kernel_optimize_test/drivers/acpi/property.c
Mika Westerberg 617654aae5 PCI / ACPI: Identify untrusted PCI devices
A malicious PCI device may use DMA to attack the system. An external
Thunderbolt port is a convenient point to attach such a device. The OS
may use IOMMU to defend against DMA attacks.

Some BIOSes mark these externally facing root ports with this
ACPI _DSD [1]:

  Name (_DSD, Package () {
      ToUUID ("efcc06cc-73ac-4bc3-bff0-76143807c389"),
      Package () {
          Package () {"ExternalFacingPort", 1},
	  Package () {"UID", 0 }
      }
  })

If we find such a root port, mark it and all its children as untrusted.
The rest of the OS may use this information to enable DMA protection
against malicious devices. For instance the device may be put behind an
IOMMU to keep it from accessing memory outside of what the driver has
allocated for it.

While at it, add a comment on top of prp_guids array explaining the
possible caveat resulting when these GUIDs are treated equivalent.

[1] https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-externally-exposed-pcie-root-ports

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2018-12-05 12:01:55 +03:00

1360 lines
35 KiB
C

/*
* ACPI device specific properties support.
*
* Copyright (C) 2014, Intel Corporation
* All rights reserved.
*
* Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
* Darren Hart <dvhart@linux.intel.com>
* Rafael J. Wysocki <rafael.j.wysocki@intel.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/export.h>
#include "internal.h"
static int acpi_data_get_property_array(const struct acpi_device_data *data,
const char *name,
acpi_object_type type,
const union acpi_object **obj);
/*
* The GUIDs here are made equivalent to each other in order to avoid extra
* complexity in the properties handling code, with the caveat that the
* kernel will accept certain combinations of GUID and properties that are
* not defined without a warning. For instance if any of the properties
* from different GUID appear in a property list of another, it will be
* accepted by the kernel. Firmware validation tools should catch these.
*/
static const guid_t prp_guids[] = {
/* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c,
0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01),
/* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */
GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3,
0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4),
/* External facing port GUID: efcc06cc-73ac-4bc3-bff0-76143807c389 */
GUID_INIT(0xefcc06cc, 0x73ac, 0x4bc3,
0xbf, 0xf0, 0x76, 0x14, 0x38, 0x07, 0xc3, 0x89),
};
static const guid_t ads_guid =
GUID_INIT(0xdbb8e3e6, 0x5886, 0x4ba6,
0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b);
static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
const union acpi_object *desc,
struct acpi_device_data *data,
struct fwnode_handle *parent);
static bool acpi_extract_properties(const union acpi_object *desc,
struct acpi_device_data *data);
static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
acpi_handle handle,
const union acpi_object *link,
struct list_head *list,
struct fwnode_handle *parent)
{
struct acpi_data_node *dn;
bool result;
dn = kzalloc(sizeof(*dn), GFP_KERNEL);
if (!dn)
return false;
dn->name = link->package.elements[0].string.pointer;
dn->fwnode.ops = &acpi_data_fwnode_ops;
dn->parent = parent;
INIT_LIST_HEAD(&dn->data.properties);
INIT_LIST_HEAD(&dn->data.subnodes);
result = acpi_extract_properties(desc, &dn->data);
if (handle) {
acpi_handle scope;
acpi_status status;
/*
* The scope for the subnode object lookup is the one of the
* namespace node (device) containing the object that has
* returned the package. That is, it's the scope of that
* object's parent.
