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Diffstat (limited to 'cpu/blackfin/serial.c')
-rw-r--r-- | cpu/blackfin/serial.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/cpu/blackfin/serial.c b/cpu/blackfin/serial.c new file mode 100644 index 0000000..0dfee51 --- /dev/null +++ b/cpu/blackfin/serial.c @@ -0,0 +1,124 @@ +/* + * U-boot - serial.c Blackfin Serial Driver + * + * Copyright (c) 2005-2008 Analog Devices Inc. + * + * Copyright (c) 2003 Bas Vermeulen <bas@buyways.nl>, + * BuyWays B.V. (www.buyways.nl) + * + * Based heavily on: + * blkfinserial.c: Serial driver for BlackFin DSP internal USRTs. + * Copyright(c) 2003 Metrowerks <mwaddel@metrowerks.com> + * Copyright(c) 2001 Tony Z. Kou <tonyko@arcturusnetworks.com> + * Copyright(c) 2001-2002 Arcturus Networks Inc. <www.arcturusnetworks.com> + * + * Based on code from 68328 version serial driver imlpementation which was: + * Copyright (C) 1995 David S. Miller <davem@caip.rutgers.edu> + * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com> + * Copyright (C) 1998, 1999 D. Jeff Dionne <jeff@uclinux.org> + * Copyright (C) 1999 Vladimir Gurevich <vgurevic@cisco.com> + * + * (C) Copyright 2000-2004 + * Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * + * Licensed under the GPL-2 or later. + */ + +#include <common.h> +#include <watchdog.h> +#include <asm/blackfin.h> +#include <asm/mach-common/bits/uart.h> + +#if defined(UART_LSR) && (CONFIG_UART_CONSOLE != 0) +# error CONFIG_UART_CONSOLE must be 0 on parts with only one UART +#endif + +#include "serial.h" + +/* Symbol for our assembly to call. */ +void serial_set_baud(uint32_t baud) +{ + serial_early_set_baud(baud); +} + +/* Symbol for common u-boot code to call. + * Setup the baudrate (brg: baudrate generator). + */ +void serial_setbrg(void) +{ + DECLARE_GLOBAL_DATA_PTR; + serial_set_baud(gd->baudrate); +} + +/* Symbol for our assembly to call. */ +void serial_initialize(void) +{ + serial_early_init(); +} + +/* Symbol for common u-boot code to call. */ +int serial_init(void) +{ + serial_initialize(); + serial_setbrg(); + return 0; +} + +void serial_putc(const char c) +{ + /* send a \r for compatibility */ + if (c == '\n') + serial_putc('\r'); + + WATCHDOG_RESET(); + + /* wait for the hardware fifo to clear up */ + while (!(*pUART_LSR & THRE)) + continue; + + /* queue the character for transmission */ + *pUART_THR = c; + SSYNC(); + + WATCHDOG_RESET(); + + /* wait for the byte to be shifted over the line */ + while (!(*pUART_LSR & TEMT)) + continue; +} + +int serial_tstc(void) +{ + WATCHDOG_RESET(); + return (*pUART_LSR & DR) ? 1 : 0; +} + +int serial_getc(void) +{ + uint16_t uart_lsr_val, uart_rbr_val; + + /* wait for data ! */ + while (!serial_tstc()) + continue; + + /* clear the status and grab the new byte */ + uart_lsr_val = *pUART_LSR; + uart_rbr_val = *pUART_RBR; + + if (uart_lsr_val & (OE|PE|FE|BI)) { + /* Some parts are read-to-clear while others are + * write-to-clear. Just do the write for everyone + * since it cant hurt (other than code size). + */ + *pUART_LSR = (OE|PE|FE|BI); + return -1; + } + + return uart_rbr_val & 0xFF; +} + +void serial_puts(const char *s) +{ + while (*s) + serial_putc(*s++); +} |