include/blk.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * (C) Copyright 2000-2004
   4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   5  */
   6
   7 #ifndef BLK_H
   8 #define BLK_H
   9
  10 #include <bouncebuf.h>
  11 #include <dm/uclass-id.h>
  12 #include <efi.h>
  13
  14 #ifdef CONFIG_SYS_64BIT_LBA
  15 typedef uint64_t lbaint_t;
  16 #define LBAFlength "ll"
  17 #else
  18 typedef ulong lbaint_t;
  19 #define LBAFlength "l"
  20 #endif
  21 #define LBAF "%" LBAFlength "x"
  22 #define LBAFU "%" LBAFlength "u"
  23
  24 #define DEFAULT_BLKSZ           512
  25
  26 struct udevice;
  27
  28 static inline bool blk_enabled(void)
  29 {
  30         return CONFIG_IS_ENABLED(BLK) || IS_ENABLED(CONFIG_SPL_LEGACY_BLOCK);
  31 }
  32
  33 #define BLK_VEN_SIZE            40
  34 #define BLK_PRD_SIZE            20
  35 #define BLK_REV_SIZE            8
  36
  37 #define PART_FORMAT_PCAT        0x1
  38 #define PART_FORMAT_GPT         0x2
  39
  40 /*
  41  * Identifies the partition table type (ie. MBR vs GPT GUID) signature
  42  */
  43 enum sig_type {
  44         SIG_TYPE_NONE,
  45         SIG_TYPE_MBR,
  46         SIG_TYPE_GUID,
  47
  48         SIG_TYPE_COUNT                  /* Number of signature types */
  49 };
  50
  51 /*
  52  * With driver model (CONFIG_BLK) this is uclass platform data, accessible
  53  * with dev_get_uclass_plat(dev)
  54  */
  55 struct blk_desc {
  56         /*
  57          * TODO: With driver model we should be able to use the parent
  58          * device's uclass instead.
  59          */
  60         enum uclass_id  uclass_id;      /* type of the interface */
  61         int             devnum;         /* device number */
  62         unsigned char   part_type;      /* partition type */
  63         unsigned char   target;         /* target SCSI ID */
  64         unsigned char   lun;            /* target LUN */
  65         unsigned char   hwpart;         /* HW partition, e.g. for eMMC */
  66         unsigned char   type;           /* device type */
  67         unsigned char   removable;      /* removable device */
  68         /* device can use 48bit addr (ATA/ATAPI v7) */
  69         bool    lba48;
  70         unsigned char   atapi;          /* Use ATAPI protocol */
  71         unsigned char   bb;             /* Use bounce buffer */
  72         lbaint_t        lba;            /* number of blocks */
  73         unsigned long   blksz;          /* block size */
  74         int             log2blksz;      /* for convenience: log2(blksz) */
  75         char            vendor[BLK_VEN_SIZE + 1]; /* device vendor string */
  76         char            product[BLK_PRD_SIZE + 1]; /* device product number */
  77         char            revision[BLK_REV_SIZE + 1]; /* firmware revision */
  78         enum sig_type   sig_type;       /* Partition table signature type */
  79         union {
  80                 uint32_t mbr_sig;       /* MBR integer signature */
  81                 efi_guid_t guid_sig;    /* GPT GUID Signature */
  82         };
  83 #if CONFIG_IS_ENABLED(BLK)
  84         /*
  85          * For now we have a few functions which take struct blk_desc as a
  86          * parameter. This field allows them to look up the associated
  87          * device. Once these functions are removed we can drop this field.
  88          */
  89         struct udevice *bdev;
  90 #else
  91         unsigned long   (*block_read)(struct blk_desc *block_dev,
  92                                       lbaint_t start,
  93                                       lbaint_t blkcnt,
  94                                       void *buffer);
  95         unsigned long   (*block_write)(struct blk_desc *block_dev,
  96                                        lbaint_t start,
  97                                        lbaint_t blkcnt,
  98                                        const void *buffer);
  99         unsigned long   (*block_erase)(struct blk_desc *block_dev,
 100                                        lbaint_t start,
 101                                        lbaint_t blkcnt);
 102         void            *priv;          /* driver private struct pointer */
 103 #endif
 104 };
 105
 106 #define BLOCK_CNT(size, blk_desc) (PAD_COUNT(size, blk_desc->blksz))
 107 #define PAD_TO_BLOCKSIZE(size, blk_desc) \
 108         (PAD_SIZE(size, blk_desc->blksz))
 109
 110 #if CONFIG_IS_ENABLED(BLOCK_CACHE)
 111 /**
 112  * blkcache_read() - attempt to read a set of blocks from cache
 113  *
 114  * @param iftype - uclass_id_x for type of device
 115  * @param dev - device index of particular type
 116  * @param start - starting block number
 117  * @param blkcnt - number of blocks to read
 118  * @param blksz - size in bytes of each block
 119  * @param buffer - buffer to contain cached data
 120  *
 121  * Return: - 1 if block returned from cache, 0 otherwise.
