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/*
 * (c) 2007 Sascha Hauer <s.hauer@pengutronix.de>
 *
 * (C) Copyright 2008-2009 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>

#if defined CONFIG_MX35_UART

#include <asm/arch/mx35.h>

#define __REG(x)     (*((volatile u32 *)(x)))

#define UART_PHYS CONFIG_MX35_UART

/* Register definitions */
#define URXD  0x0		/* Receiver Register */
#define UTXD  0x40		/* Transmitter Register */
#define UCR1  0x80		/* Control Register 1 */
#define UCR2  0x84		/* Control Register 2 */
#define UCR3  0x88		/* Control Register 3 */
#define UCR4  0x8c		/* Control Register 4 */
#define UFCR  0x90		/* FIFO Control Register */
#define USR1  0x94		/* Status Register 1 */
#define USR2  0x98		/* Status Register 2 */
#define UESC  0x9c		/* Escape Character Register */
#define UTIM  0xa0		/* Escape Timer Register */
#define UBIR  0xa4		/* BRM Incremental Register */
#define UBMR  0xa8		/* BRM Modulator Register */
#define UBRC  0xac		/* Baud Rate Count Register */
#define UTS   0xb4		/* UART Test Register (mx31) */

/* UART Control Register Bit Fields.*/
#define  URXD_CHARRDY    (1<<15)
#define  URXD_ERR        (1<<14)
#define  URXD_OVRRUN     (1<<13)
#define  URXD_FRMERR     (1<<12)
#define  URXD_BRK        (1<<11)
#define  URXD_PRERR      (1<<10)
#define  UCR1_ADEN       (1<<15)	/* Auto dectect interrupt */
#define  UCR1_ADBR       (1<<14)	/* Auto detect baud rate */
#define  UCR1_TRDYEN     (1<<13)	/* Transmitter ready interrupt enable */
#define  UCR1_IDEN       (1<<12)	/* Idle condition interrupt */
#define  UCR1_RRDYEN     (1<<9)	/* Recv ready interrupt enable */
#define  UCR1_RDMAEN     (1<<8)	/* Recv ready DMA enable */
#define  UCR1_IREN       (1<<7)	/* Infrared interface enable */
#define  UCR1_TXMPTYEN   (1<<6)	/* Transimitter empty interrupt enable */
#define  UCR1_RTSDEN     (1<<5)	/* RTS delta interrupt enable */
#define  UCR1_SNDBRK     (1<<4)	/* Send break */
#define  UCR1_TDMAEN     (1<<3)	/* Transmitter ready DMA enable */
#define  UCR1_UARTCLKEN  (1<<2)	/* UART clock enabled */
#define  UCR1_DOZE       (1<<1)	/* Doze */
#define  UCR1_UARTEN     (1<<0)	/* UART enabled */
#define  UCR2_ESCI     	 (1<<15)	/* Escape seq interrupt enable */
#define  UCR2_IRTS  	 (1<<14)	/* Ignore RTS pin */
#define  UCR2_CTSC  	 (1<<13)	/* CTS pin control */
#define  UCR2_CTS        (1<<12)	/* Clear to send */
#define  UCR2_ESCEN      (1<<11)	/* Escape enable */
#define  UCR2_PREN       (1<<8)	/* Parity enable */
#define  UCR2_PROE       (1<<7)	/* Parity odd/even */
#define  UCR2_STPB       (1<<6)	/* Stop */
#define  UCR2_WS         (1<<5)	/* Word size */
#define  UCR2_RTSEN      (1<<4)	/* Request to send interrupt enable */
#define  UCR2_TXEN       (1<<2)	/* Transmitter enabled */
#define  UCR2_RXEN       (1<<1)	/* Receiver enabled */
#define  UCR2_SRST 	 (1<<0)	/* SW reset */
#define  UCR3_DTREN 	 (1<<13)	/* DTR interrupt enable */
#define  UCR3_PARERREN   (1<<12)	/* Parity enable */
#define  UCR3_FRAERREN   (1<<11)	/* Frame error interrupt enable */
#define  UCR3_DSR        (1<<10)	/* Data set ready */
#define  UCR3_DCD        (1<<9)	/* Data carrier detect */
#define  UCR3_RI         (1<<8)	/* Ring indicator */
#define  UCR3_TIMEOUTEN  (1<<7)	/* Timeout interrupt enable */
#define  UCR3_RXDSEN	 (1<<6)	/* Receive status interrupt enable */
#define  UCR3_AIRINTEN   (1<<5)	/* Async IR wake interrupt enable */
#define  UCR3_AWAKEN	 (1<<4)	/* Async wake interrupt enable */
#define  UCR3_REF25 	 (1<<3)	/* Ref freq 25 MHz */
#define  UCR3_REF30 	 (1<<2)	/* Ref Freq 30 MHz */
#define  UCR3_INVT  	 (1<<1)	/* Inverted Infrared transmission */
#define  UCR3_BPEN  	 (1<<0)	/* Preset registers enable */
#define  UCR4_CTSTL_32   (32<<10)	/* CTS trigger level (32 chars) */
#define  UCR4_INVR  	 (1<<9)	/* Inverted infrared reception */
#define  UCR4_ENIRI 	 (1<<8)	/* Serial infrared interrupt enable */
#define  UCR4_WKEN  	 (1<<7)	/* Wake interrupt enable */
#define  UCR4_REF16 	 (1<<6)	/* Ref freq 16 MHz */
#define  UCR4_IRSC  	 (1<<5)	/* IR special case */
#define  UCR4_TCEN  	 (1<<3)	/* Transmit complete interrupt enable */
#define  UCR4_BKEN  	 (1<<2)	/* Break condition interrupt enable */
#define  UCR4_OREN  	 (1<<1)	/* Receiver overrun interrupt enable */
#define  UCR4_DREN  	 (1<<0)	/* Recv data ready interrupt enable */
#define  UFCR_RXTL_SHF   0	/* Receiver trigger level shift */
#define  UFCR_RFDIV      (7<<7)	/* Reference freq divider mask */
#define  UFCR_TXTL_SHF   10	/* Transmitter trigger level shift */
#define  USR1_PARITYERR  (1<<15)	/* Parity error interrupt flag */
#define  USR1_RTSS  	 (1<<14)	/* RTS pin status */
#define  USR1_TRDY  	 (1<<13)/* Transmitter ready interrupt/dma flag */
#define  USR1_RTSD  	 (1<<12)	/* RTS delta */
#define  USR1_ESCF  	 (1<<11)	/* Escape seq interrupt flag */
#define  USR1_FRAMERR    (1<<10)	/* Frame error interrupt flag */
#define  USR1_RRDY       (1<<9)	/* Receiver ready interrupt/dma flag */
#define  USR1_TIMEOUT    (1<<7)	/* Receive timeout interrupt status */
#define  USR1_RXDS  	 (1<<6)	/* Receiver idle interrupt flag */
#define  USR1_AIRINT	 (1<<5)	/* Async IR wake interrupt flag */
#define  USR1_AWAKE 	 (1<<4)	/* Aysnc wake interrupt flag */
#define  USR2_ADET  	 (1<<15)	/* Auto baud rate detect complete */
#define  USR2_TXFE  	 (1<<14)	/* Transmit buffer FIFO empty */
#define  USR2_DTRF  	 (1<<13)	/* DTR edge interrupt flag */
#define  USR2_IDLE  	 (1<<12)	/* Idle condition */
#define  USR2_IRINT 	 (1<<8)	/* Serial infrared interrupt flag */
#define  USR2_WAKE  	 (1<<7)	/* Wake */
#define  USR2_RTSF  	 (1<<4)	/* RTS edge interrupt flag */
#define  USR2_TXDC  	 (1<<3)	/* Transmitter complete */
#define  USR2_BRCD  	 (1<<2)	/* Break condition */
#define  USR2_ORE        (1<<1)	/* Overrun error */
#define  USR2_RDR        (1<<0)	/* Recv data ready */
#define  UTS_FRCPERR	 (1<<13)	/* Force parity error */
#define  UTS_LOOP        (1<<12)	/* Loop tx and rx */
#define  UTS_TXEMPTY	 (1<<6)	/* TxFIFO empty */
#define  UTS_RXEMPTY	 (1<<5)	/* RxFIFO empty */
#define  UTS_TXFULL 	 (1<<4)	/* TxFIFO full */
#define  UTS_RXFULL 	 (1<<3)	/* RxFIFO full */
#define  UTS_SOFTRST	 (1<<0)	/* Software reset */

