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 <cpu_func.h>
13 #include <debug_uart.h>
14 #include <dm.h>
15 #include <errno.h>
16 #include <init.h>
17 #include <malloc.h>
18 #include <asm/global_data.h>
19 #include <linux/err.h>
20 #include <linux/types.h>
21 #include <efi.h>
22 #include <efi_api.h>
23 #include <sysreset.h>
24 
25 DECLARE_GLOBAL_DATA_PTR;
26 
27 static struct efi_priv *global_priv;
28 
efi_get_sys_table(void)29 struct efi_system_table *efi_get_sys_table(void)
30 {
31 	return global_priv->sys_table;
32 }
33 
efi_get_ram_base(void)34 unsigned long efi_get_ram_base(void)
35 {
36 	return global_priv->ram_base;
37 }
38 
setup_memory(struct efi_priv * priv)39 static efi_status_t setup_memory(struct efi_priv *priv)
40 {
41 	struct efi_boot_services *boot = priv->boot;
42 	efi_physical_addr_t addr;
43 	efi_status_t ret;
44 	int pages;
45 
46 	/*
47 	 * Use global_data_ptr instead of gd since it is an assignment. There
48 	 * are very few assignments to global_data in U-Boot and this makes
49 	 * it easier to find them.
50 	 */
51 	global_data_ptr = efi_malloc(priv, sizeof(struct global_data), &ret);
52 	if (!global_data_ptr)
53 		return ret;
54 	memset(gd, '\0', sizeof(*gd));
55 
56 	gd->malloc_base = (ulong)efi_malloc(priv, CONFIG_VAL(SYS_MALLOC_F_LEN),
57 					    &ret);
58 	if (!gd->malloc_base)
59 		return ret;
60 	pages = CONFIG_EFI_RAM_SIZE >> 12;
61 
62 	/*
63 	 * Don't allocate any memory above 4GB. U-Boot is a 32-bit application
64 	 * so we want it to load below 4GB.
65 	 */
66 	addr = 1ULL << 32;
67 	ret = boot->allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
68 				   priv->image_data_type, pages, &addr);
69 	if (ret) {
70 		printf("(using pool %lx) ", ret);
71 		priv->ram_base = (ulong)efi_malloc(priv, CONFIG_EFI_RAM_SIZE,
72 						   &ret);
73 		if (!priv->ram_base)
74 			return ret;
75 		priv->use_pool_for_malloc = true;
76 	} else {
77 		priv->ram_base = addr;
78 	}
79 	gd->ram_size = pages << 12;
80 
81 	return 0;
82 }
83 
free_memory(struct efi_priv * priv)84 static void free_memory(struct efi_priv *priv)
85 {
86 	struct efi_boot_services *boot = priv->boot;
87 
88 	if (priv->use_pool_for_malloc)
89 		efi_free(priv, (void *)priv->ram_base);
90 	else
91 		boot->free_pages(priv->ram_base, gd->ram_size >> 12);
92 
93 	efi_free(priv, (void *)gd->malloc_base);
94 	efi_free(priv, gd);
95 	global_data_ptr = NULL;
96 }
97 
98 /**
99  * efi_main() - Start an EFI image
100  *
101  * This function is called by our EFI start-up code. It handles running
102  * U-Boot. If it returns, EFI will continue. Another way to get back to EFI
103  * is via reset_cpu().
104  */
efi_main(efi_handle_t image,struct efi_system_table * sys_table)105 efi_status_t EFIAPI efi_main(efi_handle_t image,
106 			     struct efi_system_table *sys_table)
107 {
108 	struct efi_priv local_priv, *priv = &local_priv;
109 	efi_status_t ret;
110 
111 	/* Set up access to EFI data structures */
112 	efi_init(priv, "App", image, sys_table);
113 
114 	global_priv = priv;
115 
116 	/*
117 	 * Set up the EFI debug UART so that printf() works. This is
118 	 * implemented in the EFI serial driver, serial_efi.c. The application
119 	 * can use printf() freely.
120 	 */
121 	debug_uart_init();
122 
123 	ret = setup_memory(priv);
124 	if (ret) {
125 		printf("Failed to set up memory: ret=%lx\n", ret);
126 		return ret;
127 	}
128 
129 	printf("starting\n");
130 
131 	board_init_f(GD_FLG_SKIP_RELOC);
132 	board_init_r(NULL, 0);
133 	free_memory(priv);
134 
135 	return EFI_SUCCESS;
136 }
137 
efi_exit(void)138 static void efi_exit(void)
139 {
140 	struct efi_priv *priv = global_priv;
141 
142 	free_memory(priv);
143 	printf("U-Boot EFI exiting\n");
144 	priv->boot->exit(priv->parent_image, EFI_SUCCESS, 0, NULL);
145 }
146 
efi_sysreset_request(struct udevice * dev,enum sysreset_t type)147 static int efi_sysreset_request(struct udevice *dev, enum sysreset_t type)
148 {
149 	efi_exit();
150 
151 	return -EINPROGRESS;
152 }
153 
154 static const struct udevice_id efi_sysreset_ids[] = {
155 	{ .compatible = "efi,reset" },
156 	{ }
157 };
158 
159 static struct sysreset_ops efi_sysreset_ops = {
160 	.request = efi_sysreset_request,
161 };
162 
163 U_BOOT_DRIVER(efi_sysreset) = {
164 	.name = "efi-sysreset",
165 	.id = UCLASS_SYSRESET,
166 	.of_match = efi_sysreset_ids,
167 	.ops = &efi_sysreset_ops,
168 };
169