 122  */
 123 int blkcache_read(int iftype, int dev,
 124                   lbaint_t start, lbaint_t blkcnt,
 125                   unsigned long blksz, void *buffer);
 126
 127 /**
 128  * blkcache_fill() - make data read from a block device available
 129  * to the block cache
 130  *
 131  * @param iftype - uclass_id_x for type of device
 132  * @param dev - device index of particular type
 133  * @param start - starting block number
 134  * @param blkcnt - number of blocks available
 135  * @param blksz - size in bytes of each block
 136  * @param buffer - buffer containing data to cache
 137  *
 138  */
 139 void blkcache_fill(int iftype, int dev,
 140                    lbaint_t start, lbaint_t blkcnt,
 141                    unsigned long blksz, void const *buffer);
 142
 143 /**
 144  * blkcache_invalidate() - discard the cache for a set of blocks
 145  * because of a write or device (re)initialization.
 146  *
 147  * @iftype - UCLASS_ID_ for type of device, or -1 for any
 148  * @dev - device index of particular type, if @iftype is not -1
 149  */
 150 void blkcache_invalidate(int iftype, int dev);
 151
 152 /**
 153  * blkcache_configure() - configure block cache
 154  *
 155  * @param blocks - maximum blocks per entry
 156  * @param entries - maximum entries in cache
 157  */
 158 void blkcache_configure(unsigned blocks, unsigned entries);
 159
 160 /*
 161  * statistics of the block cache
 162  */
 163 struct block_cache_stats {
 164         unsigned hits;
 165         unsigned misses;
 166         unsigned entries; /* current entry count */
 167         unsigned max_blocks_per_entry;
 168         unsigned max_entries;
 169 };
 170
 171 /**
 172  * get_blkcache_stats() - return statistics and reset
 173  *
 174  * @param stats - statistics are copied here
 175  */
 176 void blkcache_stats(struct block_cache_stats *stats);
 177
 178 /** blkcache_free() - free all memory allocated to the block cache */
 179 void blkcache_free(void);
 180
 181 #else
 182
 183 static inline int blkcache_read(int iftype, int dev,
 184                                 lbaint_t start, lbaint_t blkcnt,
 185                                 unsigned long blksz, void *buffer)
 186 {
 187         return 0;
 188 }
 189
 190 static inline void blkcache_fill(int iftype, int dev,
 191                                  lbaint_t start, lbaint_t blkcnt,
 192                                  unsigned long blksz, void const *buffer) {}
 193
 194 static inline void blkcache_invalidate(int iftype, int dev) {}
 195
 196 static inline void blkcache_free(void) {}
 197
 198 #endif
 199
 200 struct udevice;
 201
 202 /* Operations on block devices */
 203 struct blk_ops {
 204         /**
 205          * read() - read from a block device
 206          *
 207          * @dev:        Device to read from
 208          * @start:      Start block number to read (0=first)
 209          * @blkcnt:     Number of blocks to read
 210          * @buffer:     Destination buffer for data read
 211          * @return number of blocks read, or -ve error number (see the
 212          * IS_ERR_VALUE() macro
 213          */
 214         unsigned long (*read)(struct udevice *dev, lbaint_t start,
 215                               lbaint_t blkcnt, void *buffer);
 216
 217         /**
 218          * write() - write to a block device
 219          *
 220          * @dev:        Device to write to
 221          * @start:      Start block number to write (0=first)
 222          * @blkcnt:     Number of blocks to write
 223          * @buffer:     Source buffer for data to write
 224          * @return number of blocks written, or -ve error number (see the
 225          * IS_ERR_VALUE() macro
 226          */
 227         unsigned long (*write)(struct udevice *dev, lbaint_t start,
 228                                lbaint_t blkcnt, const void *buffer);
 229
 230         /**
 231          * erase() - erase a section of a block device
 232          *
 233          * @dev:        Device to (partially) erase
 234          * @start:      Start block number to erase (0=first)
 235          * @blkcnt:     Number of blocks to erase
 236          * @return number of blocks erased, or -ve error number (see the
 237          * IS_ERR_VALUE() macro
 238          */
 239         unsigned long (*erase)(struct udevice *dev, lbaint_t start,
 240                                lbaint_t blkcnt);
 241
 242         /**
 243          * select_hwpart() - select a particular hardware partition
 244          *
 245          * Some devices (e.g. MMC) can support partitioning at the hardware
 246          * level. This is quite separate from the normal idea of
 247          * software-based partitions. MMC hardware partitions must be
 248          * explicitly selected. Once selected only the region of the device
 249          * covered by that partition is accessible.
