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Diffstat (limited to 'cpu/bf537/interrupts.c')
| -rw-r--r-- | cpu/bf537/interrupts.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/cpu/bf537/interrupts.c b/cpu/bf537/interrupts.c new file mode 100644 index 0000000..d2213b1 --- /dev/null +++ b/cpu/bf537/interrupts.c @@ -0,0 +1,174 @@ +/* + * U-boot - interrupts.c Interrupt related routines + * + * Copyright (c) 2005-2007 Analog Devices Inc. + * + * This file is based on interrupts.c + * Copyright 1996 Roman Zippel + * Copyright 1999 D. Jeff Dionne <jeff@uclinux.org> + * Copyright 2000-2001 Lineo, Inc. D. Jefff Dionne <jeff@lineo.ca> + * Copyright 2002 Arcturus Networks Inc. MaTed <mated@sympatico.ca> + * Copyright 2003 Metrowerks/Motorola + * Copyright 2003 Bas Vermeulen <bas@buyways.nl>, + * BuyWays B.V. (www.buyways.nl) + * + * (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., 51 Franklin St, Fifth Floor, Boston, + * MA 02110-1301 USA + */ + +#include <common.h> +#include <asm/machdep.h> +#include <asm/irq.h> +#include <config.h> +#include <asm/blackfin.h> +#include "cpu.h" + +static ulong timestamp; +static ulong last_time; +static int int_flag; + +int irq_flags; /* needed by asm-blackfin/system.h */ + +/* Functions just to satisfy the linker */ + +/* + * This function is derived from PowerPC code (read timebase as long long). + * On BF533 it just returns the timer value. + */ +unsigned long long get_ticks(void) +{ + return get_timer(0); +} + +/* + * This function is derived from PowerPC code (timebase clock frequency). + * On BF533 it returns the number of timer ticks per second. + */ +ulong get_tbclk (void) +{ + ulong tbclk; + + tbclk = CFG_HZ; + return tbclk; +} + +void enable_interrupts(void) +{ + restore_flags(int_flag); +} + +int disable_interrupts(void) +{ + save_and_cli(int_flag); + return 1; +} + +int interrupt_init(void) +{ + return (0); +} + +void udelay(unsigned long usec) +{ + unsigned long delay, start, stop; + unsigned long cclk; + cclk = (CONFIG_CCLK_HZ); + + while (usec > 1) { + /* + * how many clock ticks to delay? + * - request(in useconds) * clock_ticks(Hz) / useconds/second + */ + if (usec < 1000) { + delay = (usec * (cclk / 244)) >> 12; + usec = 0; + } else { + delay = (1000 * (cclk / 244)) >> 12; + usec -= 1000; + } + + asm volatile (" %0 = CYCLES;":"=r" (start)); + do { + asm volatile (" %0 = CYCLES; ":"=r" (stop)); + } while (stop - start < delay); + } + + return; +} + +void timer_init(void) +{ + *pTCNTL = 0x1; + *pTSCALE = 0x0; + *pTCOUNT = MAX_TIM_LOAD; + *pTPERIOD = MAX_TIM_LOAD; + *pTCNTL = 0x7; + asm("CSYNC;"); + + timestamp = 0; + last_time = 0; +} + +/* Any network command or flash + * command is started get_timer shall + * be called before TCOUNT gets reset, + * to implement the accurate timeouts. + * + * How ever milliconds doesn't return + * the number that has been elapsed from + * the last reset. + * + * As get_timer is used in the u-boot + * only for timeouts this should be + * sufficient + */ +ulong get_timer(ulong base) +{ + ulong milisec; + + /* Number of clocks elapsed */ + ulong clocks = (MAX_TIM_LOAD - (*pTCOUNT)); + + /** + * Find if the TCOUNT is reset + * timestamp gives the number of times + * TCOUNT got reset + */ + if (clocks < last_time) + timestamp++; + last_time = clocks; + + /* Get the number of milliseconds */ + milisec = clocks / (CONFIG_CCLK_HZ / 1000); + + /** + * Find the number of millisonds + * that got elapsed before this TCOUNT cycle + */ + milisec += timestamp * (MAX_TIM_LOAD / (CONFIG_CCLK_HZ / 1000)); + + return (milisec - base); +} + +void reset_timer (void) +{ + timestamp = 0; +} |