cpu/at91rm9200/interrupts.c

/*
 * (C) Copyright 2002
 * Lineo, Inc. <www.lineo.com>
 * Bernhard Kuhn <bkuhn@lineo.com>
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Marius Groeger <mgroeger@sysgo.de>
 *
 * (C) Copyright 2002
 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Alex Zuepke <azu@sysgo.de>
 *
 * 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 <asm/io.h>
#include <asm/arch/hardware.h>
#include <asm/proc/ptrace.h>

/* the number of clocks per CFG_HZ */
#define TIMER_LOAD_VAL (CFG_HZ_CLOCK/CFG_HZ)

/* macro to read the 16 bit timer */
#define READ_TIMER (tmr->TC_CV & 0x0000ffff)
AT91PS_TC tmr;

#ifdef CONFIG_USE_IRQ
#error There is no IRQ support for AT91RM9200 in U-Boot yet.
#else
void enable_interrupts (void)
{
	return;
}
int disable_interrupts (void)
{
	return 0;
}
#endif


void bad_mode (void)
{
	panic ("Resetting CPU ...\n");
	reset_cpu (0);
}

void show_regs (struct pt_regs *regs)
{
	unsigned long flags;
	const char *processor_modes[] = {
	"USER_26",	"FIQ_26",	"IRQ_26",	"SVC_26",
	"UK4_26",	"UK5_26",	"UK6_26",	"UK7_26",
	"UK8_26",	"UK9_26",	"UK10_26",	"UK11_26",
	"UK12_26",	"UK13_26",	"UK14_26",	"UK15_26",
	"USER_32",	"FIQ_32",	"IRQ_32",	"SVC_32",
	"UK4_32",	"UK5_32",	"UK6_32",	"ABT_32",
	"UK8_32",	"UK9_32",	"UK10_32",	"UND_32",
	"UK12_32",	"UK13_32",	"UK14_32",	"SYS_32",
	};

	flags = condition_codes (regs);

	printf ("pc : [<%08lx>]    lr : [<%08lx>]\n"
		"sp : %08lx  ip : %08lx  fp : %08lx\n",
		instruction_pointer (regs),
		regs->ARM_lr, regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
	printf ("r10: %08lx  r9 : %08lx  r8 : %08lx\n",
		regs->ARM_r10, regs->ARM_r9, regs->ARM_r8);
	printf ("r7 : %08lx  r6 : %08lx  r5 : %08lx  r4 : %08lx\n",
		regs->ARM_r7, regs->ARM_r6, regs->ARM_r5, regs->ARM_r4);
	printf ("r3 : %08lx  r2 : %08lx  r1 : %08lx  r0 : %08lx\n",
		regs->ARM_r3, regs->ARM_r2, regs->ARM_r1, regs->ARM_r0);
	printf ("Flags: %c%c%c%c",
		flags & CC_N_BIT ? 'N' : 'n',
		flags & CC_Z_BIT ? 'Z' : 'z',
		flags & CC_C_BIT ? 'C' : 'c',
		flags & CC_V_BIT ? 'V' : 'v');
	printf ("  IRQs %s  FIQs %s  Mode %s%s\n",
		interrupts_enabled (regs) ? "on" : "off",
		fast_interrupts_enabled (regs) ? "on" : "off",
		processor_modes[processor_mode (regs)],
		thumb_mode (regs) ? " (T)" : "");
}

void do_undefined_instruction (struct pt_regs *pt_regs)
{
	printf ("undefined instruction\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_software_interrupt (struct pt_regs *pt_regs)
{
	printf ("software interrupt\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_prefetch_abort (struct pt_regs *pt_regs)
{
	printf ("prefetch abort\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_data_abort (struct pt_regs *pt_regs)
{
	printf ("data abort\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_not_used (struct pt_regs *pt_regs)
{
	printf ("not used\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_fiq (struct pt_regs *pt_regs)
{
	printf ("fast interrupt request\n");
	show_regs (pt_regs);
	bad_mode ();
}

void do_irq (struct pt_regs *pt_regs)
{
	printf ("interrupt request\n");
	show_regs (pt_regs);
	bad_mode ();
}

static ulong timestamp;
static ulong lastinc;

int interrupt_init (void)
{

	tmr = AT91C_BASE_TC0;

	/* enables TC1.0 clock */
	*AT91C_PMC_PCER = 1 << AT91C_ID_TC0;  /* enable clock */

	*AT91C_TCB0_BCR = 0;
	*AT91C_TCB0_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_NONE | AT91C_TCB_TC2XC2S_NONE;
	tmr->TC_CCR = AT91C_TC_CLKDIS;
#define AT91C_TC_CMR_CPCTRG (1 << 14)
	/* set to MCLK/2 and restart the timer when the vlaue in TC_RC is reached */
	tmr->TC_CMR = AT91C_TC_TIMER_DIV1_CLOCK | AT91C_TC_CMR_CPCTRG;

	tmr->TC_IDR = ~0ul;
	tmr->TC_RC = TIMER_LOAD_VAL;
	lastinc = 0;
	tmr->TC_CCR = AT91C_TC_SWTRG | AT91C_TC_CLKEN;
	timestamp = 0;

	return (0);
}

/*
 * timer without interrupts
 */

void reset_timer (void)
{
	reset_timer_masked ();
}

ulong get_timer (ulong base)
{
	return get_timer_masked () - base;
}

void set_timer (ulong t)
{
	timestamp = t;
}

void udelay (unsigned long usec)
{
	udelay_masked(usec);
}

void reset_timer_masked (void)
{
	/* reset time */
	lastinc = READ_TIMER;
	timestamp = 0;
}

ulong get_timer_raw (void)
{
	ulong now = READ_TIMER;

	if (now >= lastinc) {
		/* normal mode */
		timestamp += now - lastinc;
	} else {
		/* we have an overflow ... */
		timestamp += now + TIMER_LOAD_VAL - lastinc;
	}
	lastinc = now;

	return timestamp;
}

ulong get_timer_masked (void)
{
	return get_timer_raw()/TIMER_LOAD_VAL;
}

void udelay_masked (unsigned long usec)
{
	ulong tmo;
	ulong endtime;
	signed long diff;

	tmo = CFG_HZ_CLOCK / 1000;
	tmo *= usec;
	tmo /= 1000;

	endtime = get_timer_raw () + tmo;

	do {
		ulong now = get_timer_raw ();
		diff = endtime - now;
	} while (diff >= 0);
}

/*
 * This function is derived from PowerPC code (read timebase as long long).
 * On ARM it just returns the timer value.
 */
unsigned long long get_ticks(void)
{
	return get_timer(0);
}

/*
 * This function is derived from PowerPC code (timebase clock frequency).
 * On ARM it returns the number of timer ticks per second.
 */
ulong get_tbclk (void)
{
	ulong tbclk;

	tbclk = CFG_HZ;
	return tbclk;
}