serial: ns16550: Add an option to specify the debug UART register shift
This UART permits different register spacing. To support the debug UART on
devices which have a spacing other than 1 byte, allow the shift value to
be specified.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 1686a1f..54e6f26 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -66,6 +66,16 @@
A default should be provided by your board, but if not you will need
to use the correct value here.
+config DEBUG_UART_SHIFT
+ int "UART register shift"
+ depends on DEBUG_UART
+ default 0 if DEBUG_UART
+ help
+ Some UARTs (notably ns16550) support different register layouts
+ where the registers are spaced either as bytes, words or some other
+ value. Use this value to specify the shift to use, where 0=byte
+ registers, 2=32-bit word registers, etc.
+
config UNIPHIER_SERIAL
bool "UniPhier on-chip UART support"
depends on ARCH_UNIPHIER && DM_SERIAL