Add common serial driver for Atmel AT32 and AT91 chips

Patch by Haavard Skinnemoen, 06 Sep 2006

This is a first attempt at creating a common serial driver for Atmel
chips. For now, it supports the AT32AP7000 AVR32 chip, but it should
be possible to support AT91RM9200 and other ARM-based chips with some
minor modifications.

There's nothing fundamentally AVR32-specific in this driver, but it
does use some features which are currently only defined for the
AT32AP CPU port:
  * pm_get_clock_freq: Obtain the clock frequency of a given domain
  * gd->console_uart: A "struct device" containing information about
    register mappings, gpio resources and clocks associated with the
    UART device.

For more information about these features, please see the "AT32AP
CPU" patch.

3 files changed, 403 insertions, 1 deletions

diff --git a/drivers/Makefile b/drivers/Makefile
index 5a7ab71..7628f56 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -27,7 +27,7 @@ include $(TOPDIR)/config.mk
 
 LIB	= $(obj)libdrivers.a
 
-COBJS	= 3c589.o 5701rls.o ali512x.o \
+COBJS	= 3c589.o 5701rls.o ali512x.o atmel_usart.o \
 	  bcm570x.o bcm570x_autoneg.o cfb_console.o cfi_flash.o \
 	  cs8900.o ct69000.o dataflash.o dc2114x.o dm9000x.o \
 	  e1000.o eepro100.o \
diff --git a/drivers/atmel_usart.c b/drivers/atmel_usart.c
new file mode 100644
index 0000000..41c3768
--- /dev/null
+++ b/drivers/atmel_usart.c
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * 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>
+
+#ifdef CONFIG_ATMEL_USART
+#include <asm/io.h>
+#include <asm/arch/platform.h>
+
+#include "atmel_usart.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+void serial_setbrg(void)
+{
+	unsigned long divisor;
+	unsigned long usart_hz;
+
+	/*
+	 *              Master Clock
+	 * Baud Rate = --------------
+	 *                16 * CD
+	 */
+	usart_hz = pm_get_clock_freq(gd->console_uart->resource[0].u.clock.id);
+	divisor = (usart_hz / 16 + gd->baudrate / 2) / gd->baudrate;
+	usart3_writel(gd->console_uart, BRGR, USART3_BF(CD, divisor));
+}
+
+int serial_init(void)
+{
+	usart3_writel(gd->console_uart, CR,
+		      USART3_BIT(RSTRX) | USART3_BIT(RSTTX));
+
+	serial_setbrg();
+
+	usart3_writel(gd->console_uart, CR,
+		      USART3_BIT(RXEN) | USART3_BIT(TXEN));
+	usart3_writel(gd->console_uart, MR,
+		      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));
+
+	return 0;
+}
+
+void serial_putc(char c)
+{
+	if (c == '\n')
+		serial_putc('\r');
+
+	while (!(usart3_readl(gd->console_uart, CSR) & USART3_BIT(TXRDY))) ;
+	usart3_writel(gd->console_uart, THR, c);
+}
+
+void serial_puts(const char *s)
+{
+	while (*s)
+		serial_putc(*s++);
+}
+
+int serial_getc(void)
+{
+	while (!(usart3_readl(gd->console_uart, CSR) & USART3_BIT(RXRDY))) ;
+	return usart3_readl(gd->console_uart, RHR);
+}
+
+int serial_tstc(void)
+{
+	return (usart3_readl(gd->console_uart, CSR) & USART3_BIT(RXRDY)) != 0;
+}
+
