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pci_root.c
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pci_root.c
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
*
* Copyright (C) 2001, 2002 Andy Grover <[email protected]>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
*/
#define pr_fmt(fmt) "ACPI: " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/pci.h>
#include <linux/pci-acpi.h>
#include <linux/dmar.h>
#include <linux/acpi.h>
#include <linux/slab.h>
#include <linux/dmi.h>
#include <linux/platform_data/x86/apple.h>
#include "internal.h"
#define ACPI_PCI_ROOT_CLASS "pci_bridge"
#define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
static int acpi_pci_root_add(struct acpi_device *device,
const struct acpi_device_id *not_used);
static void acpi_pci_root_remove(struct acpi_device *device);
static int acpi_pci_root_scan_dependent(struct acpi_device *adev)
{
acpiphp_check_host_bridge(adev);
return 0;
}
#define ACPI_PCIE_REQ_SUPPORT (OSC_PCI_EXT_CONFIG_SUPPORT \
| OSC_PCI_ASPM_SUPPORT \
| OSC_PCI_CLOCK_PM_SUPPORT \
| OSC_PCI_MSI_SUPPORT)
static const struct acpi_device_id root_device_ids[] = {
{"PNP0A03", 0},
{"", 0},
};
static struct acpi_scan_handler pci_root_handler = {
.ids = root_device_ids,
.attach = acpi_pci_root_add,
.detach = acpi_pci_root_remove,
.hotplug = {
.enabled = true,
.scan_dependent = acpi_pci_root_scan_dependent,
},
};
/**
* acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
* @handle: the ACPI CA node in question.
*
* Note: we could make this API take a struct acpi_device * instead, but
* for now, it's more convenient to operate on an acpi_handle.
*/
int acpi_is_root_bridge(acpi_handle handle)
{
struct acpi_device *device = acpi_fetch_acpi_dev(handle);
int ret;
if (!device)
return 0;
ret = acpi_match_device_ids(device, root_device_ids);
if (ret)
return 0;
else
return 1;
}
EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
static acpi_status
get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
{
struct resource *res = data;
struct acpi_resource_address64 address;
acpi_status status;
status = acpi_resource_to_address64(resource, &address);
if (ACPI_FAILURE(status))
return AE_OK;
if ((address.address.address_length > 0) &&
(address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
res->start = address.address.minimum;
res->end = address.address.minimum + address.address.address_length - 1;
}
return AE_OK;
}
static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
struct resource *res)
{
acpi_status status;
res->start = -1;
status =
acpi_walk_resources(handle, METHOD_NAME__CRS,
get_root_bridge_busnr_callback, res);
if (ACPI_FAILURE(status))
return status;
if (res->start == -1)
return AE_ERROR;
return AE_OK;
}
struct pci_osc_bit_struct {
u32 bit;
char *desc;
};
static struct pci_osc_bit_struct pci_osc_support_bit[] = {
{ OSC_PCI_EXT_CONFIG_SUPPORT, "ExtendedConfig" },
{ OSC_PCI_ASPM_SUPPORT, "ASPM" },
{ OSC_PCI_CLOCK_PM_SUPPORT, "ClockPM" },
{ OSC_PCI_SEGMENT_GROUPS_SUPPORT, "Segments" },
{ OSC_PCI_MSI_SUPPORT, "MSI" },
{ OSC_PCI_EDR_SUPPORT, "EDR" },
{ OSC_PCI_HPX_TYPE_3_SUPPORT, "HPX-Type3" },
};
static struct pci_osc_bit_struct pci_osc_control_bit[] = {
{ OSC_PCI_EXPRESS_NATIVE_HP_CONTROL, "PCIeHotplug" },
{ OSC_PCI_SHPC_NATIVE_HP_CONTROL, "SHPCHotplug" },
{ OSC_PCI_EXPRESS_PME_CONTROL, "PME" },
{ OSC_PCI_EXPRESS_AER_CONTROL, "AER" },
{ OSC_PCI_EXPRESS_CAPABILITY_CONTROL, "PCIeCapability" },
{ OSC_PCI_EXPRESS_LTR_CONTROL, "LTR" },
{ OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
};
static struct pci_osc_bit_struct cxl_osc_support_bit[] = {
{ OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT, "CXL11PortRegAccess" },
{ OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT, "CXL20PortDevRegAccess" },
{ OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT, "CXLProtocolErrorReporting" },
{ OSC_CXL_NATIVE_HP_SUPPORT, "CXLNativeHotPlug" },
};
static struct pci_osc_bit_struct cxl_osc_control_bit[] = {
{ OSC_CXL_ERROR_REPORTING_CONTROL, "CXLMemErrorReporting" },
};
static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
struct pci_osc_bit_struct *table, int size)
{
char buf[80];
int i, len = 0;
struct pci_osc_bit_struct *entry;
buf[0] = '\0';
for (i = 0, entry = table; i < size; i++, entry++)
if (word & entry->bit)
len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
len ? " " : "", entry->desc);
dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);
}
static void decode_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
{
decode_osc_bits(root, msg, word, pci_osc_support_bit,
ARRAY_SIZE(pci_osc_support_bit));
}
static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
{
decode_osc_bits(root, msg, word, pci_osc_control_bit,
ARRAY_SIZE(pci_osc_control_bit));
}
static void decode_cxl_osc_support(struct acpi_pci_root *root, char *msg, u32 word)
{
decode_osc_bits(root, msg, word, cxl_osc_support_bit,
ARRAY_SIZE(cxl_osc_support_bit));
}
static void decode_cxl_osc_control(struct acpi_pci_root *root, char *msg, u32 word)
{
decode_osc_bits(root, msg, word, cxl_osc_control_bit,
ARRAY_SIZE(cxl_osc_control_bit));
}
static inline bool is_pcie(struct acpi_pci_root *root)
{
return root->bridge_type == ACPI_BRIDGE_TYPE_PCIE;
}
static inline bool is_cxl(struct acpi_pci_root *root)
{
return root->bridge_type == ACPI_BRIDGE_TYPE_CXL;
}
static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
static u8 cxl_osc_uuid_str[] = "68F2D50B-C469-4d8A-BD3D-941A103FD3FC";
static char *to_uuid(struct acpi_pci_root *root)
{
if (is_cxl(root))
return cxl_osc_uuid_str;
return pci_osc_uuid_str;
}
static int cap_length(struct acpi_pci_root *root)
{
if (is_cxl(root))
return sizeof(u32) * OSC_CXL_CAPABILITY_DWORDS;
return sizeof(u32) * OSC_PCI_CAPABILITY_DWORDS;
}
static acpi_status acpi_pci_run_osc(struct acpi_pci_root *root,
const u32 *capbuf, u32 *pci_control,
u32 *cxl_control)
{
struct acpi_osc_context context = {
.uuid_str = to_uuid(root),
.rev = 1,
.cap.length = cap_length(root),
.cap.pointer = (void *)capbuf,
};
acpi_status status;
status = acpi_run_osc(root->device->handle, &context);
if (ACPI_SUCCESS(status)) {
*pci_control = acpi_osc_ctx_get_pci_control(&context);
if (is_cxl(root))
*cxl_control = acpi_osc_ctx_get_cxl_control(&context);
kfree(context.ret.pointer);
}
return status;
}
static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 support,
u32 *control, u32 cxl_support,
u32 *cxl_control)
{
acpi_status status;
u32 pci_result, cxl_result, capbuf[OSC_CXL_CAPABILITY_DWORDS];
support |= root->osc_support_set;
capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
capbuf[OSC_SUPPORT_DWORD] = support;
capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
if (is_cxl(root)) {
cxl_support |= root->osc_ext_support_set;
capbuf[OSC_EXT_SUPPORT_DWORD] = cxl_support;
capbuf[OSC_EXT_CONTROL_DWORD] = *cxl_control | root->osc_ext_control_set;
}
retry:
status = acpi_pci_run_osc(root, capbuf, &pci_result, &cxl_result);
if (ACPI_SUCCESS(status)) {
root->osc_support_set = support;
*control = pci_result;
if (is_cxl(root)) {
root->osc_ext_support_set = cxl_support;
*cxl_control = cxl_result;
}
} else if (is_cxl(root)) {
/*
* CXL _OSC is optional on CXL 1.1 hosts. Fall back to PCIe _OSC
* upon any failure using CXL _OSC.
