include/bootflow.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * Copyright 2021 Google LLC
   4  * Written by Simon Glass <sjg@chromium.org>
   5  */
   6
   7 #ifndef __bootflow_h
   8 #define __bootflow_h
   9
  10 #include <bootdev.h>
  11 #include <dm/ofnode_decl.h>
  12 #include <linux/list.h>
  13
  14 struct bootstd_priv;
  15 struct expo;
  16
  17 enum {
  18         BOOTFLOW_MAX_USED_DEVS  = 16,
  19 };
  20
  21 /**
  22  * enum bootflow_state_t - states that a particular bootflow can be in
  23  *
  24  * Only bootflows in state BOOTFLOWST_READY can be used to boot.
  25  *
  26  * See bootflow_state[] for the names for each of these
  27  */
  28 enum bootflow_state_t {
  29         BOOTFLOWST_BASE,        /**< Nothing known yet */
  30         BOOTFLOWST_MEDIA,       /**< Media exists */
  31         BOOTFLOWST_PART,        /**< Partition exists */
  32         BOOTFLOWST_FS,          /**< Filesystem exists */
  33         BOOTFLOWST_FILE,        /**< Bootflow file exists */
  34         BOOTFLOWST_READY,       /**< Bootflow file loaded */
  35
  36         BOOTFLOWST_COUNT
  37 };
  38
  39 /**
  40  * enum bootflow_flags_t - flags for bootflows
  41  *
  42  * @BOOTFLOWF_USE_PRIOR_FDT: Indicates that an FDT was not found by the bootmeth
  43  *      and it is using the prior-stage FDT, which is the U-Boot control FDT.
  44  *      This is only possible with the EFI bootmeth (distro-efi) and only when
  45  *      CONFIG_OF_HAS_PRIOR_STAGE is enabled
  46  */
  47 enum bootflow_flags_t {
  48         BOOTFLOWF_USE_PRIOR_FDT = 1 << 0,
  49 };
  50
  51 /**
  52  * struct bootflow - information about a bootflow
  53  *
  54  * This is connected into two separate linked lists:
  55  *
  56  *   bm_sibling - links all bootflows in the same bootdev
  57  *   glob_sibling - links all bootflows in all bootdevs
  58  *
  59  * @bm_node: Points to siblings in the same bootdev
  60  * @glob_node: Points to siblings in the global list (all bootdev)
  61  * @dev: Bootdev device which produced this bootflow
  62  * @blk: Block device which contains this bootflow, NULL if this is a network
  63  *      device or sandbox 'host' device
  64  * @part: Partition number (0 for whole device)
  65  * @fs_type: Filesystem type (FS_TYPE...) if this is fixed by the media, else 0.
  66  *      For example, the sandbox host-filesystem bootdev sets this to
  67  *      FS_TYPE_SANDBOX
  68  * @method: Bootmethod device used to perform the boot and read files
  69  * @name: Name of bootflow (allocated)
  70  * @state: Current state (enum bootflow_state_t)
  71  * @subdir: Subdirectory to fetch files from (with trailing /), or NULL if none
  72  * @fname: Filename of bootflow file (allocated)
  73  * @logo: Logo to display for this bootflow (BMP format)
  74  * @logo_size: Size of the logo in bytes
  75  * @buf: Bootflow file contents (allocated)
  76  * @size: Size of bootflow file in bytes
  77  * @err: Error number received (0 if OK)
  78  * @os_name: Name of the OS / distro being booted, or NULL if not known
  79  *      (allocated)
  80  * @fdt_fname: Filename of FDT file
  81  * @fdt_size: Size of FDT file
  82  * @fdt_addr: Address of loaded fdt
  83  * @flags: Flags for the bootflow (see enum bootflow_flags_t)
  84  * @cmdline: OS command line, or NULL if not known (allocated)
  85  * @x86_setup: Pointer to x86 setup block inside @buf, NULL if not present
  86  * @bootmeth_priv: Private data for the bootmeth
  87  */
