[PATCH] Nios2: Add Altera UART driver

[franck.jullien at gmail.com]

From: Franck JULLIEN <franck.jullien at gmail.com>

---
 drivers/serial/Kconfig         |    5 ++
 drivers/serial/Makefile        |   25 +++++-----
 drivers/serial/serial_altera.c |   97 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 115 insertions(+), 12 deletions(-)
 create mode 100644 drivers/serial/serial_altera.c

diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index ffd877a..9e05f4b 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -43,6 +43,11 @@ config DRIVER_SERIAL_BLACKFIN
 	default y
 	bool "Blackfin serial driver"
 
+config DRIVER_SERIAL_ALTERA
+	depends on NIOS2
+	default y
+	bool "Altera serial driver"
+
 config DRIVER_SERIAL_NS16550
 	default n
 	bool "NS16550 serial driver"
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index 9f0e12b..8067b74 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -4,15 +4,16 @@
 # serial_max3100.o
 # serial_pl010.o
 # serial_xuartlite.o
-obj-$(CONFIG_DRIVER_SERIAL_ARM_DCC)		+= arm_dcc.o
-obj-$(CONFIG_SERIAL_AMBA_PL011) += amba-pl011.o
-obj-$(CONFIG_DRIVER_SERIAL_IMX)			+= serial_imx.o
-obj-$(CONFIG_DRIVER_SERIAL_STM378X)		+= stm-serial.o
-obj-$(CONFIG_DRIVER_SERIAL_ATMEL)		+= atmel.o
-obj-$(CONFIG_DRIVER_SERIAL_NETX)		+= serial_netx.o
-obj-$(CONFIG_DRIVER_SERIAL_LINUX_COMSOLE)	+= linux_console.o
-obj-$(CONFIG_DRIVER_SERIAL_MPC5XXX)		+= serial_mpc5xxx.o
-obj-$(CONFIG_DRIVER_SERIAL_BLACKFIN)		+= serial_blackfin.o
-obj-$(CONFIG_DRIVER_SERIAL_NS16550)		+= serial_ns16550.o
-obj-$(CONFIG_DRIVER_SERIAL_PL010)		+= serial_pl010.o
-obj-$(CONFIG_DRIVER_SERIAL_S3C24X0)		+= serial_s3c24x0.o
+obj-$(CONFIG_DRIVER_SERIAL_ARM_DCC)             += arm_dcc.o
+obj-$(CONFIG_SERIAL_AMBA_PL011)                 += amba-pl011.o
+obj-$(CONFIG_DRIVER_SERIAL_IMX)                 += serial_imx.o
+obj-$(CONFIG_DRIVER_SERIAL_STM378X)             += stm-serial.o
+obj-$(CONFIG_DRIVER_SERIAL_ATMEL)               += atmel.o
+obj-$(CONFIG_DRIVER_SERIAL_NETX)                += serial_netx.o
+obj-$(CONFIG_DRIVER_SERIAL_LINUX_COMSOLE)       += linux_console.o
+obj-$(CONFIG_DRIVER_SERIAL_MPC5XXX)             += serial_mpc5xxx.o
+obj-$(CONFIG_DRIVER_SERIAL_BLACKFIN)            += serial_blackfin.o
+obj-$(CONFIG_DRIVER_SERIAL_NS16550)             += serial_ns16550.o
+obj-$(CONFIG_DRIVER_SERIAL_PL010)               += serial_pl010.o
+obj-$(CONFIG_DRIVER_SERIAL_S3C24X0)             += serial_s3c24x0.o
+obj-$(CONFIG_DRIVER_SERIAL_ALTERA)              += serial_altera.o
diff --git a/drivers/serial/serial_altera.c b/drivers/serial/serial_altera.c
new file mode 100644
index 0000000..03e48d1
--- /dev/null
+++ b/drivers/serial/serial_altera.c
@@ -0,0 +1,97 @@
+/*
+ * (C) Copyright 2011, Franck JULLIEN, <elec4fun at gmail.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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 <common.h>
+#include <driver.h>
+#include <init.h>
+#include <malloc.h>
+#include <asm/io.h>
+#include <asm/nios2-io.h>
+
+static int altera_serial_setbaudrate(struct console_device *cdev, int baudrate)
+{
+	volatile struct nios_uart * uart = (struct nios_uart *)cdev->dev->map_base;
+	unsigned div;
+
+	div = (CPU_FREQ / baudrate) - 1;
+	writel(div, &uart->divisor);
+
+	return 0;
+}
+
+static void altera_serial_putc(struct console_device *cdev, char c)
+{
+	volatile struct nios_uart *uart = (struct nios_uart *)cdev->dev->map_base;
+
+	if (c == '\n')
+		altera_serial_putc(cdev, '\r');
+
+	while ((readl(&uart->status) & NIOS_UART_TRDY) == 0);
+	writel(c, &uart->txdata);
+}
+
+static int altera_serial_tstc(struct console_device *cdev)
+{
+	volatile struct nios_uart *uart = (struct nios_uart *)cdev->dev->map_base;
+
+	return readl(&uart->status) & NIOS_UART_RRDY;
+}
+
+static int altera_serial_getc(struct console_device *cdev)
+{
+	volatile struct nios_uart *uart = (struct nios_uart *)cdev->dev->map_base;
+
+	while (altera_serial_tstc(cdev) == 0);
+	return readl(&uart->rxdata) & 0x000000FF;
+}
+
+static int altera_serial_probe(struct device_d *dev)
+{
+	struct console_device *cdev;
+
+	cdev = malloc(sizeof(struct console_device));
+	dev->type_data = cdev;
+	cdev->dev = dev;
+	cdev->f_caps = CONSOLE_STDIN | CONSOLE_STDOUT | CONSOLE_STDERR;
+	cdev->tstc = altera_serial_tstc;
+	cdev->putc = altera_serial_putc;
+	cdev->getc = altera_serial_getc;
+	cdev->setbrg = altera_serial_setbaudrate;
+
+	console_register(cdev);
+
+	return 0;
+}
+
+static struct driver_d altera_serial_driver = {
+	.name  = "altera_serial",
+	.probe = altera_serial_probe,
+};
+
+static int altera_serial_init(void)
+{
+	register_driver(&altera_serial_driver);
+	return 0;
+}
+
+console_initcall(altera_serial_init);
+
-- 
1.7.0.4