1 // SPDX-License-Identifier: GPL-2.0-only
2
3 #include <linux/efi.h>
4 #include <linux/screen_info.h>
5
6 #include <asm/efi.h>
7
8 #include "efistub.h"
9
10 static unsigned long screen_info_offset;
11
alloc_screen_info(void)12 struct screen_info *alloc_screen_info(void)
13 {
14 if (IS_ENABLED(CONFIG_ARM))
15 return __alloc_screen_info();
16
17 if (IS_ENABLED(CONFIG_X86) ||
18 IS_ENABLED(CONFIG_EFI_EARLYCON) ||
19 IS_ENABLED(CONFIG_SYSFB))
20 return (void *)&screen_info + screen_info_offset;
21
22 return NULL;
23 }
24
25 /*
26 * EFI entry point for the generic EFI stub used by ARM, arm64, RISC-V and
27 * LoongArch. This is the entrypoint that is described in the PE/COFF header
28 * of the core kernel.
29 */
efi_pe_entry(efi_handle_t handle,efi_system_table_t * systab)30 efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
31 efi_system_table_t *systab)
32 {
33 efi_loaded_image_t *image;
34 efi_status_t status;
35 unsigned long image_addr;
36 unsigned long image_size = 0;
37 /* addr/point and size pairs for memory management*/
38 char *cmdline_ptr = NULL;
39 efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID;
40 unsigned long reserve_addr = 0;
41 unsigned long reserve_size = 0;
42
43 WRITE_ONCE(efi_system_table, systab);
44
45 /* Check if we were booted by the EFI firmware */
46 if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
47 return EFI_INVALID_PARAMETER;
48
49 /*
50 * Get a handle to the loaded image protocol. This is used to get
51 * information about the running image, such as size and the command
52 * line.
53 */
54 status = efi_bs_call(handle_protocol, handle, &loaded_image_proto,
55 (void *)&image);
56 if (status != EFI_SUCCESS) {
57 efi_err("Failed to get loaded image protocol\n");
58 return status;
59 }
60
61 status = efi_handle_cmdline(image, &cmdline_ptr);
62 if (status != EFI_SUCCESS)
63 return status;
64
65 efi_info("Booting Linux Kernel...\n");
66
67 status = handle_kernel_image(&image_addr, &image_size,
68 &reserve_addr,
69 &reserve_size,
70 image, handle);
71 if (status != EFI_SUCCESS) {
72 efi_err("Failed to relocate kernel\n");
73 return status;
74 }
75
76 screen_info_offset = image_addr - (unsigned long)image->image_base;
77
78 status = efi_stub_common(handle, image, image_addr, cmdline_ptr);
79
80 efi_free(image_size, image_addr);
81 efi_free(reserve_size, reserve_addr);
82
83 return status;
84 }
85