diff options
Diffstat (limited to 'core/drivers/imx_uart.c')
-rw-r--r-- | core/drivers/imx_uart.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/core/drivers/imx_uart.c b/core/drivers/imx_uart.c new file mode 100644 index 0000000..b66d905 --- /dev/null +++ b/core/drivers/imx_uart.c @@ -0,0 +1,112 @@ +/* + * Copyright (C) 2015 Freescale Semiconductor, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <platform_config.h> + +#include <drivers/imx_uart.h> +#include <console.h> +#include <io.h> +#include <compiler.h> + +/* 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 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 */ + +void imx_uart_init(vaddr_t __unused vbase) +{ + /* + * Do nothing, debug uart(uart0) share with normal world, + * everything for uart0 intialization is done in bootloader. + */ +} + +void imx_uart_flush_tx_fifo(vaddr_t base) +{ + while (!(read32(base + UTS) & UTS_TXEMPTY)) + ; +} + +int imx_uart_getchar(vaddr_t base) +{ + while (read32(base + UTS) & UTS_RXEMPTY) + ; + + return (read32(base + URXD) & URXD_RX_DATA); +} + +void imx_uart_putc(const char c, vaddr_t base) +{ + write32(c, base + UTXD); + + /* wait until sent */ + while (!(read32(base + UTS) & UTS_TXEMPTY)) + ; +} |