The optional type 15 entry of the DMI table describes a non-volatile storage-backed system event log.
In preparation for the next commit which exposes the raw bits of the event log to userland, create a new sub-directory within the dmi entry called "system_event_log" and expose attribute files that describe the event log itself. Currently, only a single child object is permitted within a dmi_sysfs_entry. We simply point at this child from the dmi_sysfs_entry if it exists. Signed-off-by: Mike Waychison <[email protected]> --- drivers/firmware/dmi-sysfs.c | 159 ++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 159 insertions(+), 0 deletions(-) diff --git a/drivers/firmware/dmi-sysfs.c b/drivers/firmware/dmi-sysfs.c index adcd604..3f49042 100644 --- a/drivers/firmware/dmi-sysfs.c +++ b/drivers/firmware/dmi-sysfs.c @@ -34,6 +34,7 @@ struct dmi_sysfs_entry { struct kobject kobj; int instance; struct list_head list; + struct kobject *child; }; /* @@ -76,6 +77,10 @@ struct dmi_sysfs_mapped_attribute dmi_sysfs_attr_##_entry##_##_name = { \ /************************************************* * Generic DMI entry support. *************************************************/ +static void dmi_entry_free(struct kobject *kobj) +{ + kfree(kobj); +} static struct dmi_sysfs_entry *to_entry(struct kobject *kobj) { @@ -179,6 +184,146 @@ static size_t dmi_entry_length(const struct dmi_header *dh) } /************************************************* + * Support bits for specialized DMI entry support + *************************************************/ +struct dmi_entry_attr_show_data { + struct attribute *attr; + char *buf; +}; + +static ssize_t dmi_entry_attr_show_helper(struct dmi_sysfs_entry *entry, + const struct dmi_header *dh, + void *_data) +{ + struct dmi_entry_attr_show_data *data = _data; + struct dmi_sysfs_mapped_attribute *attr; + + attr = container_of(data->attr, + struct dmi_sysfs_mapped_attribute, attr); + return attr->show(entry, dh, data->buf); +} + +static ssize_t dmi_entry_attr_show(struct kobject *kobj, + struct attribute *attr, + char *buf) +{ + struct dmi_entry_attr_show_data data = { + .attr = attr, + .buf = buf, + }; + /* Find the entry according to our parent and call the + * normalized show method hanging off of the attribute */ + return find_dmi_entry(to_entry(kobj->parent), + dmi_entry_attr_show_helper, &data); +} + +static const struct sysfs_ops dmi_sysfs_specialize_attr_ops = { + .show = dmi_entry_attr_show, +}; + +/************************************************* + * Specialized DMI entry support. + *************************************************/ + +/*** Type 15 - System Event Table ***/ + +#define DMI_SEL_ACCESS_METHOD_IO8 0x00 +#define DMI_SEL_ACCESS_METHOD_IO2x8 0x01 +#define DMI_SEL_ACCESS_METHOD_IO16 0x02 +#define DMI_SEL_ACCESS_METHOD_PHYS32 0x03 +#define DMI_SEL_ACCESS_METHOD_GPNV 0x04 + +struct dmi_system_event_log { + struct dmi_header header; + u16 area_length; + u16 header_start_offset; + u16 data_start_offset; + u8 access_method; + u8 status; + u32 change_token; + union { + struct { + u16 index_addr; + u16 data_addr; + } io; + u32 phys_addr32; + u16 gpnv_handle; + u32 access_method_address; + }; + u8 header_format; + u8 type_descriptors_supported_count; + u8 per_log_type_descriptor_length; + u8 supported_log_type_descriptos[0]; +} __packed; + +static const struct dmi_system_event_log *to_sel(const struct dmi_header *dh) +{ + return (const struct dmi_system_event_log *)dh; +} + +#define DMI_SYSFS_SEL_FIELD(_field) \ +static ssize_t dmi_sysfs_sel_##_field(struct dmi_sysfs_entry *entry, \ + const struct dmi_header *dh, \ + char *buf) \ +{ \ + const struct dmi_system_event_log *sel = to_sel(dh); \ + if (sizeof(*sel) > dmi_entry_length(dh)) \ + return -EIO; \ + return sprintf(buf, "%u\n", sel->_field); \ +} \ +static DMI_SYSFS_MAPPED_ATTR(sel, _field) + +DMI_SYSFS_SEL_FIELD(area_length); +DMI_SYSFS_SEL_FIELD(header_start_offset); +DMI_SYSFS_SEL_FIELD(data_start_offset); +DMI_SYSFS_SEL_FIELD(access_method); +DMI_SYSFS_SEL_FIELD(status); +DMI_SYSFS_SEL_FIELD(change_token); +DMI_SYSFS_SEL_FIELD(access_method_address); +DMI_SYSFS_SEL_FIELD(header_format); +DMI_SYSFS_SEL_FIELD(type_descriptors_supported_count); +DMI_SYSFS_SEL_FIELD(per_log_type_descriptor_length); + +static struct attribute *dmi_sysfs_sel_attrs[] = { + &dmi_sysfs_attr_sel_area_length.attr, + &dmi_sysfs_attr_sel_header_start_offset.attr, + &dmi_sysfs_attr_sel_data_start_offset.attr, + &dmi_sysfs_attr_sel_access_method.attr, + &dmi_sysfs_attr_sel_status.attr, + &dmi_sysfs_attr_sel_change_token.attr, + &dmi_sysfs_attr_sel_access_method_address.attr, + &dmi_sysfs_attr_sel_header_format.attr, + &dmi_sysfs_attr_sel_type_descriptors_supported_count.attr, + &dmi_sysfs_attr_sel_per_log_type_descriptor_length.attr, + NULL, +}; + + +static struct kobj_type dmi_system_event_log_ktype = { + .release = dmi_entry_free, + .sysfs_ops = &dmi_sysfs_specialize_attr_ops, + .default_attrs = dmi_sysfs_sel_attrs, +}; + +static int dmi_system_event_log(struct dmi_sysfs_entry *entry) +{ + int ret; + + entry->child = kzalloc(sizeof(*entry->child), GFP_KERNEL); + if (!entry->child) + return -ENOMEM; + ret = kobject_init_and_add(entry->child, + &dmi_system_event_log_ktype, + &entry->kobj, + "system_event_log"); + if (ret) + goto out_free; +out_free: + kfree(entry->child); + return ret; +} + +/************************************************* * Generic DMI entry support. *************************************************/ @@ -291,6 +436,18 @@ static void __init dmi_sysfs_register_handle(const struct dmi_header *dh, list_add_tail(&entry->list, &entry_list); spin_unlock(&entry_list_lock); + /* Handle specializations by type */ + switch (dh->type) { + case DMI_ENTRY_SYSTEM_EVENT_LOG: + *ret = dmi_system_event_log(entry); + break; + default: + /* No specialization */ + break; + } + if (*ret) + goto out_err; + /* Create the raw binary file to access the entry */ *ret = sysfs_create_bin_file(&entry->kobj, &dmi_entry_raw_attr); if (*ret) @@ -298,6 +455,7 @@ static void __init dmi_sysfs_register_handle(const struct dmi_header *dh, return; out_err: + kobject_put(entry->child); kobject_put(&entry->kobj); return; } @@ -308,6 +466,7 @@ static void cleanup_entry_list(void) /* No locks, we are on our way out */ list_for_each_entry_safe(entry, next, &entry_list, list) { + kobject_put(entry->child); kobject_put(&entry->kobj); } } -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
