1config DM 2 bool "Enable Driver Model" 3 help 4 This config option enables Driver Model. This brings in the core 5 support, including scanning of platform data on start-up. If 6 CONFIG_OF_CONTROL is enabled, the device tree will be scanned also 7 when available. 8 9config SPL_DM 10 bool "Enable Driver Model for SPL" 11 depends on DM && SPL 12 help 13 Enable driver model in SPL. You will need to provide a 14 suitable malloc() implementation. If you are not using the 15 full malloc() enabled by CONFIG_SYS_SPL_MALLOC_START, 16 consider using CONFIG_SYS_MALLOC_SIMPLE. In that case you 17 must provide CONFIG_SYS_MALLOC_F_LEN to set the size. 18 In most cases driver model will only allocate a few uclasses 19 and devices in SPL, so 1KB should be enable. See 20 CONFIG_SYS_MALLOC_F_LEN for more details on how to enable it. 21 22config DM_WARN 23 bool "Enable warnings in driver model" 24 depends on DM 25 default y 26 help 27 The dm_warn() function can use up quite a bit of space for its 28 strings. By default this is disabled for SPL builds to save space. 29 This will cause dm_warn() to be compiled out - it will do nothing 30 when called. 31 32config DM_DEVICE_REMOVE 33 bool "Support device removal" 34 depends on DM 35 default y 36 help 37 We can save some code space by dropping support for removing a 38 device. This is not normally required in SPL, so by default this 39 option is disabled for SPL. 40 41 Note that this may have undesirable results in the USB subsystem as 42 it causes unplugged devices to linger around in the dm-tree, and it 43 causes USB host controllers to not be stopped when booting the OS. 44 45config DM_STDIO 46 bool "Support stdio registration" 47 depends on DM 48 default y 49 help 50 Normally serial drivers register with stdio so that they can be used 51 as normal output devices. In SPL we don't normally use stdio, so 52 we can omit this feature. 53 54config DM_SEQ_ALIAS 55 bool "Support numbered aliases in device tree" 56 depends on DM 57 default y 58 help 59 Most boards will have a '/aliases' node containing the path to 60 numbered devices (e.g. serial0 = &serial0). This feature can be 61 disabled if it is not required, to save code space in SPL. 62 63config REGMAP 64 bool "Support register maps" 65 depends on DM 66 help 67 Hardware peripherals tend to have one or more sets of registers 68 which can be accessed to control the hardware. A register map 69 models this with a simple read/write interface. It can in principle 70 support any bus type (I2C, SPI) but so far this only supports 71 direct memory access. 72 73config SYSCON 74 bool "Support system controllers" 75 depends on REGMAP 76 help 77 Many SoCs have a number of system controllers which are dealt with 78 as a group by a single driver. Some common functionality is provided 79 by this uclass, including accessing registers via regmap and 80 assigning a unique number to each. 81 82config DEVRES 83 bool "Managed device resources" 84 depends on DM 85 help 86 This option enables the Managed device resources core support. 87 Device resources managed by the devres framework are automatically 88 released whether initialization fails half-way or the device gets 89 detached. 90 91 If this option is disabled, devres functions fall back to 92 non-managed variants. For example, devres_alloc() to kzalloc(), 93 devm_kmalloc() to kmalloc(), etc. 94 95config DEBUG_DEVRES 96 bool "Managed device resources debugging functions" 97 depends on DEVRES 98 help 99 If this option is enabled, devres debug messages are printed. 100 Also, a function is available to dump a list of device resources. 101 Select this if you are having a problem with devres or want to 102 debug resource management for a managed device. 103 104 If you are unsure about this, Say N here. 105