diff options
Diffstat (limited to 'arch/ia64/kernel/irq_ia64.c')
| -rw-r--r-- | arch/ia64/kernel/irq_ia64.c | 201 |
1 files changed, 166 insertions, 35 deletions
diff --git a/arch/ia64/kernel/irq_ia64.c b/arch/ia64/kernel/irq_ia64.c index bc47049f060f..072427c2c3f6 100644 --- a/arch/ia64/kernel/irq_ia64.c +++ b/arch/ia64/kernel/irq_ia64.c @@ -46,6 +46,12 @@ #define IRQ_DEBUG 0 +#define IRQ_VECTOR_UNASSIGNED (0) + +#define IRQ_UNUSED (0) +#define IRQ_USED (1) +#define IRQ_RSVD (2) + /* These can be overridden in platform_irq_init */ int ia64_first_device_vector = IA64_DEF_FIRST_DEVICE_VECTOR; int ia64_last_device_vector = IA64_DEF_LAST_DEVICE_VECTOR; @@ -64,46 +70,161 @@ __u8 isa_irq_to_vector_map[16] = { }; EXPORT_SYMBOL(isa_irq_to_vector_map); -static unsigned long ia64_vector_mask[BITS_TO_LONGS(IA64_MAX_DEVICE_VECTORS)]; +DEFINE_SPINLOCK(vector_lock); + +struct irq_cfg irq_cfg[NR_IRQS] __read_mostly = { + [0 ... NR_IRQS - 1] = { .vector = IRQ_VECTOR_UNASSIGNED } +}; + +DEFINE_PER_CPU(int[IA64_NUM_VECTORS], vector_irq) = { + [0 ... IA64_NUM_VECTORS - 1] = IA64_SPURIOUS_INT_VECTOR +}; + +static int irq_status[NR_IRQS] = { + [0 ... NR_IRQS -1] = IRQ_UNUSED +}; + +int check_irq_used(int irq) +{ + if (irq_status[irq] == IRQ_USED) + return 1; + + return -1; +} + +static void reserve_irq(unsigned int irq) +{ + unsigned long flags; + + spin_lock_irqsave(&vector_lock, flags); + irq_status[irq] = IRQ_RSVD; + spin_unlock_irqrestore(&vector_lock, flags); +} + +static inline int find_unassigned_irq(void) +{ + int irq; + + for (irq = IA64_FIRST_DEVICE_VECTOR; irq < NR_IRQS; irq++) + if (irq_status[irq] == IRQ_UNUSED) + return irq; + return -ENOSPC; +} + +static inline int find_unassigned_vector(void) +{ + int vector; + + for (vector = IA64_FIRST_DEVICE_VECTOR; + vector <= IA64_LAST_DEVICE_VECTOR; vector++) + if (__get_cpu_var(vector_irq[vector]) == IA64_SPURIOUS_INT_VECTOR) + return vector; + return -ENOSPC; +} + +static int __bind_irq_vector(int irq, int vector) +{ + int cpu; + + if (irq_to_vector(irq) == vector) + return 0; + if (irq_to_vector(irq) != IRQ_VECTOR_UNASSIGNED) + return -EBUSY; + for_each_online_cpu(cpu) + per_cpu(vector_irq, cpu)[vector] = irq; + irq_cfg[irq].vector = vector; + irq_status[irq] = IRQ_USED; + return 0; +} + +int bind_irq_vector(int irq, int vector) +{ + unsigned long flags; + int ret; + + spin_lock_irqsave(&vector_lock, flags); + ret = __bind_irq_vector(irq, vector); + spin_unlock_irqrestore(&vector_lock, flags); + return ret; +} + +static void clear_irq_vector(int irq) +{ + unsigned long flags; + int vector, cpu; + + spin_lock_irqsave(&vector_lock, flags); + BUG_ON((unsigned)irq >= NR_IRQS); + BUG_ON(irq_cfg[irq].vector == IRQ_VECTOR_UNASSIGNED); + vector = irq_cfg[irq].vector; + for_each_online_cpu(cpu) + per_cpu(vector_irq, cpu)[vector] = IA64_SPURIOUS_INT_VECTOR; + irq_cfg[irq].vector = IRQ_VECTOR_UNASSIGNED; + irq_status[irq] = IRQ_UNUSED; + spin_unlock_irqrestore(&vector_lock, flags); +} int assign_irq_vector (int irq) { - int pos, vector; - again: - pos = find_first_zero_bit(ia64_vector_mask, IA64_NUM_DEVICE_VECTORS); - vector = IA64_FIRST_DEVICE_VECTOR + pos; - if (vector > IA64_LAST_DEVICE_VECTOR) - return -ENOSPC; - if (test_and_set_bit(pos, ia64_vector_mask)) - goto again; + unsigned long flags; + int vector = -ENOSPC; + + if (irq < 0) { + goto out; + } + spin_lock_irqsave(&vector_lock, flags); + vector = find_unassigned_vector(); + if (vector < 0) + goto out; + BUG_ON(__bind_irq_vector(irq, vector)); + spin_unlock_irqrestore(&vector_lock, flags); + out: return vector; } void free_irq_vector (int vector) { - int pos; - - if (vector < IA64_FIRST_DEVICE_VECTOR || vector > IA64_LAST_DEVICE_VECTOR) + if (vector < IA64_FIRST_DEVICE_VECTOR || + vector > IA64_LAST_DEVICE_VECTOR) return; - - pos = vector - IA64_FIRST_DEVICE_VECTOR; - if (!test_and_clear_bit(pos, ia64_vector_mask)) - printk(KERN_WARNING "%s: double free!\n", __FUNCTION__); + clear_irq_vector(vector); } int reserve_irq_vector (int vector) { - int pos; - if (vector < IA64_FIRST_DEVICE_VECTOR || vector > IA64_LAST_DEVICE_VECTOR) return -EINVAL; + return !!bind_irq_vector(vector, vector); +} - pos = vector - IA64_FIRST_DEVICE_VECTOR; - return test_and_set_bit(pos, ia64_vector_mask); +/* + * Initialize vector_irq on a new cpu. This function must be called + * with vector_lock held. + */ +void __setup_vector_irq(int cpu) +{ + int irq, vector; + + /* Clear vector_irq */ + for (vector = 0; vector < IA64_NUM_VECTORS; ++vector) + per_cpu(vector_irq, cpu)[vector] = IA64_SPURIOUS_INT_VECTOR; + /* Mark the inuse vectors */ + for (irq = 0; irq < NR_IRQS; ++irq) { + if ((vector = irq_to_vector(irq)) != IRQ_VECTOR_UNASSIGNED) + per_cpu(vector_irq, cpu)[vector] = irq; + } +} + +void destroy_and_reserve_irq(unsigned int irq) +{ + dynamic_irq_cleanup(irq); + + clear_irq_vector(irq); + reserve_irq(irq); } /* @@ -111,18 +232,29 @@ reserve_irq_vector (int vector) */ int create_irq(void) { - int vector = assign_irq_vector(AUTO_ASSIGN); - - if (vector >= 0) - dynamic_irq_init(vector); - - return vector; + unsigned long flags; + int irq, vector; + + irq = -ENOSPC; + spin_lock_irqsave(&vector_lock, flags); + vector = find_unassigned_vector(); + if (vector < 0) + goto out; + irq = find_unassigned_irq(); + if (irq < 0) + goto out; + BUG_ON(__bind_irq_vector(irq, vector)); + out: + spin_unlock_irqrestore(&vector_lock, flags); + if (irq >= 0) + dynamic_irq_init(irq); + return irq; } void destroy_irq(unsigned int irq) { dynamic_irq_cleanup(irq); - free_irq_vector(irq); + clear_irq_vector(irq); } #ifdef CONFIG_SMP @@ -301,14 +433,13 @@ register_percpu_irq (ia64_vector vec, struct irqaction *action) irq_desc_t *desc; unsigned int irq; - for (irq = 0; irq < NR_IRQS; ++irq) - if (irq_to_vector(irq) == vec) { - desc = irq_desc + irq; - desc->status |= IRQ_PER_CPU; - desc->chip = &irq_type_ia64_lsapic; - if (action) - setup_irq(irq, action); - } + irq = vec; + BUG_ON(bind_irq_vector(irq, vec)); + desc = irq_desc + irq; + desc->status |= IRQ_PER_CPU; + desc->chip = &irq_type_ia64_lsapic; + if (action) + setup_irq(irq, action); } void __init |