*/
root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
goto retry;
}
return status;
}
struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
{
struct acpi_device *device = acpi_fetch_acpi_dev(handle);
struct acpi_pci_root *root;
if (!device || acpi_match_device_ids(device, root_device_ids))
return NULL;
root = acpi_driver_data(device);
return root;
}
EXPORT_SYMBOL_GPL(acpi_pci_find_root);
struct acpi_handle_node {
struct list_head node;
acpi_handle handle;
};
/**
* acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
* @handle: the handle in question
*
* Given an ACPI CA handle, the desired PCI device is located in the
* list of PCI devices.
*
* If the device is found, its reference count is increased and this
* function returns a pointer to its data structure. The caller must
* decrement the reference count by calling pci_dev_put().
* If no device is found, %NULL is returned.
*/
struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
{
struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
struct acpi_device_physical_node *pn;
struct pci_dev *pci_dev = NULL;
if (!adev)
return NULL;
mutex_lock(&adev->physical_node_lock);
list_for_each_entry(pn, &adev->physical_node_list, node) {
if (dev_is_pci(pn->dev)) {
get_device(pn->dev);
pci_dev = to_pci_dev(pn->dev);
break;
}
}
mutex_unlock(&adev->physical_node_lock);
return pci_dev;
}
EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
/**
* acpi_pci_osc_control_set - Request control of PCI root _OSC features.
* @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
* @mask: Mask of _OSC bits to request control of, place to store control mask.
* @support: _OSC supported capability.
* @cxl_mask: Mask of CXL _OSC control bits, place to store control mask.
* @cxl_support: CXL _OSC supported capability.
*
* Run _OSC query for @mask and if that is successful, compare the returned
* mask of control bits with @req. If all of the @req bits are set in the
* returned mask, run _OSC request for it.
*
* The variable at the @mask address may be modified regardless of whether or
* not the function returns success. On success it will contain the mask of
* _OSC bits the BIOS has granted control of, but its contents are meaningless
* on failure.
**/
static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask,
u32 support, u32 *cxl_mask,
u32 cxl_support)
{
u32 req = OSC_PCI_EXPRESS_CAPABILITY_CONTROL;
struct acpi_pci_root *root;
acpi_status status;
u32 ctrl, cxl_ctrl = 0, capbuf[OSC_CXL_CAPABILITY_DWORDS];
if (!mask)
return AE_BAD_PARAMETER;
root = acpi_pci_find_root(handle);
if (!root)
return AE_NOT_EXIST;
ctrl = *mask;
*mask |= root->osc_control_set;
if (is_cxl(root)) {
cxl_ctrl = *cxl_mask;
*cxl_mask |= root->osc_ext_control_set;
}
/* Need to check the available controls bits before requesting them. */
do {
u32 pci_missing = 0, cxl_missing = 0;
status = acpi_pci_query_osc(root, support, mask, cxl_support,
cxl_mask);
if (ACPI_FAILURE(status))
return status;
if (is_cxl(root)) {
if (ctrl == *mask && cxl_ctrl == *cxl_mask)
break;
pci_missing = ctrl & ~(*mask);
cxl_missing = cxl_ctrl & ~(*cxl_mask);
} else {
if (ctrl == *mask)
break;
pci_missing = ctrl & ~(*mask);
}
if (pci_missing)
decode_osc_control(root, "platform does not support",
pci_missing);
if (cxl_missing)
decode_cxl_osc_control(root, "CXL platform does not support",
cxl_missing);
ctrl = *mask;
cxl_ctrl = *cxl_mask;
} while (*mask || *cxl_mask);
/* No need to request _OSC if the control was already granted. */
if ((root->osc_control_set & ctrl) == ctrl &&
(root->osc_ext_control_set & cxl_ctrl) == cxl_ctrl)
return AE_OK;
if ((ctrl & req) != req) {
decode_osc_control(root, "not requesting control; platform does not support",
req & ~(ctrl));
return AE_SUPPORT;
}
capbuf[OSC_QUERY_DWORD] = 0;
capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set;
capbuf[OSC_CONTROL_DWORD] = ctrl;
if (is_cxl(root)) {
capbuf[OSC_EXT_SUPPORT_DWORD] = root->osc_ext_support_set;
capbuf[OSC_EXT_CONTROL_DWORD] = cxl_ctrl;
}
status = acpi_pci_run_osc(root, capbuf, mask, cxl_mask);
if (ACPI_FAILURE(status))
return status;
root->osc_control_set = *mask;
root->osc_ext_control_set = *cxl_mask;
return AE_OK;
}
static u32 calculate_support(void)
{
u32 support;
/*
* All supported architectures that use ACPI have support for
* PCI domains, so we indicate this in _OSC support capabilities.
