xref: /openbmc/u-boot/lib/efi/efi.c (revision 3ce88cd7)
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 /*
21  * Unfortunately we cannot access any code outside what is built especially
22  * for the stub. lib/string.c is already being built for the U-Boot payload
23  * so it uses the wrong compiler flags. Add our own memset() here.
24  */
25 static void efi_memset(void *ptr, int ch, int size)
26 {
27 	char *dest = ptr;
28 
29 	while (size-- > 0)
30 		*dest++ = ch;
31 }
32 
33 /*
34  * Since the EFI stub cannot access most of the U-Boot code, add our own
35  * simple console output functions here. The EFI app will not use these since
36  * it can use the normal console.
37  */
38 void efi_putc(struct efi_priv *priv, const char ch)
39 {
40 	struct efi_simple_text_output_protocol *con = priv->sys_table->con_out;
41 	uint16_t ucode[2];
42 
43 	ucode[0] = ch;
44 	ucode[1] = '\0';
45 	con->output_string(con, ucode);
46 }
47 
48 void efi_puts(struct efi_priv *priv, const char *str)
49 {
50 	while (*str)
51 		efi_putc(priv, *str++);
52 }
53 
54 int efi_init(struct efi_priv *priv, const char *banner, efi_handle_t image,
55 	     struct efi_system_table *sys_table)
56 {
57 	efi_guid_t loaded_image_guid = LOADED_IMAGE_PROTOCOL_GUID;
58 	struct efi_boot_services *boot = sys_table->boottime;
59 	struct efi_loaded_image *loaded_image;
60 	int ret;
61 
62 	efi_memset(priv, '\0', sizeof(*priv));
63 	priv->sys_table = sys_table;
64 	priv->boot = sys_table->boottime;
65 	priv->parent_image = image;
66 	priv->run = sys_table->runtime;
67 
68 	efi_puts(priv, "U-Boot EFI ");
69 	efi_puts(priv, banner);
70 	efi_putc(priv, ' ');
71 
72 	ret = boot->open_protocol(priv->parent_image, &loaded_image_guid,
73 				  (void **)&loaded_image, &priv->parent_image,
74 				  NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
75 	if (ret) {
76 		efi_puts(priv, "Failed to get loaded image protocol\n");
77 		return ret;
78 	}
79 	priv->image_data_type = loaded_image->image_data_type;
80 
81 	return 0;
82 }
83 
84 void *efi_malloc(struct efi_priv *priv, int size, efi_status_t *retp)
85 {
86 	struct efi_boot_services *boot = priv->boot;
87 	void *buf = NULL;
88 
89 	*retp = boot->allocate_pool(priv->image_data_type, size, &buf);
90 
91 	return buf;
92 }
93 
94 void efi_free(struct efi_priv *priv, void *ptr)
95 {
96 	struct efi_boot_services *boot = priv->boot;
97 
98 	boot->free_pool(ptr);
99 }
100