 250          *
 251          * The MMC standard provides for two boot partitions (numbered 1 and 2),
 252          * rpmb (3), and up to 4 addition general-purpose partitions (4-7).
 253          *
 254          * @dev:        Block device to update
 255          * @hwpart:     Hardware partition number to select. 0 means the raw
 256          *              device, 1 is the first partition, 2 is the second, etc.
 257          * @return 0 if OK, -ve on error
 258          */
 259         int (*select_hwpart)(struct udevice *dev, int hwpart);
 260
 261 #if IS_ENABLED(CONFIG_BOUNCE_BUFFER)
 262         /**
 263          * buffer_aligned() - test memory alignment of block operation buffer
 264          *
 265          * Some devices have limited DMA capabilities and require that the
 266          * buffers passed to them fit specific properties. This optional
 267          * callback can be used to indicate whether a buffer alignment is
 268          * suitable for the device DMA or not, and trigger use of generic
 269          * bounce buffer implementation to help use of unsuitable buffers
 270          * at the expense of performance degradation.
 271          *
 272          * @dev:        Block device associated with the request
 273          * @state:      Bounce buffer state
 274          * @return 1 if OK, 0 if unaligned
 275          */
 276         int (*buffer_aligned)(struct udevice *dev, struct bounce_buffer *state);
 277 #endif  /* CONFIG_BOUNCE_BUFFER */
 278 };
 279
 280 #if CONFIG_IS_ENABLED(BLK)
 281
 282 /*
 283  * These functions should take struct udevice instead of struct blk_desc,
 284  * but this is convenient for migration to driver model. Add a 'd' prefix
 285  * to the function operations, so that blk_read(), etc. can be reserved for
 286  * functions with the correct arguments.
 287  */
 288 unsigned long blk_dread(struct blk_desc *block_dev, lbaint_t start,
 289                         lbaint_t blkcnt, void *buffer);
 290 unsigned long blk_dwrite(struct blk_desc *block_dev, lbaint_t start,
 291                          lbaint_t blkcnt, const void *buffer);
 292 unsigned long blk_derase(struct blk_desc *block_dev, lbaint_t start,
 293                          lbaint_t blkcnt);
 294
 295 #endif /* BLK */
 296
 297 /**
 298  * blk_read() - Read from a block device
 299  *
 300  * @dev: Device to read from
 301  * @start: Start block for the read
 302  * @blkcnt: Number of blocks to read
 303  * @buf: Place to put the data
 304  * @return number of blocks read (which may be less than @blkcnt),
 305  * or -ve on error. This never returns 0 unless @blkcnt is 0
 306  */
 307 long blk_read(struct udevice *dev, lbaint_t start, lbaint_t blkcnt,
 308               void *buffer);
 309
 310 /**
 311  * blk_write() - Write to a block device
 312  *
 313  * @dev: Device to write to
 314  * @start: Start block for the write
 315  * @blkcnt: Number of blocks to write
 316  * @buf: Data to write
 317  * @return number of blocks written (which may be less than @blkcnt),
 318  * or -ve on error. This never returns 0 unless @blkcnt is 0
 319  */
 320 long blk_write(struct udevice *dev, lbaint_t start, lbaint_t blkcnt,
 321                const void *buffer);
 322
 323 /**
 324  * blk_erase() - Erase part of a block device
 325  *
 326  * @dev: Device to erase
 327  * @start: Start block for the erase
 328  * @blkcnt: Number of blocks to erase
 329  * @return number of blocks erased (which may be less than @blkcnt),
 330  * or -ve on error. This never returns 0 unless @blkcnt is 0
 331  */
 332 long blk_erase(struct udevice *dev, lbaint_t start, lbaint_t blkcnt);
 333
 334 /**
 335  * blk_find_device() - Find a block device
 336  *
 337  * This function does not activate the device. The device will be returned
 338  * whether or not it is activated.
