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Diffstat (limited to 'cpu/bf537/serial.c')
| -rw-r--r-- | cpu/bf537/serial.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/cpu/bf537/serial.c b/cpu/bf537/serial.c new file mode 100644 index 0000000..dd4f916 --- /dev/null +++ b/cpu/bf537/serial.c @@ -0,0 +1,194 @@ +/* + * U-boot - serial.c Serial driver for BF537 + * + * Copyright (c) 2005 blackfin.uclinux.org + * + * This file is based on + * bf537_serial.c: Serial driver for BlackFin BF537 internal UART. + * Copyright (c) 2003 Bas Vermeulen <bas@buyways.nl>, + * BuyWays B.V. (www.buyways.nl) + * + * Based heavily on blkfinserial.c + * 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. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * 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 <asm/irq.h> +#include <asm/system.h> +#include <asm/segment.h> +#include <asm/bitops.h> +#include <asm/delay.h> +#include <asm/uaccess.h> +#include <asm/io.h> +#include "serial.h" + +unsigned long pll_div_fact; + +void calc_baud(void) +{ + unsigned char i; + int temp; + u_long sclk = get_sclk(); + + for (i = 0; i < sizeof(baud_table) / sizeof(int); i++) { + temp = sclk / (baud_table[i] * 8); + if ((temp & 0x1) == 1) { + temp++; + } + temp = temp / 2; + hw_baud_table[i].dl_high = (temp >> 8) & 0xFF; + hw_baud_table[i].dl_low = (temp) & 0xFF; + } +} + +void serial_setbrg(void) +{ + int i; + DECLARE_GLOBAL_DATA_PTR; + + calc_baud(); + + for (i = 0; i < sizeof(baud_table) / sizeof(int); i++) { + if (gd->baudrate == baud_table[i]) + break; + } + + /* Enable UART */ + *pUART_GCTL |= UART_GCTL_UCEN; + sync(); + + /* Set DLAB in LCR to Access DLL and DLH */ + ACCESS_LATCH; + sync(); + + *pUART_DLL = hw_baud_table[i].dl_low; + sync(); + *pUART_DLH = hw_baud_table[i].dl_high; + sync(); + + /* Clear DLAB in LCR to Access THR RBR IER */ + ACCESS_PORT_IER; + sync(); + + /* Enable ERBFI and ELSI interrupts + * to poll SIC_ISR register*/ + *pUART_IER = UART_IER_ELSI | UART_IER_ERBFI | UART_IER_ETBEI; + sync(); + + /* Set LCR to Word Lengh 8-bit word select */ + *pUART_LCR = UART_LCR_WLS8; + sync(); + + return; +} + +int serial_init(void) +{ + serial_setbrg(); + return (0); +} + +void serial_putc(const char c) +{ + if ((*pUART_LSR) & UART_LSR_TEMT) { + if (c == '\n') + serial_putc('\r'); + + local_put_char(c); + } + + while (!((*pUART_LSR) & UART_LSR_TEMT)) + SYNC_ALL; + + return; +} + +int serial_tstc(void) +{ + if (*pUART_LSR & UART_LSR_DR) + return 1; + else + return 0; +} + +int serial_getc(void) +{ + unsigned short uart_lsr_val, uart_rbr_val; + unsigned long isr_val; + int ret; + + /* Poll for RX Interrupt */ + while (!((isr_val = + *(volatile unsigned long *)SIC_ISR) & IRQ_UART_RX_BIT)) ; + asm("csync;"); + + uart_lsr_val = *pUART_LSR; /* Clear status bit */ + uart_rbr_val = *pUART_RBR; /* getc() */ + + if (isr_val & IRQ_UART_ERROR_BIT) { + ret = -1; + } else { + ret = uart_rbr_val & 0xff; + } + + return ret; +} + +void serial_puts(const char *s) +{ + while (*s) { + serial_putc(*s++); + } +} + +static void local_put_char(char ch) +{ + int flags = 0; + unsigned long isr_val; + + save_and_cli(flags); + + /* Poll for TX Interruput */ + while (!((isr_val = *pSIC_ISR) & IRQ_UART_TX_BIT)) ; + asm("csync;"); + + *pUART_THR = ch; /* putc() */ + + if (isr_val & IRQ_UART_ERROR_BIT) { + printf("?"); + } + + restore_flags(flags); + + return; +} |