  88 struct bootflow {
  89         struct list_head bm_node;
  90         struct list_head glob_node;
  91         struct udevice *dev;
  92         struct udevice *blk;
  93         int part;
  94         int fs_type;
  95         struct udevice *method;
  96         char *name;
  97         enum bootflow_state_t state;
  98         char *subdir;
  99         char *fname;
 100         void *logo;
 101         uint logo_size;
 102         char *buf;
 103         int size;
 104         int err;
 105         char *os_name;
 106         char *fdt_fname;
 107         int fdt_size;
 108         ulong fdt_addr;
 109         int flags;
 110         char *cmdline;
 111         void *x86_setup;
 112         void *bootmeth_priv;
 113 };
 114
 115 /**
 116  * enum bootflow_iter_flags_t - flags for the bootflow iterator
 117  *
 118  * @BOOTFLOWIF_FIXED: Only used fixed/internal media
 119  * @BOOTFLOWIF_SHOW: Show each bootdev before scanning it; show each hunter
 120  * before using it
 121  * @BOOTFLOWIF_ALL: Return bootflows with errors as well
 122  * @BOOTFLOWIF_HUNT: Hunt for new bootdevs using the bootdrv hunters
 123  *
 124  * Internal flags:
 125  * @BOOTFLOWIF_SINGLE_DEV: (internal) Just scan one bootdev
 126  * @BOOTFLOWIF_SKIP_GLOBAL: (internal) Don't scan global bootmeths
 127  * @BOOTFLOWIF_SINGLE_UCLASS: (internal) Keep scanning through all devices in
 128  * this uclass (used with things like "mmc")
 129  * @BOOTFLOWIF_SINGLE_MEDIA: (internal) Scan one media device in the uclass (used
 130  * with things like "mmc1")
 131  */
 132 enum bootflow_iter_flags_t {
 133         BOOTFLOWIF_FIXED                = 1 << 0,
 134         BOOTFLOWIF_SHOW                 = 1 << 1,
 135         BOOTFLOWIF_ALL                  = 1 << 2,
 136         BOOTFLOWIF_HUNT                 = 1 << 3,
 137
 138         /*
 139          * flags used internally by standard boot - do not set these when
 140          * calling bootflow_scan_bootdev() etc.
 141          */
 142         BOOTFLOWIF_SINGLE_DEV           = 1 << 16,
 143         BOOTFLOWIF_SKIP_GLOBAL          = 1 << 17,
 144         BOOTFLOWIF_SINGLE_UCLASS        = 1 << 18,
 145         BOOTFLOWIF_SINGLE_MEDIA         = 1 << 19,
 146 };
 147
 148 /**
 149  * enum bootflow_meth_flags_t - flags controlling which bootmeths are used
 150  *
 151  * Used during iteration, e.g. by bootdev_find_by_label(), to determine which
 152  * bootmeths are used for the current bootdev. The flags reset when the bootdev
 153  * changes
 154  *
 155  * @BOOTFLOW_METHF_DHCP_ONLY: Only use dhcp (scripts and EFI)
 156  * @BOOTFLOW_METHF_PXE_ONLY: Only use pxe (PXE boot)
 157  * @BOOTFLOW_METHF_SINGLE_DEV: Scan only a single bootdev (used for labels like
 158  * "3"). This is used if a sequence number is provided instead of a label
 159  * @BOOTFLOW_METHF_SINGLE_UCLASS: Scan all bootdevs in this one uclass (used
 160  * with things like "mmc"). If this is not set, then the bootdev has an integer
 161  * value in the label (like "mmc2")
 162  */
 163 enum bootflow_meth_flags_t {
 164         BOOTFLOW_METHF_DHCP_ONLY        = 1 << 0,
 165         BOOTFLOW_METHF_PXE_ONLY         = 1 << 1,
 166         BOOTFLOW_METHF_SINGLE_DEV       = 1 << 2,
 167         BOOTFLOW_METHF_SINGLE_UCLASS    = 1 << 3,
 168 };
 169
 170 /**
 171  * struct bootflow_iter - state for iterating through bootflows
 172  *
 173  * This starts at with the first bootdev/partition/bootmeth and can be used to
 174  * iterate through all of them.
 175  *
 176  * Iteration starts with the bootdev. The first partition (0, i.e. whole device)
 177  * is scanned first. For partition 0, it iterates through all the available
 178  * bootmeths to see which one(s) can provide a bootflow. Then it moves to
 179  * parition 1 (if there is one) and the process continues. Once all partitions
 180  * are examined, it moves to the next bootdev.
 181  *
 182  * Initially @max_part is 0, meaning that only the whole device (@part=0) can be
 183  * used. During scanning, if a partition table is found, then @max_part is
 184  * updated to a larger value, no less than the number of available partitions.
 185  * This ensures that iteration works through all partitions on the bootdev.
 186  *
 187  * @flags: Flags to use (see enum bootflow_iter_flags_t). If
 188  *      BOOTFLOWIF_GLOBAL_FIRST is enabled then the global bootmeths are being
 189  *      scanned, otherwise we have moved onto the bootdevs
 190  * @dev: Current bootdev, NULL if none. This is only ever updated in
 191  * bootflow_iter_set_dev()
 192  * @part: Current partition number (0 for whole device)
 193  * @method: Current bootmeth
 194  * @max_part: Maximum hardware partition number in @dev, 0 if there is no
 195  *      partition table
 196  * @first_bootable: First bootable partition, or 0 if none
 197  * @err: Error obtained from checking the last iteration. This is used to skip
 198  *      forward (e.g. to skip the current partition because it is not valid)
 199  *      -ESHUTDOWN: try next bootdev
 200  * @num_devs: Number of bootdevs in @dev_used
 201  * @max_devs: Maximum number of entries in @dev_used
 202  * @dev_used: List of bootdevs used during iteration
 203  * @labels: List of labels to scan for bootdevs
 204  * @cur_label: Current label being processed
 205  * @num_methods: Number of bootmeth devices in @method_order
 206  * @cur_method: Current method number, an index into @method_order
 207  * @first_glob_method: First global method, if any, else -1
 208  * @cur_prio: Current priority being scanned
 209  * @method_order: List of bootmeth devices to use, in order. The normal methods
 210  *      appear first, then the global ones, if any
 211  * @doing_global: true if we are iterating through the global bootmeths (which
 212  *      happens before the normal ones)
 213  * @method_flags: flags controlling which methods should be used for this @dev
 214  * (enum bootflow_meth_flags_t)
 215  */
 216 struct bootflow_iter {
 217         int flags;
 218         struct udevice *dev;
 219         int part;
 220         struct udevice *method;
 221         int max_part;
 222         int first_bootable;
 223         int err;
 224         int num_devs;
 225         int max_devs;
 226         struct udevice *dev_used[BOOTFLOW_MAX_USED_DEVS];
 227         const char *const *labels;
 228         int cur_label;
 229         int num_methods;
 230         int cur_method;
 231         int first_glob_method;
 232         enum bootdev_prio_t cur_prio;
 233         struct udevice **method_order;
 234         bool doing_global;
 235         int method_flags;
 236 };
 237
 238 /**
 239  * bootflow_init() - Set up a bootflow struct
 240  *
 241  * The bootflow is zeroed and set to state BOOTFLOWST_BASE
 242  *
 243  * @bflow: Struct to set up
 244  * @bootdev: Bootdev to use
 245  * @meth: Bootmeth to use
 246  */
 247 void bootflow_init(struct bootflow *bflow, struct udevice *bootdev,
 248                    struct udevice *meth);
 249
 250 /**
 251  * bootflow_iter_init() - Reset a bootflow iterator
 252  *
 253  * This sets everything to the starting point, ready for use.