*/
status = acpi_get_parent(handle, &scope);
if (ACPI_SUCCESS(status)
&& acpi_enumerate_nondev_subnodes(scope, desc, &dn->data,
&dn->fwnode))
result = true;
} else if (acpi_enumerate_nondev_subnodes(NULL, desc, &dn->data,
&dn->fwnode)) {
result = true;
}
if (result) {
dn->handle = handle;
dn->data.pointer = desc;
list_add_tail(&dn->sibling, list);
return true;
}
kfree(dn);
acpi_handle_debug(handle, "Invalid properties/subnodes data, skipping\n");
return false;
}
static bool acpi_nondev_subnode_data_ok(acpi_handle handle,
const union acpi_object *link,
struct list_head *list,
struct fwnode_handle *parent)
{
struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
acpi_status status;
status = acpi_evaluate_object_typed(handle, NULL, NULL, &buf,
ACPI_TYPE_PACKAGE);
if (ACPI_FAILURE(status))
return false;
if (acpi_nondev_subnode_extract(buf.pointer, handle, link, list,
parent))
return true;
ACPI_FREE(buf.pointer);
return false;
}
static bool acpi_nondev_subnode_ok(acpi_handle scope,
const union acpi_object *link,
struct list_head *list,
struct fwnode_handle *parent)
{
acpi_handle handle;
acpi_status status;
if (!scope)
return false;
status = acpi_get_handle(scope, link->package.elements[1].string.pointer,
&handle);
if (ACPI_FAILURE(status))
return false;
return acpi_nondev_subnode_data_ok(handle, link, list, parent);
}
static int acpi_add_nondev_subnodes(acpi_handle scope,
const union acpi_object *links,
struct list_head *list,
struct fwnode_handle *parent)
{
bool ret = false;
int i;
for (i = 0; i < links->package.count; i++) {
const union acpi_object *link, *desc;
acpi_handle handle;
bool result;
link = &links->package.elements[i];
/* Only two elements allowed. */
if (link->package.count != 2)
continue;
/* The first one must be a string. */
if (link->package.elements[0].type != ACPI_TYPE_STRING)
continue;
/* The second one may be a string, a reference or a package. */
switch (link->package.elements[1].type) {
case ACPI_TYPE_STRING:
result = acpi_nondev_subnode_ok(scope, link, list,
parent);
break;
case ACPI_TYPE_LOCAL_REFERENCE:
handle = link->package.elements[1].reference.handle;
result = acpi_nondev_subnode_data_ok(handle, link, list,
parent);
break;
case ACPI_TYPE_PACKAGE:
desc = &link->package.elements[1];
result = acpi_nondev_subnode_extract(desc, NULL, link,
list, parent);
break;
default:
result = false;
break;
}
ret = ret || result;
}
return ret;
}
static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
const union acpi_object *desc,
struct acpi_device_data *data,
struct fwnode_handle *parent)
{
int i;
/* Look for the ACPI data subnodes GUID. */
for (i = 0; i < desc->package.count; i += 2) {
const union acpi_object *guid, *links;
guid = &desc->package.elements[i];
links = &desc->package.elements[i + 1];
/*
* The first element must be a GUID and the second one must be
* a package.
*/
if (guid->type != ACPI_TYPE_BUFFER ||
guid->buffer.length != 16 ||
links->type != ACPI_TYPE_PACKAGE)
break;
if (!guid_equal((guid_t *)guid->buffer.pointer, &ads_guid))
continue;
return acpi_add_nondev_subnodes(scope, links, &data->subnodes,
parent);
}
return false;
}
static bool acpi_property_value_ok(const union acpi_object *value)
{
int j;
/*
* The value must be an integer, a string, a reference, or a package
* whose every element must be an integer, a string, or a reference.
*/
switch (value->type) {
case ACPI_TYPE_INTEGER:
case ACPI_TYPE_STRING:
case ACPI_TYPE_LOCAL_REFERENCE:
return true;
case ACPI_TYPE_PACKAGE:
for (j = 0; j < value->package.count; j++)
switch (value->package.elements[j].type) {
case ACPI_TYPE_INTEGER:
case ACPI_TYPE_STRING:
case ACPI_TYPE_LOCAL_REFERENCE:
continue;
default:
return false;
}
return true;
}
return false;
}
static bool acpi_properties_format_valid(const union acpi_object *properties)
{
int i;
for (i = 0; i < properties->package.count; i++) {
const union acpi_object *property;
property = &properties->package.elements[i];
/*
* Only two elements allowed, the first one must be a string and
* the second one has to satisfy certain conditions.
*/
if (property->package.count != 2
|| property->package.elements[0].type != ACPI_TYPE_STRING
|| !acpi_property_value_ok(&property->package.elements[1]))
return false;
}
return true;
}
static void acpi_init_of_compatible(struct acpi_device *adev)
{
const union acpi_object *of_compatible;
int ret;
ret = acpi_data_get_property_array(&adev->data, "compatible",
ACPI_TYPE_STRING, &of_compatible);
if (ret) {
ret = acpi_dev_get_property(adev, "compatible",
ACPI_TYPE_STRING, &of_compatible);
if (ret) {
if (adev->parent
&& adev->parent->flags.of_compatible_ok)
goto out;
return;
}
}
adev->data.of_compatible = of_compatible;
out:
adev->flags.of_compatible_ok = 1;
}
static bool acpi_is_property_guid(const guid_t *guid)
{
int i;
for (i = 0; i < ARRAY_SIZE(prp_guids); i++) {
if (guid_equal(guid, &prp_guids[i]))
return true;
}
return false;
}
struct acpi_device_properties *
acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
const union acpi_object *properties)
{
struct acpi_device_properties *props;
props = kzalloc(sizeof(*props), GFP_KERNEL);
if (props) {
INIT_LIST_HEAD(&props->list);
props->guid = guid;
props->properties = properties;
list_add_tail(&props->list, &data->properties);
}
return props;
}
static bool acpi_extract_properties(const union acpi_object *desc,
struct acpi_device_data *data)
{
int i;
if (desc->package.count % 2)
return false;
/* Look for the device properties GUID. */
for (i = 0; i < desc->package.count; i += 2) {
const union acpi_object *guid, *properties;
guid = &desc->package.elements[i];
properties = &desc->package.elements[i + 1];
/*
* The first element must be a GUID and the second one must be
* a package.
