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Diffstat (limited to 'cpu/arm926ejs/mx25/serial.c')
-rw-r--r-- | cpu/arm926ejs/mx25/serial.c | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/cpu/arm926ejs/mx25/serial.c b/cpu/arm926ejs/mx25/serial.c new file mode 100644 index 0000000..17a08c3 --- /dev/null +++ b/cpu/arm926ejs/mx25/serial.c @@ -0,0 +1,231 @@ +/* + * (c) 2007 Sascha Hauer <s.hauer@pengutronix.de> + * + * (C) Copyright 2009 Freescale Semiconductor + * + * 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_MX25_UART + +#include <asm/arch/mx25.h> + +#define __REG(x) (*((volatile u32 *)(x))) + +#ifdef CONFIG_MX25_UART1 +#define UART_PHYS 0x43f90000 +#else +#error "define CONFIG_MX25_UARTx to use the mx25 UART driver" +#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 (mx25) */ + +/* 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 = mx25_get_ipg_clk(); + + 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) + ; + + /* mask out status from upper word */ + return (__REG(UART_PHYS + URXD) & URXD_RX_DATA) + ; +} + +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_MX25 */ |