arm: vf610: Add uart support for Vybrid VF610

This patch adds lpuart support for Vybrid VF610 platform.

Signed-off-by: TsiChung Liew <tsicliew@gmail.com>
Signed-off-by: Alison Wang <b18965@freescale.com>

diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index fbc4e97e983fd2bbd8085acdcf71e04fe34743f3..bb6559b27c7738d107b616ecdb93337729a66a4a 100644 (file)
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -52,6 +52,7 @@ COBJS-$(CONFIG_XILINX_UARTLITE) += serial_xuartlite.o
 COBJS-$(CONFIG_SANDBOX_SERIAL) += sandbox.o
 COBJS-$(CONFIG_SCIF_CONSOLE) += serial_sh.o
 COBJS-$(CONFIG_ZYNQ_SERIAL) += serial_zynq.o
+COBJS-$(CONFIG_FSL_LPUART) += serial_lpuart.o
 
 ifndef CONFIG_SPL_BUILD
 COBJS-$(CONFIG_USB_TTY) += usbtty.o

diff --git a/drivers/serial/serial_lpuart.c b/drivers/serial/serial_lpuart.c
new file mode 100644 (file)
index 0000000..51d5666
--- /dev/null
+++ b/drivers/serial/serial_lpuart.c
@@ -0,0 +1,132 @@
+/*
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ *
+ * 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 <watchdog.h>
+#include <asm/io.h>
+#include <serial.h>
+#include <linux/compiler.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/clock.h>
+
+#define US1_TDRE        (1 << 7)
+#define US1_RDRF        (1 << 5)
+#define UC2_TE          (1 << 3)
+#define UC2_RE          (1 << 2)
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct lpuart_fsl *base = (struct lpuart_fsl *)LPUART_BASE;
+
+static void lpuart_serial_setbrg(void)
+{
+       u32 clk = mxc_get_clock(MXC_UART_CLK);
+       u16 sbr;
+
+       if (!gd->baudrate)
+               gd->baudrate = CONFIG_BAUDRATE;
+
+       sbr = (u16)(clk / (16 * gd->baudrate));
+       /* place adjustment later - n/32 BRFA */
+
+       __raw_writeb(sbr >> 8, &base->ubdh);
+       __raw_writeb(sbr & 0xff, &base->ubdl);
+}
+
+static int lpuart_serial_getc(void)
+{
+       u8 status;
+
+       while (!(__raw_readb(&base->us1) & US1_RDRF))
+               WATCHDOG_RESET();
+
+       status = __raw_readb(&base->us1);
+       status |= US1_RDRF;
+       __raw_writeb(status, &base->us1);
+
+       return __raw_readb(&base->ud);
+}
+
+static void lpuart_serial_putc(const char c)
+{
+       if (c == '\n')
+               serial_putc('\r');
+
+       while (!(__raw_readb(&base->us1) & US1_TDRE))
+               WATCHDOG_RESET();
+
+       __raw_writeb(c, &base->ud);
+}
+
+/*
+ * Test whether a character is in the RX buffer
+ */
+static int lpuart_serial_tstc(void)
+{
+       if (__raw_readb(&base->urcfifo) == 0)
+               return 0;
+
+       return 1;
+}
+
+/*
+ * Initialise the serial port with the given baudrate. The settings
+ * are always 8 data bits, no parity, 1 stop bit, no start bits.
+ */
+static int lpuart_serial_init(void)
+{
+       u8 ctrl;
+
+       ctrl = __raw_readb(&base->uc2);
+       ctrl &= ~UC2_RE;
+       ctrl &= ~UC2_TE;
+       __raw_writeb(ctrl, &base->uc2);
+
+       __raw_writeb(0, &base->umodem);
+       __raw_writeb(0, &base->uc1);
+
+       /* provide data bits, parity, stop bit, etc */
+
+       serial_setbrg();
+
+       __raw_writeb(UC2_RE | UC2_TE, &base->uc2);
+
+       return 0;
+}
+
+static struct serial_device lpuart_serial_drv = {
+       .name = "lpuart_serial",
+       .start = lpuart_serial_init,
+       .stop = NULL,
+       .setbrg = lpuart_serial_setbrg,
+       .putc = lpuart_serial_putc,
+       .puts = default_serial_puts,
+       .getc = lpuart_serial_getc,
+       .tstc = lpuart_serial_tstc,
+};
+
+void lpuart_serial_initialize(void)
+{
+       serial_register(&lpuart_serial_drv);
+}
+
+__weak struct serial_device *default_serial_console(void)
+{
+       return &lpuart_serial_drv;
+}