*/
if (guid->type != ACPI_TYPE_BUFFER ||
guid->buffer.length != 16 ||
properties->type != ACPI_TYPE_PACKAGE)
break;
if (!acpi_is_property_guid((guid_t *)guid->buffer.pointer))
continue;
/*
* We found the matching GUID. Now validate the format of the
* package immediately following it.
*/
if (!acpi_properties_format_valid(properties))
continue;
acpi_data_add_props(data, (const guid_t *)guid->buffer.pointer,
properties);
}
return !list_empty(&data->properties);
}
void acpi_init_properties(struct acpi_device *adev)
{
struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
struct acpi_hardware_id *hwid;
acpi_status status;
bool acpi_of = false;
INIT_LIST_HEAD(&adev->data.properties);
INIT_LIST_HEAD(&adev->data.subnodes);
if (!adev->handle)
return;
/*
* Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
* Device Tree compatible properties for this device.
*/
list_for_each_entry(hwid, &adev->pnp.ids, list) {
if (!strcmp(hwid->id, ACPI_DT_NAMESPACE_HID)) {
acpi_of = true;
break;
}
}
status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
ACPI_TYPE_PACKAGE);
if (ACPI_FAILURE(status))
goto out;
if (acpi_extract_properties(buf.pointer, &adev->data)) {
adev->data.pointer = buf.pointer;
if (acpi_of)
acpi_init_of_compatible(adev);
}
if (acpi_enumerate_nondev_subnodes(adev->handle, buf.pointer,
&adev->data, acpi_fwnode_handle(adev)))
adev->data.pointer = buf.pointer;
if (!adev->data.pointer) {
acpi_handle_debug(adev->handle, "Invalid _DSD data, skipping\n");
ACPI_FREE(buf.pointer);
}
out:
if (acpi_of && !adev->flags.of_compatible_ok)
acpi_handle_info(adev->handle,
ACPI_DT_NAMESPACE_HID " requires 'compatible' property\n");
if (!adev->data.pointer)
acpi_extract_apple_properties(adev);
}
static void acpi_destroy_nondev_subnodes(struct list_head *list)
{
struct acpi_data_node *dn, *next;
if (list_empty(list))
return;
list_for_each_entry_safe_reverse(dn, next, list, sibling) {
acpi_destroy_nondev_subnodes(&dn->data.subnodes);
wait_for_completion(&dn->kobj_done);
list_del(&dn->sibling);
ACPI_FREE((void *)dn->data.pointer);
kfree(dn);
}
}
void acpi_free_properties(struct acpi_device *adev)
{
struct acpi_device_properties *props, *tmp;
acpi_destroy_nondev_subnodes(&adev->data.subnodes);
ACPI_FREE((void *)adev->data.pointer);
adev->data.of_compatible = NULL;
adev->data.pointer = NULL;
list_for_each_entry_safe(props, tmp, &adev->data.properties, list) {
list_del(&props->list);
kfree(props);
}
}
/**
* acpi_data_get_property - return an ACPI property with given name
* @data: ACPI device deta object to get the property from
* @name: Name of the property
* @type: Expected property type
* @obj: Location to store the property value (if not %NULL)
*
* Look up a property with @name and store a pointer to the resulting ACPI
* object at the location pointed to by @obj if found.
*
* Callers must not attempt to free the returned objects. These objects will be
* freed by the ACPI core automatically during the removal of @data.
*
* Return: %0 if property with @name has been found (success),
* %-EINVAL if the arguments are invalid,
* %-EINVAL if the property doesn't exist,
* %-EPROTO if the property value type doesn't match @type.
*/
static int acpi_data_get_property(const struct acpi_device_data *data,
const char *name, acpi_object_type type,
const union acpi_object **obj)
{
const struct acpi_device_properties *props;
if (!data || !name)
return -EINVAL;
if (!data->pointer || list_empty(&data->properties))
return -EINVAL;
list_for_each_entry(props, &data->properties, list) {
const union acpi_object *properties;
unsigned int i;
properties = props->properties;
for (i = 0; i < properties->package.count; i++) {
const union acpi_object *propname, *propvalue;
const union acpi_object *property;
property = &properties->package.elements[i];
propname = &property->package.elements[0];
propvalue = &property->package.elements[1];
if (!strcmp(name, propname->string.pointer)) {
if (type != ACPI_TYPE_ANY &&
propvalue->type != type)
return -EPROTO;
if (obj)
*obj = propvalue;
return 0;
}
}
}
return -EINVAL;
}
/**
* acpi_dev_get_property - return an ACPI property with given name.
