xref: /openbmc/u-boot/drivers/serial/Kconfig (revision aefb8f4c)
1#
2# Serial device configuration
3#
4
5menu "Serial drivers"
6
7config REQUIRE_SERIAL_CONSOLE
8	bool "Require a serial port for console"
9	# Running without a serial console is not supported by the
10	# non-dm serial code
11	depends on DM_SERIAL
12	default y
13	help
14	  Require a serial port for the console, and panic if none is found
15	  during serial port initialization (default y). Set this to n on
16	  boards which have no debug serial port whatsoever.
17
18config SERIAL_PRESENT
19	bool "Provide a serial driver"
20	depends on DM_SERIAL
21	default y
22	help
23	  In very space-constrained devices even the full UART driver is too
24	  large. In this case the debug UART can still be used in some cases.
25	  This option enables the full UART in U-Boot, so if is it disabled,
26	  the full UART driver will be omitted, thus saving space.
27
28config SPL_SERIAL_PRESENT
29	bool "Provide a serial driver in SPL"
30	depends on DM_SERIAL
31	default y
32	help
33	  In very space-constrained devices even the full UART driver is too
34	  large. In this case the debug UART can still be used in some cases.
35	  This option enables the full UART in SPL, so if is it disabled,
36	  the full UART driver will be omitted, thus saving space.
37
38config DM_SERIAL
39	bool "Enable Driver Model for serial drivers"
40	depends on DM
41	help
42	  Enable driver model for serial. This replaces
43	  drivers/serial/serial.c with the serial uclass, which
44	  implements serial_putc() etc. The uclass interface is
45	  defined in include/serial.h.
46
47config DEBUG_UART
48	bool "Enable an early debug UART for debugging"
49	help
50	  The debug UART is intended for use very early in U-Boot to debug
51	  problems when an ICE or other debug mechanism is not available.
52
53	  To use it you should:
54	  - Make sure your UART supports this interface
55	  - Enable CONFIG_DEBUG_UART
56	  - Enable the CONFIG for your UART to tell it to provide this interface
57	        (e.g. CONFIG_DEBUG_UART_NS16550)
58	  - Define the required settings as needed (see below)
59	  - Call debug_uart_init() before use
60	  - Call debug_uart_putc() to output a character
61
62	  Depending on your platform it may be possible to use this UART before
63	  a stack is available.
64
65	  If your UART does not support this interface you can probably add
66	  support quite easily. Remember that you cannot use driver model and
67	  it is preferred to use no stack.
68
69	  You must not use this UART once driver model is working and the
70	  serial drivers are up and running (done in serial_init()). Otherwise
71	  the drivers may conflict and you will get strange output.
72
73choice
74	prompt "Select which UART will provide the debug UART"
75	depends on DEBUG_UART
76	default DEBUG_UART_NS16550
77
78config DEBUG_UART_ALTERA_JTAGUART
79	bool "Altera JTAG UART"
80	help
81	  Select this to enable a debug UART using the altera_jtag_uart driver.
82	  You will need to provide parameters to make this work. The driver will
83	  be available until the real driver model serial is running.
84
85config DEBUG_UART_ALTERA_UART
86	bool "Altera UART"
87	help
88	  Select this to enable a debug UART using the altera_uart driver.
89	  You will need to provide parameters to make this work. The driver will
90	  be available until the real driver model serial is running.
91
92config DEBUG_UART_NS16550
93	bool "ns16550"
94	help
95	  Select this to enable a debug UART using the ns16550 driver. You
96	  will need to provide parameters to make this work. The driver will
97	  be available until the real driver model serial is running.
98
99config DEBUG_EFI_CONSOLE
100	bool "EFI"
101	depends on EFI_APP
102	help
103	  Select this to enable a debug console which calls back to EFI to
104	  output to the console. This can be useful for early debugging of
105	  U-Boot when running on top of EFI (Extensive Firmware Interface).
106	  This is a type of BIOS used by PCs.
107
108config DEBUG_UART_S5P
109	bool "Samsung S5P"
110	help
111	  Select this to enable a debug UART using the serial_s5p driver. You
112	  will need to provide parameters to make this work. The driver will
113	  be available until the real driver-model serial is running.
114
115config DEBUG_UART_ZYNQ
116	bool "Xilinx Zynq"
117	help
118	  Select this to enable a debug UART using the serial_zynq driver. You
119	  will need to provide parameters to make this work. The driver will
120	  be available until the real driver-model serial is running.
121
122config DEBUG_UART_APBUART
123	depends on LEON3
124	bool "Gaisler APBUART"
125	help
126	  Select this to enable a debug UART using the serial_leon3 driver. You
127	  will need to provide parameters to make this work. The driver will
128	  be available until the real driver model serial is running.
