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Diffstat (limited to 'cpu/nios2/interrupts.c')
| -rw-r--r-- | cpu/nios2/interrupts.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/cpu/nios2/interrupts.c b/cpu/nios2/interrupts.c new file mode 100644 index 0000000..4a6da58 --- /dev/null +++ b/cpu/nios2/interrupts.c @@ -0,0 +1,229 @@ +/* + * (C) Copyright 2000-2002 + * Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * + * (C) Copyright 2004, Psyent Corporation <www.psyent.com> + * Scott McNutt <smcnutt@psyent.com> + * + * 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 <nios2.h> +#include <nios2-io.h> +#include <asm/ptrace.h> +#include <common.h> +#include <command.h> +#include <watchdog.h> +#ifdef CONFIG_STATUS_LED +#include <status_led.h> +#endif + +#if defined(CFG_NIOS_TMRBASE) && !defined(CFG_NIOS_TMRIRQ) +#error CFG_NIOS_TMRIRQ not defined (see documentation) +#endif + +/****************************************************************************/ + +struct irq_action { + interrupt_handler_t *handler; + void *arg; + int count; +}; + +static struct irq_action vecs[32]; + +/*************************************************************************/ +volatile ulong timestamp = 0; + +void reset_timer (void) +{ + timestamp = 0; +} + +ulong get_timer (ulong base) +{ + WATCHDOG_RESET (); + return (timestamp - base); +} + +void set_timer (ulong t) +{ + timestamp = t; +} + + +/* The board must handle this interrupt if a timer is not + * provided. + */ +#if defined(CFG_NIOS_TMRBASE) +void tmr_isr (void *arg) +{ + nios_timer_t *tmr = (nios_timer_t *)arg; + /* Interrupt is cleared by writing anything to the + * status register. + */ + tmr->status = 0; + timestamp += CFG_NIOS_TMRMS; +#ifdef CONFIG_STATUS_LED + status_led_tick(timestamp); +#endif +} + +static void tmr_init (void) +{ + nios_timer_t *tmr =(nios_timer_t *)CACHE_BYPASS(CFG_NIOS_TMRBASE); + + tmr->control &= ~(NIOS_TIMER_START | NIOS_TIMER_ITO); + tmr->control |= NIOS_TIMER_STOP; +#if defined(CFG_NIOS_TMRCNT) + tmr->periodl = CFG_NIOS_TMRCNT & 0xffff; + tmr->periodh = (CFG_NIOS_TMRCNT >> 16) & 0xffff; +#endif + tmr->control |= ( NIOS_TIMER_ITO | + NIOS_TIMER_CONT | + NIOS_TIMER_START ); + irq_install_handler (CFG_NIOS_TMRIRQ, tmr_isr, (void *)tmr); +} + +#endif /* CFG_NIOS_TMRBASE */ + +/*************************************************************************/ +int disable_interrupts (void) +{ + int val = rdctl (CTL_STATUS); + wrctl (CTL_STATUS, val & ~STATUS_IE); + return (val & STATUS_IE); +} + +void enable_interrupts( void ) +{ + int val = rdctl (CTL_STATUS); + wrctl (CTL_STATUS, val | STATUS_IE); +} + +void external_interrupt (struct pt_regs *regs) +{ + unsigned irqs; + struct irq_action *act; + + /* Evaluate only irqs that are both enabled AND pending */ + irqs = rdctl (CTL_IENABLE) & rdctl (CTL_IPENDING); + act = vecs; + + /* Assume (as does the Nios2 HAL) that bit 0 is highest + * priority. NOTE: There is ALWAYS a handler assigned + * (the default if no other). + */ + while (irqs) { + if (irqs & 1) { + act->handler (act->arg); + act->count++; + } + irqs >>=1; + act++; + } +} + +static void def_hdlr (void *arg) +{ + unsigned irqs = rdctl (CTL_IENABLE); + + /* Disable the individual interrupt -- with gratuitous + * warning. + */ + irqs &= ~(1 << (int)arg); + wrctl (CTL_IENABLE, irqs); + printf ("WARNING: Disabling unhandled interrupt: %d\n", + (int)arg); +} + +/*************************************************************************/ +void irq_install_handler (int irq, interrupt_handler_t *hdlr, void *arg) +{ + + int flag; + struct irq_action *act; + unsigned ena = rdctl (CTL_IENABLE); + + if ((irq < 0) || (irq > 31)) + return; + act = &vecs[irq]; + + flag = disable_interrupts (); + if (hdlr) { + act->handler = hdlr; + act->arg = arg; + ena |= (1 << irq); /* enable */ + } else { + act->handler = def_hdlr; + act->arg = (void *)irq; + ena &= ~(1 << irq); /* disable */ + } + wrctl (CTL_IENABLE, ena); + if (flag) enable_interrupts (); +} + + +int interrupt_init (void) +{ + int i; + + /* Assign the default handler to all */ + for (i = 0; i < 32; i++) { + vecs[i].handler = def_hdlr; + vecs[i].arg = (void *)i; + vecs[i].count = 0; + } + +#if defined(CFG_NIOS_TMRBASE) + tmr_init (); +#endif + + enable_interrupts (); + return (0); +} + + +/*************************************************************************/ +#if (CONFIG_COMMANDS & CFG_CMD_IRQ) +int do_irqinfo (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +{ + int i; + struct irq_action *act = vecs; + + printf ("\nInterrupt-Information:\n\n"); + printf ("Nr Routine Arg Count\n"); + printf ("-----------------------------\n"); + + for (i=0; i<32; i++) { + if (act->handler != def_hdlr) { + printf ("%02d %08lx %08lx %d\n", + i, + (ulong)act->handler, + (ulong)act->arg, + act->count); + } + act++; + } + printf ("\n"); + + return (0); +} +#endif /* CONFIG_COMMANDS & CFG_CMD_IRQ */ |