 339  *
 340  * @uclass_id:  Interface type (enum uclass_id_t)
 341  * @devnum:     Device number (specific to each interface type)
 342  * @devp:       the device, if found
 343  * Return: 0 if found, -ENODEV if no device found, or other -ve error value
 344  */
 345 int blk_find_device(int uclass_id, int devnum, struct udevice **devp);
 346
 347 /**
 348  * blk_get_device() - Find and probe a block device ready for use
 349  *
 350  * @uclass_id:  Interface type (enum uclass_id_t)
 351  * @devnum:     Device number (specific to each interface type)
 352  * @devp:       the device, if found
 353  * Return: 0 if found, -ENODEV if no device found, or other -ve error value
 354  */
 355 int blk_get_device(int uclass_id, int devnum, struct udevice **devp);
 356
 357 /**
 358  * blk_first_device() - Find the first device for a given interface
 359  *
 360  * The device is probed ready for use
 361  *
 362  * @devnum:     Device number (specific to each interface type)
 363  * @devp:       the device, if found
 364  * Return: 0 if found, -ENODEV if no device, or other -ve error value
 365  */
 366 int blk_first_device(int uclass_id, struct udevice **devp);
 367
 368 /**
 369  * blk_next_device() - Find the next device for a given interface
 370  *
 371  * This can be called repeatedly after blk_first_device() to iterate through
 372  * all devices of the given interface type.
 373  *
 374  * The device is probed ready for use
 375  *
 376  * @devp:       On entry, the previous device returned. On exit, the next
 377  *              device, if found
 378  * Return: 0 if found, -ENODEV if no device, or other -ve error value
 379  */
 380 int blk_next_device(struct udevice **devp);
 381
 382 /**
 383  * blk_create_devicef() - Create a new named block device
 384  *
 385  * @parent:     Parent of the new device
 386  * @drv_name:   Driver name to use for the block device
 387  * @name:       Name for the device (parent name is prepended)
 388  * @uclass_id:  Interface type (enum uclass_id_t)
 389  * @devnum:     Device number, specific to the interface type, or -1 to
 390  *              allocate the next available number
 391  * @blksz:      Block size of the device in bytes (typically 512)
 392  * @lba:        Total number of blocks of the device
 393  * @devp:       the new device (which has not been probed)
 394  */
 395 int blk_create_devicef(struct udevice *parent, const char *drv_name,
 396                        const char *name, int uclass_id, int devnum, int blksz,
 397                        lbaint_t lba, struct udevice **devp);
 398
 399 /**
 400  * blk_probe_or_unbind() - Try to probe
 401  *
 402  * Try to probe the device, primarily for enumerating partitions.
 403  * If it fails, the device itself is unbound since it means that it won't
 404  * work any more.
 405  *
 406  * @dev:        The device to probe
 407  * Return:      0 if OK, -ve on error
 408  */
 409 int blk_probe_or_unbind(struct udevice *dev);
 410
 411 /**
 412  * blk_unbind_all() - Unbind all device of the given interface type
 413  *
 414  * The devices are removed and then unbound.
 415  *
 416  * @uclass_id:  Interface type to unbind
 417  * Return: 0 if OK, -ve on error
 418  */
 419 int blk_unbind_all(int uclass_id);
 420
 421 /**
 422  * blk_find_max_devnum() - find the maximum device number for an interface type
 423  *
 424  * Finds the last allocated device number for an interface type @uclass_id. The
 425  * next number is safe to use for a newly allocated device.
