u-boot/drivers/serial/serial_mxc.c
Stefano Babic 4ec3d2a745 MXC: Add watchdog support to serial driver
Calls WATCHDOG_RESET() inside serial driver
for boards enabling watchdog.

Signed-off-by: Stefano Babic <sbabic@denx.de>
2010-09-29 11:24:31 +02:00

256 lines
9.5 KiB
C

/*
* (c) 2007 Sascha Hauer <s.hauer@pengutronix.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>
#ifdef CONFIG_MX31
#include <asm/arch/mx31.h>
#else
#include <asm/arch/imx-regs.h>
#include <asm/arch/clock.h>
#endif
#define __REG(x) (*((volatile u32 *)(x)))
#if defined(CONFIG_SYS_MX31_UART1) || defined(CONFIG_SYS_MX25_UART1)
#define UART_PHYS 0x43f90000
#elif defined(CONFIG_SYS_MX31_UART2) || defined(CONFIG_SYS_MX25_UART2)
#define UART_PHYS 0x43f94000
#elif defined(CONFIG_SYS_MX31_UART3) || defined(CONFIG_SYS_MX25_UART3)
#define UART_PHYS 0x5000c000
#elif defined(CONFIG_SYS_MX31_UART4) || defined(CONFIG_SYS_MX25_UART4)
#define UART_PHYS 0x43fb0000
#elif defined(CONFIG_SYS_MX31_UART5) || defined(CONFIG_SYS_MX25_UART5)
#define UART_PHYS 0x43fb4000
#elif defined(CONFIG_SYS_MX27_UART1)
#define UART_PHYS 0x1000a000
#elif defined(CONFIG_SYS_MX27_UART2)
#define UART_PHYS 0x1000b000
#elif defined(CONFIG_SYS_MX27_UART3)
#define UART_PHYS 0x1000c000
#elif defined(CONFIG_SYS_MX27_UART4)
#define UART_PHYS 0x1000d000
#elif defined(CONFIG_SYS_MX27_UART5)
#define UART_PHYS 0x1001b000
#elif defined(CONFIG_SYS_MX27_UART6)
#define UART_PHYS 0x1001c000
#elif defined(CONFIG_SYS_MX51_UART1)
#define UART_PHYS UART1_BASE_ADDR
#elif defined(CONFIG_SYS_MX51_UART2)
#define UART_PHYS UART2_BASE_ADDR
#elif defined(CONFIG_SYS_MX51_UART3)
#define UART_PHYS UART3_BASE_ADDR
#else
#error "define CONFIG_SYS_MXxx_UARTx to use the MXC UART driver"
#endif
#ifdef CONFIG_SERIAL_MULTI
#warning "MXC driver does not support MULTI serials."
#endif
/* 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 URXD_RX_DATA (0xFF)
#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 = imx_get_uartclk();
if (!gd->baudrate)
gd->baudrate = CONFIG_BAUDRATE;
__REG(UART_PHYS + UFCR) = 4 << 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)
WATCHDOG_RESET();
return (__REG(UART_PHYS + URXD) & URXD_RX_DATA); /* mask out status from upper word */
}
void serial_putc (const char c)
{
__REG(UART_PHYS + UTXD) = c;
/* wait for transmitter to be ready */
while (!(__REG(UART_PHYS + UTS) & UTS_TXEMPTY))
WATCHDOG_RESET();
/* 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;
}