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 <cpu_func.h>
12 #include <debug_uart.h>
13 #include <dm.h>
14 #include <efi.h>
15 #include <efi_api.h>
16 #include <errno.h>
17 #include <init.h>
18 #include <malloc.h>
19 #include <sysreset.h>
20 #include <u-boot/uuid.h>
21 #include <asm/global_data.h>
22 #include <linux/err.h>
23 #include <linux/types.h>
24 #include <asm/global_data.h>
25 #include <dm/device-internal.h>
26 #include <dm/lists.h>
27 #include <dm/root.h>
28 #include <mapmem.h>
29 
30 DECLARE_GLOBAL_DATA_PTR;
31 
efi_info_get(enum efi_entry_t type,void ** datap,int * sizep)32 int efi_info_get(enum efi_entry_t type, void **datap, int *sizep)
33 {
34 	return -ENOSYS;
35 }
36 
efi_get_mmap(struct efi_mem_desc ** descp,int * sizep,uint * keyp,int * desc_sizep,uint * versionp)37 int efi_get_mmap(struct efi_mem_desc **descp, int *sizep, uint *keyp,
38 		 int *desc_sizep, uint *versionp)
39 {
40 	struct efi_priv *priv = efi_get_priv();
41 	struct efi_boot_services *boot = priv->sys_table->boottime;
42 	efi_uintn_t size, desc_size, key;
43 	struct efi_mem_desc *desc;
44 	efi_status_t ret;
45 	u32 version;
46 
47 	/* Get the memory map so we can switch off EFI */
48 	size = 0;
49 	ret = boot->get_memory_map(&size, NULL, &key, &desc_size, &version);
50 	if (ret != EFI_BUFFER_TOO_SMALL)
51 		return log_msg_ret("get", -ENOMEM);
52 
53 	desc = malloc(size);
54 	if (!desc)
55 		return log_msg_ret("mem", -ENOMEM);
56 
57 	ret = boot->get_memory_map(&size, desc, &key, &desc_size, &version);
58 	if (ret)
59 		return log_msg_ret("get", -EINVAL);
60 
61 	*descp = desc;
62 	*sizep = size;
63 	*desc_sizep = desc_size;
64 	*versionp = version;
65 	*keyp = key;
66 
67 	return 0;
68 }
69 
setup_memory(struct efi_priv * priv)70 static efi_status_t setup_memory(struct efi_priv *priv)
71 {
72 	struct efi_boot_services *boot = priv->boot;
73 	efi_physical_addr_t addr;
74 	efi_status_t ret;
75 	int pages;
76 
77 	/*
78 	 * Use global_data_ptr instead of gd since it is an assignment. There
79 	 * are very few assignments to global_data in U-Boot and this makes
80 	 * it easier to find them.
81 	 */
82 	global_data_ptr = efi_malloc(priv, sizeof(struct global_data), &ret);
83 	if (!global_data_ptr)
84 		return ret;
85 	memset(gd, '\0', sizeof(*gd));
86 
87 	gd->malloc_base = (ulong)efi_malloc(priv, CONFIG_VAL(SYS_MALLOC_F_LEN),
88 					    &ret);
89 	if (!gd->malloc_base)
90 		return ret;
91 	pages = CONFIG_EFI_RAM_SIZE >> 12;
92 
93 	/*
94 	 * Don't allocate any memory above 4GB. U-Boot is a 32-bit application
95 	 * so we want it to load below 4GB.
96 	 */
97 	addr = 1ULL << 32;
98 	ret = boot->allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
99 				   priv->image_data_type, pages, &addr);
100 	if (ret) {
101 		log_info("(using pool %lx) ", ret);
102 		priv->ram_base = (ulong)efi_malloc(priv, CONFIG_EFI_RAM_SIZE,
103 						   &ret);
104 		if (!priv->ram_base)
105 			return ret;
106 		priv->use_pool_for_malloc = true;
107 	} else {
108 		log_info("(using allocated RAM address %lx) ", (ulong)addr);
109 		priv->ram_base = addr;
110 	}
111 	gd->ram_size = pages << 12;
112 
113 	return 0;
114 }
115 
116 /**
117  * free_memory() - Free memory used by the U-Boot app
118  *
119  * This frees memory allocated in setup_memory(), in preparation for returning
120  * to UEFI. It also zeroes the global_data pointer.
