2 * Copyright 2012 Intel Corporation
3 * Author: Josh Triplett <josh@joshtriplett.org>
5 * Based on the bgrt driver:
6 * Copyright 2012 Red Hat, Inc <mjg@redhat.com>
7 * Author: Matthew Garrett
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/acpi.h>
19 #include <linux/efi.h>
20 #include <linux/efi-bgrt.h>
22 struct acpi_table_bgrt bgrt_tab
;
23 size_t __initdata bgrt_image_size
;
30 static bool efi_bgrt_addr_valid(u64 addr
)
32 efi_memory_desc_t
*md
;
34 for_each_efi_memory_desc(md
) {
38 if (md
->type
!= EFI_BOOT_SERVICES_DATA
)
41 size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
42 end
= md
->phys_addr
+ size
;
43 if (addr
>= md
->phys_addr
&& addr
< end
)
50 void __init
efi_bgrt_init(struct acpi_table_header
*table
)
53 struct bmp_header bmp_header
;
54 struct acpi_table_bgrt
*bgrt
= &bgrt_tab
;
59 if (!efi_enabled(EFI_MEMMAP
))
62 if (table
->length
< sizeof(bgrt_tab
)) {
63 pr_notice("Ignoring BGRT: invalid length %u (expected %zu)\n",
64 table
->length
, sizeof(bgrt_tab
));
67 *bgrt
= *(struct acpi_table_bgrt
*)table
;
68 if (bgrt
->version
!= 1) {
69 pr_notice("Ignoring BGRT: invalid version %u (expected 1)\n",
73 if (bgrt
->status
& 0xfe) {
74 pr_notice("Ignoring BGRT: reserved status bits are non-zero %u\n",
78 if (bgrt
->image_type
!= 0) {
79 pr_notice("Ignoring BGRT: invalid image type %u (expected 0)\n",
83 if (!bgrt
->image_address
) {
84 pr_notice("Ignoring BGRT: null image address\n");
88 if (!efi_bgrt_addr_valid(bgrt
->image_address
)) {
89 pr_notice("Ignoring BGRT: invalid image address\n");
92 image
= early_memremap(bgrt
->image_address
, sizeof(bmp_header
));
94 pr_notice("Ignoring BGRT: failed to map image header memory\n");
98 memcpy(&bmp_header
, image
, sizeof(bmp_header
));
99 early_memunmap(image
, sizeof(bmp_header
));
100 if (bmp_header
.id
!= 0x4d42) {
101 pr_notice("Ignoring BGRT: Incorrect BMP magic number 0x%x (expected 0x4d42)\n",
105 bgrt_image_size
= bmp_header
.size
;
106 efi_mem_reserve(bgrt
->image_address
, bgrt_image_size
);
110 memset(bgrt
, 0, sizeof(bgrt_tab
));