[U-Boot] [PATCH] serial: Add vcth UART driver

Stefan Roese sr at denx.de
Wed Nov 12 13:30:10 CET 2008


This patch adds the UART driver for the upcoming VCTH board support.

Signed-off-by: Stefan Roese <sr at denx.de>
---
 drivers/serial/Makefile |    1 +
 drivers/serial/vcth.c   |  121 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 122 insertions(+), 0 deletions(-)
 create mode 100755 drivers/serial/vcth.c

diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index eafe543..17235ff 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -38,6 +38,7 @@ COBJS-$(CONFIG_PL011_SERIAL) += serial_pl01x.o
 COBJS-$(CONFIG_XILINX_UARTLITE) += serial_xuartlite.o
 COBJS-$(CONFIG_SCIF_CONSOLE) += serial_sh.o
 COBJS-$(CONFIG_USB_TTY) += usbtty.o
+COBJS-$(CONFIG_VCTH_SERIAL) += vcth.o
 
 COBJS	:= $(sort $(COBJS-y))
 SRCS	:= $(COBJS:.o=.c)
diff --git a/drivers/serial/vcth.c b/drivers/serial/vcth.c
new file mode 100755
index 0000000..2c847d0
--- /dev/null
+++ b/drivers/serial/vcth.c
@@ -0,0 +1,121 @@
+/*
+ * (C) Copyright 2008 Stefan Roese <sr at denx.de>, DENX Software Engineering
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <config.h>
+#include <common.h>
+#include <asm/io.h>
+
+#define UART_1_BASE		0xBF89C000
+
+#define	UART_RBR_OFF		0x00	/* receiver buffer reg		*/
+#define	UART_THR_OFF		0x00	/* transmit holding  reg	*/
+#define	UART_DLL_OFF		0x00	/* divisor latch low reg	*/
+#define	UART_IER_OFF		0x04	/* interrupt enable reg		*/
+#define	UART_DLH_OFF		0x04	/* receiver buffer reg		*/
+#define	UART_FCR_OFF		0x08	/* fifo control register	*/
+#define	UART_LCR_OFF		0x0c	/* line control register	*/
+#define	UART_MCR_OFF		0x10	/* modem control register	*/
+#define	UART_LSR_OFF		0x14	/* line status register		*/
+#define	UART_MSR_OFF		0x18	/* modem status register	*/
+#define	UART_SCR_OFF		0x1c	/* scratch pad register		*/
+
+#define UART_RCV_DATA_RDY	0x01	/* Data Received		*/
+#define UART_XMT_HOLD_EMPTY	0x20
+#define UART_TRANSMIT_EMPTY	0x40
+
+/* 7 bit on line control reg. enalbing rw to dll and dlh */
+#define UART_LCR_DLAB		0x0080
+
+#define UART___9600_BDR		0x84
+#define UART__19200_BDR		0x42
+#define UART_115200_BDR		0x08
+
+#define UART_DIS_ALL_INTER	0x00	/* disable all interrupts	*/
+
+#define UART_5DATA_BITS		0x0000	/*   5 [bits]  1.5 bits   2	*/
+#define UART_6DATA_BITS		0x0001	/*   6 [bits]  1   bits   2	*/
+#define UART_7DATA_BITS		0x0002	/*   7 [bits]  1   bits   2	*/
+#define UART_8DATA_BITS		0x0003	/*   8 [bits]  1   bits   2	*/
+
+static void vcth_uart_set_baud_rate(u32 address, u32 dh, u32 dl)
+{
+	u32 val = __raw_readl(UART_1_BASE + UART_LCR_OFF);
+
+	/* set 7 bit on 1 */
+	val |= UART_LCR_DLAB;
+	__raw_writel(val, UART_1_BASE + UART_LCR_OFF);
+
+	__raw_writel(dl, UART_1_BASE + UART_DLL_OFF);
+	__raw_writel(dh, UART_1_BASE + UART_DLH_OFF);
+
+	/* set 7 bit on 0 */
+	val &= ~UART_LCR_DLAB;
+	__raw_writel(val, UART_1_BASE + UART_LCR_OFF);
+
+	return;
+}
+
+int serial_init(void)
+{
+	__raw_writel(UART_DIS_ALL_INTER, UART_1_BASE + UART_IER_OFF);
+	vcth_uart_set_baud_rate(UART_1_BASE, 0, UART_115200_BDR);
+	__raw_writel(UART_8DATA_BITS, UART_1_BASE + UART_LCR_OFF);
+
+	return 0;
+}
+
+void serial_setbrg(void)
+{
+	/*
+	 * Baudrate change not supported currently, fixed to 115200 baud
+	 */
+}
+
+void serial_putc(const char c)
+{
+	if (c == '\n')
+		serial_putc('\r');
+
+	while (!(UART_XMT_HOLD_EMPTY & __raw_readl(UART_1_BASE + UART_LSR_OFF)))
+		;
+
+	__raw_writel(c, UART_1_BASE + UART_THR_OFF);
+}
+
+void serial_puts(const char *s)
+{
+	while (*s)
+		serial_putc(*s++);
+}
+
+int serial_getc(void)
+{
+	while (!(UART_RCV_DATA_RDY & __raw_readl(UART_1_BASE + UART_LSR_OFF)))
+		;
+
+	return __raw_readl(UART_1_BASE + UART_RBR_OFF) & 0xff;
+}
+
+int serial_tstc(void)
+{
+	if (!(UART_RCV_DATA_RDY & __raw_readl(UART_1_BASE + UART_LSR_OFF)))
+		return 0;
+
+	return 1;
+}
-- 
1.6.0.4



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