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
diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
index 67b1d60..362f2ee 100644
--- a/drivers/serial/ns16550.c
+++ b/drivers/serial/ns16550.c
@@ -254,15 +254,20 @@
*/
baud_divisor = calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
CONFIG_BAUDRATE);
+ baud_divisor = 13;
+ serial_out_shift(&com_port->ier, CONFIG_DEBUG_UART_SHIFT,
+ CONFIG_SYS_NS16550_IER);
+ serial_out_shift(&com_port->mcr, CONFIG_DEBUG_UART_SHIFT, UART_MCRVAL);
+ serial_out_shift(&com_port->fcr, CONFIG_DEBUG_UART_SHIFT, UART_FCRVAL);
- serial_out_shift(&com_port->ier, 0, CONFIG_SYS_NS16550_IER);
- serial_out_shift(&com_port->mcr, 0, UART_MCRVAL);
- serial_out_shift(&com_port->fcr, 0, UART_FCRVAL);
-
- serial_out_shift(&com_port->lcr, 0, UART_LCR_BKSE | UART_LCRVAL);
- serial_out_shift(&com_port->dll, 0, baud_divisor & 0xff);
- serial_out_shift(&com_port->dlm, 0, (baud_divisor >> 8) & 0xff);
- serial_out_shift(&com_port->lcr, 0, UART_LCRVAL);
+ serial_out_shift(&com_port->lcr, CONFIG_DEBUG_UART_SHIFT,
+ UART_LCR_BKSE | UART_LCRVAL);
+ serial_out_shift(&com_port->dll, CONFIG_DEBUG_UART_SHIFT,
+ baud_divisor & 0xff);
+ serial_out_shift(&com_port->dlm, CONFIG_DEBUG_UART_SHIFT,
+ (baud_divisor >> 8) & 0xff);
+ serial_out_shift(&com_port->lcr, CONFIG_DEBUG_UART_SHIFT,
+ UART_LCRVAL);
}
static inline void _debug_uart_putc(int ch)
@@ -271,7 +276,7 @@
while (!(serial_in_shift(&com_port->lsr, 0) & UART_LSR_THRE))
;
- serial_out_shift(&com_port->thr, 0, ch);
+ serial_out_shift(&com_port->thr, CONFIG_DEBUG_UART_SHIFT, ch);
}
DEBUG_UART_FUNCS