*/
support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
if (pci_ext_cfg_avail())
support |= OSC_PCI_EXT_CONFIG_SUPPORT;
if (pcie_aspm_support_enabled())
support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
if (pci_msi_enabled())
support |= OSC_PCI_MSI_SUPPORT;
if (IS_ENABLED(CONFIG_PCIE_EDR))
support |= OSC_PCI_EDR_SUPPORT;
return support;
}
/*
* Background on hotplug support, and making it depend on only
* CONFIG_HOTPLUG_PCI_PCIE vs. also considering CONFIG_MEMORY_HOTPLUG:
*
* CONFIG_ACPI_HOTPLUG_MEMORY does depend on CONFIG_MEMORY_HOTPLUG, but
* there is no existing _OSC for memory hotplug support. The reason is that
* ACPI memory hotplug requires the OS to acknowledge / coordinate with
* memory plug events via a scan handler. On the CXL side the equivalent
* would be if Linux supported the Mechanical Retention Lock [1], or
* otherwise had some coordination for the driver of a PCI device
* undergoing hotplug to be consulted on whether the hotplug should
* proceed or not.
*
* The concern is that if Linux says no to supporting CXL hotplug then
* the BIOS may say no to giving the OS hotplug control of any other PCIe
* device. So the question here is not whether hotplug is enabled, it's
* whether it is handled natively by the at all OS, and if
* CONFIG_HOTPLUG_PCI_PCIE is enabled then the answer is "yes".
*
* Otherwise, the plan for CXL coordinated remove, since the kernel does
* not support blocking hotplug, is to require the memory device to be
* disabled before hotplug is attempted. When CONFIG_MEMORY_HOTPLUG is
* disabled that step will fail and the remove attempt cancelled by the
* user. If that is not honored and the card is removed anyway then it
* does not matter if CONFIG_MEMORY_HOTPLUG is enabled or not, it will
* cause a crash and other badness.
*
* Therefore, just say yes to CXL hotplug and require removal to
* be coordinated by userspace unless and until the kernel grows better
* mechanisms for doing "managed" removal of devices in consultation with
* the driver.
*
* [1]: https://lore.kernel.org/all/[email protected]/
*/
static u32 calculate_cxl_support(void)
{
u32 support;
support = OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT;
support |= OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT;
if (pci_aer_available())
support |= OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT;
if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
support |= OSC_CXL_NATIVE_HP_SUPPORT;
return support;
}
static u32 calculate_control(void)
{
u32 control;
control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
| OSC_PCI_EXPRESS_PME_CONTROL;
if (IS_ENABLED(CONFIG_PCIEASPM))
control |= OSC_PCI_EXPRESS_LTR_CONTROL;
if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
if (pci_aer_available())
control |= OSC_PCI_EXPRESS_AER_CONTROL;
/*
* Per the Downstream Port Containment Related Enhancements ECN to
* the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
* OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
* and EDR.
