Merge branch 'upstream'
[linux-2.6] / arch / ia64 / kernel / irq.c
1 /*
2  *      linux/arch/ia64/kernel/irq.c
3  *
4  *      Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
5  *
6  * This file contains the code used by various IRQ handling routines:
7  * asking for different IRQ's should be done through these routines
8  * instead of just grabbing them. Thus setups with different IRQ numbers
9  * shouldn't result in any weird surprises, and installing new handlers
10  * should be easier.
11  *
12  * Copyright (C) Ashok Raj<ashok.raj@intel.com>, Intel Corporation 2004
13  *
14  * 4/14/2004: Added code to handle cpu migration and do safe irq
15  *                      migration without lossing interrupts for iosapic
16  *                      architecture.
17  */
18
19 #include <asm/delay.h>
20 #include <asm/uaccess.h>
21 #include <linux/module.h>
22 #include <linux/seq_file.h>
23 #include <linux/interrupt.h>
24 #include <linux/kernel_stat.h>
25
26 /*
27  * 'what should we do if we get a hw irq event on an illegal vector'.
28  * each architecture has to answer this themselves.
29  */
30 void ack_bad_irq(unsigned int irq)
31 {
32         printk(KERN_ERR "Unexpected irq vector 0x%x on CPU %u!\n", irq, smp_processor_id());
33 }
34
35 #ifdef CONFIG_IA64_GENERIC
36 unsigned int __ia64_local_vector_to_irq (ia64_vector vec)
37 {
38         return (unsigned int) vec;
39 }
40 #endif
41
42 /*
43  * Interrupt statistics:
44  */
45
46 atomic_t irq_err_count;
47
48 /*
49  * /proc/interrupts printing:
50  */
51
52 int show_interrupts(struct seq_file *p, void *v)
53 {
54         int i = *(loff_t *) v, j;
55         struct irqaction * action;
56         unsigned long flags;
57
58         if (i == 0) {
59                 seq_printf(p, "           ");
60                 for_each_online_cpu(j) {
61                         seq_printf(p, "CPU%d       ",j);
62                 }
63                 seq_putc(p, '\n');
64         }
65
66         if (i < NR_IRQS) {
67                 spin_lock_irqsave(&irq_desc[i].lock, flags);
68                 action = irq_desc[i].action;
69                 if (!action)
70                         goto skip;
71                 seq_printf(p, "%3d: ",i);
72 #ifndef CONFIG_SMP
73                 seq_printf(p, "%10u ", kstat_irqs(i));
74 #else
75                 for_each_online_cpu(j) {
76                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
77                 }
78 #endif
79                 seq_printf(p, " %14s", irq_desc[i].handler->typename);
80                 seq_printf(p, "  %s", action->name);
81
82                 for (action=action->next; action; action = action->next)
83                         seq_printf(p, ", %s", action->name);
84
85                 seq_putc(p, '\n');
86 skip:
87                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
88         } else if (i == NR_IRQS)
89                 seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
90         return 0;
91 }
92
93 #ifdef CONFIG_SMP
94 static char irq_redir [NR_IRQS]; // = { [0 ... NR_IRQS-1] = 1 };
95
96 void set_irq_affinity_info (unsigned int irq, int hwid, int redir)
97 {
98         cpumask_t mask = CPU_MASK_NONE;
99
100         cpu_set(cpu_logical_id(hwid), mask);
101
102         if (irq < NR_IRQS) {
103                 irq_affinity[irq] = mask;
104                 set_irq_info(irq, mask);
105                 irq_redir[irq] = (char) (redir & 0xff);
106         }
107 }
108 #endif /* CONFIG_SMP */
109
110 #ifdef CONFIG_HOTPLUG_CPU
111 unsigned int vectors_in_migration[NR_IRQS];
112
113 /*
114  * Since cpu_online_map is already updated, we just need to check for
115  * affinity that has zeros
116  */
117 static void migrate_irqs(void)
118 {
119         cpumask_t       mask;
120         irq_desc_t *desc;
121         int             irq, new_cpu;
122
123         for (irq=0; irq < NR_IRQS; irq++) {
124                 desc = irq_descp(irq);
125
126                 /*
127                  * No handling for now.
128                  * TBD: Implement a disable function so we can now
129                  * tell CPU not to respond to these local intr sources.
130                  * such as ITV,CPEI,MCA etc.
131                  */
132                 if (desc->status == IRQ_PER_CPU)
133                         continue;
134
135                 cpus_and(mask, irq_affinity[irq], cpu_online_map);
136                 if (any_online_cpu(mask) == NR_CPUS) {
137                         /*
138                          * Save it for phase 2 processing
139                          */
140                         vectors_in_migration[irq] = irq;
141
142                         new_cpu = any_online_cpu(cpu_online_map);
143                         mask = cpumask_of_cpu(new_cpu);
144
145                         /*
146                          * Al three are essential, currently WARN_ON.. maybe panic?
147                          */
148                         if (desc->handler && desc->handler->disable &&
149                                 desc->handler->enable && desc->handler->set_affinity) {
150                                 desc->handler->disable(irq);
151                                 desc->handler->set_affinity(irq, mask);
152                                 desc->handler->enable(irq);
153                         } else {
154                                 WARN_ON((!(desc->handler) || !(desc->handler->disable) ||
155                                                 !(desc->handler->enable) ||
156                                                 !(desc->handler->set_affinity)));
157                         }
158                 }
159         }
160 }
161
162 void fixup_irqs(void)
163 {
164         unsigned int irq;
165         extern void ia64_process_pending_intr(void);
166         extern void ia64_disable_timer(void);
167         extern volatile int time_keeper_id;
168
169         ia64_disable_timer();
170
171         /*
172          * Find a new timesync master
173          */
174         if (smp_processor_id() == time_keeper_id) {
175                 time_keeper_id = first_cpu(cpu_online_map);
176                 printk ("CPU %d is now promoted to time-keeper master\n", time_keeper_id);
177         }
178
179         /*
180          * Phase 1: Locate irq's bound to this cpu and
181          * relocate them for cpu removal.
182          */
183         migrate_irqs();
184
185         /*
186          * Phase 2: Perform interrupt processing for all entries reported in
187          * local APIC.
188          */
189         ia64_process_pending_intr();
190
191         /*
192          * Phase 3: Now handle any interrupts not captured in local APIC.
193          * This is to account for cases that device interrupted during the time the
194          * rte was being disabled and re-programmed.
195          */
196         for (irq=0; irq < NR_IRQS; irq++) {
197                 if (vectors_in_migration[irq]) {
198                         vectors_in_migration[irq]=0;
199                         __do_IRQ(irq, NULL);
200                 }
201         }
202
203         /*
204          * Now let processor die. We do irq disable and max_xtp() to
205          * ensure there is no more interrupts routed to this processor.
206          * But the local timer interrupt can have 1 pending which we
207          * take care in timer_interrupt().
208          */
209         max_xtp();
210         local_irq_disable();
211 }
212 #endif