* @adev: ACPI device to get the property from.
* @name: Name of the property.
* @type: Expected property type.
* @obj: Location to store the property value (if not %NULL).
*/
int acpi_dev_get_property(const struct acpi_device *adev, const char *name,
acpi_object_type type, const union acpi_object **obj)
{
return adev ? acpi_data_get_property(&adev->data, name, type, obj) : -EINVAL;
}
EXPORT_SYMBOL_GPL(acpi_dev_get_property);
static const struct acpi_device_data *
acpi_device_data_of_node(const struct fwnode_handle *fwnode)
{
if (is_acpi_device_node(fwnode)) {
const struct acpi_device *adev = to_acpi_device_node(fwnode);
return &adev->data;
} else if (is_acpi_data_node(fwnode)) {
const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
return &dn->data;
}
return NULL;
}
/**
* acpi_node_prop_get - return an ACPI property with given name.
* @fwnode: Firmware node to get the property from.
* @propname: Name of the property.
* @valptr: Location to store a pointer to the property value (if not %NULL).
*/
int acpi_node_prop_get(const struct fwnode_handle *fwnode,
const char *propname, void **valptr)
{
return acpi_data_get_property(acpi_device_data_of_node(fwnode),
propname, ACPI_TYPE_ANY,
(const union acpi_object **)valptr);
}
/**
* acpi_data_get_property_array - return an ACPI array property with given name
* @adev: ACPI data object to get the property from
* @name: Name of the property
* @type: Expected type of array elements
* @obj: Location to store a pointer to the property value (if not NULL)
*
* Look up an array property with @name and store a pointer to the resulting
* ACPI object at the location pointed to by @obj if found.
*
* Callers must not attempt to free the returned objects. Those objects will be
* freed by the ACPI core automatically during the removal of @data.
*
* Return: %0 if array property (package) with @name has been found (success),
* %-EINVAL if the arguments are invalid,
* %-EINVAL if the property doesn't exist,
* %-EPROTO if the property is not a package or the type of its elements
* doesn't match @type.
*/
static int acpi_data_get_property_array(const struct acpi_device_data *data,
const char *name,
acpi_object_type type,
const union acpi_object **obj)
{
const union acpi_object *prop;
int ret, i;
ret = acpi_data_get_property(data, name, ACPI_TYPE_PACKAGE, &prop);
if (ret)
return ret;
if (type != ACPI_TYPE_ANY) {
/* Check that all elements are of correct type. */
for (i = 0; i < prop->package.count; i++)
if (prop->package.elements[i].type != type)
return -EPROTO;
}
if (obj)
*obj = prop;
return 0;
}
static struct fwnode_handle *
acpi_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
const char *childname)
{
struct fwnode_handle *child;
/*
* Find first matching named child node of this fwnode.
* For ACPI this will be a data only sub-node.
*/
fwnode_for_each_child_node(fwnode, child)
if (acpi_data_node_match(child, childname))
return child;
return NULL;
}
/**
* __acpi_node_get_property_reference - returns handle to the referenced object
* @fwnode: Firmware node to get the property from
* @propname: Name of the property
* @index: Index of the reference to return
* @num_args: Maximum number of arguments after each reference
* @args: Location to store the returned reference with optional arguments
*
* Find property with @name, verifify that it is a package containing at least
* one object reference and if so, store the ACPI device object pointer to the
* target object in @args->adev. If the reference includes arguments, store
* them in the @args->args[] array.
*
* If there's more than one reference in the property value package, @index is
* used to select the one to return.
*
* It is possible to leave holes in the property value set like in the
* example below:
*
* Package () {
* "cs-gpios",
* Package () {
* ^GPIO, 19, 0, 0,
* ^GPIO, 20, 0, 0,
* 0,
* ^GPIO, 21, 0, 0,
* }
* }
*
* Calling this function with index %2 or index %3 return %-ENOENT. If the
* property does not contain any more values %-ENOENT is returned. The NULL
* entry must be single integer and preferably contain value %0.
*
* Return: %0 on success, negative error code on failure.
*/
int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
const char *propname, size_t index, size_t num_args,
struct fwnode_reference_args *args)
{
const union acpi_object *element, *end;
const union acpi_object *obj;
const struct acpi_device_data *data;
struct acpi_device *device;
int ret, idx = 0;
data = acpi_device_data_of_node(fwnode);
if (!data)
return -ENOENT;
ret = acpi_data_get_property(data, propname, ACPI_TYPE_ANY, &obj);
if (ret)
return ret == -EINVAL ? -ENOENT : -EINVAL;
/*
* The simplest case is when the value is a single reference. Just
* return that reference then.
