xref: /openbmc/u-boot/lib/efi/efi_app.c (revision 6b44ae6b)
1 /*
2  * Copyright (c) 2015 Google, Inc
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  *
6  * EFI information obtained here:
7  * http://wiki.phoenix.com/wiki/index.php/EFI_BOOT_SERVICES
8  *
9  * This file implements U-Boot running as an EFI application.
10  */
11 
12 #include <common.h>
13 #include <debug_uart.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 
20 DECLARE_GLOBAL_DATA_PTR;
21 
22 static struct efi_priv *global_priv;
23 
24 struct efi_system_table *efi_get_sys_table(void)
25 {
26 	return global_priv->sys_table;
27 }
28 
29 unsigned long efi_get_ram_base(void)
30 {
31 	return global_priv->ram_base;
32 }
33 
34 static efi_status_t setup_memory(struct efi_priv *priv)
35 {
36 	struct efi_boot_services *boot = priv->boot;
37 	efi_physical_addr_t addr;
38 	efi_status_t ret;
39 	int pages;
40 
41 	/*
42 	 * Use global_data_ptr instead of gd since it is an assignment. There
43 	 * are very few assignments to global_data in U-Boot and this makes
44 	 * it easier to find them.
45 	 */
46 	global_data_ptr = efi_malloc(priv, sizeof(struct global_data), &ret);
47 	if (!global_data_ptr)
48 		return ret;
49 	memset(gd, '\0', sizeof(*gd));
50 
51 	gd->malloc_base = (ulong)efi_malloc(priv, CONFIG_SYS_MALLOC_F_LEN,
52 					    &ret);
53 	if (!gd->malloc_base)
54 		return ret;
55 	pages = CONFIG_EFI_RAM_SIZE >> 12;
56 
57 	/*
58 	 * Don't allocate any memory above 4GB. U-Boot is a 32-bit application
59 	 * so we want it to load below 4GB.
60 	 */
61 	addr = 1ULL << 32;
62 	ret = boot->allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
63 				   priv->image_data_type, pages, &addr);
64 	if (ret) {
65 		printf("(using pool %lx) ", ret);
66 		priv->ram_base = (ulong)efi_malloc(priv, CONFIG_EFI_RAM_SIZE,
67 						   &ret);
68 		if (!priv->ram_base)
69 			return ret;
70 		priv->use_pool_for_malloc = true;
71 	} else {
72 		priv->ram_base = addr;
73 	}
74 	gd->ram_size = pages << 12;
75 
76 	return 0;
77 }
78 
79 static void free_memory(struct efi_priv *priv)
80 {
81 	struct efi_boot_services *boot = priv->boot;
82 
83 	if (priv->use_pool_for_malloc)
84 		efi_free(priv, (void *)priv->ram_base);
85 	else
86 		boot->free_pages(priv->ram_base, gd->ram_size >> 12);
87 
88 	efi_free(priv, (void *)gd->malloc_base);
89 	efi_free(priv, gd);
90 	global_data_ptr = NULL;
91 }
92 
93 /**
94  * efi_main() - Start an EFI image
95  *
96  * This function is called by our EFI start-up code. It handles running
97  * U-Boot. If it returns, EFI will continue. Another way to get back to EFI
98  * is via reset_cpu().
99  */
100 efi_status_t efi_main(efi_handle_t image, 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