*/
if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
control |= OSC_PCI_EXPRESS_DPC_CONTROL;
return control;
}
static u32 calculate_cxl_control(void)
{
u32 control = 0;
if (IS_ENABLED(CONFIG_MEMORY_FAILURE))
control |= OSC_CXL_ERROR_REPORTING_CONTROL;
return control;
}
static bool os_control_query_checks(struct acpi_pci_root *root, u32 support)
{
struct acpi_device *device = root->device;
if (pcie_ports_disabled) {
dev_info(&device->dev, "PCIe port services disabled; not requesting _OSC control\n");
return false;
}
if ((support & ACPI_PCIE_REQ_SUPPORT) != ACPI_PCIE_REQ_SUPPORT) {
decode_osc_support(root, "not requesting OS control; OS requires",
ACPI_PCIE_REQ_SUPPORT);
return false;
}
return true;
}
static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
{
u32 support, control = 0, requested = 0;
u32 cxl_support = 0, cxl_control = 0, cxl_requested = 0;
acpi_status status;
struct acpi_device *device = root->device;
acpi_handle handle = device->handle;
/*
* Apple always return failure on _OSC calls when _OSI("Darwin") has
* been called successfully. We know the feature set supported by the
* platform, so avoid calling _OSC at all
*/
if (x86_apple_machine) {
root->osc_control_set = ~OSC_PCI_EXPRESS_PME_CONTROL;
decode_osc_control(root, "OS assumes control of",
root->osc_control_set);
return;
}
support = calculate_support();
decode_osc_support(root, "OS supports", support);
if (os_control_query_checks(root, support))
requested = control = calculate_control();
if (is_cxl(root)) {
cxl_support = calculate_cxl_support();
decode_cxl_osc_support(root, "OS supports", cxl_support);
cxl_requested = cxl_control = calculate_cxl_control();
}
status = acpi_pci_osc_control_set(handle, &control, support,
&cxl_control, cxl_support);
if (ACPI_SUCCESS(status)) {
if (control)
decode_osc_control(root, "OS now controls", control);
if (cxl_control)
decode_cxl_osc_control(root, "OS now controls",
cxl_control);
if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
/*
* We have ASPM control, but the FADT indicates that
* it's unsupported. Leave existing configuration
* intact and prevent the OS from touching it.
*/
dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
*no_aspm = 1;
}
} else {
/*
* We want to disable ASPM here, but aspm_disabled
* needs to remain in its state from boot so that we
* properly handle PCIe 1.1 devices. So we set this
* flag here, to defer the action until after the ACPI
* root scan.
*/
*no_aspm = 1;
/* _OSC is optional for PCI host bridges */
if (status == AE_NOT_FOUND && !is_pcie(root))
return;
if (control) {
decode_osc_control(root, "OS requested", requested);
decode_osc_control(root, "platform willing to grant", control);
}
if (cxl_control) {
decode_cxl_osc_control(root, "OS requested", cxl_requested);
decode_cxl_osc_control(root, "platform willing to grant",
cxl_control);
}
dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
acpi_format_exception(status));
}
}
static int acpi_pci_root_add(struct acpi_device *device,
const struct acpi_device_id *not_used)
{
unsigned long long segment, bus;
acpi_status status;
int result;
struct acpi_pci_root *root;
acpi_handle handle = device->handle;
int no_aspm = 0;
bool hotadd = system_state == SYSTEM_RUNNING;
const char *acpi_hid;
root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
if (!root)
return -ENOMEM;
segment = 0;
status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL,
&segment);
if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
dev_err(&device->dev, "can't evaluate _SEG\n");
result = -ENODEV;
goto end;
}
/* Check _CRS first, then _BBN. If no _BBN, default to zero. */
root->secondary.flags = IORESOURCE_BUS;
status = try_get_root_bridge_busnr(handle, &root->secondary);
if (ACPI_FAILURE(status)) {
/*
* We need both the start and end of the downstream bus range
* to interpret _CBA (MMCONFIG base address), so it really is
* supposed to be in _CRS. If we don't find it there, all we
* can do is assume [_BBN-0xFF] or [0-0xFF].
