1config BLK 2 bool "Support block devices" 3 depends on DM 4 default y if DM_MMC 5 help 6 Enable support for block devices, such as SCSI, MMC and USB 7 flash sticks. These provide a block-level interface which permits 8 reading, writing and (in some cases) erasing blocks. Block 9 devices often have a partition table which allows the device to 10 be partitioned into several areas, called 'partitions' in U-Boot. 11 A filesystem can be placed in each partition. 12 13config BLOCK_CACHE 14 bool "Use block device cache" 15 default n 16 help 17 This option enables a disk-block cache for all block devices. 18 This is most useful when accessing filesystems under U-Boot since 19 it will prevent repeated reads from directory structures and other 20 filesystem data structures. 21 22config IDE 23 bool "Support IDE controllers" 24 help 25 Enables support for IDE (Integrated Drive Electronics) hard drives. 26 This allows access to raw blocks and filesystems on an IDE drive 27 from U-Boot. See also CMD_IDE which provides an 'ide' command for 28 performing various IDE operations. 29