Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a825e9a7 authored by Finn Thain's avatar Finn Thain Committed by Greg Kroah-Hartman
Browse files

m68k: Call timer_interrupt() with interrupts disabled 



[ Upstream commit 1efdd4bd254311498123a15fa0acd565f454da97 ]

Some platforms execute their timer handler with the interrupt priority
level set below 6. That means the handler could be interrupted by another
driver and this could lead to re-entry of the timer core.

Avoid this by use of local_irq_save/restore for timer interrupt dispatch.
This provides mutual exclusion around the timer interrupt flag access
which is needed later in this series for the clocksource conversion.

Reported-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/alpine.DEB.2.21.1811131407120.2697@nanos.tec.linutronix.de


Signed-off-by: default avatarFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
parent 283163a3

arch/m68k/amiga/cia.c

+9 −0
Original line number Diff line number Diff line
@@ -88,10 +88,19 @@ static irqreturn_t cia_handler(int irq, void *dev_id) 
	struct ciabase *base = dev_id;

	int mach_irq;

	unsigned char ints;

	unsigned long flags;



	/* Interrupts get disabled while the timer irq flag is cleared and

	 * the timer interrupt serviced.

	 */

	mach_irq = base->cia_irq;

	local_irq_save(flags);

	ints = cia_set_irq(base, CIA_ICR_ALL);

	amiga_custom.intreq = base->int_mask;

	if (ints & 1)

		generic_handle_irq(mach_irq);

	local_irq_restore(flags);

	mach_irq++, ints >>= 1;

	for (; ints; mach_irq++, ints >>= 1) {

		if (ints & 1)

			generic_handle_irq(mach_irq);

arch/m68k/atari/ataints.c

+2 −2
Original line number Diff line number Diff line
@@ -142,7 +142,7 @@ struct mfptimerbase { 
	.name		= "MFP Timer D"

};



static irqreturn_t mfptimer_handler(int irq, void *dev_id)

static irqreturn_t mfp_timer_d_handler(int irq, void *dev_id)

{

	struct mfptimerbase *base = dev_id;

	int mach_irq;
@@ -344,7 +344,7 @@ void __init atari_init_IRQ(void) 
	st_mfp.tim_ct_cd = (st_mfp.tim_ct_cd & 0xf0) | 0x6;



	/* request timer D dispatch handler */

	if (request_irq(IRQ_MFP_TIMD, mfptimer_handler, IRQF_SHARED,

	if (request_irq(IRQ_MFP_TIMD, mfp_timer_d_handler, IRQF_SHARED,

			stmfp_base.name, &stmfp_base))

		pr_err("Couldn't register %s interrupt\n", stmfp_base.name);

arch/m68k/atari/time.c

+14 −1
Original line number Diff line number Diff line
@@ -24,6 +24,18 @@ 
DEFINE_SPINLOCK(rtc_lock);

EXPORT_SYMBOL_GPL(rtc_lock);



static irqreturn_t mfp_timer_c_handler(int irq, void *dev_id)

{

	irq_handler_t timer_routine = dev_id;

	unsigned long flags;



	local_irq_save(flags);

	timer_routine(0, NULL);

	local_irq_restore(flags);



	return IRQ_HANDLED;

}



void __init

atari_sched_init(irq_handler_t timer_routine)

{
@@ -32,7 +44,8 @@ atari_sched_init(irq_handler_t timer_routine) 
    /* start timer C, div = 1:100 */

    st_mfp.tim_ct_cd = (st_mfp.tim_ct_cd & 15) | 0x60;

    /* install interrupt service routine for MFP Timer C */

    if (request_irq(IRQ_MFP_TIMC, timer_routine, 0, "timer", timer_routine))

    if (request_irq(IRQ_MFP_TIMC, mfp_timer_c_handler, 0, "timer",

                    timer_routine))

	pr_err("Couldn't register timer interrupt\n");

}

arch/m68k/bvme6000/config.c

+10 −10
Original line number Diff line number Diff line
@@ -44,11 +44,6 @@ extern int bvme6000_hwclk (int, struct rtc_time *); 
extern void bvme6000_reset (void);

void bvme6000_set_vectors (void);



/* Save tick handler routine pointer, will point to xtime_update() in

 * kernel/timer/timekeeping.c, called via bvme6000_process_int() */



static irq_handler_t tick_handler;





int __init bvme6000_parse_bootinfo(const struct bi_record *bi)

{
@@ -157,12 +152,18 @@ irqreturn_t bvme6000_abort_int (int irq, void *dev_id) 


static irqreturn_t bvme6000_timer_int (int irq, void *dev_id)

{

    irq_handler_t timer_routine = dev_id;

    unsigned long flags;

    volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;

    unsigned char msr = rtc->msr & 0xc0;

    unsigned char msr;



    local_irq_save(flags);

    msr = rtc->msr & 0xc0;

    rtc->msr = msr | 0x20;		/* Ack the interrupt */

    timer_routine(0, NULL);

    local_irq_restore(flags);



    return tick_handler(irq, dev_id);

    return IRQ_HANDLED;

}



/*
@@ -181,9 +182,8 @@ void bvme6000_sched_init (irq_handler_t timer_routine) 


    rtc->msr = 0;	/* Ensure timer registers accessible */



    tick_handler = timer_routine;

    if (request_irq(BVME_IRQ_RTC, bvme6000_timer_int, 0,

				"timer", bvme6000_timer_int))

    if (request_irq(BVME_IRQ_RTC, bvme6000_timer_int, 0, "timer",

                    timer_routine))

	panic ("Couldn't register timer int");



    rtc->t1cr_omr = 0x04;	/* Mode 2, ext clk */

arch/m68k/hp300/time.c

+8 −2
Original line number Diff line number Diff line
@@ -38,13 +38,19 @@ 


static irqreturn_t hp300_tick(int irq, void *dev_id)

{

	irq_handler_t timer_routine = dev_id;

	unsigned long flags;

	unsigned long tmp;

	irq_handler_t vector = dev_id;



	local_irq_save(flags);

	in_8(CLOCKBASE + CLKSR);

	asm volatile ("movpw %1@(5),%0" : "=d" (tmp) : "a" (CLOCKBASE));

	timer_routine(0, NULL);

	local_irq_restore(flags);



	/* Turn off the network and SCSI leds */

	blinken_leds(0, 0xe0);

	return vector(irq, NULL);

	return IRQ_HANDLED;

}



u32 hp300_gettimeoffset(void)