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 HAVE_BLOCK_DEVICE 14 bool "Enable Legacy Block Device" 15 help 16 Some devices require block support whether or not DM is enabled 17 18config SPL_BLK 19 bool "Support block devices in SPL" 20 depends on SPL_DM && BLK 21 default y 22 help 23 Enable support for block devices, such as SCSI, MMC and USB 24 flash sticks. These provide a block-level interface which permits 25 reading, writing and (in some cases) erasing blocks. Block 26 devices often have a partition table which allows the device to 27 be partitioned into several areas, called 'partitions' in U-Boot. 28 A filesystem can be placed in each partition. 29 30config BLOCK_CACHE 31 bool "Use block device cache" 32 depends on BLK 33 default y 34 help 35 This option enables a disk-block cache for all block devices. 36 This is most useful when accessing filesystems under U-Boot since 37 it will prevent repeated reads from directory structures and other 38 filesystem data structures. 39 40config SPL_BLOCK_CACHE 41 bool "Use block device cache in SPL" 42 depends on SPL_BLK 43 default n 44 help 45 This option enables the disk-block cache in SPL 46 47config IDE 48 bool "Support IDE controllers" 49 select HAVE_BLOCK_DEVICE 50 help 51 Enables support for IDE (Integrated Drive Electronics) hard drives. 52 This allows access to raw blocks and filesystems on an IDE drive 53 from U-Boot. See also CMD_IDE which provides an 'ide' command for 54 performing various IDE operations. 55