1 // SPDX-License-Identifier: GPL-2.0+
3 * Bootmethod for distro boot via EFI
5 * Copyright 2021 Google LLC
6 * Written by Simon Glass <sjg@chromium.org>
9 #define LOG_CATEGORY UCLASS_BOOTSTD
17 #include <efi_loader.h>
23 #include <pxe_utils.h>
24 #include <linux/sizes.h>
26 #define EFI_DIRNAME "efi/boot/"
29 * get_efi_leafname() - Get the leaf name for the EFI file we expect
31 * @str: Place to put leaf name for this architecture, e.g. "bootaa64.efi".
32 * Must have at least 16 bytes of space
33 * @max_len: Length of @str, must be >=16
35 static int get_efi_leafname(char *str, int max_len)
40 return log_msg_ret("spc", -ENOSPC);
41 if (IS_ENABLED(CONFIG_ARM64))
43 else if (IS_ENABLED(CONFIG_ARM))
45 else if (IS_ENABLED(CONFIG_X86_RUN_32BIT))
47 else if (IS_ENABLED(CONFIG_X86_RUN_64BIT))
49 else if (IS_ENABLED(CONFIG_ARCH_RV32I))
51 else if (IS_ENABLED(CONFIG_ARCH_RV64I))
53 else if (IS_ENABLED(CONFIG_SANDBOX))
64 static int get_efi_pxe_arch(void)
66 /* http://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xml */
67 if (IS_ENABLED(CONFIG_ARM64))
69 else if (IS_ENABLED(CONFIG_ARM))
71 else if (IS_ENABLED(CONFIG_X86_64))
73 else if (IS_ENABLED(CONFIG_X86))
75 else if (IS_ENABLED(CONFIG_ARCH_RV32I))
77 else if (IS_ENABLED(CONFIG_ARCH_RV64I))
79 else if (IS_ENABLED(CONFIG_SANDBOX))
80 return 0; /* not used */
85 static int get_efi_pxe_vci(char *str, int max_len)
89 ret = get_efi_pxe_arch();
93 snprintf(str, max_len, "PXEClient:Arch:%05x:UNDI:003000", ret);
99 * bootmeth_uses_network() - check if the media device is Ethernet
101 * @bflow: Bootflow to check
102 * Returns: true if the media device is Ethernet, else false
104 static bool bootmeth_uses_network(struct bootflow *bflow)
106 const struct udevice *media = dev_get_parent(bflow->dev);
108 return IS_ENABLED(CONFIG_CMD_DHCP) &&
109 device_get_uclass_id(media) == UCLASS_ETH;
112 static void set_efi_bootdev(struct blk_desc *desc, struct bootflow *bflow)
114 const struct udevice *media_dev;
115 int size = bflow->size;
116 const char *dev_name;
122 * This is a horrible hack to tell EFI about this boot device. Once we
123 * unify EFI with the rest of U-Boot we can clean this up. The same hack
124 * exists in multiple places, e.g. in the fs, tftp and load commands.
126 * Once we can clean up the EFI code to make proper use of driver model,
129 media_dev = dev_get_parent(bflow->dev);
130 snprintf(devnum_str, sizeof(devnum_str), "%x:%x",
131 desc ? desc->devnum : dev_seq(media_dev),
134 strlcpy(dirname, bflow->fname, sizeof(dirname));
135 last_slash = strrchr(dirname, '/');
139 log_debug("setting bootdev %s, %s, %s, %p, %x\n",
140 dev_get_uclass_name(media_dev), devnum_str, bflow->fname,
142 dev_name = device_get_uclass_id(media_dev) == UCLASS_MASS_STORAGE ?
