From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- drivers/pci/pci-label.c | 311 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 311 insertions(+) create mode 100644 drivers/pci/pci-label.c (limited to 'drivers/pci/pci-label.c') diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c new file mode 100644 index 000000000..9fb4ef568 --- /dev/null +++ b/drivers/pci/pci-label.c @@ -0,0 +1,311 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Export the firmware instance and label associated with a PCI device to + * sysfs + * + * Copyright (C) 2010 Dell Inc. + * by Narendra K , + * Jordan Hargrave + * + * 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. + * + * Please see http://linux.dell.com/files/biosdevname/ for more + * information. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "pci.h" + +#ifdef CONFIG_DMI +enum smbios_attr_enum { + SMBIOS_ATTR_NONE = 0, + SMBIOS_ATTR_LABEL_SHOW, + SMBIOS_ATTR_INSTANCE_SHOW, +}; + +static size_t find_smbios_instance_string(struct pci_dev *pdev, char *buf, + enum smbios_attr_enum attribute) +{ + const struct dmi_device *dmi; + struct dmi_dev_onboard *donboard; + int domain_nr; + int bus; + int devfn; + + domain_nr = pci_domain_nr(pdev->bus); + bus = pdev->bus->number; + devfn = pdev->devfn; + + dmi = NULL; + while ((dmi = dmi_find_device(DMI_DEV_TYPE_DEV_ONBOARD, + NULL, dmi)) != NULL) { + donboard = dmi->device_data; + if (donboard && donboard->segment == domain_nr && + donboard->bus == bus && + donboard->devfn == devfn) { + if (buf) { + if (attribute == SMBIOS_ATTR_INSTANCE_SHOW) + return scnprintf(buf, PAGE_SIZE, + "%d\n", + donboard->instance); + else if (attribute == SMBIOS_ATTR_LABEL_SHOW) + return scnprintf(buf, PAGE_SIZE, + "%s\n", + dmi->name); + } + return strlen(dmi->name); + } + } + return 0; +} + +static umode_t smbios_instance_string_exist(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct device *dev; + struct pci_dev *pdev; + + dev = kobj_to_dev(kobj); + pdev = to_pci_dev(dev); + + return find_smbios_instance_string(pdev, NULL, SMBIOS_ATTR_NONE) ? + S_IRUGO : 0; +} + +static ssize_t smbioslabel_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct pci_dev *pdev; + pdev = to_pci_dev(dev); + + return find_smbios_instance_string(pdev, buf, + SMBIOS_ATTR_LABEL_SHOW); +} + +static ssize_t smbiosinstance_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct pci_dev *pdev; + pdev = to_pci_dev(dev); + + return find_smbios_instance_string(pdev, buf, + SMBIOS_ATTR_INSTANCE_SHOW); +} + +static struct device_attribute smbios_attr_label = { + .attr = {.name = "label", .mode = 0444}, + .show = smbioslabel_show, +}; + +static struct device_attribute smbios_attr_instance = { + .attr = {.name = "index", .mode = 0444}, + .show = smbiosinstance_show, +}; + +static struct attribute *smbios_attributes[] = { + &smbios_attr_label.attr, + &smbios_attr_instance.attr, + NULL, +}; + +static const struct attribute_group smbios_attr_group = { + .attrs = smbios_attributes, + .is_visible = smbios_instance_string_exist, +}; + +static int pci_create_smbiosname_file(struct pci_dev *pdev) +{ + return sysfs_create_group(&pdev->dev.kobj, &smbios_attr_group); +} + +static void pci_remove_smbiosname_file(struct pci_dev *pdev) +{ + sysfs_remove_group(&pdev->dev.kobj, &smbios_attr_group); +} +#else +static inline int pci_create_smbiosname_file(struct pci_dev *pdev) +{ + return -1; +} + +static inline void pci_remove_smbiosname_file(struct pci_dev *pdev) +{ +} +#endif + +#ifdef CONFIG_ACPI +enum acpi_attr_enum { + 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->buffer.pointer, + obj->buffer.length, + UTF16_LITTLE_ENDIAN, + buf, PAGE_SIZE - 1); + buf[len] = '\n'; +} + +static int dsm_get_label(struct device *dev, char *buf, + enum acpi_attr_enum attr) +{ + acpi_handle handle; + union acpi_object *obj, *tmp; + int len = -1; + + handle = ACPI_HANDLE(dev); + if (!handle) + return -1; + + obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, 0x2, + DEVICE_LABEL_DSM, NULL); + if (!obj) + return -1; + + tmp = obj->package.elements; + if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 2 && + tmp[0].type == ACPI_TYPE_INTEGER && + (tmp[1].type == ACPI_TYPE_STRING || + tmp[1].type == ACPI_TYPE_BUFFER)) { + /* + * The second string element is optional even when + * this _DSM is implemented; when not implemented, + * this entry must return a null string. + */ + if (attr == ACPI_ATTR_INDEX_SHOW) { + scnprintf(buf, PAGE_SIZE, "%llu\n", tmp->integer.value); + } else if (attr == ACPI_ATTR_LABEL_SHOW) { + if (tmp[1].type == ACPI_TYPE_STRING) + scnprintf(buf, PAGE_SIZE, "%s\n", + tmp[1].string.pointer); + else if (tmp[1].type == ACPI_TYPE_BUFFER) + dsm_label_utf16s_to_utf8s(tmp + 1, buf); + } + len = strlen(buf) > 0 ? strlen(buf) : -1; + } + + ACPI_FREE(obj); + + return len; +} + +static bool device_has_dsm(struct device *dev) +{ + acpi_handle handle; + + handle = ACPI_HANDLE(dev); + if (!handle) + return false; + + return !!acpi_check_dsm(handle, &pci_acpi_dsm_guid, 0x2, + 1 << DEVICE_LABEL_DSM); +} + +static umode_t acpi_index_string_exist(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct device *dev; + + dev = kobj_to_dev(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) +{ + return dsm_get_label(dev, buf, ACPI_ATTR_LABEL_SHOW); +} + +static ssize_t acpiindex_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return dsm_get_label(dev, buf, ACPI_ATTR_INDEX_SHOW); +} + +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 const 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; +} +#else +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; +} + +static inline bool device_has_dsm(struct device *dev) +{ + return false; +} +#endif + +void pci_create_firmware_label_files(struct pci_dev *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); +} -- cgit v1.2.3