xref: /openbmc/u-boot/lib/efi/efi.c (revision 2a0b7dc3)
1 /*
2  * Copyright (c) 2015 Google, Inc
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  *
6  * EFI information obtained here:
7  * http://wiki.phoenix.com/wiki/index.php/EFI_BOOT_SERVICES
8  *
9  * Common EFI functions
10  */
11 
12 #include <common.h>
13 #include <debug_uart.h>
14 #include <errno.h>
15 #include <linux/err.h>
16 #include <linux/types.h>
17 #include <efi.h>
18 #include <efi_api.h>
19 
20 DECLARE_GLOBAL_DATA_PTR;
21 
22 /*
23  * Unfortunately we cannot access any code outside what is built especially
24  * for the stub. lib/string.c is already being built for the U-Boot payload
25  * so it uses the wrong compiler flags. Add our own memset() here.
26  */
27 static void efi_memset(void *ptr, int ch, int size)
28 {
29 	char *dest = ptr;
30 
31 	while (size-- > 0)
32 		*dest++ = ch;
33 }
34 
35 /*
36  * Since the EFI stub cannot access most of the U-Boot code, add our own
37  * simple console output functions here. The EFI app will not use these since
38  * it can use the normal console.
39  */
40 void efi_putc(struct efi_priv *priv, const char ch)
41 {
42 	struct efi_simple_text_output_protocol *con = priv->sys_table->con_out;
43 	uint16_t ucode[2];
44 
45 	ucode[0] = ch;
46 	ucode[1] = '\0';
47 	con->output_string(con, ucode);
48 }
49 
50 void efi_puts(struct efi_priv *priv, const char *str)
51 {
52 	while (*str)
53 		efi_putc(priv, *str++);
54 }
55 
56 int efi_init(struct efi_priv *priv, const char *banner, efi_handle_t image,
57 	     struct efi_system_table *sys_table)
58 {
59 	efi_guid_t loaded_image_guid = LOADED_IMAGE_PROTOCOL_GUID;
60 	struct efi_boot_services *boot = sys_table->boottime;
61 	struct efi_loaded_image *loaded_image;
62 	int ret;
63 
64 	efi_memset(priv, '\0', sizeof(*priv));
65 	priv->sys_table = sys_table;
66 	priv->boot = sys_table->boottime;
67 	priv->parent_image = image;
68 	priv->run = sys_table->runtime;
69 
70 	efi_puts(priv, "U-Boot EFI ");
71 	efi_puts(priv, banner);
72 	efi_putc(priv, ' ');
73 
74 	ret = boot->open_protocol(priv->parent_image, &loaded_image_guid,
75 				  (void **)&loaded_image, &priv->parent_image,
76 				  NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
77 	if (ret) {
78 		efi_puts(priv, "Failed to get loaded image protocol\n");
79 		return ret;
80 	}
81 	priv->image_data_type = loaded_image->image_data_type;
82 
83 	return 0;
84 }
85 
86 void *efi_malloc(struct efi_priv *priv, int size, efi_status_t *retp)
87 {
88 	struct efi_boot_services *boot = priv->boot;
89 	void *buf = NULL;
90 
91 	*retp = boot->allocate_pool(priv->image_data_type, size, &buf);
92 
93 	return buf;
94 }
95 
96 void efi_free(struct efi_priv *priv, void *ptr)
97 {
98 	struct efi_boot_services *boot = priv->boot;
99 
100 	boot->free_pool(ptr);
101 }
102