1 files changed, 143 insertions, 0 deletions

diff --git a/drivers/firmware/dmi-sysfs.c b/drivers/firmware/dmi-sysfs.c
index d20961011039..a5afd805e66f 100644
--- a/drivers/firmware/dmi-sysfs.c
+++ b/drivers/firmware/dmi-sysfs.c
@@ -312,6 +312,140 @@ static struct kobj_type dmi_system_event_log_ktype = {
 	.default_attrs = dmi_sysfs_sel_attrs,
 };
 
+typedef u8 (*sel_io_reader)(const struct dmi_system_event_log *sel,
+			    loff_t offset);
+
+static DEFINE_MUTEX(io_port_lock);
+
+static u8 read_sel_8bit_indexed_io(const struct dmi_system_event_log *sel,
+				   loff_t offset)
+{
+	u8 ret;
+
+	mutex_lock(&io_port_lock);
+	outb((u8)offset, sel->io.index_addr);
+	ret = inb(sel->io.data_addr);
+	mutex_unlock(&io_port_lock);
+	return ret;
+}
+
+static u8 read_sel_2x8bit_indexed_io(const struct dmi_system_event_log *sel,
+				     loff_t offset)
+{
+	u8 ret;
+
+	mutex_lock(&io_port_lock);
+	outb((u8)offset, sel->io.index_addr);
+	outb((u8)(offset >> 8), sel->io.index_addr + 1);
+	ret = inb(sel->io.data_addr);
+	mutex_unlock(&io_port_lock);
+	return ret;
+}
+
+static u8 read_sel_16bit_indexed_io(const struct dmi_system_event_log *sel,
+				    loff_t offset)
+{
+	u8 ret;
+
+	mutex_lock(&io_port_lock);
+	outw((u16)offset, sel->io.index_addr);
+	ret = inb(sel->io.data_addr);
+	mutex_unlock(&io_port_lock);
+	return ret;
+}
+
+static sel_io_reader sel_io_readers[] = {
+	[DMI_SEL_ACCESS_METHOD_IO8]	= read_sel_8bit_indexed_io,
+	[DMI_SEL_ACCESS_METHOD_IO2x8]	= read_sel_2x8bit_indexed_io,
+	[DMI_SEL_ACCESS_METHOD_IO16]	= read_sel_16bit_indexed_io,
+};
+
+static ssize_t dmi_sel_raw_read_io(struct dmi_sysfs_entry *entry,
+				   const struct dmi_system_event_log *sel,
+				   char *buf, loff_t pos, size_t count)
+{
+	ssize_t wrote = 0;
+
+	sel_io_reader io_reader = sel_io_readers[sel->access_method];
+
+	while (count && pos < sel->area_length) {
+		count--;
+		*(buf++) = io_reader(sel, pos++);
+		wrote++;
+	}
+
+	return wrote;
+}
+
+static ssize_t dmi_sel_raw_read_phys32(struct dmi_sysfs_entry *entry,
+				       const struct dmi_system_event_log *sel,
+				       char *buf, loff_t pos, size_t count)
+{
+	u8 __iomem *mapped;
+	ssize_t wrote = 0;
+
+	mapped = ioremap(sel->access_method_address, sel->area_length);
+	if (!mapped)
+		return -EIO;
+
+	while (count && pos < sel->area_length) {
+		count--;
+		*(buf++) = readb(mapped + pos++);
+		wrote++;
+	}
+
+	iounmap(mapped);
+	return wrote;
+}
+
+static ssize_t dmi_sel_raw_read_helper(struct dmi_sysfs_entry *entry,
+				       const struct dmi_header *dh,
+				       void *_state)
+{
+	struct dmi_read_state *state = _state;
+	const struct dmi_system_event_log *sel = to_sel(dh);
+
+	if (sizeof(*sel) > dmi_entry_length(dh))
+		return -EIO;
+
+	switch (sel->access_method) {
+	case DMI_SEL_ACCESS_METHOD_IO8:
+	case DMI_SEL_ACCESS_METHOD_IO2x8:
+	case DMI_SEL_ACCESS_METHOD_IO16:
+		return dmi_sel_raw_read_io(entry, sel, state->buf,
+					   state->pos, state->count);
+	case DMI_SEL_ACCESS_METHOD_PHYS32:
+		return dmi_sel_raw_read_phys32(entry, sel, state->buf,
+					       state->pos, state->count);
+	case DMI_SEL_ACCESS_METHOD_GPNV:
+		pr_info("dmi-sysfs: GPNV support missing.\n");
+		return -EIO;
+	default:
+		pr_info("dmi-sysfs: Unknown access method %02x\n",
+			sel->access_method);
+		return -EIO;
+	}
+}
+
+static ssize_t dmi_sel_raw_read(struct file *filp, struct kobject *kobj,
+				struct bin_attribute *bin_attr,
+				char *buf, loff_t pos, size_t count)
+{
+	struct dmi_sysfs_entry *entry = to_entry(kobj->parent);
+	struct dmi_read_state state = {
+		.buf = buf,
+		.pos = pos,
+		.count = count,
+	};
+
+	return find_dmi_entry(entry, dmi_sel_raw_read_helper, &state);
+}
+
+static struct bin_attribute dmi_sel_raw_attr = {
+	.attr = {.name = "raw_event_log", .mode = 0400},
+	.read = dmi_sel_raw_read,
+};
+
 static int dmi_system_event_log(struct dmi_sysfs_entry *entry)
 {
 	int ret;
@@ -325,6 +459,15 @@ static int dmi_system_event_log(struct dmi_sysfs_entry *entry)
 				   "system_event_log");
 	if (ret)
 		goto out_free;
+
+	ret = sysfs_create_bin_file(entry->child, &dmi_sel_raw_attr);
+	if (ret)
+		goto out_del;
+
+	return 0;
+
+out_del:
+	kobject_del(entry->child);
 out_free:
 	kfree(entry->child);
 	return ret;