NetBSD/sys/arch/arm/xscale/pxa2x0_intr.c

/* $NetBSD: pxa2x0_intr.c,v 1.1 2002/10/19 19:31:39 bsh Exp $ */

/*
 * Copyright (c) 2002  Genetec Corporation.  All rights reserved.
 * Written by Hiroyuki Bessho for Genetec Corporation.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed for the NetBSD Project by
 *	Genetec Corporation.
 * 4. The name of Genetec Corporation may not be used to endorse or 
 *    promote products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY GENETEC CORPORATION ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL GENETEC CORPORATION
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * IRQ handler for the Intel PXA2X0 processor.
 * It has integrated interrupt controller.
 */
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <uvm/uvm_extern.h>
#include <machine/bus.h>
#include <machine/intr.h>
#include <arm/cpufunc.h>

#include <arm/xscale/pxa2x0reg.h>
#include <arm/xscale/pxa2x0var.h>
#include <arm/sa11x0/sa11x0_var.h>
#include <arm/xscale/pxa2x0_intr.h>

/*
 * interrupt dispatch table. 
 */
#ifdef MULTIPLE_HANDLERS_ON_ONE_IRQ
struct intrhand {
	TAILQ_ENTRY(intrhand) ih_list;	/* link on intrq list */
	int (*ih_func)(void *);		/* handler */
	void *ih_arg;			/* arg for handler */
};
#endif

static struct {
#ifdef MULTIPLE_HANDLERS_ON_ONE_IRQ
	TAILQ_HEAD(,intrhand) list;
#else
	pxa2x0_irq_handler_t func;
#endif
	void *cookie;		/* NULL for stackframe */
	/* struct evbnt ev; */
} handler[ICU_LEN];

__volatile int softint_pending;

__volatile int current_spl_level;
__volatile int intr_mask;
/* interrupt masks for each level */
int pxa2x0_imask[NIPL];
static int extirq_level[ICU_LEN];

int current_intr_depth;

static __inline void
__raise(int ipl)
{
	if( current_spl_level < ipl ){
		pxa2x0_setipl(ipl);
	}
}


/*
 * Map a software interrupt queue to an interrupt priority level.
 */
static const int si_to_ipl[SI_NQUEUES] = {
	IPL_SOFT,		/* SI_SOFT */
	IPL_SOFTCLOCK,		/* SI_SOFTCLOCK */
	IPL_SOFTNET,		/* SI_SOFTNET */
	IPL_SOFTSERIAL,		/* SI_SOFTSERIAL */
};

/*
 * called from irq_entry.
 */
void
pxa2x0_irq_handler(struct clockframe *frame)
{
	uint32_t irqbits;
	int irqno;
	int saved_spl_level;

	++current_intr_depth;
	saved_spl_level = current_spl_level;

	/* get pending IRQs */
	irqbits = read_icu(SAIPIC_IP);

	while( (irqno = find_first_bit(irqbits)) >= 0 ){
		/* XXX: Shuould we handle IRQs in priority order? */

		/* raise spl to stop interrupts of lower priorities */
		if( saved_spl_level < extirq_level[irqno] )
			pxa2x0_setipl(extirq_level[irqno]);

#ifdef notyet
		/* Enable interrupt */
#endif
#ifndef MULTIPLE_HANDLERS_ON_ONE_IRQ
		(* handler[irqno].func)( 
			handler[irqno].cookie == 0
			? frame : handler[irqno].cookie );
#else
		/* process all handlers for this interrupt.
		   XXX not yet */
#endif
		
#ifdef notyet
		/* Disable interrupt */
#endif

		irqbits &= ~(1<<irqno);
	}

	/* restore spl to that was when this interrupt happen */
	pxa2x0_setipl(saved_spl_level);
			
	if( softint_pending & intr_mask )
		pxa2x0_do_pending();

