Automatic merge of rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[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 (j=0; j<NR_CPUS; j++)
61                         if (cpu_online(j))
62                                 seq_printf(p, "CPU%d       ",j);
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 (j = 0; j < NR_CPUS; j++)
76                         if (cpu_online(j))
77                                 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
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 /*
95  * This is updated when the user sets irq affinity via /proc
96  */
97 static cpumask_t __cacheline_aligned pending_irq_cpumask[NR_IRQS];
98 static unsigned long pending_irq_redir[BITS_TO_LONGS(NR_IRQS)];
99
100 static char irq_redir [NR_IRQS]; // = { [0 ... NR_IRQS-1] = 1 };
101
102 /*
103  * Arch specific routine for deferred write to iosapic rte to reprogram
104  * intr destination.
105  */
106 void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val)
107 {
108         pending_irq_cpumask[irq] = mask_val;
109 }
110
111 void set_irq_affinity_info (unsigned int irq, int hwid, int redir)
112 {
113         cpumask_t mask = CPU_MASK_NONE;
114
115         cpu_set(cpu_logical_id(hwid), mask);
116
117         if (irq < NR_IRQS) {
118                 irq_affinity[irq] = mask;
119                 irq_redir[irq] = (char) (redir & 0xff);
120         }
121 }
122
123
124 void move_irq(int irq)
125 {
126         /* note - we hold desc->lock */
127         cpumask_t tmp;
128         irq_desc_t *desc = irq_descp(irq);
129         int redir = test_bit(irq, pending_irq_redir);
130
131         if (unlikely(!desc->handler->set_affinity))
132                 return;
133
134         if (!cpus_empty(pending_irq_cpumask[irq])) {
135                 cpus_and(tmp, pending_irq_cpumask[irq], cpu_online_map);
136                 if (unlikely(!cpus_empty(tmp))) {
137                         desc->handler->set_affinity(irq | (redir ? IA64_IRQ_REDIRECTED : 0),
138                                                     pending_irq_cpumask[irq]);
139                 }
140                 cpus_clear(pending_irq_cpumask[irq]);
141         }
142 }
143
144
145 #endif /* CONFIG_SMP */
146
147 #ifdef CONFIG_HOTPLUG_CPU
148 unsigned int vectors_in_migration[NR_IRQS];
149
150 /*
151  * Since cpu_online_map is already updated, we just need to check for
152  * affinity that has zeros
153  */
154 static void migrate_irqs(void)
155 {
156         cpumask_t       mask;
157         irq_desc_t *desc;
158         int             irq, new_cpu;
159
160         for (irq=0; irq < NR_IRQS; irq++) {
161                 desc = irq_descp(irq);
162
163                 /*
164                  * No handling for now.
165                  * TBD: Implement a disable function so we can now
166                  * tell CPU not to respond to these local intr sources.
167                  * such as ITV,CPEI,MCA etc.
168                  */
169                 if (desc->status == IRQ_PER_CPU)
170                         continue;
171
172                 cpus_and(mask, irq_affinity[irq], cpu_online_map);
173                 if (any_online_cpu(mask) == NR_CPUS) {
174                         /*
175                          * Save it for phase 2 processing
176                          */
177                         vectors_in_migration[irq] = irq;
178
179                         new_cpu = any_online_cpu(cpu_online_map);
180                         mask = cpumask_of_cpu(new_cpu);
181
182                         /*
183                          * Al three are essential, currently WARN_ON.. maybe panic?
184                          */
185                         if (desc->handler && desc->handler->disable &&
186                                 desc->handler->enable && desc->handler->set_affinity) {
187                                 desc->handler->disable(irq);
188                                 desc->handler->set_affinity(irq, mask);
189                                 desc->handler->enable(irq);
190                         } else {
191                                 WARN_ON((!(desc->handler) || !(desc->handler->disable) ||
192                                                 !(desc->handler->enable) ||
193                                                 !(desc->handler->set_affinity)));
194                         }
195                 }
196         }
197 }
198
199 void fixup_irqs(void)
200 {
201         unsigned int irq;
202         extern void ia64_process_pending_intr(void);
203
204         ia64_set_itv(1<<16);
205         /*
206          * Phase 1: Locate irq's bound to this cpu and
207          * relocate them for cpu removal.
208          */
209         migrate_irqs();
210
211         /*
212          * Phase 2: Perform interrupt processing for all entries reported in
213          * local APIC.
214          */
215         ia64_process_pending_intr();
216
217         /*
218          * Phase 3: Now handle any interrupts not captured in local APIC.
219          * This is to account for cases that device interrupted during the time the
220          * rte was being disabled and re-programmed.
221          */
222         for (irq=0; irq < NR_IRQS; irq++) {
223                 if (vectors_in_migration[irq]) {
224                         vectors_in_migration[irq]=0;
225                         __do_IRQ(irq, NULL);
226                 }
227         }
228
229         /*
230          * Now let processor die. We do irq disable and max_xtp() to
231          * ensure there is no more interrupts routed to this processor.
232          * But the local timer interrupt can have 1 pending which we
233          * take care in timer_interrupt().
234          */
235         max_xtp();
236         local_irq_disable();
237 }
238 #endif