arch/nios2/cpu/interrupts.c - github/trini/u-boot - Gitiles

 /*
  * (C) Copyright 2000-2002
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * (C) Copyright 2004, 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 <nios2.h>
 #include <nios2-io.h>
 #include <asm/types.h>
 #include <asm/io.h>
 #include <asm/ptrace.h>
 #include <common.h>
 #include <command.h>
 #include <watchdog.h>
 #ifdef CONFIG_STATUS_LED
 #include <status_led.h>
 #endif

 #if defined(CONFIG_SYS_NIOS_TMRBASE) && !defined(CONFIG_SYS_NIOS_TMRIRQ)
 #error CONFIG_SYS_NIOS_TMRIRQ not defined (see documentation)
 #endif

 /****************************************************************************/

 struct	irq_action {
 	interrupt_handler_t *handler;
 	void *arg;
 	int count;
 };

 static struct irq_action vecs[32];

 /*************************************************************************/
 volatile ulong timestamp = 0;

 void reset_timer (void)
 {
 	nios_timer_t *tmr =(nios_timer_t *)CONFIG_SYS_NIOS_TMRBASE;

 	/* From Embedded Peripherals Handbook:
 	 *
 	 * "When the hardware is configured with Writeable period
 	 * disabled, writing to one of the period_n registers causes
 	 * the counter to reset to the fixed Timeout Period specified
 	 * at system generation time."
 	 *
 	 * Here we force a reload to prevent early timeouts from
 	 * get_timer() when the interrupt period is greater than
 	 * than 1 msec.
 	 *
 	 * Simply write to periodl with its own value to force an
 	 * internal counter reload, THEN reset the timestamp.
 	 */
 	writel (readl (&tmr->periodl), &tmr->periodl);
 	timestamp = 0;

 	/* From Embedded Peripherals Handbook:
 	 *
 	 * "Writing to one of the period_n registers stops the internal
 	 * counter, except when the hardware is configured with Start/Stop
 	 * control bits off. If Start/Stop control bits is off, writing
 	 * either register does not stop the counter."
 	 *
 	 * In order to accomodate either configuration, the control
 	 * register is re-written. If the counter is stopped, it will
 	 * be restarted. If it is running, the write is essentially
 	 * a nop.
 	 */
 	writel (NIOS_TIMER_ITO | NIOS_TIMER_CONT | NIOS_TIMER_START,
 			&tmr->control);

 }

 ulong get_timer (ulong base)
 {
 	WATCHDOG_RESET ();
 	return (timestamp - base);
 }

 /* The board must handle this interrupt if a timer is not
  * provided.
  */
 #if defined(CONFIG_SYS_NIOS_TMRBASE)
 void tmr_isr (void *arg)
 {
 	nios_timer_t *tmr = (nios_timer_t *)arg;
 	/* Interrupt is cleared by writing anything to the
 	 * status register.
 	 */
 	writel (0, &tmr->status);
 	timestamp += CONFIG_SYS_NIOS_TMRMS;
 #ifdef CONFIG_STATUS_LED
 	status_led_tick(timestamp);
 #endif
 }

 static void tmr_init (void)
 {
 	nios_timer_t *tmr =(nios_timer_t *)CONFIG_SYS_NIOS_TMRBASE;

 	writel (0, &tmr->status);
 	writel (0, &tmr->control);
 	writel (NIOS_TIMER_STOP, &tmr->control);

 #if defined(CONFIG_SYS_NIOS_TMRCNT)
 	writel (CONFIG_SYS_NIOS_TMRCNT & 0xffff, &tmr->periodl);
 	writel ((CONFIG_SYS_NIOS_TMRCNT >> 16) & 0xffff, &tmr->periodh);
 #endif
 	writel (NIOS_TIMER_ITO | NIOS_TIMER_CONT | NIOS_TIMER_START,
 			&tmr->control);
 	irq_install_handler (CONFIG_SYS_NIOS_TMRIRQ, tmr_isr, (void *)tmr);
 }

 #endif /* CONFIG_SYS_NIOS_TMRBASE */

 /*************************************************************************/
 int disable_interrupts (void)
 {
 	int val = rdctl (CTL_STATUS);
 	wrctl (CTL_STATUS, val & ~STATUS_IE);
 	return (val & STATUS_IE);
 }

 void enable_interrupts( void )
 {
 	int val = rdctl (CTL_STATUS);
 	wrctl (CTL_STATUS, val | STATUS_IE);
 }

 void external_interrupt (struct pt_regs *regs)
 {
 	unsigned irqs;
 	struct irq_action *act;

 	/* Evaluate only irqs that are both enabled AND pending */
 	irqs = rdctl (CTL_IENABLE) & rdctl (CTL_IPENDING);
 	act = vecs;

