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/*
* (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;
}