 254  *
 255  * @iter: Place to store private info (inited by this call)
 256  * @flags: Flags to use (see enum bootflow_iter_flags_t)
 257  */
 258 void bootflow_iter_init(struct bootflow_iter *iter, int flags);
 259
 260 /**
 261  * bootflow_iter_uninit() - Free memory used by an interator
 262  *
 263  * @iter:       Iterator to free
 264  */
 265 void bootflow_iter_uninit(struct bootflow_iter *iter);
 266
 267 /**
 268  * bootflow_iter_drop_bootmeth() - Remove a bootmeth from an iterator
 269  *
 270  * Update the iterator so that the bootmeth will not be used again while this
 271  * iterator is in use
 272  *
 273  * @iter: Iterator to update
 274  * @bmeth: Boot method to remove
 275  */
 276 int bootflow_iter_drop_bootmeth(struct bootflow_iter *iter,
 277                                 const struct udevice *bmeth);
 278
 279 /**
 280  * bootflow_scan_first() - find the first bootflow for a device or label
 281  *
 282  * If @flags includes BOOTFLOWIF_ALL then bootflows with errors are returned too
 283  *
 284  * @dev:        Boot device to scan, NULL to work through all of them until it
 285  *      finds one that can supply a bootflow
 286  * @label:      Label to control the scan, NULL to work through all devices
 287  *      until it finds one that can supply a bootflow
 288  * @iter:       Place to store private info (inited by this call)
 289  * @flags:      Flags for iterator (enum bootflow_iter_flags_t). Note that if
 290  *      @dev is NULL, then BOOTFLOWIF_SKIP_GLOBAL is set automatically by this
 291  *      function
 292  * @bflow:      Place to put the bootflow if found
 293  * Return: 0 if found,  -ENODEV if no device, other -ve on other error
 294  *      (iteration can continue)
 295  */
 296 int bootflow_scan_first(struct udevice *dev, const char *label,
 297                         struct bootflow_iter *iter, int flags,
 298                         struct bootflow *bflow);
 299
 300 /**
 301  * bootflow_scan_next() - find the next bootflow
 302  *
 303  * This works through the available bootdev devices until it finds one that
 304  * can supply a bootflow. It then returns that bootflow
 305  *
 306  * @iter:       Private info (as set up by bootflow_scan_first())
 307  * @bflow:      Place to put the bootflow if found
 308  * Return: 0 if found, -ENODEV if no device, -ESHUTDOWN if no more bootflows,
 309  *      other -ve on other error (iteration can continue)
 310  */
 311 int bootflow_scan_next(struct bootflow_iter *iter, struct bootflow *bflow);
 312
 313 /**
 314  * bootflow_first_glob() - Get the first bootflow from the global list
 315  *
 316  * Returns the first bootflow in the global list, no matter what bootflow it is
 317  * attached to
 318  *
 319  * @bflowp: Returns a pointer to the bootflow
 320  * Return: 0 if found, -ENOENT if there are no bootflows
 321  */
 322 int bootflow_first_glob(struct bootflow **bflowp);
 323
 324 /**
 325  * bootflow_next_glob() - Get the next bootflow from the global list
 326  *
 327  * Returns the next bootflow in the global list, no matter what bootflow it is
 328  * attached to
 329  *
 330  * @bflowp: On entry, the last bootflow returned , e.g. from
 331  *      bootflow_first_glob()
 332  * Return: 0 if found, -ENOENT if there are no more bootflows
 333  */
 334 int bootflow_next_glob(struct bootflow **bflowp);
 335
 336 /**
 337  * bootflow_free() - Free memory used by a bootflow
 338  *
 339  * This frees fields within @bflow, but not the @bflow pointer itself
 340  */
 341 void bootflow_free(struct bootflow *bflow);
 342
 343 /**
 344  * bootflow_boot() - boot a bootflow
 345  *
 346  * @bflow: Bootflow to boot
 347  * Return: -EPROTO if bootflow has not been loaded, -ENOSYS if the bootflow
 348  *      type is not supported, -EFAULT if the boot returned without an error
 349  *      when we are expecting it to boot, -ENOTSUPP if trying method resulted in
 350  *      finding out that is not actually supported for this boot and should not
 351  *      be tried again unless something changes
 352  */
 353 int bootflow_boot(struct bootflow *bflow);
 354
 355 /**
 356  * bootflow_read_all() - Read all bootflow files
 357  *
 358  * Some bootmeths delay reading of large files until booting is requested. This
 359  * causes those files to be read.
