xref: /openbmc/u-boot/lib/efi/efi.c (revision c882163b09b8a2c52e3dd8acd7d296d6d06d1f2e)
1  // SPDX-License-Identifier: GPL-2.0+
2  /*
3   * Copyright (c) 2015 Google, Inc
4   *
5   * EFI information obtained here:
6   * http://wiki.phoenix.com/wiki/index.php/EFI_BOOT_SERVICES
7   *
8   * Common EFI functions
9   */
10  
11  #include <common.h>
12  #include <debug_uart.h>
13  #include <errno.h>
14  #include <linux/err.h>
15  #include <linux/types.h>
16  #include <efi.h>
17  #include <efi_api.h>
18  
19  /*
20   * Unfortunately we cannot access any code outside what is built especially
21   * for the stub. lib/string.c is already being built for the U-Boot payload
22   * so it uses the wrong compiler flags. Add our own memset() here.
23   */
24  static void efi_memset(void *ptr, int ch, int size)
25  {
26  	char *dest = ptr;
27  
28  	while (size-- > 0)
29  		*dest++ = ch;
30  }
31  
32  /*
33   * Since the EFI stub cannot access most of the U-Boot code, add our own
34   * simple console output functions here. The EFI app will not use these since
35   * it can use the normal console.
36   */
37  void efi_putc(struct efi_priv *priv, const char ch)
38  {
39  	struct efi_simple_text_output_protocol *con = priv->sys_table->con_out;
40  	uint16_t ucode[2];
41  
42  	ucode[0] = ch;
43  	ucode[1] = '\0';
44  	con->output_string(con, ucode);
45  }
46  
47  void efi_puts(struct efi_priv *priv, const char *str)
48  {
49  	while (*str)
50  		efi_putc(priv, *str++);
51  }
52  
53  int efi_init(struct efi_priv *priv, const char *banner, efi_handle_t image,
54  	     struct efi_system_table *sys_table)
55  {
56  	efi_guid_t loaded_image_guid = LOADED_IMAGE_PROTOCOL_GUID;
57  	struct efi_boot_services *boot = sys_table->boottime;
58  	struct efi_loaded_image *loaded_image;
59  	int ret;
60  
61  	efi_memset(priv, '\0', sizeof(*priv));
62  	priv->sys_table = sys_table;
63  	priv->boot = sys_table->boottime;
64  	priv->parent_image = image;
65  	priv->run = sys_table->runtime;
66  
67  	efi_puts(priv, "U-Boot EFI ");
68  	efi_puts(priv, banner);
69  	efi_putc(priv, ' ');
70  
71  	ret = boot->open_protocol(priv->parent_image, &loaded_image_guid,
72  				  (void **)&loaded_image, priv->parent_image,
73  				  NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
74  	if (ret) {
75  		efi_puts(priv, "Failed to get loaded image protocol\n");
76  		return ret;
77  	}
78  	priv->image_data_type = loaded_image->image_data_type;
79  
80  	return 0;
81  }
82  
83  void *efi_malloc(struct efi_priv *priv, int size, efi_status_t *retp)
84  {
85  	struct efi_boot_services *boot = priv->boot;
86  	void *buf = NULL;
87  
88  	*retp = boot->allocate_pool(priv->image_data_type, size, &buf);
89  
90  	return buf;
91  }
92  
93  void efi_free(struct efi_priv *priv, void *ptr)
94  {
95  	struct efi_boot_services *boot = priv->boot;
96  
97  	boot->free_pool(ptr);
98  }
99