*/
root->secondary.end = 0xFF;
dev_warn(&device->dev,
FW_BUG "no secondary bus range in _CRS\n");
status = acpi_evaluate_integer(handle, METHOD_NAME__BBN,
NULL, &bus);
if (ACPI_SUCCESS(status))
root->secondary.start = bus;
else if (status == AE_NOT_FOUND)
root->secondary.start = 0;
else {
dev_err(&device->dev, "can't evaluate _BBN\n");
result = -ENODEV;
goto end;
}
}
root->device = device;
root->segment = segment & 0xFFFF;
strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
device->driver_data = root;
if (hotadd && dmar_device_add(handle)) {
result = -ENXIO;
goto end;
}
pr_info("%s [%s] (domain %04x %pR)\n",
acpi_device_name(device), acpi_device_bid(device),
root->segment, &root->secondary);
root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
acpi_hid = acpi_device_hid(root->device);
if (strcmp(acpi_hid, "PNP0A08") == 0)
root->bridge_type = ACPI_BRIDGE_TYPE_PCIE;
else if (strcmp(acpi_hid, "ACPI0016") == 0)
root->bridge_type = ACPI_BRIDGE_TYPE_CXL;
else
dev_dbg(&device->dev, "Assuming non-PCIe host bridge\n");
negotiate_os_control(root, &no_aspm);
/*
* TBD: Need PCI interface for enumeration/configuration of roots.
*/
/*
* Scan the Root Bridge
* --------------------
* Must do this prior to any attempt to bind the root device, as the
* PCI namespace does not get created until this call is made (and
* thus the root bridge's pci_dev does not exist).
*/
root->bus = pci_acpi_scan_root(root);
if (!root->bus) {
dev_err(&device->dev,
"Bus %04x:%02x not present in PCI namespace\n",
root->segment, (unsigned int)root->secondary.start);
device->driver_data = NULL;
result = -ENODEV;
goto remove_dmar;
}
if (no_aspm)
pcie_no_aspm();
pci_acpi_add_bus_pm_notifier(device);
device_set_wakeup_capable(root->bus->bridge, device->wakeup.flags.valid);
if (hotadd) {
pcibios_resource_survey_bus(root->bus);
pci_assign_unassigned_root_bus_resources(root->bus);
/*
* This is only called for the hotadd case. For the boot-time
* case, we need to wait until after PCI initialization in
* order to deal with IOAPICs mapped in on a PCI BAR.
*
* This is currently x86-specific, because acpi_ioapic_add()
* is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC.
* And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC
* (see drivers/acpi/Kconfig).
*/
acpi_ioapic_add(root->device->handle);
}
pci_lock_rescan_remove();
pci_bus_add_devices(root->bus);
pci_unlock_rescan_remove();
return 1;
remove_dmar:
if (hotadd)
dmar_device_remove(handle);
end:
kfree(root);
return result;
}
static void acpi_pci_root_remove(struct acpi_device *device)
{
struct acpi_pci_root *root = acpi_driver_data(device);
pci_lock_rescan_remove();
pci_stop_root_bus(root->bus);
pci_ioapic_remove(root);
device_set_wakeup_capable(root->bus->bridge, false);
pci_acpi_remove_bus_pm_notifier(device);
pci_remove_root_bus(root->bus);
WARN_ON(acpi_ioapic_remove(root));
dmar_device_remove(device->handle);
pci_unlock_rescan_remove();
kfree(root);
}
/*
* Following code to support acpi_pci_root_create() is copied from
* arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
* and ARM64.
