blob: 08e0675fee4035179ed6eeeccac1c4ac0aa0feef [file] [log] [blame]
/*
* (C) Copyright 2000-2002
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* (C) Copyright 2002 (440 port)
* Scott McNutt, Artesyn Communication Producs, smcnutt@artsyncp.com
*
* (C) Copyright 2003 Motorola Inc. (MPC85xx port)
* Xianghua Xiao (X.Xiao@motorola.com)
*
* (C) Copyright 2004 Freescale Semiconductor. (MPC86xx Port)
* Jeff Brown
* Srikanth Srinivasan (srikanth.srinivasan@freescale.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 <common.h>
#include <mpc86xx.h>
#include <command.h>
#include <asm/processor.h>
#include <ppc_asm.tmpl>
unsigned long decrementer_count; /* count value for 1e6/HZ microseconds */
unsigned long timestamp;
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)
{
if (val)
asm volatile ("mtdec %0"::"r" (val));
}
/* interrupt is not supported yet */
int interrupt_init_cpu(unsigned long *decrementer_count)
{
return 0;
}
int interrupt_init(void)
{
int ret;
/*
* The IRQ0 on Rev 2 is pulled high (low in Rev 1.x) to
* implement PEX10 errata. As INT is active high, it
* will cause core to take 0x500 interrupt.
*
* Due to the PIC's default pass through mode, as soon
* as interrupts are enabled (MSR[EE] = 1), an interrupt
* will be taken and u-boot will hang. This is due to a
* hardware change (per an errata fix) on new revisions
* of the board with Rev 2.x parts.
*
* Setting the PIC to mixed mode prevents the hang.
*/
if ((get_svr() & 0xf0) == 0x20) {
volatile immap_t *immr = (immap_t *)CFG_IMMR;
immr->im_pic.gcr = MPC86xx_PICGCR_RST;
while (immr->im_pic.gcr & MPC86xx_PICGCR_RST);
immr->im_pic.gcr = MPC86xx_PICGCR_MODE;
}
/* call cpu specific function from $(CPU)/interrupts.c */
ret = interrupt_init_cpu(&decrementer_count);
if (ret)
return ret;
decrementer_count = get_tbclk() / CFG_HZ;
debug("interrupt init: tbclk() = %d MHz, decrementer_count = %ld\n",
(get_tbclk() / 1000000),
decrementer_count);
set_dec(decrementer_count);
set_msr(get_msr() | MSR_EE);
debug("MSR = 0x%08lx, Decrementer reg = 0x%08lx\n",
get_msr(),
get_dec());
return 0;
}
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;
}
void increment_timestamp(void)
{
timestamp++;
}
/*
* timer_interrupt - gets called when the decrementer overflows,
* with interrupts disabled.
* Trivial implementation - no need to be really accurate.
*/
void timer_interrupt_cpu(struct pt_regs *regs)
{
/* nothing to do here */
}
void timer_interrupt(struct pt_regs *regs)
{
/* call cpu specific function from $(CPU)/interrupts.c */
timer_interrupt_cpu(regs);
timestamp++;
ppcDcbf((unsigned long)&timestamp);
/* Restore Decrementer Count */
set_dec(decrementer_count);
#if defined(CONFIG_WATCHDOG) || defined (CONFIG_HW_WATCHDOG)
if ((timestamp % (CFG_WATCHDOG_FREQ)) == 0)
WATCHDOG_RESET();
#endif /* CONFIG_WATCHDOG || CONFIG_HW_WATCHDOG */
#ifdef CONFIG_STATUS_LED
status_led_tick(timestamp);
#endif /* CONFIG_STATUS_LED */
#ifdef CONFIG_SHOW_ACTIVITY
board_show_activity(timestamp);
#endif /* CONFIG_SHOW_ACTIVITY */
}
void reset_timer(void)
{
timestamp = 0;
}
ulong get_timer(ulong base)
{
return timestamp - base;
}
void set_timer(ulong t)
{
timestamp = t;
}
/*
* Install and free a interrupt handler. Not implemented yet.
*/
void irq_install_handler(int vec, interrupt_handler_t *handler, void *arg)
{
}
void irq_free_handler(int vec)
{
}
/*
* irqinfo - print information about PCI devices,not implemented.
*/
int do_irqinfo(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
printf("\nInterrupt-unsupported:\n");
return 0;
}
/*
* Handle external interrupts
*/
void external_interrupt(struct pt_regs *regs)
{
puts("external_interrupt (oops!)\n");
}