*/
if (obj->type == ACPI_TYPE_LOCAL_REFERENCE) {
if (index)
return -EINVAL;
ret = acpi_bus_get_device(obj->reference.handle, &device);
if (ret)
return ret == -ENODEV ? -EINVAL : ret;
args->fwnode = acpi_fwnode_handle(device);
args->nargs = 0;
return 0;
}
/*
* If it is not a single reference, then it is a package of
* references followed by number of ints as follows:
*
* Package () { REF, INT, REF, INT, INT }
*
* The index argument is then used to determine which reference
* the caller wants (along with the arguments).
*/
if (obj->type != ACPI_TYPE_PACKAGE)
return -EINVAL;
if (index >= obj->package.count)
return -ENOENT;
element = obj->package.elements;
end = element + obj->package.count;
while (element < end) {
u32 nargs, i;
if (element->type == ACPI_TYPE_LOCAL_REFERENCE) {
struct fwnode_handle *ref_fwnode;
ret = acpi_bus_get_device(element->reference.handle,
&device);
if (ret)
return -EINVAL;
nargs = 0;
element++;
/*
* Find the referred data extension node under the
* referred device node.
*/
for (ref_fwnode = acpi_fwnode_handle(device);
element < end && element->type == ACPI_TYPE_STRING;
element++) {
ref_fwnode = acpi_fwnode_get_named_child_node(
ref_fwnode, element->string.pointer);
if (!ref_fwnode)
return -EINVAL;
}
/* assume following integer elements are all args */
for (i = 0; element + i < end && i < num_args; i++) {
int type = element[i].type;
if (type == ACPI_TYPE_INTEGER)
nargs++;
else if (type == ACPI_TYPE_LOCAL_REFERENCE)
break;
else
return -EINVAL;
}
if (nargs > NR_FWNODE_REFERENCE_ARGS)
return -EINVAL;
if (idx == index) {
args->fwnode = ref_fwnode;
args->nargs = nargs;
for (i = 0; i < nargs; i++)
args->args[i] = element[i].integer.value;
return 0;
}
element += nargs;
} else if (element->type == ACPI_TYPE_INTEGER) {
if (idx == index)
return -ENOENT;
element++;
} else {
return -EINVAL;
}
idx++;
}
return -ENOENT;
}
EXPORT_SYMBOL_GPL(__acpi_node_get_property_reference);
static int acpi_data_prop_read_single(const struct acpi_device_data *data,
const char *propname,
enum dev_prop_type proptype, void *val)
{
const union acpi_object *obj;
int ret;
if (!val)
return -EINVAL;
if (proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64) {
ret = acpi_data_get_property(data, propname, ACPI_TYPE_INTEGER, &obj);
if (ret)
return ret;
switch (proptype) {
case DEV_PROP_U8:
if (obj->integer.value > U8_MAX)
return -EOVERFLOW;
*(u8 *)val = obj->integer.value;
break;
case DEV_PROP_U16:
if (obj->integer.value > U16_MAX)
return -EOVERFLOW;
*(u16 *)val = obj->integer.value;
break;
case DEV_PROP_U32:
if (obj->integer.value > U32_MAX)
return -EOVERFLOW;
*(u32 *)val = obj->integer.value;
break;
default:
*(u64 *)val = obj->integer.value;
break;
}
} else if (proptype == DEV_PROP_STRING) {
ret = acpi_data_get_property(data, propname, ACPI_TYPE_STRING, &obj);
if (ret)
return ret;
*(char **)val = obj->string.pointer;
return 1;
} else {
ret = -EINVAL;
}
return ret;
}
int acpi_dev_prop_read_single(struct acpi_device *adev, const char *propname,
enum dev_prop_type proptype, void *val)
{
int ret;
if (!adev)
return -EINVAL;
ret = acpi_data_prop_read_single(&adev->data, propname, proptype, val);
if (ret < 0 || proptype != ACPI_TYPE_STRING)
return ret;
return 0;
}
static int acpi_copy_property_array_u8(const union acpi_object *items, u8 *val,
size_t nval)
{
int i;
for (i = 0; i < nval; i++) {
if (items[i].type != ACPI_TYPE_INTEGER)
return -EPROTO;
if (items[i].integer.value > U8_MAX)
return -EOVERFLOW;
val[i] = items[i].integer.value;
}
return 0;
}
static int acpi_copy_property_array_u16(const union acpi_object *items,
u16 *val, size_t nval)
{
int i;
for (i = 0; i < nval; i++) {
if (items[i].type != ACPI_TYPE_INTEGER)
return -EPROTO;
if (items[i].integer.value > U16_MAX)
return -EOVERFLOW;
val[i] = items[i].integer.value;
}
return 0;
}
static int acpi_copy_property_array_u32(const union acpi_object *items,
u32 *val, size_t nval)
{
int i;
for (i = 0; i < nval; i++) {
if (items[i].type != ACPI_TYPE_INTEGER)
return -EPROTO;
if (items[i].integer.value > U32_MAX)
return -EOVERFLOW;
val[i] = items[i].integer.value;
}
return 0;
}
static int acpi_copy_property_array_u64(const union acpi_object *items,