 426  *
 427  * @uclass_id:  Interface type to scan
 428  * Return: maximum device number found, or -ENODEV if none, or other -ve on
 429  * error
 430  */
 431 int blk_find_max_devnum(enum uclass_id uclass_id);
 432
 433 /**
 434  * blk_next_free_devnum() - get the next device number for an interface type
 435  *
 436  * Finds the next number that is safe to use for a newly allocated device for
 437  * an interface type @uclass_id.
 438  *
 439  * @uclass_id:  Interface type to scan
 440  * Return: next device number safe to use, or -ve on error
 441  */
 442 int blk_next_free_devnum(enum uclass_id uclass_id);
 443
 444 /**
 445  * blk_select_hwpart() - select a hardware partition
 446  *
 447  * Select a hardware partition if the device supports it (typically MMC does)
 448  *
 449  * @dev:        Device to update
 450  * @hwpart:     Partition number to select
 451  * Return: 0 if OK, -ve on error
 452  */
 453 int blk_select_hwpart(struct udevice *dev, int hwpart);
 454
 455 /**
 456  * blk_find_from_parent() - find a block device by looking up its parent
 457  *
 458  * All block devices have a parent 'media' device which provides the block
 459  * driver for the block device, ensuring that access to the underlying medium
 460  * is available.
 461  *
 462  * The block device is not activated by this function. See
 463  * blk_get_from_parent() for that.
 464  *
 465  * @parent: Media device
 466  * @devp: Returns the associated block device, if any
 467  * Returns: 0 if OK, -ENODEV if @parent is not a media device and has no
 468  * UCLASS_BLK child
 469  */
 470 int blk_find_from_parent(struct udevice *parent, struct udevice **devp);
 471
 472 /**
 473  * blk_get_from_parent() - obtain a block device by looking up its parent
 474  *
 475  * All block devices have a parent 'media' device which provides the block
 476  * driver for the block device, ensuring that access to the underlying medium
 477  * is available.
 478  *
 479  * The block device is probed and ready for use.
 480  *
 481  * @parent: Media device
 482  * @devp: Returns the associated block device, if any
 483  * Returns: 0 if OK, -ENODEV if @parent is not a media device and has no
 484  * UCLASS_BLK child
 485  */
 486 int blk_get_from_parent(struct udevice *parent, struct udevice **devp);
 487
 488 /**
 489  * blk_get_devtype() - Get the device type of a block device
 490  *
 491  * @dev:        Block device to check
 492  * Return: device tree, i.e. the uclass name of its parent, e.g. "mmc"
 493  */
 494 const char *blk_get_devtype(struct udevice *dev);
 495
 496 /**
 497  * blk_get_by_device() - Get the block device descriptor for the given device
 498  * @dev:        Instance of a storage device (the parent of the block device)
 499  *
 500  * Return: With block device descriptor on success , NULL if there is no such
 501  *         block device.
 502  */
 503 struct blk_desc *blk_get_by_device(struct udevice *dev);
 504
 505 /**
 506  * blk_get_desc() - Get the block device descriptor for the given device number
 507  *
 508  * @uclass_id:  Interface type
 509  * @devnum:     Device number (0 = first)
 510  * @descp:      Returns block device descriptor on success
 511  * Return: 0 on success, -ENODEV if there is no such device and no device
 512  * with a higher device number, -ENOENT if there is no such device but there
 513  * is one with a higher number, or other -ve on other error.
 514  */
 515 int blk_get_desc(enum uclass_id uclass_id, int devnum, struct blk_desc **descp);
 516
 517 #if !CONFIG_IS_ENABLED(BLK)
 518
 519 #include <errno.h>
 520
 521 /*
 522  * These functions should take struct udevice instead of struct blk_desc,
 523  * but this is convenient for migration to driver model. Add a 'd' prefix
 524  * to the function operations, so that blk_read(), etc. can be reserved for
 525  * functions with the correct arguments.
 526  */
 527 static inline ulong blk_dread(struct blk_desc *block_dev, lbaint_t start,
 528                               lbaint_t blkcnt, void *buffer)
 529 {
 530         ulong blks_read;
 531         if (blkcache_read(block_dev->uclass_id, block_dev->devnum,
 532                           start, blkcnt, block_dev->blksz, buffer))
 533                 return blkcnt;
 534
 535         /*
 536          * We could check if block_read is NULL and return -ENOSYS. But this
 537          * bloats the code slightly (cause some board to fail to build), and
 538          * it would be an error to try an operation that does not exist.