+#endif /* CONFIG_ATMEL_USART */
diff --git a/drivers/atmel_usart.h b/drivers/atmel_usart.h
new file mode 100644
index 0000000..fad90a8
--- /dev/null
+++ b/drivers/atmel_usart.h
@@ -0,0 +1,314 @@
+/*
+ * Register definitions for the Atmel USART3 module.
+ *
+ * Copyright (C) 2005-2006 Atmel Corporation
+ *
+ * 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
+ */
+#ifndef __DRIVERS_ATMEL_USART_H__
+#define __DRIVERS_ATMEL_USART_H__
+
+/* USART3 register offsets */
+#define USART3_CR				0x0000
+#define USART3_MR				0x0004
+#define USART3_IER				0x0008
+#define USART3_IDR				0x000c
+#define USART3_IMR				0x0010
+#define USART3_CSR				0x0014
+#define USART3_RHR				0x0018
+#define USART3_THR				0x001c
+#define USART3_BRGR				0x0020
+#define USART3_RTOR				0x0024
+#define USART3_TTGR				0x0028
+#define USART3_FIDI				0x0040
+#define USART3_NER				0x0044
+#define USART3_XXR				0x0048
+#define USART3_IFR				0x004c
+#define USART3_RPR				0x0100
+#define USART3_RCR				0x0104
+#define USART3_TPR				0x0108
+#define USART3_TCR				0x010c
+#define USART3_RNPR				0x0110
+#define USART3_RNCR				0x0114
+#define USART3_TNPR				0x0118
+#define USART3_TNCR				0x011c
+#define USART3_PTCR				0x0120
+#define USART3_PTSR				0x0124
+
+/* Bitfields in CR */
+#define USART3_RSTRX_OFFSET			2
+#define USART3_RSTRX_SIZE			1
+#define USART3_RSTTX_OFFSET			3
+#define USART3_RSTTX_SIZE			1
+#define USART3_RXEN_OFFSET			4
+#define USART3_RXEN_SIZE			1
+#define USART3_RXDIS_OFFSET			5
+#define USART3_RXDIS_SIZE			1
+#define USART3_TXEN_OFFSET			6
+#define USART3_TXEN_SIZE			1
+#define USART3_TXDIS_OFFSET			7
+#define USART3_TXDIS_SIZE			1
+#define USART3_RSTSTA_OFFSET			8
+#define USART3_RSTSTA_SIZE			1
+#define USART3_STTBRK_OFFSET			9
+#define USART3_STTBRK_SIZE			1
+#define USART3_STPBRK_OFFSET			10
+#define USART3_STPBRK_SIZE			1
+#define USART3_STTTO_OFFSET			11
+#define USART3_STTTO_SIZE			1
+#define USART3_SENDA_OFFSET			12
+#define USART3_SENDA_SIZE			1
+#define USART3_RSTIT_OFFSET			13
+#define USART3_RSTIT_SIZE			1
+#define USART3_RSTNACK_OFFSET			14
+#define USART3_RSTNACK_SIZE			1
+#define USART3_RETTO_OFFSET			15
+#define USART3_RETTO_SIZE			1
+#define USART3_DTREN_OFFSET			16
+#define USART3_DTREN_SIZE			1
+#define USART3_DTRDIS_OFFSET			17
+#define USART3_DTRDIS_SIZE			1
+#define USART3_RTSEN_OFFSET			18
+#define USART3_RTSEN_SIZE			1
+#define USART3_RTSDIS_OFFSET			19
+#define USART3_RTSDIS_SIZE			1
+#define USART3_COMM_TX_OFFSET			30
+#define USART3_COMM_TX_SIZE			1
+#define USART3_COMM_RX_OFFSET			31
+#define USART3_COMM_RX_SIZE			1
+
+/* Bitfields in MR */
+#define USART3_USART_MODE_OFFSET		0
+#define USART3_USART_MODE_SIZE			4
+#define USART3_USCLKS_OFFSET			4
+#define USART3_USCLKS_SIZE			2
+#define USART3_CHRL_OFFSET			6
+#define USART3_CHRL_SIZE			2
+#define USART3_SYNC_OFFSET			8
+#define USART3_SYNC_SIZE			1
+#define USART3_PAR_OFFSET			9
+#define USART3_PAR_SIZE				3
+#define USART3_NBSTOP_OFFSET			12
