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Diffstat (limited to 'cpu/mpc5xx/interrupts.c')
| -rw-r--r-- | cpu/mpc5xx/interrupts.c | 273 |
1 files changed, 273 insertions, 0 deletions
diff --git a/cpu/mpc5xx/interrupts.c b/cpu/mpc5xx/interrupts.c new file mode 100644 index 000000000..282c3165d --- /dev/null +++ b/cpu/mpc5xx/interrupts.c @@ -0,0 +1,273 @@ +/* + * (C) Copyright 2000-2002 Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * (C) Copyright 2003 Martin Winistoerfer, martinwinistoerfer@gmx.ch. + * + * 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, + */ + +/* + * File: interrupt.c + * + * Discription: Contains interrupt routines needed by U-Boot + * + */ + +#include <common.h> +#include <watchdog.h> +#include <mpc5xx.h> +#include <asm/processor.h> + +/************************************************************************/ + +unsigned decrementer_count; /* count value for 1e6/HZ microseconds */ + +/************************************************************************/ + +struct interrupt_action { + interrupt_handler_t *handler; + void *arg; +}; + +static struct interrupt_action irq_vecs[NR_IRQS]; + +/* + * Local function prototypes + */ +static __inline__ unsigned long get_msr (void) +{ + unsigned long msr; + + asm volatile ("mfmsr %0":"=r" (msr):); + + return msr; +} + +static __inline__ void set_msr (unsigned long msr) +{ + asm volatile ("mtmsr %0"::"r" (msr)); +} + +static __inline__ unsigned long get_dec (void) +{ + unsigned long val; + + asm volatile ("mfdec %0":"=r" (val):); + + return val; +} + + +static __inline__ void set_dec (unsigned long val) +{ + asm volatile ("mtdec %0"::"r" (val)); +} + +/* + * Enable interrupts + */ +void enable_interrupts (void) +{ + set_msr (get_msr () | MSR_EE); +} + +/* + * Returns flag if MSR_EE was set before + */ +int disable_interrupts (void) +{ + ulong msr = get_msr (); + + set_msr (msr & ~MSR_EE); + return ((msr & MSR_EE) != 0); +} + +/* + * Initialise interrupts + */ + +int interrupt_init (void) +{ + volatile immap_t *immr = (immap_t *) CFG_IMMR; + + /* Decrementer used here for status led */ + decrementer_count = get_tbclk () / CFG_HZ; + + /* Disable all interrupts */ + immr->im_siu_conf.sc_simask = 0; + + set_dec (decrementer_count); + + set_msr (get_msr () | MSR_EE); + return (0); +} + +/* + * Handle external interrupts + */ +void external_interrupt (struct pt_regs *regs) +{ + volatile immap_t *immr = (immap_t *) CFG_IMMR; + int irq; + ulong simask, newmask; + ulong vec, v_bit; + + /* + * read the SIVEC register and shift the bits down + * to get the irq number + */ + vec = immr->im_siu_conf.sc_sivec; + irq = vec >> 26; + v_bit = 0x80000000UL >> irq; + + /* + * Read Interrupt Mask Register and Mask Interrupts + */ + simask = immr->im_siu_conf.sc_simask; + newmask = simask & (~(0xFFFF0000 >> irq)); + immr->im_siu_conf.sc_simask = newmask; + + if (!(irq & 0x1)) { /* External Interrupt ? */ + ulong siel; + + /* + * Read Interrupt Edge/Level Register + */ + siel = immr->im_siu_conf.sc_siel; + + if (siel & v_bit) { /* edge triggered interrupt ? */ + /* + * Rewrite SIPEND Register to clear interrupt + */ + immr->im_siu_conf.sc_sipend = v_bit; + } + } + + if (irq_vecs[irq].handler != NULL) { + irq_vecs[irq].handler (irq_vecs[irq].arg); + } else { + printf ("\nBogus External Interrupt IRQ %d Vector %ld\n", + irq, vec); + /* turn off the bogus interrupt to avoid it from now */ + simask &= ~v_bit; + } + /* + * Re-Enable old Interrupt Mask + */ + immr->im_siu_conf.sc_simask = simask; +} + +/* + * Install and free an interrupt handler + */ +void irq_install_handler (int vec, interrupt_handler_t * handler, + void *arg) +{ + volatile immap_t *immr = (immap_t *) CFG_IMMR; + /* SIU interrupt */ + if (irq_vecs[vec].handler != NULL) { + printf ("SIU interrupt %d 0x%x\n", + vec, + (uint) handler); + } + irq_vecs[vec].handler = handler; + irq_vecs[vec].arg = arg; + immr->im_siu_conf.sc_simask |= 1 << (31 - vec); +#if 0 + printf ("Install SIU interrupt for vector %d ==> %p\n", + vec, handler); +#endif +} + +void irq_free_handler (int vec) +{ + volatile immap_t *immr = (immap_t *) CFG_IMMR; + /* SIU interrupt */ +#if 0 + printf ("Free CPM interrupt for vector %d\n", + vec); +#endif + immr->im_siu_conf.sc_simask &= ~(1 << (31 - vec)); + irq_vecs[vec].handler = NULL; + irq_vecs[vec].arg = NULL; +} + +volatile ulong timestamp = 0; + +/* + * Timer interrupt - gets called when bit 0 of DEC changes from + * 0. Decrementer is enabled with bit TBE in TBSCR. + */ +void timer_interrupt (struct pt_regs *regs) +{ + volatile immap_t *immr = (immap_t *) CFG_IMMR; + +#ifdef CONFIG_STATUS_LED + extern void status_led_tick (ulong); +#endif +#if 0 + printf ("*** Timer Interrupt *** "); +#endif + /* Reset Timer Status Bit and Timers Interrupt Status */ + immr->im_clkrstk.cark_plprcrk = KAPWR_KEY; + __asm__ ("nop"); + immr->im_clkrst.car_plprcr |= PLPRCR_TEXPS | PLPRCR_TMIST; + + /* Restore Decrementer Count */ + set_dec (decrementer_count); + + timestamp++; + +#ifdef CONFIG_STATUS_LED + status_led_tick (timestamp); +#endif /* CONFIG_STATUS_LED */ + +#if defined(CONFIG_WATCHDOG) + /* + * The shortest watchdog period of all boards + * is approx. 1 sec, thus re-trigger watchdog at least + * every 500 ms = CFG_HZ / 2 + */ + if ((timestamp % (CFG_HZ / 2)) == 0) { + reset_5xx_watchdog (immr); + } +#endif /* CONFIG_WATCHDOG */ +} + +/* + * Reset timer + */ +void reset_timer (void) +{ + timestamp = 0; +} + +/* + * Get Timer + */ +ulong get_timer (ulong base) +{ + return (timestamp - base); +} + +/* + * Set timer + */ +void set_timer (ulong t) +{ + timestamp = t; +} |