 539          */
 540         blks_read = block_dev->block_read(block_dev, start, blkcnt, buffer);
 541         if (blks_read == blkcnt)
 542                 blkcache_fill(block_dev->uclass_id, block_dev->devnum,
 543                               start, blkcnt, block_dev->blksz, buffer);
 544
 545         return blks_read;
 546 }
 547
 548 static inline ulong blk_dwrite(struct blk_desc *block_dev, lbaint_t start,
 549                                lbaint_t blkcnt, const void *buffer)
 550 {
 551         blkcache_invalidate(block_dev->uclass_id, block_dev->devnum);
 552         return block_dev->block_write(block_dev, start, blkcnt, buffer);
 553 }
 554
 555 static inline ulong blk_derase(struct blk_desc *block_dev, lbaint_t start,
 556                                lbaint_t blkcnt)
 557 {
 558         blkcache_invalidate(block_dev->uclass_id, block_dev->devnum);
 559         return block_dev->block_erase(block_dev, start, blkcnt);
 560 }
 561
 562 /**
 563  * struct blk_driver - Driver for block interface types
 564  *
 565  * This provides access to the block devices for each interface type. One
 566  * driver should be provided using U_BOOT_LEGACY_BLK() for each interface
 567  * type that is to be supported.
 568  *
 569  * @uclass_idname:      Interface type name
 570  * @uclass_id:          Interface type
 571  * @max_devs:           Maximum number of devices supported
 572  * @desc:               Pointer to list of devices for this interface type,
 573  *                      or NULL to use @get_dev() instead
 574  */
 575 struct blk_driver {
 576         const char *uclass_idname;
 577         enum uclass_id uclass_id;
 578         int max_devs;
 579         struct blk_desc *desc;
 580         /**
 581          * get_dev() - get a pointer to a block device given its number
 582          *
 583          * Each interface allocates its own devices and typically
 584          * struct blk_desc is contained with the interface's data structure.
 585          * There is no global numbering for block devices. This method allows
 586          * the device for an interface type to be obtained when @desc is NULL.
 587          *
 588          * @devnum:     Device number (0 for first device on that interface,
 589          *              1 for second, etc.
 590          * @descp:      Returns pointer to the block device on success
 591          * @return 0 if OK, -ve on error
 592          */
 593         int (*get_dev)(int devnum, struct blk_desc **descp);
 594
 595         /**
 596          * select_hwpart() - Select a hardware partition
 597          *
 598          * Some devices (e.g. MMC) can support partitioning at the hardware
 599          * level. This is quite separate from the normal idea of
 600          * software-based partitions. MMC hardware partitions must be
 601          * explicitly selected. Once selected only the region of the device
 602          * covered by that partition is accessible.
 603          *
 604          * The MMC standard provides for two boot partitions (numbered 1 and 2),
 605          * rpmb (3), and up to 4 addition general-purpose partitions (4-7).
 606          * Partition 0 is the main user-data partition.
 607          *
 608          * @desc:       Block device descriptor
 609          * @hwpart:     Hardware partition number to select. 0 means the main
 610          *              user-data partition, 1 is the first partition, 2 is
 611          *              the second, etc.
 612          * @return 0 if OK, other value for an error
 613          */
 614         int (*select_hwpart)(struct blk_desc *desc, int hwpart);
 615 };
 616
 617 /*
 618  * Declare a new U-Boot legacy block driver. New drivers should use driver
 619  * model (UCLASS_BLK).
 620  */
 621 #define U_BOOT_LEGACY_BLK(__name)                                       \
 622         ll_entry_declare(struct blk_driver, __name, blk_driver)
 623
 624 struct blk_driver *blk_driver_lookup_type(int uclass_id);
 625
 626 #endif /* !CONFIG_BLK */
 627
 628 /**
 629  * blk_get_devnum_by_uclass_idname() - Get a block device by type and number
 630  *
 631  * This looks through the available block devices of the given type, returning
 632  * the one with the given @devnum.