143 "usb" : dev_get_uclass_name(media_dev);
144 efi_set_bootdev(dev_name, devnum_str, bflow->fname, bflow->buf, size);
147 static int efiload_read_file(struct bootflow *bflow, ulong addr)
149 struct blk_desc *desc = NULL;
154 desc = dev_get_uclass_plat(bflow->blk);
155 ret = bootmeth_setup_fs(bflow, desc);
157 return log_msg_ret("set", ret);
159 ret = fs_read(bflow->fname, addr, 0, bflow->size, &bytes_read);
161 return log_msg_ret("read", ret);
162 bflow->buf = map_sysmem(addr, bflow->size);
164 set_efi_bootdev(desc, bflow);
169 static int distro_efi_check(struct udevice *dev, struct bootflow_iter *iter)
171 /* This only works on block and network devices */
172 if (bootflow_iter_check_blk(iter) && bootflow_iter_check_net(iter))
173 return log_msg_ret("blk", -ENOTSUPP);
175 /* This works on block devices and network devices */
176 if (iter->method_flags & BOOTFLOW_METHF_PXE_ONLY)
177 return log_msg_ret("pxe", -ENOTSUPP);
183 * distro_efi_get_fdt_name() - Get the filename for reading the .dtb file
185 * @fname: Place to put filename
186 * @size: Max size of filename
187 * @seq: Sequence number, to cycle through options (0=first)
188 * Returns: 0 on success, -ENOENT if the "fdtfile" env var does not exist,
189 * -EINVAL if there are no more options, -EALREADY if the control FDT should be
192 static int distro_efi_get_fdt_name(char *fname, int size, int seq)
194 const char *fdt_fname;
197 /* select the prefix */
200 /* this is the default */
207 prefix = "/dtb/current";
210 return log_msg_ret("pref", -EINVAL);
213 fdt_fname = env_get("fdtfile");
215 snprintf(fname, size, "%s/%s", prefix, fdt_fname);
216 log_debug("Using device tree: %s\n", fname);
217 } else if (IS_ENABLED(CONFIG_OF_HAS_PRIOR_STAGE)) {
218 strcpy(fname, "<prior>");
219 return log_msg_ret("pref", -EALREADY);
220 /* Use this fallback only for 32-bit ARM */
221 } else if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_ARM64)) {
222 const char *soc = env_get("soc");
223 const char *board = env_get("board");
224 const char *boardver = env_get("boardver");
226 /* cf the code in label_boot() which seems very complex */
227 snprintf(fname, size, "%s/%s%s%s%s.dtb", prefix,
228 soc ? soc : "", soc ? "-" : "", board ? board : "",
229 boardver ? boardver : "");
230 log_debug("Using default device tree: %s\n", fname);
232 return log_msg_ret("env", -ENOENT);
239 * distro_efi_try_bootflow_files() - Check that files are present
241 * This reads any FDT file and checks whether the bootflow file is present, for
242 * later reading. We avoid reading the bootflow now, since it is likely large,
243 * it may take a long time and we want to avoid needing to allocate memory for
246 * @dev: bootmeth device to use
247 * @bflow: bootflow to update
249 static int distro_efi_try_bootflow_files(struct udevice *dev,
250 struct bootflow *bflow)
252 struct blk_desc *desc = NULL;
253 ulong fdt_addr, size;
257 /* We require a partition table */
261 strcpy(fname, EFI_DIRNAME);
262 ret = get_efi_leafname(fname + strlen(fname),
263 sizeof(fname) - strlen(fname));
265 return log_msg_ret("leaf", ret);
268 desc = dev_get_uclass_plat(bflow->blk);
269 ret = bootmeth_try_file(bflow, desc, NULL, fname);
271 return log_msg_ret("try", ret);
273 /* Since we can access the file, let's call it ready */
274 bflow->state = BOOTFLOWST_READY;
276 fdt_addr = env_get_hex("fdt_addr_r", 0);
278 /* try the various available names */
281 for (seq = 0; ret == -ENOENT; seq++) {
282 ret = distro_efi_get_fdt_name(fname, sizeof(fname), seq);
283 if (ret == -EALREADY)
284 bflow->flags = BOOTFLOWF_USE_PRIOR_FDT;
286 /* Limit FDT files to 4MB */
288 ret = bootmeth_common_read_file(dev, bflow, fname,
294 bflow->fdt_fname = strdup(fname);
295 if (!bflow->fdt_fname)
296 return log_msg_ret("fil", -ENOMEM);
300 bflow->fdt_size = size;
301 bflow->fdt_addr = fdt_addr;
304 * TODO: Apply extension overlay
306 * Here we need to load and apply the extension overlay. This is
307 * not implemented. See do_extension_apply(). The extension
308 * stuff needs an implementation in boot/extension.c so it is
309 * separate from the command code. Really the extension stuff
310 * should use the device tree and a uclass / driver interface
311 * rather than implementing its own list
314 log_debug("No device tree available\n");
315 bflow->flags |= BOOTFLOWF_USE_BUILTIN_FDT;
