xref: /openbmc/u-boot/lib/efi/efi_app.c (revision 90c08fa0)
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 <errno.h>
14 #include <linux/err.h>
15 #include <linux/types.h>
16 #include <efi.h>
17 #include <efi_api.h>
18 
19 DECLARE_GLOBAL_DATA_PTR;
20 
21 static struct efi_priv *global_priv;
22 
23 struct efi_system_table *efi_get_sys_table(void)
24 {
25 	return global_priv->sys_table;
26 }
27 
28 unsigned long efi_get_ram_base(void)
29 {
30 	return global_priv->ram_base;
31 }
32 
33 static efi_status_t setup_memory(struct efi_priv *priv)
34 {
35 	struct efi_boot_services *boot = priv->boot;
36 	efi_physical_addr_t addr;
37 	efi_status_t ret;
38 	int pages;
39 
40 	/*
41 	 * Use global_data_ptr instead of gd since it is an assignment. There
42 	 * are very few assignments to global_data in U-Boot and this makes
43 	 * it easier to find them.
44 	 */
45 	global_data_ptr = efi_malloc(priv, sizeof(struct global_data), &ret);
46 	if (!global_data_ptr)
47 		return ret;
48 	memset(gd, '\0', sizeof(*gd));
49 
50 	gd->malloc_base = (ulong)efi_malloc(priv, CONFIG_VAL(SYS_MALLOC_F_LEN),
51 					    &ret);
52 	if (!gd->malloc_base)
53 		return ret;
54 	pages = CONFIG_EFI_RAM_SIZE >> 12;
55 
56 	/*
57 	 * Don't allocate any memory above 4GB. U-Boot is a 32-bit application
58 	 * so we want it to load below 4GB.
59 	 */
60 	addr = 1ULL << 32;
61 	ret = boot->allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
62 				   priv->image_data_type, pages, &addr);
63 	if (ret) {
64 		printf("(using pool %lx) ", ret);
65 		priv->ram_base = (ulong)efi_malloc(priv, CONFIG_EFI_RAM_SIZE,
66 						   &ret);
67 		if (!priv->ram_base)
68 			return ret;
69 		priv->use_pool_for_malloc = true;
70 	} else {
71 		priv->ram_base = addr;
72 	}
73 	gd->ram_size = pages << 12;
74 
75 	return 0;
76 }
77 
78 static void free_memory(struct efi_priv *priv)
79 {
80 	struct efi_boot_services *boot = priv->boot;
81 
82 	if (priv->use_pool_for_malloc)
83 		efi_free(priv, (void *)priv->ram_base);
84 	else
85 		boot->free_pages(priv->ram_base, gd->ram_size >> 12);
86 
87 	efi_free(priv, (void *)gd->malloc_base);
88 	efi_free(priv, gd);
89 	global_data_ptr = NULL;
90 }
91 
92 /**
93  * efi_main() - Start an EFI image
94  *
95  * This function is called by our EFI start-up code. It handles running
96  * U-Boot. If it returns, EFI will continue. Another way to get back to EFI
97  * is via reset_cpu().
98  */
99 efi_status_t EFIAPI efi_main(efi_handle_t image,
100 			     struct efi_system_table *sys_table)
101 {
102 	struct efi_priv local_priv, *priv = &local_priv;
103 	efi_status_t ret;
104 
105 	/* Set up access to EFI data structures */
106 	efi_init(priv, "App", image, sys_table);
107 
108 	global_priv = priv;
109 
110 	/*
111 	 * Set up the EFI debug UART so that printf() works. This is
112 	 * implemented in the EFI serial driver, serial_efi.c. The application
113 	 * can use printf() freely.
114 	 */
115 	debug_uart_init();
116 
117 	ret = setup_memory(priv);
118 	if (ret) {
119 		printf("Failed to set up memory: ret=%lx\n", ret);
120 		return ret;
121 	}
122 
123 	printf("starting\n");
124 
125 	board_init_f(GD_FLG_SKIP_RELOC);
126 	board_init_r(NULL, 0);
127 	free_memory(priv);
128 
129 	return EFI_SUCCESS;
130 }
131 
132 void reset_cpu(ulong addr)
133 {
134 	struct efi_priv *priv = global_priv;
135 
136 	free_memory(priv);
137 	printf("U-Boot EFI exiting\n");
138 	priv->boot->exit(priv->parent_image, EFI_SUCCESS, 0, NULL);
139 }
140