 633  *
 634  * @uclass_id:  Block device type
 635  * @devnum:     Device number
 636  * Return: point to block device descriptor, or NULL if not found
 637  */
 638 struct blk_desc *blk_get_devnum_by_uclass_id(enum uclass_id uclass_id, int devnum);
 639
 640 /**
 641  * blk_get_devnum_by_uclass_idname() - Get block device by type name and number
 642  *
 643  * This looks up the block device type based on @uclass_idname, then calls
 644  * blk_get_devnum_by_uclass_id().
 645  *
 646  * @uclass_idname:      Block device type name
 647  * @devnum:             Device number
 648  * Return: point to block device descriptor, or NULL if not found
 649  */
 650 struct blk_desc *blk_get_devnum_by_uclass_idname(const char *uclass_idname,
 651                                                  int devnum);
 652
 653 /**
 654  * blk_dselect_hwpart() - select a hardware partition
 655  *
 656  * This selects a hardware partition (such as is supported by MMC). The block
 657  * device size may change as this effectively points the block device to a
 658  * partition at the hardware level. See the select_hwpart() method above.
 659  *
 660  * @desc:       Block device descriptor for the device to select
 661  * @hwpart:     Partition number to select
 662  * Return: 0 if OK, -ve on error
 663  */
 664 int blk_dselect_hwpart(struct blk_desc *desc, int hwpart);
 665
 666 /**
 667  * blk_list_part() - list the partitions for block devices of a given type
 668  *
 669  * This looks up the partition type for each block device of type @uclass_id,
 670  * then displays a list of partitions.
 671  *
 672  * @uclass_id:  Block device type
 673  * Return: 0 if OK, -ENODEV if there is none of that type
 674  */
 675 int blk_list_part(enum uclass_id uclass_id);
 676
 677 /**
 678  * blk_list_devices() - list the block devices of a given type
 679  *
 680  * This lists each block device of the type @uclass_id, showing the capacity
 681  * as well as type-specific information.
 682  *
 683  * @uclass_id:  Block device type
 684  */
 685 void blk_list_devices(enum uclass_id uclass_id);
 686
 687 /**
 688  * blk_show_device() - show information about a given block device
 689  *
 690  * This shows the block device capacity as well as type-specific information.
 691  *
 692  * @uclass_id:  Block device type
 693  * @devnum:     Device number
 694  * Return: 0 if OK, -ENODEV for invalid device number
 695  */
 696 int blk_show_device(enum uclass_id uclass_id, int devnum);
 697
 698 /**
 699  * blk_print_device_num() - show information about a given block device
 700  *
 701  * This is similar to blk_show_device() but returns an error if the block
 702  * device type is unknown.
 703  *
 704  * @uclass_id:  Block device type
 705  * @devnum:     Device number
 706  * Return: 0 if OK, -ENODEV for invalid device number, -ENOENT if the block
 707  * device is not connected
 708  */
 709 int blk_print_device_num(enum uclass_id uclass_id, int devnum);
 710
 711 /**
 712  * blk_print_part_devnum() - print the partition information for a device
 713  *
 714  * @uclass_id:  Block device type
 715  * @devnum:     Device number
 716  * Return: 0 if OK, -ENOENT if the block device is not connected, -ENOSYS if
 717  * the interface type is not supported, other -ve on other error
 718  */
 719 int blk_print_part_devnum(enum uclass_id uclass_id, int devnum);
 720
 721 /**
 722  * blk_select_hwpart_devnum() - select a hardware partition
 723  *
 724  * This is similar to blk_dselect_hwpart() but it looks up the interface and
 725  * device number.
