diff options
Diffstat (limited to 'cpu/nios/interrupts.c')
| -rw-r--r-- | cpu/nios/interrupts.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/cpu/nios/interrupts.c b/cpu/nios/interrupts.c new file mode 100644 index 0000000..981b8f7 --- /dev/null +++ b/cpu/nios/interrupts.c @@ -0,0 +1,184 @@ +/* + * (C) Copyright 2000-2002 + * Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * + * (C) Copyright 2003, 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 <nios.h> +#include <nios-io.h> +#include <asm/ptrace.h> +#include <common.h> +#include <command.h> + +/****************************************************************************/ + +struct irq_action { + interrupt_handler_t *handler; + void *arg; + int count; +}; + +static struct irq_action irq_vecs[64]; + +/*************************************************************************/ +volatile ulong timestamp = 0; + +void reset_timer (void) +{ + timestamp = 0; +} + +ulong get_timer (ulong base) +{ + 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 timer_interrupt (struct pt_regs *regs) +{ + /* Interrupt is cleared by writing anything to the + * status register. + */ + nios_timer_t *tmr = (nios_timer_t *)CFG_NIOS_TMRBASE; + tmr->status = 0; + timestamp += CFG_NIOS_TMRMS; +} +#endif + +/*************************************************************************/ +int disable_interrupts (void) +{ + int val = 0; + + /* Writing anything to CLR_IE disables interrupts */ + val = rdctl (CTL_STATUS); + wrctl (CTL_CLR_IE, 0); + return (val & STATUS_IE); +} + +void enable_interrupts( void ) +{ + /* Writing anything SET_IE enables interrupts */ + wrctl (CTL_SET_IE, 0); +} + +void external_interrupt (struct pt_regs *regs) +{ + unsigned vec; + + vec = (regs->status & STATUS_IPRI) >> 9; /* ipri */ + + irq_vecs[vec].count++; + if (irq_vecs[vec].handler != NULL) { + (*irq_vecs[vec].handler)(irq_vecs[vec].arg); + } else { + /* A sad side-effect of masking a bogus interrupt is + * that lower priority interrupts will also be disabled. + * This is probably not what we want ... so hang insted. + */ + printf ("Unhandled interrupt: 0x%x\n", vec); + disable_interrupts (); + hang (); + } +} + +/*************************************************************************/ +int interrupt_init (void) +{ + int vec; + +#if defined(CFG_NIOS_TMRBASE) + nios_timer_t *tmr = (nios_timer_t *)CFG_NIOS_TMRBASE; + + tmr->control &= ~NIOS_TIMER_ITO; + tmr->control |= NIOS_TIMER_STOP; +#endif + + for (vec=0; vec<64; vec++ ) { + irq_vecs[vec].handler = NULL; + irq_vecs[vec].arg = NULL; + irq_vecs[vec].count = 0; + } + + /* Need timus interruptus -- start the lopri timer */ +#if defined(CFG_NIOS_TMRBASE) + tmr->control |= ( NIOS_TIMER_ITO | + NIOS_TIMER_CONT | + NIOS_TIMER_START ); + ipri (CFG_NIOS_TMRIRQ + 1); +#endif + enable_interrupts (); + return (0); +} + +void irq_install_handler (int vec, interrupt_handler_t *handler, void *arg) +{ + struct irq_action *irqa = irq_vecs; + int i = vec; + int flag; + + if (irqa[i].handler != NULL) { + printf ("Interrupt vector %d: handler 0x%x " + "replacing 0x%x\n", + vec, (uint)handler, (uint)irqa[i].handler); + } + + flag = disable_interrupts (); + irqa[i].handler = handler; + irqa[i].arg = arg; + if (flag ) + enable_interrupts (); +} + +/*************************************************************************/ +#if (CONFIG_COMMANDS & CFG_CMD_IRQ) +int do_irqinfo (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +{ + int vec; + + printf ("\nInterrupt-Information:\n"); + printf ("Nr Routine Arg CouIt's ok to cnt\n"); + + for (vec=0; vec<64; vec++) { + if (irq_vecs[vec].handler != NULL) { + printf ("%02d %08lx %08lx %d\n", + vec, + (ulong)irq_vecs[vec].handler<<1, + (ulong)irq_vecs[vec].arg, + irq_vecs[vec].count); + } + } + + return (0); +} +#endif /* CONFIG_COMMANDS & CFG_CMD_IRQ */ |