2 * FDT related Helper functions used by the EFI stub on multiple
3 * architectures. This should be #included by the EFI stub
4 * implementation files.
6 * Copyright 2013 Linaro Limited; author Roy Franz
8 * This file is part of the Linux kernel, and is made available
9 * under the terms of the GNU General Public License version 2.
13 static efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
14 unsigned long orig_fdt_size,
15 void *fdt, int new_fdt_size, char *cmdline_ptr,
16 u64 initrd_addr, u64 initrd_size,
17 efi_memory_desc_t *memory_map,
18 unsigned long map_size, unsigned long desc_size,
26 /* Do some checks on provided FDT, if it exists*/
28 if (fdt_check_header(orig_fdt)) {
29 pr_efi_err(sys_table, "Device Tree header not valid!\n");
30 return EFI_LOAD_ERROR;
33 * We don't get the size of the FDT if we get if from a
34 * configuration table.
36 if (orig_fdt_size && fdt_totalsize(orig_fdt) > orig_fdt_size) {
37 pr_efi_err(sys_table, "Truncated device tree! foo!\n");
38 return EFI_LOAD_ERROR;
43 status = fdt_open_into(orig_fdt, fdt, new_fdt_size);
45 status = fdt_create_empty_tree(fdt, new_fdt_size);
51 * Delete any memory nodes present. We must delete nodes which
52 * early_init_dt_scan_memory may try to use.
59 node = fdt_next_node(fdt, prev, NULL);
63 type = fdt_getprop(fdt, node, "device_type", &len);
64 if (type && strncmp(type, "memory", len) == 0) {
65 fdt_del_node(fdt, node);
72 node = fdt_subnode_offset(fdt, 0, "chosen");
74 node = fdt_add_subnode(fdt, 0, "chosen");
76 status = node; /* node is error code when negative */
81 if ((cmdline_ptr != NULL) && (strlen(cmdline_ptr) > 0)) {
82 status = fdt_setprop(fdt, node, "bootargs", cmdline_ptr,
83 strlen(cmdline_ptr) + 1);
88 /* Set initrd address/end in device tree, if present */
89 if (initrd_size != 0) {
91 u64 initrd_image_start = cpu_to_fdt64(initrd_addr);
93 status = fdt_setprop(fdt, node, "linux,initrd-start",
94 &initrd_image_start, sizeof(u64));
97 initrd_image_end = cpu_to_fdt64(initrd_addr + initrd_size);
98 status = fdt_setprop(fdt, node, "linux,initrd-end",
99 &initrd_image_end, sizeof(u64));
104 /* Add FDT entries for EFI runtime services in chosen node. */
105 node = fdt_subnode_offset(fdt, 0, "chosen");
106 fdt_val64 = cpu_to_fdt64((u64)(unsigned long)sys_table);
107 status = fdt_setprop(fdt, node, "linux,uefi-system-table",
108 &fdt_val64, sizeof(fdt_val64));
112 fdt_val64 = cpu_to_fdt64((u64)(unsigned long)memory_map);
113 status = fdt_setprop(fdt, node, "linux,uefi-mmap-start",
114 &fdt_val64, sizeof(fdt_val64));
118 fdt_val32 = cpu_to_fdt32(map_size);
119 status = fdt_setprop(fdt, node, "linux,uefi-mmap-size",
120 &fdt_val32, sizeof(fdt_val32));
124 fdt_val32 = cpu_to_fdt32(desc_size);
125 status = fdt_setprop(fdt, node, "linux,uefi-mmap-desc-size",
126 &fdt_val32, sizeof(fdt_val32));
130 fdt_val32 = cpu_to_fdt32(desc_ver);
131 status = fdt_setprop(fdt, node, "linux,uefi-mmap-desc-ver",
132 &fdt_val32, sizeof(fdt_val32));
137 * Add kernel version banner so stub/kernel match can be
140 status = fdt_setprop_string(fdt, node, "linux,uefi-stub-kern-ver",
148 if (status == -FDT_ERR_NOSPACE)
149 return EFI_BUFFER_TOO_SMALL;
151 return EFI_LOAD_ERROR;
154 #ifndef EFI_FDT_ALIGN
155 #define EFI_FDT_ALIGN EFI_PAGE_SIZE
159 * Allocate memory for a new FDT, then add EFI, commandline, and
160 * initrd related fields to the FDT. This routine increases the
161 * FDT allocation size until the allocated memory is large
162 * enough. EFI allocations are in EFI_PAGE_SIZE granules,
163 * which are fixed at 4K bytes, so in most cases the first
164 * allocation should succeed.
