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Diffstat (limited to 'u-boot/drivers/serial/atmel_usart.c')
-rw-r--r--u-boot/drivers/serial/atmel_usart.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/u-boot/drivers/serial/atmel_usart.c b/u-boot/drivers/serial/atmel_usart.c
new file mode 100644
index 0000000..bfa1f3a
--- /dev/null
+++ b/u-boot/drivers/serial/atmel_usart.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * Modified to support C structur SoC access by
+ * Andreas Bießmann <biessmann@corscience.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 <watchdog.h>
+
+#include <asm/io.h>
+#include <asm/arch/clk.h>
+#include <asm/arch/memory-map.h>
+
+#if defined(CONFIG_USART0)
+# define USART_ID 0
+# define USART_BASE USART0_BASE
+#elif defined(CONFIG_USART1)
+# define USART_ID 1
+# define USART_BASE USART1_BASE
+#elif defined(CONFIG_USART2)
+# define USART_ID 2
+# define USART_BASE USART2_BASE
+#elif defined(CONFIG_USART3)
+# define USART_ID 3
+# define USART_BASE USART3_BASE
+#endif
+
+#include "atmel_usart.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+void serial_setbrg(void)
+{
+ atmel_usart3_t *usart = (atmel_usart3_t*)USART_BASE;
+ unsigned long divisor;
+ unsigned long usart_hz;
+
+ /*
+ * Master Clock
+ * Baud Rate = --------------
+ * 16 * CD
+ */
+ usart_hz = get_usart_clk_rate(USART_ID);
+ divisor = (usart_hz / 16 + gd->baudrate / 2) / gd->baudrate;
+ writel(USART3_BF(CD, divisor), &usart->brgr);
+}
+
+int serial_init(void)
+{
+ atmel_usart3_t *usart = (atmel_usart3_t*)USART_BASE;
+
+ writel(USART3_BIT(RSTRX) | USART3_BIT(RSTTX), &usart->cr);
+
+ serial_setbrg();
+
+ writel(USART3_BIT(RXEN) | USART3_BIT(TXEN), &usart->cr);
+ writel((USART3_BF(USART_MODE, USART3_USART_MODE_NORMAL)
+ | USART3_BF(USCLKS, USART3_USCLKS_MCK)
+ | USART3_BF(CHRL, USART3_CHRL_8)
+ | USART3_BF(PAR, USART3_PAR_NONE)
+ | USART3_BF(NBSTOP, USART3_NBSTOP_1)),
+ &usart->mr);
+
+ return 0;
+}
+
+void serial_putc(char c)
+{
+ atmel_usart3_t *usart = (atmel_usart3_t*)USART_BASE;
+
+ if (c == '\n')
+ serial_putc('\r');
+
+ while (!(readl(&usart->csr) & USART3_BIT(TXRDY)));
+ writel(c, &usart->thr);
+}
+
+void serial_puts(const char *s)
+{
+ while (*s)
+ serial_putc(*s++);
+}
+
+int serial_getc(void)
+{
+ atmel_usart3_t *usart = (atmel_usart3_t*)USART_BASE;
+
+ while (!(readl(&usart->csr) & USART3_BIT(RXRDY)))
+ WATCHDOG_RESET();
+ return readl(&usart->rhr);
+}
+
+int serial_tstc(void)
+{
+ atmel_usart3_t *usart = (atmel_usart3_t*)USART_BASE;
+ return (readl(&usart->csr) & USART3_BIT(RXRDY)) != 0;
+}