321 static int distro_efi_read_bootflow_net(struct bootflow *bflow)
323 char file_addr[17], fname[256];
324 char *tftp_argv[] = {"tftp", file_addr, fname, NULL};
325 struct cmd_tbl cmdtp = {}; /* dummy */
326 const char *addr_str, *fdt_addr_str, *bootfile_name;
328 ulong addr, fdt_addr;
331 ret = get_efi_pxe_vci(str, sizeof(str));
333 return log_msg_ret("vci", ret);
334 ret = get_efi_pxe_arch();
336 return log_msg_ret("arc", ret);
339 ret = env_set("bootp_vci", str);
341 return log_msg_ret("vcs", ret);
342 ret = env_set_hex("bootp_arch", arch);
344 return log_msg_ret("ars", ret);
346 /* figure out the load address */
347 addr_str = env_get("kernel_addr_r");
348 addr = addr_str ? hextoul(addr_str, NULL) : image_load_addr;
350 /* clear any previous bootfile */
351 env_set("bootfile", NULL);
353 /* read the kernel */
354 ret = dhcp_run(addr, NULL, true);
356 return log_msg_ret("dhc", ret);
358 size = env_get_hex("filesize", -1);
360 return log_msg_ret("sz", -EINVAL);
363 /* bootfile should be setup by dhcp*/
364 bootfile_name = env_get("bootfile");
366 return log_msg_ret("bootfile_name", ret);
367 bflow->fname = strdup(bootfile_name);
369 /* do the hideous EFI hack */
370 efi_set_bootdev("Net", "", bflow->fname, map_sysmem(addr, 0),
373 /* read the DT file also */
374 fdt_addr_str = env_get("fdt_addr_r");
376 return log_msg_ret("fdt", -EINVAL);
377 fdt_addr = hextoul(fdt_addr_str, NULL);
378 sprintf(file_addr, "%lx", fdt_addr);
380 /* We only allow the first prefix with PXE */
381 ret = distro_efi_get_fdt_name(fname, sizeof(fname), 0);
383 return log_msg_ret("nam", ret);
385 bflow->fdt_fname = strdup(fname);
386 if (!bflow->fdt_fname)
387 return log_msg_ret("fil", -ENOMEM);
389 if (!do_tftpb(&cmdtp, 0, 3, tftp_argv)) {
390 bflow->fdt_size = env_get_hex("filesize", 0);
391 bflow->fdt_addr = fdt_addr;
393 log_debug("No device tree available\n");
394 bflow->flags |= BOOTFLOWF_USE_BUILTIN_FDT;
397 bflow->state = BOOTFLOWST_READY;
402 static int distro_efi_read_bootflow(struct udevice *dev, struct bootflow *bflow)
407 * bootmeth_efi doesn't allocate any buffer neither for blk nor net device
408 * set flag to avoid freeing static buffer.
410 bflow->flags |= BOOTFLOWF_STATIC_BUF;
412 if (bootmeth_uses_network(bflow)) {
413 /* we only support reading from one device, so ignore 'dev' */
414 ret = distro_efi_read_bootflow_net(bflow);
416 return log_msg_ret("net", ret);
418 ret = distro_efi_try_bootflow_files(dev, bflow);
420 return log_msg_ret("blk", ret);
426 static int distro_efi_boot(struct udevice *dev, struct bootflow *bflow)
432 kernel = env_get_hex("kernel_addr_r", 0);
433 if (!bootmeth_uses_network(bflow)) {
434 ret = efiload_read_file(bflow, kernel);
436 return log_msg_ret("read", ret);
439 * use the provided device tree if not using the built-in fdt
441 if (bflow->flags & ~BOOTFLOWF_USE_BUILTIN_FDT)
442 fdt = bflow->fdt_addr;
446 * This doesn't actually work for network devices:
448 * do_bootefi_image() No UEFI binary known at 0x02080000
450 * But this is the same behaviour for distro boot, so it can be
453 fdt = env_get_hex("fdt_addr_r", 0);
457 * At some point we can add a real interface to bootefi so we can call
458 * this directly. For now, go through the CLI, like distro boot.
460 if (bflow->flags & BOOTFLOWF_USE_BUILTIN_FDT) {
461 log_debug("Booting with built-in fdt\n");
462 snprintf(cmd, sizeof(cmd), "bootefi %lx", kernel);
464 log_debug("Booting with external fdt\n");
465 snprintf(cmd, sizeof(cmd), "bootefi %lx %lx", kernel, fdt);
468 if (run_command(cmd, 0))
469 return log_msg_ret("run", -EINVAL);
474 static int distro_bootmeth_efi_bind(struct udevice *dev)
476 struct bootmeth_uc_plat *plat = dev_get_uclass_plat(dev);
478 plat->desc = IS_ENABLED(CONFIG_BOOTSTD_FULL) ?
479 "EFI boot from an .efi file" : "EFI";
484 static struct bootmeth_ops distro_efi_bootmeth_ops = {
485 .check = distro_efi_check,
486 .read_bootflow = distro_efi_read_bootflow,
487 .read_file = bootmeth_common_read_file,
488 .boot = distro_efi_boot,
491 static const struct udevice_id distro_efi_bootmeth_ids[] = {
492 { .compatible = "u-boot,distro-efi" },
496 U_BOOT_DRIVER(bootmeth_efi) = {
497 .name = "bootmeth_efi",
498 .id = UCLASS_BOOTMETH,
499 .of_match = distro_efi_bootmeth_ids,
500 .ops = &distro_efi_bootmeth_ops,
501 .bind = distro_bootmeth_efi_bind,