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path: root/drivers/serial/serial_imx.c
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Diffstat (limited to 'drivers/serial/serial_imx.c')
-rw-r--r--drivers/serial/serial_imx.c221
1 files changed, 221 insertions, 0 deletions
diff --git a/drivers/serial/serial_imx.c b/drivers/serial/serial_imx.c
new file mode 100644
index 0000000..b9ca748
--- /dev/null
+++ b/drivers/serial/serial_imx.c
@@ -0,0 +1,221 @@
+/*
+ * (c) 2004 Sascha Hauer <sascha@saschahauer.de>
+ *
+ * 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 <asm/arch/imx-regs.h>
+
+#if defined CONFIG_IMX_SERIAL1
+#define UART_BASE IMX_UART1_BASE
+#elif defined CONFIG_IMX_SERIAL2
+#define UART_BASE IMX_UART2_BASE
+#else
+#error "define CONFIG_IMX_SERIAL1, CONFIG_IMX_SERIAL2 or CONFIG_IMX_SERIAL_NONE"
+#endif
+
+struct imx_serial {
+ volatile uint32_t urxd[16];
+ volatile uint32_t utxd[16];
+ volatile uint32_t ucr1;
+ volatile uint32_t ucr2;
+ volatile uint32_t ucr3;
+ volatile uint32_t ucr4;
+ volatile uint32_t ufcr;
+ volatile uint32_t usr1;
+ volatile uint32_t usr2;
+ volatile uint32_t uesc;
+ volatile uint32_t utim;
+ volatile uint32_t ubir;
+ volatile uint32_t ubmr;
+ volatile uint32_t ubrc;
+ volatile uint32_t bipr[4];
+ volatile uint32_t bmpr[4];
+ volatile uint32_t uts;
+};
+
+DECLARE_GLOBAL_DATA_PTR;
+
+void serial_setbrg (void)
+{
+ serial_init();
+}
+
+extern void imx_gpio_mode(int gpio_mode);
+
+/*
+ * Initialise the serial port with the given baudrate. The settings
+ * are always 8 data bits, no parity, 1 stop bit, no start bits.
+ *
+ */
+int serial_init (void)
+{
+ volatile struct imx_serial* base = (struct imx_serial *)UART_BASE;
+ unsigned int ufcr_rfdiv;
+ unsigned int refclk;
+
+#ifdef CONFIG_IMX_SERIAL1
+ imx_gpio_mode(PC11_PF_UART1_TXD);
+ imx_gpio_mode(PC12_PF_UART1_RXD);
+#else
+ imx_gpio_mode(PB30_PF_UART2_TXD);
+ imx_gpio_mode(PB31_PF_UART2_RXD);
+#endif
+
+ /* Disable UART */
+ base->ucr1 &= ~UCR1_UARTEN;
+
+ /* Set to default POR state */
+
+ base->ucr1 = 0x00000004;
+ base->ucr2 = 0x00000000;
+ base->ucr3 = 0x00000000;
+ base->ucr4 = 0x00008040;
+ base->uesc = 0x0000002B;
+ base->utim = 0x00000000;
+ base->ubir = 0x00000000;
+ base->ubmr = 0x00000000;
+ base->uts = 0x00000000;
+ /* Set clocks */
+ base->ucr4 |= UCR4_REF16;
+
+ /* Configure FIFOs */
+ base->ufcr = 0xa81;
+
+ /* set the baud rate.
+ *
+ * baud * 16 x
+ * --------- = -
+ * refclk y
+ *
+ * x - 1 = UBIR
+ * y - 1 = UBMR
+ *
+ * each register is 16 bits wide. refclk max is 96 MHz
+ *
+ */
+
+ ufcr_rfdiv = ((base->ufcr) & UFCR_RFDIV) >> 7;
+ if (ufcr_rfdiv == 6)
+ ufcr_rfdiv = 7;
+ else
+ ufcr_rfdiv = 6 - ufcr_rfdiv;
+
+ refclk = get_PERCLK1();
+ refclk /= ufcr_rfdiv;
+
+ /* Set the numerator value minus one of the BRM ratio */
+ base->ubir = (gd->baudrate / 100) - 1;
+
+ /* Set the denominator value minus one of the BRM ratio */
+ base->ubmr = (refclk/(16 * 100)) - 1;
+
+ /* Set to 8N1 */
+ base->ucr2 &= ~UCR2_PREN;
+ base->ucr2 |= UCR2_WS;
+ base->ucr2 &= ~UCR2_STPB;
+
+ /* Ignore RTS */
+ base->ucr2 |= UCR2_IRTS;
+
+ /* Enable UART */
+ base->ucr1 |= UCR1_UARTEN | UCR1_UARTCLKEN;
+
+ /* Enable FIFOs */
+ base->ucr2 |= UCR2_SRST | UCR2_RXEN | UCR2_TXEN;
+
+ /* Clear status flags */
+ base->usr2 |= USR2_ADET |
+ USR2_DTRF |
+ USR2_IDLE |
+ USR2_IRINT |
+ USR2_WAKE |
+ USR2_RTSF |
+ USR2_BRCD |
+ USR2_ORE;
+
+ /* Clear status flags */
+ base->usr1 |= USR1_PARITYERR |
+ USR1_RTSD |
+ USR1_ESCF |
+ USR1_FRAMERR |
+ USR1_AIRINT |
+ USR1_AWAKE;
+ return (0);
+}
+
+/*
+ * Read a single byte from the serial port. Returns 1 on success, 0
+ * otherwise. When the function is successful, the character read is
+ * written into its argument c.
+ */
+int serial_getc (void)
+{
+ volatile struct imx_serial* base = (struct imx_serial *)UART_BASE;
+ unsigned char ch;
+
+ while(base->uts & UTS_RXEMPTY);
+
+ ch = (char)base->urxd[0];
+
+ return ch;
+}
+
+#ifdef CONFIG_HWFLOW
+static int hwflow = 0; /* turned off by default */
+int hwflow_onoff(int on)
+{
+}
+#endif
+
+/*
+ * Output a single byte to the serial port.
+ */
+void serial_putc (const char c)
+{
+ volatile struct imx_serial* base = (struct imx_serial *)UART_BASE;
+
+ /* Wait for Tx FIFO not full */
+ while (base->uts & UTS_TXFULL);
+
+ base->utxd[0] = c;
+
+ /* If \n, also do \r */
+ if (c == '\n')
+ serial_putc ('\r');
+}
+
+/*
+ * Test whether a character is in the RX buffer
+ */
+int serial_tstc (void)
+{
+ volatile struct imx_serial* base = (struct imx_serial *)UART_BASE;
+
+ /* If receive fifo is empty, return false */
+ if (base->uts & UTS_RXEMPTY)
+ return 0;
+ return 1;
+}
+
+void
+serial_puts (const char *s)
+{
+ while (*s) {
+ serial_putc (*s++);
+ }
+}