1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * BGRT boot graphic support
4 * Authors: Matthew Garrett, Josh Triplett <josh@joshtriplett.org>
5 * Copyright 2012 Red Hat, Inc <mjg@redhat.com>
6 * Copyright 2012 Intel Corporation
7 */
8
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/device.h>
12#include <linux/sysfs.h>
13#include <linux/efi-bgrt.h>
14
15static void *bgrt_image;
16static struct kobject *bgrt_kobj;
17
18#define BGRT_SHOW(_name, _member) \
19 static ssize_t _name##_show(struct kobject *kobj, \
20 struct kobj_attribute *attr, char *buf) \
21 { \
22 return sysfs_emit(buf, "%d\n", bgrt_tab._member); \
23 } \
24 static struct kobj_attribute bgrt_attr_##_name = __ATTR_RO(_name)
25
26BGRT_SHOW(version, version);
27BGRT_SHOW(status, status);
28BGRT_SHOW(type, image_type);
29BGRT_SHOW(xoffset, image_offset_x);
30BGRT_SHOW(yoffset, image_offset_y);
31
32static __ro_after_init BIN_ATTR_SIMPLE_RO(image);
33
34static struct attribute *bgrt_attributes[] = {
35 &bgrt_attr_version.attr,
36 &bgrt_attr_status.attr,
37 &bgrt_attr_type.attr,
38 &bgrt_attr_xoffset.attr,
39 &bgrt_attr_yoffset.attr,
40 NULL,
41};
42
43static const struct bin_attribute *const bgrt_bin_attributes[] = {
44 &bin_attr_image,
45 NULL,
46};
47
48static const struct attribute_group bgrt_attribute_group = {
49 .attrs = bgrt_attributes,
50 .bin_attrs = bgrt_bin_attributes,
51};
52
53int __init acpi_parse_bgrt(struct acpi_table_header *table)
54{
55 efi_bgrt_init(table);
56 return 0;
57}
58
59static int __init bgrt_init(void)
60{
61 int ret;
62
63 if (!bgrt_tab.image_address)
64 return -ENODEV;
65
66 bgrt_image = memremap(offset: bgrt_tab.image_address, size: bgrt_image_size,
67 flags: MEMREMAP_WB);
68 if (!bgrt_image) {
69 pr_notice("Ignoring BGRT: failed to map image memory\n");
70 return -ENOMEM;
71 }
72
73 bin_attr_image.private = bgrt_image;
74 bin_attr_image.size = bgrt_image_size;
75
76 bgrt_kobj = kobject_create_and_add(name: "bgrt", parent: acpi_kobj);
77 if (!bgrt_kobj) {
78 ret = -EINVAL;
79 goto out_memmap;
80 }
81
82 ret = sysfs_create_group(kobj: bgrt_kobj, grp: &bgrt_attribute_group);
83 if (ret)
84 goto out_kobject;
85
86 return 0;
87
88out_kobject:
89 kobject_put(kobj: bgrt_kobj);
90out_memmap:
91 memunmap(addr: bgrt_image);
92 return ret;
93}
94device_initcall(bgrt_init);
95