PCI: Export ACPI _DSM provided firmware instance number and string name to sysfs (6058989b) · Commits · 戴 / test

Documentation/ABI/testing/sysfs-bus-pci

+24 −7

Original line number	Diff line number	Diff line
		@@ -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.

drivers/pci/Kconfig

+2 −0

Original line number	Diff line number	Diff line
		@@ -87,3 +87,5 @@ config PCI_IOAPIC
		depends on ACPI
		depends on HOTPLUG
		default y

		select NLS if (DMI \|\| ACPI)

drivers/pci/Makefile

+2 −1

Original line number	Diff line number	Diff line
		@@ -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

drivers/pci/pci-label.c

+241 −6

Original line number	Diff line number	Diff line
		@@ -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);
		}

drivers/pci/pci.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -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)

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