serial: ns16550: Add RX interrupt buffer support
Pasting longer lines into the U-Boot console prompt sometimes leads to
characters missing. One problem here is the small 16-byte FIFO of the
legacy NS16550 UART, e.g. on x86 platforms.
This patch now introduces a Kconfig option to enable RX interrupt
buffer support for NS16550 style UARTs. With this option enabled, I was
able paste really long lines into the U-Boot console, without any
characters missing.
Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Cc: Bin Meng <bmeng.cn@gmail.com>
[trini: Guard ns16550_serial_remove with
CONFIG_IS_ENABLED(SERIAL_PRESENT) to match struct assignment]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/include/ns16550.h b/include/ns16550.h
index 5fcbcd2..7e9944d 100644
--- a/include/ns16550.h
+++ b/include/ns16550.h
@@ -51,6 +51,10 @@
* @base: Base register address
* @reg_shift: Shift size of registers (0=byte, 1=16bit, 2=32bit...)
* @clock: UART base clock speed in Hz
+ *
+ * @buf: Pointer to the RX interrupt buffer
+ * @rd_ptr: Read pointer in the RX interrupt buffer
+ * @wr_ptr: Write pointer in the RX interrupt buffer
*/
struct ns16550_platdata {
unsigned long base;
@@ -58,6 +62,12 @@
int clock;
int reg_offset;
u32 fcr;
+
+ int irq;
+
+ char *buf;
+ int rd_ptr;
+ int wr_ptr;
};
struct udevice;