 	/* Assume (as does the Nios2 HAL) that bit 0 is highest
 	 * priority. NOTE: There is ALWAYS a handler assigned
 	 * (the default if no other).
 	 */
 	while (irqs) {
 		if (irqs & 1) {
 			act->handler (act->arg);
 			act->count++;
 		}
 		irqs >>=1;
 		act++;
 	}
 }

 static void def_hdlr (void *arg)
 {
 	unsigned irqs = rdctl (CTL_IENABLE);

 	/* Disable the individual interrupt -- with gratuitous
 	 * warning.
 	 */
 	irqs &= ~(1 << (int)arg);
 	wrctl (CTL_IENABLE, irqs);
 	printf ("WARNING: Disabling unhandled interrupt: %d\n",
 			(int)arg);
 }

 /*************************************************************************/
 void irq_install_handler (int irq, interrupt_handler_t *hdlr, void *arg)
 {

 	int flag;
 	struct irq_action *act;
 	unsigned ena = rdctl (CTL_IENABLE);

 	if ((irq < 0) || (irq > 31))
 		return;
 	act = &vecs[irq];

 	flag = disable_interrupts ();
 	if (hdlr) {
 		act->handler = hdlr;
 		act->arg = arg;
 		ena |= (1 << irq);		/* enable */
 	} else {
 		act->handler = def_hdlr;
 		act->arg = (void *)irq;
 		ena &= ~(1 << irq);		/* disable */
 	}
 	wrctl (CTL_IENABLE, ena);
 	if (flag) enable_interrupts ();
 }


 int interrupt_init (void)
 {
 	int i;

 	/* Assign the default handler to all */
 	for (i = 0; i < 32; i++) {
 		vecs[i].handler = def_hdlr;
 		vecs[i].arg = (void *)i;
 		vecs[i].count = 0;
 	}

 #if defined(CONFIG_SYS_NIOS_TMRBASE)
 	tmr_init ();
 #endif

 	enable_interrupts ();
 	return (0);
 }


 /*************************************************************************/
 #if defined(CONFIG_CMD_IRQ)
 int do_irqinfo (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	int i;
 	struct irq_action *act = vecs;

 	printf ("\nInterrupt-Information:\n\n");
 	printf ("Nr  Routine   Arg       Count\n");
 	printf ("-----------------------------\n");

 	for (i=0; i<32; i++) {
 		if (act->handler != def_hdlr) {
 			printf ("%02d  %08lx  %08lx  %d\n",
 				i,
 				(ulong)act->handler,
 				(ulong)act->arg,
 				act->count);
 		}
 		act++;
 	}
 	printf ("\n");

 	return (0);
 }
 #endif
	/*
	* (C) Copyright 2000-2002
	* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
	*
	* (C) Copyright 2004, 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 <nios2.h>
	#include <nios2-io.h>
	#include <asm/types.h>
	#include <asm/io.h>
	#include <asm/ptrace.h>
	#include <common.h>
	#include <command.h>
	#include <watchdog.h>
	#ifdef CONFIG_STATUS_LED
	#include <status_led.h>
	#endif

	#if defined(CONFIG_SYS_NIOS_TMRBASE) && !defined(CONFIG_SYS_NIOS_TMRIRQ)
	#error CONFIG_SYS_NIOS_TMRIRQ not defined (see documentation)
	#endif

	/****************************************************************************/

	struct irq_action {
	interrupt_handler_t *handler;
	void *arg;
	int count;
	};

	static struct irq_action vecs[32];

	/*************************************************************************/
	volatile ulong timestamp = 0;

	void reset_timer (void)
	{
	nios_timer_t tmr =(nios_timer_t )CONFIG_SYS_NIOS_TMRBASE;

	/* From Embedded Peripherals Handbook:
	*
	* "When the hardware is configured with Writeable period
	* disabled, writing to one of the period_n registers causes
	* the counter to reset to the fixed Timeout Period specified
	* at system generation time."
	*
	* Here we force a reload to prevent early timeouts from
	* get_timer() when the interrupt period is greater than
	* than 1 msec.
	*
	* Simply write to periodl with its own value to force an
	* internal counter reload, THEN reset the timestamp.
	*/
	writel (readl (&tmr->periodl), &tmr->periodl);
	timestamp = 0;

	/* From Embedded Peripherals Handbook:
	*
	* "Writing to one of the period_n registers stops the internal
	* counter, except when the hardware is configured with Start/Stop
	* control bits off. If Start/Stop control bits is off, writing
	* either register does not stop the counter."
	*
	* In order to accomodate either configuration, the control
	* register is re-written. If the counter is stopped, it will
	* be restarted. If it is running, the write is essentially
	* a nop.
	*/
	writel (NIOS_TIMER_ITO \| NIOS_TIMER_CONT \| NIOS_TIMER_START,
	&tmr->control);