u64 *val, size_t nval)
{
int i;
for (i = 0; i < nval; i++) {
if (items[i].type != ACPI_TYPE_INTEGER)
return -EPROTO;
val[i] = items[i].integer.value;
}
return 0;
}
static int acpi_copy_property_array_string(const union acpi_object *items,
char **val, size_t nval)
{
int i;
for (i = 0; i < nval; i++) {
if (items[i].type != ACPI_TYPE_STRING)
return -EPROTO;
val[i] = items[i].string.pointer;
}
return nval;
}
static int acpi_data_prop_read(const struct acpi_device_data *data,
const char *propname,
enum dev_prop_type proptype,
void *val, size_t nval)
{
const union acpi_object *obj;
const union acpi_object *items;
int ret;
if (val && nval == 1) {
ret = acpi_data_prop_read_single(data, propname, proptype, val);
if (ret >= 0)
return ret;
}
ret = acpi_data_get_property_array(data, propname, ACPI_TYPE_ANY, &obj);
if (ret)
return ret;
if (!val)
return obj->package.count;
if (proptype != DEV_PROP_STRING && nval > obj->package.count)
return -EOVERFLOW;
else if (nval <= 0)
return -EINVAL;
items = obj->package.elements;
switch (proptype) {
case DEV_PROP_U8:
ret = acpi_copy_property_array_u8(items, (u8 *)val, nval);
break;
case DEV_PROP_U16:
ret = acpi_copy_property_array_u16(items, (u16 *)val, nval);
break;
case DEV_PROP_U32:
ret = acpi_copy_property_array_u32(items, (u32 *)val, nval);
break;
case DEV_PROP_U64:
ret = acpi_copy_property_array_u64(items, (u64 *)val, nval);
break;
case DEV_PROP_STRING:
ret = acpi_copy_property_array_string(
items, (char **)val,
min_t(u32, nval, obj->package.count));
break;
default:
ret = -EINVAL;
break;
}
return ret;
}
int acpi_dev_prop_read(const struct acpi_device *adev, const char *propname,
enum dev_prop_type proptype, void *val, size_t nval)
{
return adev ? acpi_data_prop_read(&adev->data, propname, proptype, val, nval) : -EINVAL;
}
/**
* acpi_node_prop_read - retrieve the value of an ACPI property with given name.
* @fwnode: Firmware node to get the property from.
* @propname: Name of the property.
* @proptype: Expected property type.
* @val: Location to store the property value (if not %NULL).
* @nval: Size of the array pointed to by @val.
*
* If @val is %NULL, return the number of array elements comprising the value
* of the property. Otherwise, read at most @nval values to the array at the
* location pointed to by @val.
*/
int acpi_node_prop_read(const struct fwnode_handle *fwnode,
const char *propname, enum dev_prop_type proptype,
void *val, size_t nval)
{
return acpi_data_prop_read(acpi_device_data_of_node(fwnode),
propname, proptype, val, nval);
}
/**
* acpi_get_next_subnode - Return the next child node handle for a fwnode
* @fwnode: Firmware node to find the next child node for.
* @child: Handle to one of the device's child nodes or a null handle.
*/
struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
struct fwnode_handle *child)
{
const struct acpi_device *adev = to_acpi_device_node(fwnode);
const struct list_head *head;
struct list_head *next;
if (!child || is_acpi_device_node(child)) {
struct acpi_device *child_adev;
if (adev)
head = &adev->children;
else
goto nondev;
if (list_empty(head))
goto nondev;
if (child) {
adev = to_acpi_device_node(child);
next = adev->node.next;
if (next == head) {
child = NULL;
goto nondev;
}
child_adev = list_entry(next, struct acpi_device, node);
} else {
child_adev = list_first_entry(head, struct acpi_device,
node);
}
return acpi_fwnode_handle(child_adev);
}
nondev:
if (!child || is_acpi_data_node(child)) {
const struct acpi_data_node *data = to_acpi_data_node(fwnode);
struct acpi_data_node *dn;
if (adev)
head = &adev->data.subnodes;
else if (data)
head = &data->data.subnodes;
else
return NULL;
if (list_empty(head))
return NULL;
if (child) {
dn = to_acpi_data_node(child);
next = dn->sibling.next;
if (next == head)
return NULL;
dn = list_entry(next, struct acpi_data_node, sibling);
} else {
dn = list_first_entry(head, struct acpi_data_node, sibling);
}
return &dn->fwnode;
}
return NULL;
}
/**
* acpi_node_get_parent - Return parent fwnode of this fwnode
* @fwnode: Firmware node whose parent to get
*
* Returns parent node of an ACPI device or data firmware node or %NULL if
* not available.