 360  *
 361  * @bflow: Bootflow to read
 362  * Return: result of trying to read
 363  */
 364 int bootflow_read_all(struct bootflow *bflow);
 365
 366 /**
 367  * bootflow_run_boot() - Try to boot a bootflow
 368  *
 369  * @iter: Current iteration (or NULL if none). Used to disable a bootmeth if the
 370  *      boot returns -ENOTSUPP
 371  * @bflow: Bootflow to boot
 372  * Return: result of trying to boot
 373  */
 374 int bootflow_run_boot(struct bootflow_iter *iter, struct bootflow *bflow);
 375
 376 /**
 377  * bootflow_state_get_name() - Get the name of a bootflow state
 378  *
 379  * @state: State to check
 380  * Return: name, or "?" if invalid
 381  */
 382 const char *bootflow_state_get_name(enum bootflow_state_t state);
 383
 384 /**
 385  * bootflow_remove() - Remove a bootflow and free its memory
 386  *
 387  * This updates the linked lists containing the bootflow then frees it.
 388  *
 389  * @bflow: Bootflow to remove
 390  */
 391 void bootflow_remove(struct bootflow *bflow);
 392
 393 /**
 394  * bootflow_iter_check_blk() - Check that a bootflow uses a block device
 395  *
 396  * This checks the bootdev in the bootflow to make sure it uses a block device
 397  *
 398  * Return: 0 if OK, -ENOTSUPP if some other device is used (e.g. ethernet)
 399  */
 400 int bootflow_iter_check_blk(const struct bootflow_iter *iter);
 401
 402 /**
 403  * bootflow_iter_check_sf() - Check that a bootflow uses SPI FLASH
 404  *
 405  * This checks the bootdev in the bootflow to make sure it uses SPI flash
 406  *
 407  * Return: 0 if OK, -ENOTSUPP if some other device is used (e.g. ethernet)
 408  */
 409 int bootflow_iter_check_sf(const struct bootflow_iter *iter);
 410
 411 /**
 412  * bootflow_iter_check_net() - Check that a bootflow uses a network device
 413  *
 414  * This checks the bootdev in the bootflow to make sure it uses a network
 415  * device
 416  *
 417  * Return: 0 if OK, -ENOTSUPP if some other device is used (e.g. MMC)
 418  */
 419 int bootflow_iter_check_net(const struct bootflow_iter *iter);
 420
 421 /**
 422  * bootflow_iter_check_system() - Check that a bootflow uses the bootstd device
 423  *
 424  * This checks the bootdev in the bootflow to make sure it uses the bootstd
 425  * device
 426  *
 427  * Return: 0 if OK, -ENOTSUPP if some other device is used (e.g. MMC)
 428  */
 429 int bootflow_iter_check_system(const struct bootflow_iter *iter);
 430
 431 /**
 432  * bootflow_menu_new() - Create a new bootflow menu
 433  *
 434  * @expp: Returns the expo created
 435  * Returns 0 on success, -ve on error
 436  */
 437 int bootflow_menu_new(struct expo **expp);
 438
 439 /**
 440  * bootflow_menu_apply_theme() - Apply a theme to a bootmenu
 441  *
 442  * @exp: Expo to update
 443  * @node: Node containing the theme information
 444  * Returns 0 on success, -ve on error
 445  */
 446 int bootflow_menu_apply_theme(struct expo *exp, ofnode node);
 447
 448 /**
 449  * bootflow_menu_run() - Create and run a menu of available bootflows
 450  *
 451  * @std: Bootstd information
 452  * @text_mode: Uses a text-based menu suitable for a serial port
 453  * @bflowp: Returns chosen bootflow (set to NULL if nothing is chosen)
 454  * @return 0 if an option was chosen, -EAGAIN if nothing was chosen, -ve on
 455  * error
 456  */
 457 int bootflow_menu_run(struct bootstd_priv *std, bool text_mode,
 458                       struct bootflow **bflowp);
 459
 460 #define BOOTFLOWCL_EMPTY        ((void *)1)
 461
 462 /**
 463  * cmdline_set_arg() - Update or read an argument in a cmdline string
 464  *
 465  * Handles updating a single arg in a cmdline string, returning it in a supplied
 466  * buffer; also reading an arg from a cmdline string
 467  *
 468  * When updating, consecutive spaces are squashed as are spaces at the start and
 469  * end.