	--current_intr_depth;
}

static int
stray_interrupt( void *cookie )
{
	int irqno = (int)cookie;
	printf( "stray interrupt %d\n", irqno );

	if( PXA2X0_IRQ_MIN <= irqno && irqno < ICU_LEN ){
		int save = disable_interrupts(I32_bit);
		write_icu( SAIPIC_MR,
			   read_icu(SAIPIC_MR) & ~(1U<<irqno) );
		restore_interrupts(save);
	}

	return 0;
}



/*
 * Interrupt Mask Handling
 */

void
pxa2x0_update_intr_masks( int irqno, int level )
{
	int mask = 1U<<irqno;
	int psw = disable_interrupts(I32_bit);
	int i;


	for( i=IPL_BIO; i < level; ++i )
		pxa2x0_imask[i] |= mask; /* Enable interrupt at lower level */
	for( ; i < NIPL-1; ++i )
		pxa2x0_imask[i] &= ~mask; /* Disable itnerrupt at upper level */

	/*
	 * Enforce a heirarchy that gives "slow" device (or devices with
	 * limited input buffer space/"real-time" requirements) a better
	 * chance at not dropping data.
	 */
	pxa2x0_imask[IPL_BIO] &= pxa2x0_imask[IPL_SOFTNET];
	pxa2x0_imask[IPL_NET] &= pxa2x0_imask[IPL_BIO];
	pxa2x0_imask[IPL_SOFTSERIAL] &= pxa2x0_imask[IPL_NET];
	pxa2x0_imask[IPL_TTY] &= pxa2x0_imask[IPL_SOFTSERIAL];

	/*
	 * splvm() blocks all interrupts that use the kernel memory
	 * allocation facilities.
	 */
	pxa2x0_imask[IPL_IMP] &= pxa2x0_imask[IPL_TTY];

	/*
	 * Audio devices are not allowed to perform memory allocation
	 * in their interrupt routines, and they have fairly "real-time"
	 * requirements, so give them a high interrupt priority.
	 */
	pxa2x0_imask[IPL_AUDIO] &= pxa2x0_imask[IPL_IMP];

	/*
	 * splclock() must block anything that uses the scheduler.
	 */
	pxa2x0_imask[IPL_CLOCK] &= pxa2x0_imask[IPL_AUDIO];

	/*
	 * splhigh() must block "everything".
	 */
	pxa2x0_imask[IPL_HIGH] &= pxa2x0_imask[IPL_STATCLOCK];

	/*
	 * XXX We need serial drivers to run at the absolute highest priority
	 * in order to avoid overruns, so serial > high.
	 */
	pxa2x0_imask[IPL_SERIAL] &= pxa2x0_imask[IPL_HIGH];

	write_icu( SAIPIC_MR, pxa2x0_imask[current_spl_level] );

	restore_interrupts(psw);
}


static void
init_interrupt_masks(void)
{
	int i;
	pxa2x0_imask[IPL_NONE] = 0xffffffff;

	for( i = IPL_BIO; i < NIPL; ++i )
		pxa2x0_imask[i] = 0;

	/*
	 * Initialize the soft interrupt masks to block themselves.
	 */
	pxa2x0_imask[IPL_SOFT] = ~SI_TO_IRQBIT(SI_SOFT);
	pxa2x0_imask[IPL_SOFTCLOCK] = ~SI_TO_IRQBIT(SI_SOFTCLOCK);
	pxa2x0_imask[IPL_SOFTNET] = ~SI_TO_IRQBIT(SI_SOFTNET);
	pxa2x0_imask[IPL_SOFTSERIAL] = ~SI_TO_IRQBIT(SI_SOFTSERIAL);

	/*
	 * splsoftclock() is the only interface that users of the
	 * generic software interrupt facility have to block their
	 * soft intrs, so splsoftclock() must also block IPL_SOFT.
	 */
	pxa2x0_imask[IPL_SOFTCLOCK] &= pxa2x0_imask[IPL_SOFT];

