serial: omap: Support debug UART
Add debug UART functions to permit omap specific ns16550 to
provide an early debug UART. This is mostly in common with
DEBUG_UART_NS16550 except for Mode definition register which
is required for selecting UART mode(16x auto-baud or 13x mode).
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 7249945..58fc7cd 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -257,6 +257,13 @@
driver will be available until the real driver-model serial is
running.
+config DEBUG_UART_OMAP
+ bool "OMAP uart"
+ help
+ Select this to enable a debug UART using the omap ns16550 driver.
+ You will need to provide parameters to make this work. The driver
+ will be available until the real driver model serial is running.
+
endchoice
config DEBUG_UART_BASE
diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
index 4f86780..ca55df7 100644
--- a/drivers/serial/ns16550.c
+++ b/drivers/serial/ns16550.c
@@ -246,17 +246,6 @@
#include <debug_uart.h>
-#define serial_dout(reg, value) \
- serial_out_shift((char *)com_port + \
- ((char *)reg - (char *)com_port) * \
- (1 << CONFIG_DEBUG_UART_SHIFT), \
- CONFIG_DEBUG_UART_SHIFT, value)
-#define serial_din(reg) \
- serial_in_shift((char *)com_port + \
- ((char *)reg - (char *)com_port) * \
- (1 << CONFIG_DEBUG_UART_SHIFT), \
- CONFIG_DEBUG_UART_SHIFT)
-
static inline void _debug_uart_init(void)
{
struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
@@ -271,6 +260,41 @@
baud_divisor = ns16550_calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
CONFIG_BAUDRATE);
serial_dout(&com_port->ier, CONFIG_SYS_NS16550_IER);
+ serial_dout(&com_port->mcr, UART_MCRVAL);
+ serial_dout(&com_port->fcr, UART_FCR_DEFVAL);
+
+ serial_dout(&com_port->lcr, UART_LCR_BKSE | UART_LCRVAL);
+ serial_dout(&com_port->dll, baud_divisor & 0xff);
+ serial_dout(&com_port->dlm, (baud_divisor >> 8) & 0xff);
+ serial_dout(&com_port->lcr, UART_LCRVAL);
+}
+
+static inline void _debug_uart_putc(int ch)
+{
+ struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
+
+ while (!(serial_din(&com_port->lsr) & UART_LSR_THRE))
+ ;
+ serial_dout(&com_port->thr, ch);
+}
+
+DEBUG_UART_FUNCS
+
+#endif
+
+#ifdef CONFIG_DEBUG_UART_OMAP
+
+#include <debug_uart.h>
+
+static inline void _debug_uart_init(void)
+{
+ struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
+ int baud_divisor;
+
+ baud_divisor = ns16550_calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
+ CONFIG_BAUDRATE);
+ serial_dout(&com_port->ier, CONFIG_SYS_NS16550_IER);
+ serial_dout(&com_port->mdr1, 0x7);
serial_dout(&com_port->mcr, UART_MCRVAL);
serial_dout(&com_port->fcr, UART_FCR_DEFVAL);
@@ -278,6 +302,7 @@
serial_dout(&com_port->dll, baud_divisor & 0xff);
serial_dout(&com_port->dlm, (baud_divisor >> 8) & 0xff);
serial_dout(&com_port->lcr, UART_LCRVAL);
+ serial_dout(&com_port->mdr1, 0x0);
}
static inline void _debug_uart_putc(int ch)
diff --git a/include/debug_uart.h b/include/debug_uart.h
index 2980ae6..6f0b0c5 100644
--- a/include/debug_uart.h
+++ b/include/debug_uart.h
@@ -111,6 +111,17 @@
#define _DEBUG_UART_ANNOUNCE
#endif
+#define serial_dout(reg, value) \
+ serial_out_shift((char *)com_port + \
+ ((char *)reg - (char *)com_port) * \
+ (1 << CONFIG_DEBUG_UART_SHIFT), \
+ CONFIG_DEBUG_UART_SHIFT, value)
+#define serial_din(reg) \
+ serial_in_shift((char *)com_port + \
+ ((char *)reg - (char *)com_port) * \
+ (1 << CONFIG_DEBUG_UART_SHIFT), \
+ CONFIG_DEBUG_UART_SHIFT)
+
/*
* Now define some functions - this should be inserted into the serial driver
*/