DECLARE_GLOBAL_DATA_PTR;

void serial_setbrg(void)
{
	u32 clk = mxc_get_clock(MXC_UART_CLK);

	if (!gd->baudrate)
		gd->baudrate = CONFIG_BAUDRATE;
	__REG(UART_PHYS + UFCR) = 0x4 << 7;	/* divide input clock by 2 */
	__REG(UART_PHYS + UBIR) = 0xf;
	__REG(UART_PHYS + UBMR) = clk / (2 * gd->baudrate);
}

int serial_getc(void)
{
	while (__REG(UART_PHYS + UTS) & UTS_RXEMPTY)
		;
	return __REG(UART_PHYS + URXD);
}

void serial_putc(const char c)
{
	__REG(UART_PHYS + UTXD) = c;

	/* wait for transmitter to be ready */
	while (!(__REG(UART_PHYS + UTS) & UTS_TXEMPTY))
		;

	/* If \n, also do \r */
	if (c == '\n')
		serial_putc('\r');
}

/*
 * Test whether a character is in the RX buffer
 */
int serial_tstc(void)
{
	/* If receive fifo is empty, return false */
	if (__REG(UART_PHYS + UTS) & UTS_RXEMPTY)
		return 0;
	return 1;
}

void serial_puts(const char *s)
{
	while (*s)
		serial_putc(*s++);
}

/*
 * 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)
{
	__REG(UART_PHYS + UCR1) = 0x0;
	__REG(UART_PHYS + UCR2) = 0x0;

	while (!(__REG(UART_PHYS + UCR2) & UCR2_SRST))
		;

	__REG(UART_PHYS + UCR3) = 0x0704;
	__REG(UART_PHYS + UCR4) = 0x8000;
	__REG(UART_PHYS + UESC) = 0x002b;
	__REG(UART_PHYS + UTIM) = 0x0;

	__REG(UART_PHYS + UTS) = 0x0;

	serial_setbrg();

	__REG(UART_PHYS + UCR2) =
	    UCR2_WS | UCR2_IRTS | UCR2_RXEN | UCR2_TXEN | UCR2_SRST;

	__REG(UART_PHYS + UCR1) = UCR1_UARTEN;

	return 0;
}

#endif				/* CONFIG_MX35 */