Hello,
This patch exports ACPI _DSM provided firmware instance number and
string name to sysfs.
Please review -
From: Narendra K <narendra_k@xxxxxxxx>
Subject: [PATCH] Export ACPI _DSM provided firmware instance number and string 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/.../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/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/index
2
cat /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.1/label
Embedded Broadcom 5709C NIC 2
Signed-off-by: Jordan Hargrave <jordan_hargrave@xxxxxxxx>
Signed-off-by: Narendra K <narendra_k@xxxxxxxx>
---
Documentation/ABI/testing/sysfs-bus-pci | 14 +-
drivers/pci/Makefile | 3 +-
drivers/pci/pci-label.c | 236 ++++++++++++++++++++++++++++++-
drivers/pci/pci.h | 2 +-
4 files changed, 243 insertions(+), 12 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index f979d82..7e90ef1 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -145,9 +145,9 @@ Date: July 2010
Contact: Narendra K <narendra_k@xxxxxxxx>, linux-bugs@xxxxxxxx
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.
Users:
Userspace applications interested in knowing the
firmware assigned name of the PCI device.
@@ -157,10 +157,10 @@ Date: July 2010
Contact: Narendra K <narendra_k@xxxxxxxx>, linux-bugs@xxxxxxxx
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
+ or 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.
Users:
Userspace applications interested in knowing the
firmware assigned device type instance of the PCI
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 98e6fdf..bb1d3b2 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -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
diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c
index 90c0a72..08b1ec5 100644
--- a/drivers/pci/pci-label.c
+++ b/drivers/pci/pci-label.c
@@ -5,6 +5,13 @@
* by Narendra K <Narendra_K@xxxxxxxx>,
* Jordan Hargrave <Jordan_Hargrave@xxxxxxxx>
*
+ * 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,
@@ -131,13 +160,214 @@ 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 int dsm_label_utf16s_to_utf8s(union acpi_object *obj, char *buf)
+{
+ int err;
+ err = 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[err] = '\n';
+ return err;
+}
+
+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) {
+ if (dsm_label_utf16s_to_utf8s(obj, buf) < 0)
+ return -1;
+ }
+ kfree(output->pointer);
+ return strlen(buf);
+ }
+ kfree(output->pointer);
+ return len;
+ break;
+ default:
+ kfree(output->pointer);
+ }
+ return -1;
+}
+
+static mode_t
+acpi_index_string_exist(struct kobject *kobj, struct attribute *attr, int n)
+{
+ struct device *dev;
+ struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
+ acpi_handle handle;
+ int length;
+
+ dev = container_of(kobj, struct device, kobj);
+ handle = DEVICE_ACPI_HANDLE(dev);
+
+ if (!handle)
+ return 0;
+
+ length = dsm_get_label(handle, DEVICE_LABEL_DSM,
+ &output, NULL, ACPI_ATTR_NONE);
+
+ return (length > 0) ? S_IRUGO : 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 = "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)
+{
+ if (!sysfs_create_group(&pdev->dev.kobj, &acpi_attr_group))
+ return 0;
+ return -ENODEV;
+}
+
+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 (!pci_create_acpi_index_label_files(pdev))
+ return;
+ pci_create_smbiosname_file(pdev);
}
void pci_remove_firmware_label_files(struct pci_dev *pdev)
{
- pci_remove_smbiosname_file(pdev);
+ if (!pci_remove_acpi_index_label_files(pdev))
+ return;
+ else
+ pci_remove_smbiosname_file(pdev);
}
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 7d33f66..d0d0bd4 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -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)
--
1.7.3.1
With regards,
Narendra K--
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