 470  *
 471  * @buf: Working buffer to use (initial contents are ignored). Use NULL when
 472  * reading
 473  * @maxlen: Length of working buffer. Use 0 when reading
 474  * @cmdline: Command line to update, in the form:
 475  *
 476  *      fred mary= jane=123 john="has spaces"
 477  *
 478  * @set_arg: Argument to set or read (may or may not exist)
 479  * @new_val: Value for the new argument. May not include quotes (") but may
 480  * include embedded spaces, in which case it will be quoted when added to the
 481  * command line. Use NULL to delete the argument from @cmdline, BOOTFLOWCL_EMPTY
 482  * to set it to an empty value (no '=' sign after arg), "" to add an '=' sign
 483  * but with an empty value. Use NULL when reading.
 484  * @posp: Ignored when setting an argument; when getting an argument, returns
 485  * the start position of its value in @cmdline, after the first quote, if any
 486  *
 487  * Return:
 488  * For updating:
 489  *      length of new buffer (including \0 terminator) on success, -ENOENT if
 490  *      @new_val is NULL and @set_arg does not exist in @from, -EINVAL if a
 491  *      quoted arg-value in @from is not terminated with a quote, -EBADF if
 492  *      @new_val has spaces but does not start and end with quotes (or it has
 493  *      quotes in the middle of the string), -E2BIG if @maxlen is too small
 494  * For reading:
 495  *      length of arg value (excluding quotes), -ENOENT if not found
 496  */
 497 int cmdline_set_arg(char *buf, int maxlen, const char *cmdline,
 498                     const char *set_arg, const char *new_val, int *posp);
 499
 500 /**
 501  * bootflow_cmdline_set_arg() - Set a single argument for a bootflow
 502  *
 503  * Update the allocated cmdline and set the bootargs variable
 504  *
 505  * @bflow: Bootflow to update
 506  * @arg: Argument to update (e.g. "console")
 507  * @val: Value to set (e.g. "ttyS2") or NULL to delete the argument if present,
 508  * "" to set it to an empty value (e.g. "console=") and BOOTFLOWCL_EMPTY to add
 509  * it without any value ("initrd")
 510  * @set_env: true to set the "bootargs" environment variable too
 511  *
 512  * Return: 0 if OK, -ENOMEM if out of memory
 513  */
 514 int bootflow_cmdline_set_arg(struct bootflow *bflow, const char *arg,
 515                              const char *val, bool set_env);
 516
 517 /**
 518  * cmdline_get_arg() - Read an argument from a cmdline
 519  *
 520  * @cmdline: Command line to read, in the form:
 521  *
 522  *      fred mary= jane=123 john="has spaces"
 523  * @arg: Argument to read (may or may not exist)
 524  * @posp: Returns position of argument (after any leading quote) if present
 525  * Return: Length of argument value excluding quotes if found, -ENOENT if not
 526  * found
 527  */
 528 int cmdline_get_arg(const char *cmdline, const char *arg, int *posp);
 529
 530 /**
 531  * bootflow_cmdline_get_arg() - Read an argument from a cmdline
 532  *
 533  * @bootflow: Bootflow to read from
 534  * @arg: Argument to read (may or may not exist)
 535  * @valp: Returns a pointer to the argument (after any leading quote) if present
 536  * Return: Length of argument value excluding quotes if found, -ENOENT if not
 537  * found
 538  */
 539 int bootflow_cmdline_get_arg(struct bootflow *bflow, const char *arg,
 540                              const char **val);
 541
 542 /**
 543  * bootflow_cmdline_auto() - Automatically set a value for a known argument
 544  *
 545  * This handles a small number of known arguments, for Linux in particular. It
 546  * adds suitable kernel parameters automatically, e.g. to enable the console.
 547  *
 548  * @bflow: Bootflow to update
 549  * @arg: Name of argument to set (e.g. "earlycon" or "console")
 550  * Return: 0 if OK -ve on error
 551  */
 552 int bootflow_cmdline_auto(struct bootflow *bflow, const char *arg);
 553
 554 #endif