165 * EFI boot services are exited at the end of this function.
166 * There must be no allocations between the get_memory_map()
167 * call and the exit_boot_services() call, so the exiting of
168 * boot services is very tightly tied to the creation of the FDT
169 * with the final memory map in it.
172 efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
174 unsigned long *new_fdt_addr,
175 unsigned long max_addr,
176 u64 initrd_addr, u64 initrd_size,
178 unsigned long fdt_addr,
179 unsigned long fdt_size)
181 unsigned long map_size, desc_size;
183 unsigned long mmap_key;
184 efi_memory_desc_t *memory_map;
185 unsigned long new_fdt_size;
189 * Estimate size of new FDT, and allocate memory for it. We
190 * will allocate a bigger buffer if this ends up being too
191 * small, so a rough guess is OK here.
193 new_fdt_size = fdt_size + EFI_PAGE_SIZE;
195 status = efi_high_alloc(sys_table, new_fdt_size, EFI_FDT_ALIGN,
196 new_fdt_addr, max_addr);
197 if (status != EFI_SUCCESS) {
198 pr_efi_err(sys_table, "Unable to allocate memory for new device tree.\n");
203 * Now that we have done our final memory allocation (and free)
204 * we can get the memory map key needed for
205 * exit_boot_services().
207 status = efi_get_memory_map(sys_table, &memory_map, &map_size,
208 &desc_size, &desc_ver, &mmap_key);
209 if (status != EFI_SUCCESS)
210 goto fail_free_new_fdt;
212 status = update_fdt(sys_table,
213 (void *)fdt_addr, fdt_size,
214 (void *)*new_fdt_addr, new_fdt_size,
215 cmdline_ptr, initrd_addr, initrd_size,
216 memory_map, map_size, desc_size, desc_ver);
218 /* Succeeding the first time is the expected case. */
219 if (status == EFI_SUCCESS)
222 if (status == EFI_BUFFER_TOO_SMALL) {
224 * We need to allocate more space for the new
225 * device tree, so free existing buffer that is
226 * too small. Also free memory map, as we will need
227 * to get new one that reflects the free/alloc we do
228 * on the device tree buffer.
230 efi_free(sys_table, new_fdt_size, *new_fdt_addr);
231 sys_table->boottime->free_pool(memory_map);
232 new_fdt_size += EFI_PAGE_SIZE;
234 pr_efi_err(sys_table, "Unable to constuct new device tree.\n");
239 /* Now we are ready to exit_boot_services.*/
240 status = sys_table->boottime->exit_boot_services(handle, mmap_key);
243 if (status == EFI_SUCCESS)
246 pr_efi_err(sys_table, "Exit boot services failed.\n");
249 sys_table->boottime->free_pool(memory_map);
252 efi_free(sys_table, new_fdt_size, *new_fdt_addr);
255 return EFI_LOAD_ERROR;
258 static void *get_fdt(efi_system_table_t *sys_table)
260 efi_guid_t fdt_guid = DEVICE_TREE_GUID;
261 efi_config_table_t *tables;
265 tables = (efi_config_table_t *) sys_table->tables;
268 for (i = 0; i < sys_table->nr_tables; i++)
269 if (efi_guidcmp(tables[i].guid, fdt_guid) == 0) {
270 fdt = (void *) tables[i].table;