	}

	ulong get_timer (ulong base)
	{
	WATCHDOG_RESET ();
	return (timestamp - base);
	}

	/* The board must handle this interrupt if a timer is not
	* provided.
	*/
	#if defined(CONFIG_SYS_NIOS_TMRBASE)
	void tmr_isr (void *arg)
	{
	nios_timer_t tmr = (nios_timer_t )arg;
	/* Interrupt is cleared by writing anything to the
	* status register.
	*/
	writel (0, &tmr->status);
	timestamp += CONFIG_SYS_NIOS_TMRMS;
	#ifdef CONFIG_STATUS_LED
	status_led_tick(timestamp);
	#endif
	}

	static void tmr_init (void)
	{
	nios_timer_t tmr =(nios_timer_t )CONFIG_SYS_NIOS_TMRBASE;

	writel (0, &tmr->status);
	writel (0, &tmr->control);
	writel (NIOS_TIMER_STOP, &tmr->control);

	#if defined(CONFIG_SYS_NIOS_TMRCNT)
	writel (CONFIG_SYS_NIOS_TMRCNT & 0xffff, &tmr->periodl);
	writel ((CONFIG_SYS_NIOS_TMRCNT >> 16) & 0xffff, &tmr->periodh);
	#endif
	writel (NIOS_TIMER_ITO \| NIOS_TIMER_CONT \| NIOS_TIMER_START,
	&tmr->control);
	irq_install_handler (CONFIG_SYS_NIOS_TMRIRQ, tmr_isr, (void *)tmr);
	}

	#endif /* CONFIG_SYS_NIOS_TMRBASE */

	/*************************************************************************/
	int disable_interrupts (void)
	{
	int val = rdctl (CTL_STATUS);
	wrctl (CTL_STATUS, val & ~STATUS_IE);
	return (val & STATUS_IE);
	}

	void enable_interrupts( void )
	{
	int val = rdctl (CTL_STATUS);
	wrctl (CTL_STATUS, val \| STATUS_IE);
	}

	void external_interrupt (struct pt_regs *regs)
	{
	unsigned irqs;
	struct irq_action *act;

	/* Evaluate only irqs that are both enabled AND pending */
	irqs = rdctl (CTL_IENABLE) & rdctl (CTL_IPENDING);
	act = vecs;

	/* Assume (as does the Nios2 HAL) that bit 0 is highest
	* priority. NOTE: There is ALWAYS a handler assigned
	* (the default if no other).
	*/
	while (irqs) {
	if (irqs & 1) {
	act->handler (act->arg);
	act->count++;
	}
	irqs >>=1;
	act++;
	}
	}

	static void def_hdlr (void *arg)
	{
	unsigned irqs = rdctl (CTL_IENABLE);

	/* Disable the individual interrupt -- with gratuitous
	* warning.
	*/
	irqs &= ~(1 << (int)arg);
	wrctl (CTL_IENABLE, irqs);
	printf ("WARNING: Disabling unhandled interrupt: %d\n",
	(int)arg);
	}

	/*************************************************************************/
	void irq_install_handler (int irq, interrupt_handler_t hdlr, void arg)
	{

	int flag;
	struct irq_action *act;
	unsigned ena = rdctl (CTL_IENABLE);

	if ((irq < 0) \|\| (irq > 31))
	return;
	act = &vecs[irq];

	flag = disable_interrupts ();
	if (hdlr) {
	act->handler = hdlr;
	act->arg = arg;
	ena \|= (1 << irq); /* enable */
	} else {
	act->handler = def_hdlr;
	act->arg = (void *)irq;
	ena &= ~(1 << irq); /* disable */
	}
	wrctl (CTL_IENABLE, ena);
	if (flag) enable_interrupts ();
	}


	int interrupt_init (void)
	{
	int i;

	/* Assign the default handler to all */
	for (i = 0; i < 32; i++) {
	vecs[i].handler = def_hdlr;
	vecs[i].arg = (void *)i;
	vecs[i].count = 0;
	}

	#if defined(CONFIG_SYS_NIOS_TMRBASE)
	tmr_init ();
	#endif

	enable_interrupts ();
	return (0);
	}


	/*************************************************************************/
	#if defined(CONFIG_CMD_IRQ)
	int do_irqinfo (cmd_tbl_t cmdtp, int flag, int argc, char const argv[])
	{
	int i;
	struct irq_action *act = vecs;

	printf ("\nInterrupt-Information:\n\n");
	printf ("Nr Routine Arg Count\n");
	printf ("-----------------------------\n");

	for (i=0; i<32; i++) {
	if (act->handler != def_hdlr) {
	printf ("%02d %08lx %08lx %d\n",
	i,
	(ulong)act->handler,
	(ulong)act->arg,
	act->count);
	}
	act++;
	}
	printf ("\n");

	return (0);
	}
	#endif