diff options
Diffstat (limited to 'drivers/pci/pci-label.c')
| -rw-r--r-- | drivers/pci/pci-label.c | 252 |
1 files changed, 246 insertions, 6 deletions
diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c index 90c0a729cd3..77cb2a14c89 100644 --- a/drivers/pci/pci-label.c +++ b/drivers/pci/pci-label.c @@ -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 +26,29 @@ #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_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 +148,7 @@ 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 +157,227 @@ 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; +} + +static inline bool +device_has_dsm(struct device *dev) +{ + return false; +} + +#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); } |