serial: Add Tegra2 serial port support

Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/drivers/serial/serial_tegra2.c b/drivers/serial/serial_tegra2.c
new file mode 100644
index 0000000..8ff34ea
--- /dev/null
+++ b/drivers/serial/serial_tegra2.c
@@ -0,0 +1,77 @@
+/*
+ *  (C) Copyright 2010,2011
+ *  NVIDIA Corporation <www.nvidia.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 <ns16550.h>
+#include <asm/io.h>
+#include <asm/arch/tegra2.h>
+#include "serial_tegra2.h"
+
+static void setup_uart(struct uart_ctlr *u)
+{
+	u32 reg;
+
+	/* Prepare the divisor value */
+	reg = NVRM_PLLP_FIXED_FREQ_KHZ * 1000 / NV_DEFAULT_DEBUG_BAUD / 16;
+
+	/* Set up UART parameters */
+	writel(UART_LCR_DLAB, &u->uart_lcr);
+	writel(reg, &u->uart_thr_dlab_0);
+	writel(0, &u->uart_ier_dlab_0);
+	writel(0, &u->uart_lcr);			/* clear DLAB */
+	writel((UART_FCR_TRIGGER_3 | UART_FCR_FIFO_EN | \
+		UART_FCR_CLEAR_XMIT | UART_FCR_CLEAR_RCVR), &u->uart_iir_fcr);
+	writel(0, &u->uart_ier_dlab_0);
+	writel(UART_LCR_WLS_8, &u->uart_lcr);	/* 8N1 */
+	writel(UART_MCR_RTS, &u->uart_mcr);
+	writel(0, &u->uart_msr);
+	writel(0, &u->uart_spr);
+	writel(0, &u->uart_irda_csr);
+	writel(0, &u->uart_asr);
+	writel((UART_FCR_TRIGGER_3 | UART_FCR_FIFO_EN), &u->uart_iir_fcr);
+
+	/* Flush any old characters out of the RX FIFO */
+	reg = readl(&u->uart_lsr);
+
+	while (reg & UART_LSR_DR) {
+		reg = readl(&u->uart_thr_dlab_0);
+		reg = readl(&u->uart_lsr);
+	}
+}
+
+/*
+ * Routine: uart_init
+ * Description: init the UART clocks, muxes, and baudrate/parity/etc.
+ */
+void uart_init(void)
+{
+	struct uart_ctlr *uart = (struct uart_ctlr *)NV_PA_APB_UARTD_BASE;
+#if defined(CONFIG_TEGRA2_ENABLE_UARTD)
+	setup_uart(uart);
+#endif	/* CONFIG_TEGRA2_ENABLE_UARTD */
+#if defined(CONFIG_TEGRA2_ENABLE_UARTA)
+	uart = (struct uart_ctlr *)NV_PA_APB_UARTA_BASE;
+
+	setup_uart(uart);
+#endif	/* CONFIG_TEGRA2_ENABLE_UARTA */
+}