*/
static void acpi_pci_root_validate_resources(struct device *dev,
struct list_head *resources,
unsigned long type)
{
LIST_HEAD(list);
struct resource *res1, *res2, *root = NULL;
struct resource_entry *tmp, *entry, *entry2;
BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
list_splice_init(resources, &list);
resource_list_for_each_entry_safe(entry, tmp, &list) {
bool free = false;
resource_size_t end;
res1 = entry->res;
if (!(res1->flags & type))
goto next;
/* Exclude non-addressable range or non-addressable portion */
end = min(res1->end, root->end);
if (end <= res1->start) {
dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
res1);
free = true;
goto next;
} else if (res1->end != end) {
dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
res1, (unsigned long long)end + 1,
(unsigned long long)res1->end);
res1->end = end;
}
resource_list_for_each_entry(entry2, resources) {
res2 = entry2->res;
if (!(res2->flags & type))
continue;
/*
* I don't like throwing away windows because then
* our resources no longer match the ACPI _CRS, but
* the kernel resource tree doesn't allow overlaps.
*/
if (resource_union(res1, res2, res2)) {
dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
res2, res1);
free = true;
goto next;
}
}
next:
resource_list_del(entry);
if (free)
resource_list_free_entry(entry);
else
resource_list_add_tail(entry, resources);
}
}
static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
struct resource_entry *entry)
{
#ifdef PCI_IOBASE
struct resource *res = entry->res;
resource_size_t cpu_addr = res->start;
resource_size_t pci_addr = cpu_addr - entry->offset;
resource_size_t length = resource_size(res);
unsigned long port;
if (pci_register_io_range(fwnode, cpu_addr, length))
goto err;
port = pci_address_to_pio(cpu_addr);
if (port == (unsigned long)-1)
goto err;
res->start = port;
res->end = port + length - 1;
entry->offset = port - pci_addr;
if (pci_remap_iospace(res, cpu_addr) < 0)
goto err;
pr_info("Remapped I/O %pa to %pR\n", &cpu_addr, res);
return;
err:
res->flags |= IORESOURCE_DISABLED;
#endif
}
int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
{
int ret;
struct list_head *list = &info->resources;
struct acpi_device *device = info->bridge;
struct resource_entry *entry, *tmp;
unsigned long flags;
flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
ret = acpi_dev_get_resources(device, list,
acpi_dev_filter_resource_type_cb,
(void *)flags);
if (ret < 0)
dev_warn(&device->dev,
"failed to parse _CRS method, error code %d\n", ret);
else if (ret == 0)
dev_dbg(&device->dev,
"no IO and memory resources present in _CRS\n");
else {
resource_list_for_each_entry_safe(entry, tmp, list) {
if (entry->res->flags & IORESOURCE_IO)
acpi_pci_root_remap_iospace(&device->fwnode,
entry);
if (entry->res->flags & IORESOURCE_DISABLED)
resource_list_destroy_entry(entry);
else
entry->res->name = info->name;
}
acpi_pci_root_validate_resources(&device->dev, list,
IORESOURCE_MEM);
acpi_pci_root_validate_resources(&device->dev, list,
IORESOURCE_IO);
}
return ret;
}
static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
{
struct resource_entry *entry, *tmp;
struct resource *res, *conflict, *root = NULL;
resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
res = entry->res;
if (res->flags & IORESOURCE_MEM)
root = &iomem_resource;
else if (res->flags & IORESOURCE_IO)
root = &ioport_resource;
else
continue;
/*
* Some legacy x86 host bridge drivers use iomem_resource and
* ioport_resource as default resource pool, skip it.
*/
if (res == root)
continue;
conflict = insert_resource_conflict(root, res);
if (conflict) {
dev_info(&info->bridge->dev,
"ignoring host bridge window %pR (conflicts with %s %pR)\n",
res, conflict->name, conflict);
resource_list_destroy_entry(entry);
}
}
}
static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
{
struct resource *res;
struct resource_entry *entry, *tmp;
if (!info)
return;
resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
res = entry->res;
if (res->parent &&
(res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
release_resource(res);
resource_list_destroy_entry(entry);
}
info->ops->release_info(info);
}
static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
{
struct resource *res;
struct resource_entry *entry;
resource_list_for_each_entry(entry, &bridge->windows) {
res = entry->res;
if (res->flags & IORESOURCE_IO)
pci_unmap_iospace(res);
if (res->parent &&
(res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
release_resource(res);
}
__acpi_pci_root_release_info(bridge->release_data);
}