PCI: export SMBIOS provided firmware instance and label to sysfs
Narendra K [Mon, 26 Jul 2010 10:56:50 +0000 (05:56 -0500)]
This patch exports SMBIOS provided firmware instance and label of
onboard PCI devices to sysfs.  New files 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.

Signed-off-by: Jordan Hargrave <jordan_hargrave@dell.com>
Signed-off-by: Narendra K <narendra_k@dell.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

Documentation/ABI/testing/sysfs-bus-pci
drivers/firmware/dmi_scan.c
drivers/pci/Makefile
drivers/pci/pci-label.c [new file with mode: 0644]
drivers/pci/pci-sysfs.c
drivers/pci/pci.h
include/linux/dmi.h

index 25be325..f979d82 100644 (file)
@@ -139,3 +139,30 @@ Contact:   linux-pci@vger.kernel.org
 Description:
                This symbolic link points to the PCI hotplug controller driver
                module that manages the hotplug slot.
+
+What:          /sys/bus/pci/devices/.../label
+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.
+Users:
+               Userspace applications interested in knowing the
+               firmware assigned name of the PCI device.
+
+What:          /sys/bus/pci/devices/.../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(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.
+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.
index d464672..b3d22d6 100644 (file)
@@ -277,6 +277,29 @@ static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
        list_add_tail(&dev->list, &dmi_devices);
 }
 
+static void __init dmi_save_dev_onboard(int instance, int segment, int bus,
+                                       int devfn, const char *name)
+{
+       struct dmi_dev_onboard *onboard_dev;
+
+       onboard_dev = dmi_alloc(sizeof(*onboard_dev) + strlen(name) + 1);
+       if (!onboard_dev) {
+               printk(KERN_ERR "dmi_save_dev_onboard: out of memory.\n");
+               return;
+       }
+       onboard_dev->instance = instance;
+       onboard_dev->segment = segment;
+       onboard_dev->bus = bus;
+       onboard_dev->devfn = devfn;
+
+       strcpy((char *)&onboard_dev[1], name);
+       onboard_dev->dev.type = DMI_DEV_TYPE_DEV_ONBOARD;
+       onboard_dev->dev.name = (char *)&onboard_dev[1];
+       onboard_dev->dev.device_data = onboard_dev;
+
+       list_add(&onboard_dev->dev.list, &dmi_devices);
+}
+
 static void __init dmi_save_extended_devices(const struct dmi_header *dm)
 {
        const u8 *d = (u8*) dm + 5;
@@ -285,6 +308,8 @@ static void __init dmi_save_extended_devices(const struct dmi_header *dm)
        if ((*d & 0x80) == 0)
                return;
 
+       dmi_save_dev_onboard(*(d+1), *(u16 *)(d+2), *(d+4), *(d+5),
+                            dmi_string_nosave(dm, *(d-1)));
        dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d - 1)));
 }
 
index 0b51857..dc1aa09 100644 (file)
@@ -55,6 +55,9 @@ obj-$(CONFIG_MICROBLAZE) += setup-bus.o
 #
 obj-$(CONFIG_ACPI)    += pci-acpi.o
 
+# SMBIOS provided firmware instance and labels
+obj-$(CONFIG_DMI)    += pci-label.o
+
 # Cardbus & CompactPCI use setup-bus
 obj-$(CONFIG_HOTPLUG) += setup-bus.o
 
diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c
new file mode 100644 (file)
index 0000000..111500e
--- /dev/null
@@ -0,0 +1,143 @@
+/*
+ * Purpose: Export the firmware instance and label associated with
+ * a pci device to sysfs
+ * Copyright (C) 2010 Dell Inc.
+ * by Narendra K <Narendra_K@dell.com>,
+ * Jordan Hargrave <Jordan_Hargrave@dell.com>
+ *
+ * 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/wiki/index.php/Oss/libnetdevname for more
+ * information.
+ */
+
+#include <linux/dmi.h>
+#include <linux/sysfs.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include "pci.h"
+
+enum smbios_attr_enum {
+       SMBIOS_ATTR_NONE = 0,
+       SMBIOS_ATTR_LABEL_SHOW,
+       SMBIOS_ATTR_INSTANCE_SHOW,
+};
+
+static mode_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 bus;
+       int devfn;
+
+       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->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 mode_t
+smbios_instance_string_exist(struct kobject *kobj, struct attribute *attr,
+                            int n)
+{
+       struct device *dev;
+       struct pci_dev *pdev;
+
+       dev = container_of(kobj, struct device, 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, .owner = THIS_MODULE},
+       .show = smbioslabel_show,
+};
+
+static struct device_attribute smbios_attr_instance = {
+       .attr = {.name = "index", .mode = 0444, .owner = THIS_MODULE},
+       .show = smbiosinstance_show,
+};
+
+static struct attribute *smbios_attributes[] = {
+       &smbios_attr_label.attr,
+       &smbios_attr_instance.attr,
+       NULL,
+};
+
+static 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)
+{
+       if (!sysfs_create_group(&pdev->dev.kobj, &smbios_attr_group))
+               return 0;
+       return -ENODEV;
+}
+
+static void
+pci_remove_smbiosname_file(struct pci_dev *pdev)
+{
+       sysfs_remove_group(&pdev->dev.kobj, &smbios_attr_group);
+}
+
+void pci_create_firmware_label_files(struct pci_dev *pdev)
+{
+       if (!pci_create_smbiosname_file(pdev))
+               ;
+}
+
+void pci_remove_firmware_label_files(struct pci_dev *pdev)
+{
+       pci_remove_smbiosname_file(pdev);
+}
index f7692dc..b5a7d9b 100644 (file)
@@ -1165,6 +1165,8 @@ int __must_check pci_create_sysfs_dev_files (struct pci_dev *pdev)
        if (retval)
                goto err_vga_file;
 
+       pci_create_firmware_label_files(pdev);
+
        return 0;
 
 err_vga_file:
@@ -1232,6 +1234,9 @@ void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
                sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
                kfree(pdev->rom_attr);
        }
+
+       pci_remove_firmware_label_files(pdev);
+
 }
 
 static int __init pci_sysfs_init(void)
index f8077b3..d930338 100644 (file)
 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
+static inline void pci_create_firmware_label_files(struct pci_dev *pdev)
+{ return 0; }
+static inline void pci_remove_firmware_label_files(struct pci_dev *pdev)
+{ return 0; }
+#else
+extern void pci_create_firmware_label_files(struct pci_dev *pdev);
+extern void pci_remove_firmware_label_files(struct pci_dev *pdev);
+#endif
 extern void pci_cleanup_rom(struct pci_dev *dev);
 #ifdef HAVE_PCI_MMAP
 extern int pci_mmap_fits(struct pci_dev *pdev, int resno,
index a8a3e1a..90e087f 100644 (file)
@@ -20,6 +20,7 @@ enum dmi_device_type {
        DMI_DEV_TYPE_SAS,
        DMI_DEV_TYPE_IPMI = -1,
        DMI_DEV_TYPE_OEM_STRING = -2,
+       DMI_DEV_TYPE_DEV_ONBOARD = -3,
 };
 
 struct dmi_header {
@@ -37,6 +38,14 @@ struct dmi_device {
 
 #ifdef CONFIG_DMI
 
+struct dmi_dev_onboard {
+       struct dmi_device dev;
+       int instance;
+       int segment;
+       int bus;
+       int devfn;
+};
+
 extern int dmi_check_system(const struct dmi_system_id *list);
 const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list);
 extern const char * dmi_get_system_info(int field);