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Diffstat (limited to 'arch/mips/cpu/xburst/jz_serial.c')
-rw-r--r--arch/mips/cpu/xburst/jz_serial.c114
1 files changed, 114 insertions, 0 deletions
diff --git a/arch/mips/cpu/xburst/jz_serial.c b/arch/mips/cpu/xburst/jz_serial.c
new file mode 100644
index 0000000000..e6c48e0890
--- /dev/null
+++ b/arch/mips/cpu/xburst/jz_serial.c
@@ -0,0 +1,114 @@
+/*
+ * Jz4740 UART support
+ * Copyright (c) 2011
+ * Qi Hardware, Xiangfu Liu <xiangfu@sharism.cc>
+ *
+ * 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>
+#include <asm/jz4740.h>
+
+/*
+ * serial_init - initialize a channel
+ *
+ * This routine initializes the number of data bits, parity
+ * and set the selected baud rate. Interrupts are disabled.
+ * Set the modem control signals if the option is selected.
+ *
+ * RETURNS: N/A
+ */
+struct jz4740_uart *uart = (struct jz4740_uart *)CONFIG_SYS_UART_BASE;
+
+int serial_init(void)
+{
+ /* Disable port interrupts while changing hardware */
+ writeb(0, &uart->dlhr_ier);
+
+ /* Disable UART unit function */
+ writeb(~UART_FCR_UUE, &uart->iir_fcr);
+
+ /* Set both receiver and transmitter in UART mode (not SIR) */
+ writeb(~(SIRCR_RSIRE | SIRCR_TSIRE), &uart->isr);
+
+ /*
+ * Set databits, stopbits and parity.
+ * (8-bit data, 1 stopbit, no parity)
+ */
+ writeb(UART_LCR_WLEN_8 | UART_LCR_STOP_1, &uart->lcr);
+
+ /* Set baud rate */
+ serial_setbrg();
+
+ /* Enable UART unit, enable and clear FIFO */
+ writeb(UART_FCR_UUE | UART_FCR_FE | UART_FCR_TFLS | UART_FCR_RFLS,
+ &uart->iir_fcr);
+
+ return 0;
+}
+
+void serial_setbrg(void)
+{
+ u32 baud_div, tmp;
+
+ baud_div = CONFIG_SYS_EXTAL / 16 / CONFIG_BAUDRATE;
+
+ tmp = readb(&uart->lcr);
+ tmp |= UART_LCR_DLAB;
+ writeb(tmp, &uart->lcr);
+
+ writeb((baud_div >> 8) & 0xff, &uart->dlhr_ier);
+ writeb(baud_div & 0xff, &uart->rbr_thr_dllr);
+
+ tmp &= ~UART_LCR_DLAB;
+ writeb(tmp, &uart->lcr);
+}
+
+int serial_tstc(void)
+{
+ if (readb(&uart->lsr) & UART_LSR_DR)
+ return 1;
+
+ return 0;
+}
+
+void serial_putc(const char c)
+{
+ if (c == '\n')
+ serial_putc('\r');
+
+ /* Wait for fifo to shift out some bytes */
+ while (!((readb(&uart->lsr) & (UART_LSR_TDRQ | UART_LSR_TEMT)) == 0x60))
+ ;
+
+ writeb((u8)c, &uart->rbr_thr_dllr);
+}
+
+int serial_getc(void)
+{
+ while (!serial_tstc())
+ ;
+
+ return readb(&uart->rbr_thr_dllr);
+}
+
+void serial_puts(const char *s)
+{
+ while (*s)
+ serial_putc(*s++);
+}