PCI: Export ACPI _DSM provided firmware instance number and string name to sysfs

This patch exports ACPI _DSM (Device Specific Method) provided firmware
instance number and string name of PCI devices as defined by 'PCI
Firmware Specification Revision 3.1' section 4.6.7.( DSM for Naming a
PCI or PCI Express Device Under Operating Systems) to sysfs.

New files created are:
  /sys/bus/pci/devices/.../label which contains the firmware name for
the device in question, and
  /sys/bus/pci/devices/.../acpi_index which contains the firmware device type
instance for the given device.

cat /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/acpi_index
1
cat /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/label
Embedded Broadcom 5709C NIC 1

cat /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.1/acpi_index
2
cat /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.1/label
Embedded Broadcom 5709C NIC 2

The ACPI _DSM provided firmware 'instance number' and 'string name' will
be given priority if the firmware also provides 'SMBIOS type 41 device
type instance and string'.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Jordan Hargrave <jordan_hargrave@dell.com>
Signed-off-by: Narendra K <narendra_k@dell.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Narendra_K@Dell.com 2011-03-02 22:34:17 +05:30 committed by Jesse Barnes
parent cdb9755849
commit 6058989bad
5 changed files with 270 additions and 15 deletions

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@ -145,9 +145,11 @@ Date: July 2010
Contact: Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
Description:
Reading this attribute will provide the firmware
given name(SMBIOS type 41 string) of the PCI device.
The attribute will be created only if the firmware
has given a name to the PCI device.
given name (SMBIOS type 41 string or ACPI _DSM string) of
the PCI device. The attribute will be created only
if the firmware has given a name to the PCI device.
ACPI _DSM string name will be given priority if the
system firmware provides SMBIOS type 41 string also.
Users:
Userspace applications interested in knowing the
firmware assigned name of the PCI device.
@ -157,12 +159,27 @@ Date: July 2010
Contact: Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
Description:
Reading this attribute will provide the firmware
given instance(SMBIOS type 41 device type instance)
of the PCI device. The attribute will be created
only if the firmware has given a device type instance
to the PCI device.
given instance (SMBIOS type 41 device type instance) of the
PCI device. The attribute will be created only if the firmware
has given an instance number to the PCI device.
Users:
Userspace applications interested in knowing the
firmware assigned device type instance of the PCI
device that can help in understanding the firmware
intended order of the PCI device.
What: /sys/bus/pci/devices/.../acpi_index
Date: July 2010
Contact: Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
Description:
Reading this attribute will provide the firmware
given instance (ACPI _DSM instance number) of the PCI device.
The attribute will be created only if the firmware has given
an instance number to the PCI device. ACPI _DSM instance number
will be given priority if the system firmware provides SMBIOS
type 41 device type instance also.
Users:
Userspace applications interested in knowing the
firmware assigned instance number of the PCI
device that can help in understanding the firmware
intended order of the PCI device.

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@ -87,3 +87,5 @@ config PCI_IOAPIC
depends on ACPI
depends on HOTPLUG
default y
select NLS if (DMI || ACPI)

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@ -53,8 +53,9 @@ obj-$(CONFIG_TILE) += setup-bus.o setup-irq.o
#
# ACPI Related PCI FW Functions
# ACPI _DSM provided firmware instance and string name
#
obj-$(CONFIG_ACPI) += pci-acpi.o
obj-$(CONFIG_ACPI) += pci-acpi.o pci-label.o
# SMBIOS provided firmware instance and labels
obj-$(CONFIG_DMI) += pci-label.o