*/
struct fwnode_handle *acpi_node_get_parent(const struct fwnode_handle *fwnode)
{
if (is_acpi_data_node(fwnode)) {
/* All data nodes have parent pointer so just return that */
return to_acpi_data_node(fwnode)->parent;
} else if (is_acpi_device_node(fwnode)) {
acpi_handle handle, parent_handle;
handle = to_acpi_device_node(fwnode)->handle;
if (ACPI_SUCCESS(acpi_get_parent(handle, &parent_handle))) {
struct acpi_device *adev;
if (!acpi_bus_get_device(parent_handle, &adev))
return acpi_fwnode_handle(adev);
}
}
return NULL;
}
/*
* Return true if the node is an ACPI graph node. Called on either ports
* or endpoints.
*/
static bool is_acpi_graph_node(struct fwnode_handle *fwnode,
const char *str)
{
unsigned int len = strlen(str);
const char *name;
if (!len || !is_acpi_data_node(fwnode))
return false;
name = to_acpi_data_node(fwnode)->name;
return (fwnode_property_present(fwnode, "reg") &&
!strncmp(name, str, len) && name[len] == '@') ||
fwnode_property_present(fwnode, str);
}
/**
* acpi_graph_get_next_endpoint - Get next endpoint ACPI firmware node
* @fwnode: Pointer to the parent firmware node
* @prev: Previous endpoint node or %NULL to get the first
*
* Looks up next endpoint ACPI firmware node below a given @fwnode. Returns
* %NULL if there is no next endpoint or in case of error. In case of success
* the next endpoint is returned.
*/
static struct fwnode_handle *acpi_graph_get_next_endpoint(
const struct fwnode_handle *fwnode, struct fwnode_handle *prev)
{
struct fwnode_handle *port = NULL;
struct fwnode_handle *endpoint;
if (!prev) {
do {
port = fwnode_get_next_child_node(fwnode, port);
/*
* The names of the port nodes begin with "port@"
* followed by the number of the port node and they also
* have a "reg" property that also has the number of the
* port node. For compatibility reasons a node is also
* recognised as a port node from the "port" property.
*/
if (is_acpi_graph_node(port, "port"))
break;
} while (port);
} else {
port = fwnode_get_parent(prev);
}
if (!port)
return NULL;
endpoint = fwnode_get_next_child_node(port, prev);
while (!endpoint) {
port = fwnode_get_next_child_node(fwnode, port);
if (!port)
break;
if (is_acpi_graph_node(port, "port"))
endpoint = fwnode_get_next_child_node(port, NULL);
}
/*
* The names of the endpoint nodes begin with "endpoint@" followed by
* the number of the endpoint node and they also have a "reg" property
* that also has the number of the endpoint node. For compatibility
* reasons a node is also recognised as an endpoint node from the
* "endpoint" property.
*/
if (!is_acpi_graph_node(endpoint, "endpoint"))
return NULL;
return endpoint;
}
/**
* acpi_graph_get_child_prop_value - Return a child with a given property value
* @fwnode: device fwnode
* @prop_name: The name of the property to look for
* @val: the desired property value
*
* Return the port node corresponding to a given port number. Returns
* the child node on success, NULL otherwise.
*/
static struct fwnode_handle *acpi_graph_get_child_prop_value(
const struct fwnode_handle *fwnode, const char *prop_name,
unsigned int val)
{
struct fwnode_handle *child;
fwnode_for_each_child_node(fwnode, child) {
u32 nr;
if (fwnode_property_read_u32(child, prop_name, &nr))
continue;
if (val == nr)
return child;
}
return NULL;
}
/**
* acpi_graph_get_remote_enpoint - Parses and returns remote end of an endpoint
* @fwnode: Endpoint firmware node pointing to a remote device
* @endpoint: Firmware node of remote endpoint is filled here if not %NULL
*
* Returns the remote endpoint corresponding to @__fwnode. NULL on error.