+#define USART3_NBSTOP_SIZE			2
+#define USART3_CHMODE_OFFSET			14
+#define USART3_CHMODE_SIZE			2
+#define USART3_MSBF_OFFSET			16
+#define USART3_MSBF_SIZE			1
+#define USART3_MODE9_OFFSET			17
+#define USART3_MODE9_SIZE			1
+#define USART3_CLKO_OFFSET			18
+#define USART3_CLKO_SIZE			1
+#define USART3_OVER_OFFSET			19
+#define USART3_OVER_SIZE			1
+#define USART3_INACK_OFFSET			20
+#define USART3_INACK_SIZE			1
+#define USART3_DSNACK_OFFSET			21
+#define USART3_DSNACK_SIZE			1
+#define USART3_MAX_ITERATION_OFFSET		24
+#define USART3_MAX_ITERATION_SIZE		3
+#define USART3_FILTER_OFFSET			28
+#define USART3_FILTER_SIZE			1
+
+/* Bitfields in CSR */
+#define USART3_RXRDY_OFFSET			0
+#define USART3_RXRDY_SIZE			1
+#define USART3_TXRDY_OFFSET			1
+#define USART3_TXRDY_SIZE			1
+#define USART3_RXBRK_OFFSET			2
+#define USART3_RXBRK_SIZE			1
+#define USART3_ENDRX_OFFSET			3
+#define USART3_ENDRX_SIZE			1
+#define USART3_ENDTX_OFFSET			4
+#define USART3_ENDTX_SIZE			1
+#define USART3_OVRE_OFFSET			5
+#define USART3_OVRE_SIZE			1
+#define USART3_FRAME_OFFSET			6
+#define USART3_FRAME_SIZE			1
+#define USART3_PARE_OFFSET			7
+#define USART3_PARE_SIZE			1
+#define USART3_TIMEOUT_OFFSET			8
+#define USART3_TIMEOUT_SIZE			1
+#define USART3_TXEMPTY_OFFSET			9
+#define USART3_TXEMPTY_SIZE			1
+#define USART3_ITERATION_OFFSET			10
+#define USART3_ITERATION_SIZE			1
+#define USART3_TXBUFE_OFFSET			11
+#define USART3_TXBUFE_SIZE			1
+#define USART3_RXBUFF_OFFSET			12
+#define USART3_RXBUFF_SIZE			1
+#define USART3_NACK_OFFSET			13
+#define USART3_NACK_SIZE			1
+#define USART3_RIIC_OFFSET			16
+#define USART3_RIIC_SIZE			1
+#define USART3_DSRIC_OFFSET			17
+#define USART3_DSRIC_SIZE			1
+#define USART3_DCDIC_OFFSET			18
+#define USART3_DCDIC_SIZE			1
+#define USART3_CTSIC_OFFSET			19
+#define USART3_CTSIC_SIZE			1
+#define USART3_RI_OFFSET			20
+#define USART3_RI_SIZE				1
+#define USART3_DSR_OFFSET			21
+#define USART3_DSR_SIZE				1
+#define USART3_DCD_OFFSET			22
+#define USART3_DCD_SIZE				1
+#define USART3_CTS_OFFSET			23
+#define USART3_CTS_SIZE				1
+
+/* Bitfields in RHR */
+#define USART3_RXCHR_OFFSET			0
+#define USART3_RXCHR_SIZE			9
+
+/* Bitfields in THR */
+#define USART3_TXCHR_OFFSET			0
+#define USART3_TXCHR_SIZE			9
+
+/* Bitfields in BRGR */
+#define USART3_CD_OFFSET			0
+#define USART3_CD_SIZE				16
+
+/* Bitfields in RTOR */
+#define USART3_TO_OFFSET			0
+#define USART3_TO_SIZE				16
+
+/* Bitfields in TTGR */
+#define USART3_TG_OFFSET			0
+#define USART3_TG_SIZE				8
+
+/* Bitfields in FIDI */
+#define USART3_FI_DI_RATIO_OFFSET		0
+#define USART3_FI_DI_RATIO_SIZE			11
+
+/* Bitfields in NER */
+#define USART3_NB_ERRORS_OFFSET			0
+#define USART3_NB_ERRORS_SIZE			8
+
+/* Bitfields in XXR */
+#define USART3_XOFF_OFFSET			0
+#define USART3_XOFF_SIZE			8
+#define USART3_XON_OFFSET			8
+#define USART3_XON_SIZE				8
+
+/* Bitfields in IFR */
+#define USART3_IRDA_FILTER_OFFSET		0
