Commit 3c10c9c4 authored by Kumar Gala's avatar Kumar Gala Committed by Paul Mackerras

powerpc/mpic: Fix regression caused by change of default IRQ affinity

The Freescale implementation of MPIC only allows a single CPU destination
for non-IPI interrupts.  We add a flag to the mpic_init to distinquish
these variants of MPIC.  We pull in the irq_choose_cpu from sparc64 to
select a single CPU as the destination of the interrupt.

This is to deal with the fact that the default smp affinity was
changed by commit 18404756 ("genirq:
Expose default irq affinity mask (take 3)") to be all CPUs.
Signed-off-by: default avatarKumar Gala <galak@kernel.crashing.org>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent f9226d57
......@@ -355,6 +355,8 @@ struct mpic
#define MPIC_NO_BIAS 0x00000400
/* Ignore NIRQS as reported by FRR */
#define MPIC_BROKEN_FRR_NIRQS 0x00000800
/* Destination only supports a single CPU at a time */
#define MPIC_SINGLE_DEST_CPU 0x00001000
/* MPIC HW modification ID */
#define MPIC_REGSET_MASK 0xf0000000
......
......@@ -78,7 +78,8 @@ void __init mpc85xx_ds_pic_init(void)
mpic = mpic_alloc(np, r.start,
MPIC_PRIMARY | MPIC_WANTS_RESET |
MPIC_BIG_ENDIAN | MPIC_BROKEN_FRR_NIRQS,
MPIC_BIG_ENDIAN | MPIC_BROKEN_FRR_NIRQS |
MPIC_SINGLE_DEST_CPU,
0, 256, " OpenPIC ");
BUG_ON(mpic == NULL);
of_node_put(np);
......
......@@ -44,7 +44,8 @@ void __init mpc86xx_init_irq(void)
mpic = mpic_alloc(np, res.start,
MPIC_PRIMARY | MPIC_WANTS_RESET |
MPIC_BIG_ENDIAN | MPIC_BROKEN_FRR_NIRQS,
MPIC_BIG_ENDIAN | MPIC_BROKEN_FRR_NIRQS |
MPIC_SINGLE_DEST_CPU,
0, 256, " MPIC ");
of_node_put(np);
BUG_ON(mpic == NULL);
......
......@@ -563,6 +563,51 @@ static void __init mpic_scan_ht_pics(struct mpic *mpic)
#endif /* CONFIG_MPIC_U3_HT_IRQS */
#ifdef CONFIG_SMP
static int irq_choose_cpu(unsigned int virt_irq)
{
cpumask_t mask = irq_desc[virt_irq].affinity;
int cpuid;
if (cpus_equal(mask, CPU_MASK_ALL)) {
static int irq_rover;
static DEFINE_SPINLOCK(irq_rover_lock);
unsigned long flags;
/* Round-robin distribution... */
do_round_robin:
spin_lock_irqsave(&irq_rover_lock, flags);
while (!cpu_online(irq_rover)) {
if (++irq_rover >= NR_CPUS)
irq_rover = 0;
}
cpuid = irq_rover;
do {
if (++irq_rover >= NR_CPUS)
irq_rover = 0;
} while (!cpu_online(irq_rover));
spin_unlock_irqrestore(&irq_rover_lock, flags);
} else {
cpumask_t tmp;
cpus_and(tmp, cpu_online_map, mask);
if (cpus_empty(tmp))
goto do_round_robin;
cpuid = first_cpu(tmp);
}
return cpuid;
}
#else
static int irq_choose_cpu(unsigned int virt_irq)
{
return hard_smp_processor_id();
}
#endif
#define mpic_irq_to_hw(virq) ((unsigned int)irq_map[virq].hwirq)
......@@ -777,12 +822,18 @@ void mpic_set_affinity(unsigned int irq, cpumask_t cpumask)
struct mpic *mpic = mpic_from_irq(irq);
unsigned int src = mpic_irq_to_hw(irq);
cpumask_t tmp;
if (mpic->flags & MPIC_SINGLE_DEST_CPU) {
int cpuid = irq_choose_cpu(irq);
cpus_and(tmp, cpumask, cpu_online_map);
mpic_irq_write(src, MPIC_INFO(IRQ_DESTINATION), 1 << cpuid);
} else {
cpumask_t tmp;
mpic_irq_write(src, MPIC_INFO(IRQ_DESTINATION),
mpic_physmask(cpus_addr(tmp)[0]));
cpus_and(tmp, cpumask, cpu_online_map);
mpic_irq_write(src, MPIC_INFO(IRQ_DESTINATION),
mpic_physmask(cpus_addr(tmp)[0]));
}
}
static unsigned int mpic_type_to_vecpri(struct mpic *mpic, unsigned int type)
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment