xref: /openbmc/u-boot/lib/efi/efi_app.c (revision da4cfa6b)
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  * This file implements U-Boot running as an EFI application.
9  */
10 
11 #include <common.h>
12 #include <debug_uart.h>
13 #include <dm.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 #include <sysreset.h>
20 
21 DECLARE_GLOBAL_DATA_PTR;
22 
23 static struct efi_priv *global_priv;
24 
25 struct efi_system_table *efi_get_sys_table(void)
26 {
27 	return global_priv->sys_table;
28 }
29 
30 unsigned long efi_get_ram_base(void)
31 {
32 	return global_priv->ram_base;
33 }
34 
35 static efi_status_t setup_memory(struct efi_priv *priv)
36 {
37 	struct efi_boot_services *boot = priv->boot;
38 	efi_physical_addr_t addr;
39 	efi_status_t ret;
40 	int pages;
41 
42 	/*
43 	 * Use global_data_ptr instead of gd since it is an assignment. There
44 	 * are very few assignments to global_data in U-Boot and this makes
45 	 * it easier to find them.
46 	 */
47 	global_data_ptr = efi_malloc(priv, sizeof(struct global_data), &ret);
48 	if (!global_data_ptr)
49 		return ret;
50 	memset(gd, '\0', sizeof(*gd));
51 
52 	gd->malloc_base = (ulong)efi_malloc(priv, CONFIG_VAL(SYS_MALLOC_F_LEN),
53 					    &ret);
54 	if (!gd->malloc_base)
55 		return ret;
56 	pages = CONFIG_EFI_RAM_SIZE >> 12;
57 
58 	/*
59 	 * Don't allocate any memory above 4GB. U-Boot is a 32-bit application
60 	 * so we want it to load below 4GB.
61 	 */
62 	addr = 1ULL << 32;
63 	ret = boot->allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
64 				   priv->image_data_type, pages, &addr);
65 	if (ret) {
66 		printf("(using pool %lx) ", ret);
67 		priv->ram_base = (ulong)efi_malloc(priv, CONFIG_EFI_RAM_SIZE,
68 						   &ret);
69 		if (!priv->ram_base)
70 			return ret;
71 		priv->use_pool_for_malloc = true;
72 	} else {
73 		priv->ram_base = addr;
74 	}
75 	gd->ram_size = pages << 12;
76 
77 	return 0;
78 }
79 
80 static void free_memory(struct efi_priv *priv)
81 {
82 	struct efi_boot_services *boot = priv->boot;
83 
84 	if (priv->use_pool_for_malloc)
85 		efi_free(priv, (void *)priv->ram_base);
86 	else
87 		boot->free_pages(priv->ram_base, gd->ram_size >> 12);
88 
89 	efi_free(priv, (void *)gd->malloc_base);
90 	efi_free(priv, gd);
91 	global_data_ptr = NULL;
92 }
93 
94 /**
95  * efi_main() - Start an EFI image
96  *
97  * This function is called by our EFI start-up code. It handles running
98  * U-Boot. If it returns, EFI will continue. Another way to get back to EFI
99  * is via reset_cpu().
100  */
101 efi_status_t EFIAPI efi_main(efi_handle_t image,
102 			     struct efi_system_table *sys_table)
103 {
104 	struct efi_priv local_priv, *priv = &local_priv;
105 	efi_status_t ret;
106 
107 	/* Set up access to EFI data structures */
108 	efi_init(priv, "App", image, sys_table);
109 
110 	global_priv = priv;
111 
112 	/*
113 	 * Set up the EFI debug UART so that printf() works. This is
114 	 * implemented in the EFI serial driver, serial_efi.c. The application
115 	 * can use printf() freely.
116 	 */
117 	debug_uart_init();
118 
119 	ret = setup_memory(priv);
120 	if (ret) {
121 		printf("Failed to set up memory: ret=%lx\n", ret);
122 		return ret;
123 	}
124 
125 	printf("starting\n");
126 
127 	board_init_f(GD_FLG_SKIP_RELOC);
128 	board_init_r(NULL, 0);
129 	free_memory(priv);
130 
131 	return EFI_SUCCESS;
132 }
133 
134 static void efi_exit(void)
135 {
136 	struct efi_priv *priv = global_priv;
137 
138 	free_memory(priv);
139 	printf("U-Boot EFI exiting\n");
140 	priv->boot->exit(priv->parent_image, EFI_SUCCESS, 0, NULL);
141 }
142 
143 static int efi_sysreset_request(struct udevice *dev, enum sysreset_t type)
144 {
145 	efi_exit();
146 
147 	return -EINPROGRESS;
148 }
149 
150 static const struct udevice_id efi_sysreset_ids[] = {
151 	{ .compatible = "efi,reset" },
152 	{ }
153 };
154 
155 static struct sysreset_ops efi_sysreset_ops = {
156 	.request = efi_sysreset_request,
157 };
158 
159 U_BOOT_DRIVER(efi_sysreset) = {
160 	.name = "efi-sysreset",
161 	.id = UCLASS_SYSRESET,
162 	.of_match = efi_sysreset_ids,
163 	.ops = &efi_sysreset_ops,
164 };
165