+#define USART3_IRDA_FILTER_SIZE			8
+
+/* Bitfields in RCR */
+#define USART3_RXCTR_OFFSET			0
+#define USART3_RXCTR_SIZE			16
+
+/* Bitfields in TCR */
+#define USART3_TXCTR_OFFSET			0
+#define USART3_TXCTR_SIZE			16
+
+/* Bitfields in RNCR */
+#define USART3_RXNCR_OFFSET			0
+#define USART3_RXNCR_SIZE			16
+
+/* Bitfields in TNCR */
+#define USART3_TXNCR_OFFSET			0
+#define USART3_TXNCR_SIZE			16
+
+/* Bitfields in PTCR */
+#define USART3_RXTEN_OFFSET			0
+#define USART3_RXTEN_SIZE			1
+#define USART3_RXTDIS_OFFSET			1
+#define USART3_RXTDIS_SIZE			1
+#define USART3_TXTEN_OFFSET			8
+#define USART3_TXTEN_SIZE			1
+#define USART3_TXTDIS_OFFSET			9
+#define USART3_TXTDIS_SIZE			1
+
+/* Constants for USART_MODE */
+#define USART3_USART_MODE_NORMAL		0
+#define USART3_USART_MODE_RS485			1
+#define USART3_USART_MODE_HARDWARE		2
+#define USART3_USART_MODE_MODEM			3
+#define USART3_USART_MODE_ISO7816_T0		4
+#define USART3_USART_MODE_ISO7816_T1		6
+#define USART3_USART_MODE_IRDA			8
+
+/* Constants for USCLKS */
+#define USART3_USCLKS_MCK			0
+#define USART3_USCLKS_MCK_DIV			1
+#define USART3_USCLKS_SCK			3
+
+/* Constants for CHRL */
+#define USART3_CHRL_5				0
+#define USART3_CHRL_6				1
+#define USART3_CHRL_7				2
+#define USART3_CHRL_8				3
+
+/* Constants for PAR */
+#define USART3_PAR_EVEN				0
+#define USART3_PAR_ODD				1
+#define USART3_PAR_SPACE			2
+#define USART3_PAR_MARK				3
+#define USART3_PAR_NONE				4
+#define USART3_PAR_MULTI			6
+
+/* Constants for NBSTOP */
+#define USART3_NBSTOP_1				0
+#define USART3_NBSTOP_1_5			1
+#define USART3_NBSTOP_2				2
+
+/* Constants for CHMODE */
+#define USART3_CHMODE_NORMAL			0
+#define USART3_CHMODE_ECHO			1
+#define USART3_CHMODE_LOCAL_LOOP		2
+#define USART3_CHMODE_REMOTE_LOOP		3
+
+/* Constants for MSBF */
+#define USART3_MSBF_LSBF			0
+#define USART3_MSBF_MSBF			1
+
+/* Constants for OVER */
+#define USART3_OVER_X16				0
+#define USART3_OVER_X8				1
+
+/* Constants for CD */
+#define USART3_CD_DISABLE			0
+#define USART3_CD_BYPASS			1
+
+/* Constants for TO */
+#define USART3_TO_DISABLE			0
+
+/* Constants for TG */
+#define USART3_TG_DISABLE			0
+
+/* Constants for FI_DI_RATIO */
+#define USART3_FI_DI_RATIO_DISABLE		0
+
+/* Bit manipulation macros */
+#define USART3_BIT(name)				\
+	(1 << USART3_##name##_OFFSET)
+#define USART3_BF(name,value)				\
+	(((value) & ((1 << USART3_##name##_SIZE) - 1))	\
+	 << USART3_##name##_OFFSET)
+#define USART3_BFEXT(name,value)			\
+	(((value) >> USART3_##name##_OFFSET)		\
+	 & ((1 << USART3_##name##_SIZE) - 1))
+#define USART3_BFINS(name,value,old)			\
+	(((old) & ~(((1 << USART3_##name##_SIZE) - 1)	\
+		    << USART3_##name##_OFFSET))		\
+	 | USART3_BF(name,value))
+
+/* Register access macros */
+#define usart3_readl(port,reg)				\
+	readl((port)->regs + USART3_##reg)
+#define usart3_writel(port,reg,value)			\
+	writel((value), (port)->regs + USART3_##reg)
+
+#endif /* __DRIVERS_ATMEL_USART_H__ */