\n");
595 static void hotplug_event_root(void *data
, u32 type
)
597 acpi_handle handle
= data
;
598 struct acpi_pci_root
*root
;
600 acpi_scan_lock_acquire();
602 root
= acpi_pci_find_root(handle
);
605 case ACPI_NOTIFY_BUS_CHECK
:
607 acpi_handle_printk(KERN_DEBUG
, handle
,
608 "Bus check notify on %s\n", __func__
);
610 acpiphp_check_host_bridge(handle
);
612 handle_root_bridge_insertion(handle
);
616 case ACPI_NOTIFY_DEVICE_CHECK
:
618 acpi_handle_printk(KERN_DEBUG
, handle
,
619 "Device check notify on %s\n", __func__
);
621 handle_root_bridge_insertion(handle
);
624 case ACPI_NOTIFY_EJECT_REQUEST
:
625 /* request device eject */
626 acpi_handle_printk(KERN_DEBUG
, handle
,
627 "Device eject notify on %s\n", __func__
);
631 get_device(&root
->device
->dev
);
633 acpi_scan_lock_release();
635 acpi_bus_device_eject(root
->device
, ACPI_NOTIFY_EJECT_REQUEST
);
638 acpi_handle_warn(handle
,
639 "notify_handler: unknown event type 0x%x\n",
644 acpi_scan_lock_release();
647 static void handle_hotplug_event_root(acpi_handle handle
, u32 type
,
650 acpi_hotplug_execute(hotplug_event_root
, handle
, type
);
653 static acpi_status __init
654 find_root_bridges(acpi_handle handle
, u32 lvl
, void *context
, void **rv
)
657 int *count
= (int *)context
;
659 if (!acpi_is_root_bridge(handle
))
664 status
= acpi_install_notify_handler(handle
, ACPI_SYSTEM_NOTIFY
,
665 handle_hotplug_event_root
, NULL
);
666 if (ACPI_FAILURE(status
))
667 acpi_handle_printk(KERN_DEBUG
, handle
,
668 "notify handler is not installed, exit status: %u\n",
669 (unsigned int)status
);
671 acpi_handle_printk(KERN_DEBUG
, handle
,
672 "notify handler is installed\n");
677 void __init
acpi_pci_root_hp_init(void)
681 acpi_walk_namespace(ACPI_TYPE_DEVICE
, ACPI_ROOT_OBJECT
,
682 ACPI_UINT32_MAX
, find_root_bridges
, NULL
, &num
, NULL
);
684 printk(KERN_DEBUG
"Found %d acpi root devices\n", num
);