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 15 static void *bgrt_image; 16 static 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 26 BGRT_SHOW(version, version); 27 BGRT_SHOW(status, status); 28 BGRT_SHOW(type, image_type); 29 BGRT_SHOW(xoffset, image_offset_x); 30 BGRT_SHOW(yoffset, image_offset_y); 31 32 static BIN_ATTR_SIMPLE_RO(image); 33 34 static 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 43 static struct bin_attribute *bgrt_bin_attributes[] = { 44 &bin_attr_image, 45 NULL, 46 }; 47 48 static const struct attribute_group bgrt_attribute_group = { 49 .attrs = bgrt_attributes, 50 .bin_attrs = bgrt_bin_attributes, 51 }; 52 53 int __init acpi_parse_bgrt(struct acpi_table_header *table) 54 { 55 efi_bgrt_init(table); 56 return 0; 57 } 58 59 static int __init bgrt_init(void) 60 { 61 int ret; 62 63 if (!bgrt_tab.image_address) 64 return -ENODEV; 65 66 bgrt_image = memremap(bgrt_tab.image_address, bgrt_image_size, 67 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("bgrt", acpi_kobj); 77 if (!bgrt_kobj) { 78 ret = -EINVAL; 79 goto out_memmap; 80 } 81 82 ret = sysfs_create_group(bgrt_kobj, &bgrt_attribute_group); 83 if (ret) 84 goto out_kobject; 85 86 return 0; 87 88 out_kobject: 89 kobject_put(bgrt_kobj); 90 out_memmap: 91 memunmap(bgrt_image); 92 return ret; 93 } 94 device_initcall(bgrt_init); 95