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.
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.
* 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.
#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,
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
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)
{
- pci_remove_smbiosname_file(pdev);
+ if (device_has_dsm(&pdev->dev))
+ pci_remove_acpi_index_label_files(pdev);
+ else
+ pci_remove_smbiosname_file(pdev);
}