*/
static struct fwnode_handle *
acpi_graph_get_remote_endpoint(const struct fwnode_handle *__fwnode)
{
struct fwnode_handle *fwnode;
unsigned int port_nr, endpoint_nr;
struct fwnode_reference_args args;
int ret;
memset(&args, 0, sizeof(args));
ret = acpi_node_get_property_reference(__fwnode, "remote-endpoint", 0,
&args);
if (ret)
return NULL;
/* Direct endpoint reference? */
if (!is_acpi_device_node(args.fwnode))
return args.nargs ? NULL : args.fwnode;
/*
* Always require two arguments with the reference: port and
* endpoint indices.
*/
if (args.nargs != 2)
return NULL;
fwnode = args.fwnode;
port_nr = args.args[0];
endpoint_nr = args.args[1];
fwnode = acpi_graph_get_child_prop_value(fwnode, "port", port_nr);
return acpi_graph_get_child_prop_value(fwnode, "endpoint", endpoint_nr);
}
static bool acpi_fwnode_device_is_available(const struct fwnode_handle *fwnode)
{
if (!is_acpi_device_node(fwnode))
return false;
return acpi_device_is_present(to_acpi_device_node(fwnode));
}
static bool acpi_fwnode_property_present(const struct fwnode_handle *fwnode,
const char *propname)
{
return !acpi_node_prop_get(fwnode, propname, NULL);
}
static int
acpi_fwnode_property_read_int_array(const struct fwnode_handle *fwnode,
const char *propname,
unsigned int elem_size, void *val,
size_t nval)
{
enum dev_prop_type type;
switch (elem_size) {
case sizeof(u8):
type = DEV_PROP_U8;
break;
case sizeof(u16):
type = DEV_PROP_U16;
break;
case sizeof(u32):
type = DEV_PROP_U32;
break;
case sizeof(u64):
type = DEV_PROP_U64;
break;
default:
return -ENXIO;
}
return acpi_node_prop_read(fwnode, propname, type, val, nval);
}
static int
acpi_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
const char *propname, const char **val,
size_t nval)
{
return acpi_node_prop_read(fwnode, propname, DEV_PROP_STRING,
val, nval);
}
static int
acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
const char *prop, const char *nargs_prop,
unsigned int args_count, unsigned int index,
struct fwnode_reference_args *args)
{
return __acpi_node_get_property_reference(fwnode, prop, index,
args_count, args);
}
static struct fwnode_handle *
acpi_fwnode_get_parent(struct fwnode_handle *fwnode)
{
return acpi_node_get_parent(fwnode);
}
static int acpi_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
struct fwnode_endpoint *endpoint)
{
struct fwnode_handle *port_fwnode = fwnode_get_parent(fwnode);
endpoint->local_fwnode = fwnode;
if (fwnode_property_read_u32(port_fwnode, "reg", &endpoint->port))
fwnode_property_read_u32(port_fwnode, "port", &endpoint->port);
if (fwnode_property_read_u32(fwnode, "reg", &endpoint->id))
fwnode_property_read_u32(fwnode, "endpoint", &endpoint->id);
return 0;
}
static const void *
acpi_fwnode_device_get_match_data(const struct fwnode_handle *fwnode,
const struct device *dev)
{
return acpi_device_get_match_data(dev);
}
#define DECLARE_ACPI_FWNODE_OPS(ops) \
const struct fwnode_operations ops = { \
.device_is_available = acpi_fwnode_device_is_available, \
.device_get_match_data = acpi_fwnode_device_get_match_data, \
.property_present = acpi_fwnode_property_present, \
.property_read_int_array = \
acpi_fwnode_property_read_int_array, \
.property_read_string_array = \
acpi_fwnode_property_read_string_array, \
.get_parent = acpi_node_get_parent, \
.get_next_child_node = acpi_get_next_subnode, \
.get_named_child_node = acpi_fwnode_get_named_child_node, \
.get_reference_args = acpi_fwnode_get_reference_args, \
.graph_get_next_endpoint = \
acpi_graph_get_next_endpoint, \
.graph_get_remote_endpoint = \
acpi_graph_get_remote_endpoint, \
.graph_get_port_parent = acpi_fwnode_get_parent, \
.graph_parse_endpoint = acpi_fwnode_graph_parse_endpoint, \
}; \
EXPORT_SYMBOL_GPL(ops)
DECLARE_ACPI_FWNODE_OPS(acpi_device_fwnode_ops);
DECLARE_ACPI_FWNODE_OPS(acpi_data_fwnode_ops);
const struct fwnode_operations acpi_static_fwnode_ops;
bool is_acpi_device_node(const struct fwnode_handle *fwnode)
{
return !IS_ERR_OR_NULL(fwnode) &&
fwnode->ops == &acpi_device_fwnode_ops;
}
EXPORT_SYMBOL(is_acpi_device_node);
bool is_acpi_data_node(const struct fwnode_handle *fwnode)
{
return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &acpi_data_fwnode_ops;
}
EXPORT_SYMBOL(is_acpi_data_node);