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@ -5,6 +5,13 @@
* by Narendra K <Narendra_K@dell.com>,
* Jordan Hargrave <Jordan_Hargrave@dell.com>
*
* PCI Firmware Specification Revision 3.1 section 4.6.7 (DSM for Naming a
* PCI or PCI Express Device Under Operating Systems) defines an instance
* number and string name. This code retrieves them and exports them to sysfs.
* If the system firmware does not provide the ACPI _DSM (Device Specific
* Method), then the SMBIOS type 41 instance number and string is exported to
* sysfs.
*
* SMBIOS defines type 41 for onboard pci devices. This code retrieves
* the instance number and string from the type 41 record and exports
* it to sysfs.
@ -19,8 +26,30 @@
#include <linux/pci_ids.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/nls.h>
#include <linux/acpi.h>
#include <linux/pci-acpi.h>
#include <acpi/acpi_drivers.h>
#include <acpi/acpi_bus.h>
#include "pci.h"
#define DEVICE_LABEL_DSM 0x07
#ifndef CONFIG_DMI
static inline int
pci_create_smbiosname_file(struct pci_dev *pdev)
{
return -1;
}
static inline void
pci_remove_smbiosname_file(struct pci_dev *pdev)
{
}
#else
enum smbios_attr_enum {
SMBIOS_ATTR_NONE = 0,
SMBIOS_ATTR_LABEL_SHOW,
@ -120,9 +149,7 @@ static struct attribute_group smbios_attr_group = {
static int
pci_create_smbiosname_file(struct pci_dev *pdev)
{
if (!sysfs_create_group(&pdev->dev.kobj, &smbios_attr_group))
return 0;
return -ENODEV;
return sysfs_create_group(&pdev->dev.kobj, &smbios_attr_group);
}
static void
@ -131,13 +158,221 @@ pci_remove_smbiosname_file(struct pci_dev *pdev)
sysfs_remove_group(&pdev->dev.kobj, &smbios_attr_group);
}
#endif
#ifndef CONFIG_ACPI
static inline int
pci_create_acpi_index_label_files(struct pci_dev *pdev)
{
return -1;
}
static inline int
pci_remove_acpi_index_label_files(struct pci_dev *pdev)
{
return -1;
}
#else
static const char device_label_dsm_uuid[] = {
0xD0, 0x37, 0xC9, 0xE5, 0x53, 0x35, 0x7A, 0x4D,
0x91, 0x17, 0xEA, 0x4D, 0x19, 0xC3, 0x43, 0x4D
};
enum acpi_attr_enum {
ACPI_ATTR_NONE = 0,
ACPI_ATTR_LABEL_SHOW,
ACPI_ATTR_INDEX_SHOW,
};
static void dsm_label_utf16s_to_utf8s(union acpi_object *obj, char *buf)
{
int len;
len = utf16s_to_utf8s((const wchar_t *)obj->
package.elements[1].string.pointer,
obj->package.elements[1].string.length,
UTF16_LITTLE_ENDIAN,
buf, PAGE_SIZE);
buf[len] = '\n';
}
static int
dsm_get_label(acpi_handle handle, int func,
struct acpi_buffer *output,
char *buf, enum acpi_attr_enum attribute)
{
struct acpi_object_list input;
union acpi_object params[4];
union acpi_object *obj;
int len = 0;
int err;
input.count = 4;
input.pointer = params;
params[0].type = ACPI_TYPE_BUFFER;
params[0].buffer.length = sizeof(device_label_dsm_uuid);
params[0].buffer.pointer = (char *)device_label_dsm_uuid;
params[1].type = ACPI_TYPE_INTEGER;
params[1].integer.value = 0x02;
params[2].type = ACPI_TYPE_INTEGER;
params[2].integer.value = func;
params[3].type = ACPI_TYPE_PACKAGE;
params[3].package.count = 0;
params[3].package.elements = NULL;
err = acpi_evaluate_object(handle, "_DSM", &input, output);
if (err)
return -1;
obj = (union acpi_object *)output->pointer;
switch (obj->type) {
case ACPI_TYPE_PACKAGE:
if (obj->package.count != 2)
break;
len = obj->package.elements[0].integer.value;
if (buf) {
if (attribute == ACPI_ATTR_INDEX_SHOW)
scnprintf(buf, PAGE_SIZE, "%llu\n",
obj->package.elements[0].integer.value);
else if (attribute == ACPI_ATTR_LABEL_SHOW)
dsm_label_utf16s_to_utf8s(obj, buf);
kfree(output->pointer);
return strlen(buf);
}
kfree(output->pointer);
return len;
break;
default:
kfree(output->pointer);
}
return -1;
}
static bool
device_has_dsm(struct device *dev)
{
acpi_handle handle;
struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
handle = DEVICE_ACPI_HANDLE(dev);
if (!handle)
return FALSE;
if (dsm_get_label(handle, DEVICE_LABEL_DSM, &output, NULL,
ACPI_ATTR_NONE) > 0)
return TRUE;
return FALSE;
}
static mode_t
acpi_index_string_exist(struct kobject *kobj, struct attribute *attr, int n)
{
struct device *dev;
dev = container_of(kobj, struct device, kobj);
if (device_has_dsm(dev))
return S_IRUGO;
return 0;
}
static ssize_t
acpilabel_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
acpi_handle handle;
int length;
handle = DEVICE_ACPI_HANDLE(dev);
if (!handle)
return -1;
length = dsm_get_label(handle, DEVICE_LABEL_DSM,
&output, buf, ACPI_ATTR_LABEL_SHOW);
if (length < 1)
return -1;
return length;
}
static ssize_t
acpiindex_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
acpi_handle handle;
int length;
handle = DEVICE_ACPI_HANDLE(dev);
if (!handle)
return -1;
length = dsm_get_label(handle, DEVICE_LABEL_DSM,
&output, buf, ACPI_ATTR_INDEX_SHOW);
if (length < 0)
return -1;
return length;
}
static struct device_attribute acpi_attr_label = {
.attr = {.name = "label", .mode = 0444},
.show = acpilabel_show,
};
static struct device_attribute acpi_attr_index = {
.attr = {.name = "acpi_index", .mode = 0444},
.show = acpiindex_show,
};
static struct attribute *acpi_attributes[] = {
&acpi_attr_label.attr,
&acpi_attr_index.attr,
NULL,
};
static struct attribute_group acpi_attr_group = {
.attrs = acpi_attributes,
.is_visible = acpi_index_string_exist,
};
static int
pci_create_acpi_index_label_files(struct pci_dev *pdev)
{
return sysfs_create_group(&pdev->dev.kobj, &acpi_attr_group);
}
static int
pci_remove_acpi_index_label_files(struct pci_dev *pdev)
{
sysfs_remove_group(&pdev->dev.kobj, &acpi_attr_group);
return 0;
}
#endif
void pci_create_firmware_label_files(struct pci_dev *pdev)
{
if (!pci_create_smbiosname_file(pdev))
;
if (device_has_dsm(&pdev->dev))
pci_create_acpi_index_label_files(pdev);
else
pci_create_smbiosname_file(pdev);
}
void pci_remove_firmware_label_files(struct pci_dev *pdev)
{
if (device_has_dsm(&pdev->dev))
pci_remove_acpi_index_label_files(pdev);
else
pci_remove_smbiosname_file(pdev);
}

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@ -11,7 +11,7 @@
extern int pci_uevent(struct device *dev, struct kobj_uevent_env *env);
extern int pci_create_sysfs_dev_files(struct pci_dev *pdev);
extern void pci_remove_sysfs_dev_files(struct pci_dev *pdev);
#ifndef CONFIG_DMI
#if !defined(CONFIG_DMI) && !defined(CONFIG_ACPI)
static inline void pci_create_firmware_label_files(struct pci_dev *pdev)
{ return; }
static inline void pci_remove_firmware_label_files(struct pci_dev *pdev)