121  *
122  * @priv: Private EFI data
123  */
free_memory(struct efi_priv * priv)124 static void free_memory(struct efi_priv *priv)
125 {
126 	struct efi_boot_services *boot = priv->boot;
127 
128 	if (priv->use_pool_for_malloc)
129 		efi_free(priv, (void *)priv->ram_base);
130 	else
131 		boot->free_pages(priv->ram_base, gd->ram_size >> 12);
132 
133 	efi_free(priv, (void *)gd->malloc_base);
134 	efi_free(priv, gd);
135 	global_data_ptr = NULL;
136 }
137 
scan_tables(struct efi_system_table * sys_table)138 static void scan_tables(struct efi_system_table *sys_table)
139 {
140 	efi_guid_t acpi = EFI_ACPI_TABLE_GUID;
141 	uint i;
142 
143 	for (i = 0; i < sys_table->nr_tables; i++) {
144 		struct efi_configuration_table *tab = &sys_table->tables[i];
145 
146 		if (!memcmp(&tab->guid, &acpi, sizeof(efi_guid_t)))
147 			gd_set_acpi_start(map_to_sysmem(tab->table));
148 	}
149 }
150 
151 /**
152  * efi_main() - Start an EFI image
153  *
154  * This function is called by our EFI start-up code. It handles running
155  * U-Boot. If it returns, EFI will continue. Another way to get back to EFI
156  * is via reset_cpu().
157  */
efi_main(efi_handle_t image,struct efi_system_table * sys_table)158 efi_status_t EFIAPI efi_main(efi_handle_t image,
159 			     struct efi_system_table *sys_table)
160 {
161 	struct efi_priv local_priv, *priv = &local_priv;
162 	efi_status_t ret;
163 
164 	/* Set up access to EFI data structures */
165 	ret = efi_init(priv, "App", image, sys_table);
166 	if (ret) {
167 		printf("Failed to set up U-Boot: err=%lx\n", ret);
168 		return ret;
169 	}
170 	efi_set_priv(priv);
171 
172 	/*
173 	 * Set up the EFI debug UART so that printf() works. This is
174 	 * implemented in the EFI serial driver, serial_efi.c. The application
175 	 * can use printf() freely.
176 	 */
177 	debug_uart_init();
178 
179 	ret = setup_memory(priv);
180 	if (ret) {
181 		printf("Failed to set up memory: ret=%lx\n", ret);
182 		return ret;
183 	}
184 
185 	scan_tables(priv->sys_table);
186 
187 	/*
188 	 * We could store the EFI memory map here, but it changes all the time,
189 	 * so this is only useful for debugging.
190 	 *
191 	 * ret = efi_store_memory_map(priv);
192 	 * if (ret)
193 	 *	return ret;
194 	 */
195 
196 	printf("starting\n");
197 
198 	board_init_f(GD_FLG_SKIP_RELOC);
199 	board_init_r(NULL, 0);
200 	free_memory(priv);
201 
202 	return EFI_SUCCESS;
203 }
204 
efi_exit(void)205 static void efi_exit(void)
206 {
207 	struct efi_priv *priv = efi_get_priv();
208 
209 	free_memory(priv);
210 	printf("U-Boot EFI exiting\n");
211 	priv->boot->exit(priv->parent_image, EFI_SUCCESS, 0, NULL);
212 }
213 
efi_sysreset_request(struct udevice * dev,enum sysreset_t type)214 static int efi_sysreset_request(struct udevice *dev, enum sysreset_t type)
215 {
216 	efi_exit();
217 
218 	return -EINPROGRESS;
219 }
220 
221 static const struct udevice_id efi_sysreset_ids[] = {
222 	{ .compatible = "efi,reset" },
223 	{ }
224 };
225 
226 static struct sysreset_ops efi_sysreset_ops = {
227 	.request = efi_sysreset_request,
228 };
229 
230 U_BOOT_DRIVER(efi_sysreset) = {
231 	.name = "efi-sysreset",
232 	.id = UCLASS_SYSRESET,
233 	.of_match = efi_sysreset_ids,
234 	.ops = &efi_sysreset_ops,
235 };
236