1config DM_SERIAL 2 bool "Enable Driver Model for serial drivers" 3 depends on DM 4 help 5 Enable driver model for serial. This replaces 6 drivers/serial/serial.c with the serial uclass, which 7 implements serial_putc() etc. The uclass interface is 8 defined in include/serial.h. 9 10config DEBUG_UART 11 bool "Enable an early debug UART for debugging" 12 help 13 The debug UART is intended for use very early in U-Boot to debug 14 problems when an ICE or other debug mechanism is not available. 15 16 To use it you should: 17 - Make sure your UART supports this interface 18 - Enable CONFIG_DEBUG_UART 19 - Enable the CONFIG for your UART to tell it to provide this interface 20 (e.g. CONFIG_DEBUG_UART_NS16550) 21 - Define the required settings as needed (see below) 22 - Call debug_uart_init() before use 23 - Call debug_uart_putc() to output a character 24 25 Depending on your platform it may be possible to use this UART before 26 a stack is available. 27 28 If your UART does not support this interface you can probably add 29 support quite easily. Remember that you cannot use driver model and 30 it is preferred to use no stack. 31 32 You must not use this UART once driver model is working and the 33 serial drivers are up and running (done in serial_init()). Otherwise 34 the drivers may conflict and you will get strange output. 35 36choice 37 prompt "Select which UART will provide the debug UART" 38 depends on DEBUG_UART 39 40config DEBUG_UART_NS16550 41 bool "ns16550" 42 help 43 Select this to enable a debug UART using the ns16550 driver. You 44 will need to provide parameters to make this work. The driver will 45 be available until the real driver model serial is running. 46 47config DEBUG_EFI_CONSOLE 48 bool "EFI" 49 depends on EFI_APP 50 help 51 Select this to enable a debug console which calls back to EFI to 52 output to the console. This can be useful for early debugging of 53 U-Boot when running on top of EFI (Extensive Firmware Interface). 54 This is a type of BIOS used by PCs. 55 56endchoice 57 58config DEBUG_UART_BASE 59 hex "Base address of UART" 60 depends on DEBUG_UART 61 help 62 This is the base address of your UART for memory-mapped UARTs. 63 64 A default should be provided by your board, but if not you will need 65 to use the correct value here. 66 67config DEBUG_UART_CLOCK 68 int "UART input clock" 69 depends on DEBUG_UART 70 help 71 The UART input clock determines the speed of the internal UART 72 circuitry. The baud rate is derived from this by dividing the input 73 clock down. 74 75 A default should be provided by your board, but if not you will need 76 to use the correct value here. 77 78config DEBUG_UART_SHIFT 79 int "UART register shift" 80 depends on DEBUG_UART 81 default 0 if DEBUG_UART 82 help 83 Some UARTs (notably ns16550) support different register layouts 84 where the registers are spaced either as bytes, words or some other 85 value. Use this value to specify the shift to use, where 0=byte 86 registers, 2=32-bit word registers, etc. 87 88config SANDBOX_SERIAL 89 bool "Sandbox UART support" 90 depends on SANDBOX && DM 91 help 92 Select this to enable a seral UART for sandbox. This is required to 93 operate correctly, otherwise you will see no serial output from 94 sandbox. The emulated UART will display to the console and console 95 input will be fed into the UART. This allows you to interact with 96 U-Boot. 97 98 The operation of the console is controlled by the -t command-line 99 flag. In raw mode, U-Boot sees all characters from the terminal 100 before they are processed, including Ctrl-C. In cooked mode, Ctrl-C 101 is processed by the terminal, and terminates U-Boot. Valid options 102 are: 103 104 -t raw-with-sigs Raw mode, Ctrl-C will terminate U-Boot 105 -t raw Raw mode, Ctrl-C is processed by U-Boot 106 -t cooked Cooked mode, Ctrl-C terminates 107 108config UNIPHIER_SERIAL 109 bool "Support for UniPhier on-chip UART" 110 depends on ARCH_UNIPHIER && DM_SERIAL 111 help 112 If you have a UniPhier based board and want to use the on-chip 113 serial ports, say Y to this option. If unsure, say N. 114 115config X86_SERIAL 116 bool "Support for 16550 serial port on x86 machines" 117 depends on X86 118 default y 119 help 120 Most x86 machines have a ns16550 UART or compatible. This can be 121 enabled in the device tree with the correct input clock frequency 122 provided (default 1843200). Enable this to obtain serial console 123 output. 124