	/*
	 * splsoftnet() must also block splsoftclock(), since we don't
	 * want timer-driven network events to occur while we're
	 * processing incoming packets.
	 */
	pxa2x0_imask[IPL_SOFTNET] &= pxa2x0_imask[IPL_SOFTCLOCK];
	
}

void
pxa2x0_do_pending(void)
{
	static __cpu_simple_lock_t processing = __SIMPLELOCK_UNLOCKED;
	int oldirqstate, spl_save;

	if (__cpu_simple_lock_try(&processing) == 0)
		return;

	spl_save = current_spl_level;

	oldirqstate = disable_interrupts(I32_bit);

#if 1
#define	DO_SOFTINT(si,ipl)						\
	if ((softint_pending & intr_mask) & SI_TO_IRQBIT(si)) {	\
		softint_pending &= ~SI_TO_IRQBIT(si);			\
                __raise(ipl);                                           \
		restore_interrupts(oldirqstate);			\
		softintr_dispatch(si);					\
		oldirqstate = disable_interrupts(I32_bit);		\
		pxa2x0_setipl(spl_save);					\
	}

	do {
		DO_SOFTINT(SI_SOFTSERIAL,IPL_SOFTSERIAL);
		DO_SOFTINT(SI_SOFTNET, IPL_SOFTNET);
		DO_SOFTINT(SI_SOFTCLOCK, IPL_SOFTCLOCK);
		DO_SOFTINT(SI_SOFT, IPL_SOFT);
	} while( softint_pending & intr_mask );
#else
	while( (si = find_first_bit(softint_pending & intr_mask)) >= 0 ){
		softint_pending &= ~SI_TO_IRQBIT(si);
		__raise(si_to_ipl(si));
		restore_interrupts(oldirqstate);
		softintr_dispatch(si);
		oldirqstate = disable_interrupts(I32_bit);
		pxa2x0_setipl(spl_save);
	}
#endif

	__cpu_simple_unlock(&processing);

	restore_interrupts(oldirqstate);
}


#undef splx
void
splx(int ipl)
{
	pxa2x0_splx(ipl);
}

#undef _splraise
int
_splraise(int ipl)
{
	return pxa2x0_splraise(ipl);
}

#undef _spllower
int
_spllower(int ipl)
{
	return pxa2x0_spllower(ipl);
}

#undef _setsoftintr
void
_setsoftintr(int si)
{
	return pxa2x0_setsoftintr(si);
}



/*
 * Initialize interrupt dispatcher.
 */
void
pxa2x0_intr_init(void)
{
	int i;

	for( i=0; i < sizeof handler / sizeof handler[0]; ++i ){
		handler[i].func = stray_interrupt;
		handler[i].cookie = (void *)(i);
		extirq_level[i] = IPL_SERIAL;
	}

	init_interrupt_masks();

	_splraise(IPL_SERIAL);
	enable_interrupts(I32_bit);
}

void
pxa2x0_set_intcbase( vaddr_t addr )
{
	pxaic_base = addr;
}

void *
pxa2x0_intr_establish(int irqno, int level,
		      int (*func)(void *), void *cookie)
{
	int psw;

	if (irqno < PXA2X0_IRQ_MIN || irqno >= ICU_LEN )
		panic("intr_establish: bogus irq number %d", irqno);

	psw = disable_interrupts(I32_bit);

	handler[irqno].cookie = cookie;
	handler[irqno].func = func;
	extirq_level[irqno] = level;
	pxa2x0_update_intr_masks( irqno, level );

	intr_mask = pxa2x0_imask[current_spl_level];
	
	restore_interrupts(psw);

	return ( &handler[irqno] );
}



/*
 * Glue for drivers of sa11x0 compatible integrated logics.
 */
void *
sa11x0_intr_establish(sa11x0_chipset_tag_t ic, int irq, int type, int level,
		      int (*ih_fun)(void *), void *ih_arg)
{
	return pxa2x0_intr_establish(irq,level,ih_fun,ih_arg);
}