 726  *
 727  * @uclass_id:  Block device type
 728  * @devnum:     Device number
 729  * @hwpart:     Partition number to select
 730  * Return: 0 if OK, -ve on error
 731  */
 732 int blk_select_hwpart_devnum(enum uclass_id uclass_id, int devnum, int hwpart);
 733
 734 /**
 735  * blk_get_uclass_name() - Get the name of an interface type
 736  *
 737  * @uclass_id: Interface type to check
 738  * Return: name of interface, or NULL if none
 739  */
 740 const char *blk_get_uclass_name(enum uclass_id uclass_id);
 741
 742 /**
 743  * blk_common_cmd() - handle common commands with block devices
 744  *
 745  * @args: Number of arguments to the command (argv[0] is the command itself)
 746  * @argv: Command arguments
 747  * @uclass_id: Interface type
 748  * @cur_devnump: Current device number for this interface type
 749  * Return: 0 if OK, CMD_RET_ERROR on error
 750  */
 751 int blk_common_cmd(int argc, char *const argv[], enum uclass_id uclass_id,
 752                    int *cur_devnump);
 753
 754 enum blk_flag_t {
 755         BLKF_FIXED      = 1 << 0,
 756         BLKF_REMOVABLE  = 1 << 1,
 757         BLKF_BOTH       = BLKF_FIXED | BLKF_REMOVABLE,
 758 };
 759
 760 /**
 761  * blk_first_device_err() - Get the first block device
 762  *
 763  * The device returned is probed if necessary, and ready for use
 764  *
 765  * @flags: Indicates type of device to return
 766  * @devp: Returns pointer to the first device in that uclass, or NULL if none
 767  * Return: 0 if found, -ENODEV if not found, other -ve on error
 768  */
 769 int blk_first_device_err(enum blk_flag_t flags, struct udevice **devp);
 770
 771 /**
 772  * blk_next_device_err() - Get the next block device
 773  *
 774  * The device returned is probed if necessary, and ready for use
 775  *
 776  * @flags: Indicates type of device to return
 777  * @devp: On entry, pointer to device to lookup. On exit, returns pointer
 778  * to the next device in the uclass if no error occurred, or -ENODEV if
 779  * there is no next device.
 780  * Return: 0 if found, -ENODEV if not found, other -ve on error
 781  */
 782 int blk_next_device_err(enum blk_flag_t flags, struct udevice **devp);
 783
 784 /**
 785  * blk_find_first() - Return the first matching block device
 786  * @flags: Indicates type of device to return
 787  * @devp:       Returns pointer to device, or NULL on error
 788  *
 789  * The device is not prepared for use - this is an internal function.
 790  * The function uclass_get_device_tail() can be used to probe the device.
 791  *
 792  * Note that some devices are considered removable until they have been probed
 793  *
 794  * @return 0 if found, -ENODEV if not found
 795  */
 796 int blk_find_first(enum blk_flag_t flags, struct udevice **devp);
 797
 798 /**
 799  * blk_find_next() - Return the next matching block device
 800  * @flags: Indicates type of device to return
 801  * @devp: On entry, pointer to device to lookup. On exit, returns pointer
 802  * to the next device in the same uclass, or NULL if none
 803  *
 804  * The device is not prepared for use - this is an internal function.
 805  * The function uclass_get_device_tail() can be used to probe the device.
 806  *
 807  * Note that some devices are considered removable until they have been probed
 808  *
 809  * @return 0 if found, -ENODEV if not found
 810  */
 811 int blk_find_next(enum blk_flag_t flags, struct udevice **devp);
 812
 813 /**
 814  * blk_foreach() - iterate through block devices
 815  *
 816  * This creates a for() loop which works through the available block devices in
 817  * order from start to end.
 818  *
 819  * If for some reason the uclass cannot be found, this does nothing.
 820  *
 821  * @_flags: Indicates type of device to return
 822  * @_pos: struct udevice * to hold the current device. Set to NULL when there
 823  * are no more devices.
 824  */
 825 #define blk_foreach(_flags, _pos) \
 826         for (int _ret = blk_find_first(_flags, &_pos); !_ret && _pos; \
 827              _ret = blk_find_next(_flags, &_pos))
 828
 829 /**
 830  * blk_foreach_probe() - Helper function to iteration through block devices
 831  *
 832  * This creates a for() loop which works through the available devices in
 833  * a uclass in order from start to end. Devices are probed if necessary,
 834  * and ready for use.
 835  *
 836  * @flags: Indicates type of device to return
 837  * @dev: struct udevice * to hold the current device. Set to NULL when there
 838  * are no more devices.
 839  */
 840 #define blk_foreach_probe(flags, pos)   \
 841         for (int _ret = blk_first_device_err(flags, &(pos)); \
 842              !_ret && pos; \
 843              _ret = blk_next_device_err(flags, &(pos)))
 844
 845 /**
 846  * blk_count_devices() - count the number of devices of a particular type
 847  *
 848  * @flags: Indicates type of device to find
 849  * Return: number of devices matching those flags
 850  */
 851 int blk_count_devices(enum blk_flag_t flag);
 852
 853 #endif