129
130endchoice
131
132config DEBUG_UART_BASE
133	hex "Base address of UART"
134	depends on DEBUG_UART
135	help
136	  This is the base address of your UART for memory-mapped UARTs.
137
138	  A default should be provided by your board, but if not you will need
139	  to use the correct value here.
140
141config DEBUG_UART_CLOCK
142	int "UART input clock"
143	depends on DEBUG_UART
144	help
145	  The UART input clock determines the speed of the internal UART
146	  circuitry. The baud rate is derived from this by dividing the input
147	  clock down.
148
149	  A default should be provided by your board, but if not you will need
150	  to use the correct value here.
151
152config DEBUG_UART_SHIFT
153	int "UART register shift"
154	depends on DEBUG_UART
155	default 0 if DEBUG_UART
156	help
157	  Some UARTs (notably ns16550) support different register layouts
158	  where the registers are spaced either as bytes, words or some other
159	  value. Use this value to specify the shift to use, where 0=byte
160	  registers, 2=32-bit word registers, etc.
161
162config DEBUG_UART_BOARD_INIT
163	bool "Enable board-specific debug UART init"
164	depends on DEBUG_UART
165	help
166	  Some boards need to set things up before the debug UART can be used.
167	  On these boards a call to debug_uart_init() is insufficient. When
168	  this option is enabled, the function board_debug_uart_init() will
169	  be called when debug_uart_init() is called. You can put any code
170	  here that is needed to set up the UART ready for use, such as set
171	  pin multiplexing or enable clocks.
172
173config DEBUG_UART_ANNOUNCE
174	bool "Show a message when the debug UART starts up"
175	depends on DEBUG_UART
176	help
177	  Enable this option to show a message when the debug UART is ready
178	  for use. You will see a message like "<debug_uart> " as soon as
179	  U-Boot has the UART ready for use (i.e. your code calls
180	  debug_uart_init()). This can be useful just as a check that
181	  everything is working.
182
183config ALTERA_JTAG_UART
184	bool "Altera JTAG UART support"
185	depends on DM_SERIAL
186	help
187	  Select this to enable an JTAG UART for Altera devices.The JTAG UART
188	  core implements a method to communicate serial character streams
189	  between a host PC and a Qsys system on an Altera FPGA. Please find
190	  details on the "Embedded Peripherals IP User Guide" of Altera.
191
192config ALTERA_JTAG_UART_BYPASS
193	bool "Bypass output when no connection"
194	depends on ALTERA_JTAG_UART
195	help
196	  Bypass console output and keep going even if there is no JTAG
197	  terminal connection with the host. The console output will resume
198	  once the JTAG terminal is connected. Without the bypass, the console
199	  output will wait forever until a JTAG terminal is connected. If you
200	  not are sure, say Y.
201
202config ALTERA_UART
203	bool "Altera UART support"
204	depends on DM_SERIAL
205	help
206	  Select this to enable an UART for Altera devices. Please find
207	  details on the "Embedded Peripherals IP User Guide" of Altera.
208
209config SYS_NS16550
210	bool "NS16550 UART or compatible"
211	help
212	  Support NS16550 UART or compatible. This can be enabled in the
213	  device tree with the correct input clock frequency. If the input
214	  clock frequency is not defined in the device tree, the macro
215	  CONFIG_SYS_NS16550_CLK defined in a legacy board header file will
216	  be used. It can be a constant or a function to get clock, eg,
217	  get_serial_clock().
218
219config SANDBOX_SERIAL
220	bool "Sandbox UART support"
221	depends on SANDBOX
222	help
223	  Select this to enable a seral UART for sandbox. This is required to
224	  operate correctly, otherwise you will see no serial output from
225	  sandbox. The emulated UART will display to the console and console
226	  input will be fed into the UART. This allows you to interact with
227	  U-Boot.
228
229	  The operation of the console is controlled by the -t command-line
230	  flag. In raw mode, U-Boot sees all characters from the terminal
231	  before they are processed, including Ctrl-C. In cooked mode, Ctrl-C
232	  is processed by the terminal, and terminates U-Boot. Valid options
233	  are:
234
235	     -t raw-with-sigs	Raw mode, Ctrl-C will terminate U-Boot
236	     -t raw		Raw mode, Ctrl-C is processed by U-Boot
237	     -t cooked		Cooked mode, Ctrl-C terminates
238
239config UNIPHIER_SERIAL
240	bool "Support for UniPhier on-chip UART"
241	depends on ARCH_UNIPHIER
242	help
243	  If you have a UniPhier based board and want to use the on-chip
244	  serial ports, say Y to this option. If unsure, say N.
245
246endmenu
247