ia64: Use irqd_irq_disabled() instead of desc->status access
[linux-2.6.git] / 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 IRQs 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 losing 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 ia64_vector __ia64_irq_to_vector(int irq)
37 {
38         return irq_cfg[irq].vector;
39 }
40
41 unsigned int __ia64_local_vector_to_irq (ia64_vector vec)
42 {
43         return __get_cpu_var(vector_irq)[vec];
44 }
45 #endif
46
47 /*
48  * Interrupt statistics:
49  */
50
51 atomic_t irq_err_count;
52
53 /*
54  * /proc/interrupts printing:
55  */
56
57 int show_interrupts(struct seq_file *p, void *v)
58 {
59         int i = *(loff_t *) v, j;
60         struct irqaction * action;
61         unsigned long flags;
62
63         if (i == 0) {
64                 char cpuname[16];
65                 seq_printf(p, "     ");
66                 for_each_online_cpu(j) {
67                         snprintf(cpuname, 10, "CPU%d", j);
68                         seq_printf(p, "%10s ", cpuname);
69                 }
70                 seq_putc(p, '\n');
71         }
72
73         if (i < NR_IRQS) {
74                 raw_spin_lock_irqsave(&irq_desc[i].lock, flags);
75                 action = irq_desc[i].action;
76                 if (!action)
77                         goto skip;
78                 seq_printf(p, "%3d: ",i);
79 #ifndef CONFIG_SMP
80                 seq_printf(p, "%10u ", kstat_irqs(i));
81 #else
82                 for_each_online_cpu(j) {
83                         seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
84                 }
85 #endif
86                 seq_printf(p, " %14s", irq_desc[i].chip->name);
87                 seq_printf(p, "  %s", action->name);
88
89                 for (action=action->next; action; action = action->next)
90                         seq_printf(p, ", %s", action->name);
91
92                 seq_putc(p, '\n');
93 skip:
94                 raw_spin_unlock_irqrestore(&irq_desc[i].lock, flags);
95         } else if (i == NR_IRQS)
96                 seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
97         return 0;
98 }
99
100 #ifdef CONFIG_SMP
101 static char irq_redir [NR_IRQS]; // = { [0 ... NR_IRQS-1] = 1 };
102
103 void set_irq_affinity_info (unsigned int irq, int hwid, int redir)
104 {
105         if (irq < NR_IRQS) {
106                 cpumask_copy(irq_get_irq_data(irq)->affinity,
107                              cpumask_of(cpu_logical_id(hwid)));
108                 irq_redir[irq] = (char) (redir & 0xff);
109         }
110 }
111
112 bool is_affinity_mask_valid(const struct cpumask *cpumask)
113 {
114         if (ia64_platform_is("sn2")) {
115                 /* Only allow one CPU to be specified in the smp_affinity mask */
116                 if (cpumask_weight(cpumask) != 1)
117                         return false;
118         }
119         return true;
120 }
121
122 #endif /* CONFIG_SMP */
123
124 #ifdef CONFIG_HOTPLUG_CPU
125 unsigned int vectors_in_migration[NR_IRQS];
126
127 /*
128  * Since cpu_online_mask is already updated, we just need to check for
129  * affinity that has zeros
130  */
131 static void migrate_irqs(void)
132 {
133         int             irq, new_cpu;
134
135         for (irq=0; irq < NR_IRQS; irq++) {
136                 struct irq_desc *desc = irq_to_desc(irq);
137                 struct irq_data *data = irq_desc_get_irq_data(desc);
138                 struct irq_chip *chip = irq_data_get_irq_chip(data);
139
140                 if (irqd_irq_disabled(data))
141                         continue;
142
143                 /*
144                  * No handling for now.
145                  * TBD: Implement a disable function so we can now
146                  * tell CPU not to respond to these local intr sources.
147                  * such as ITV,CPEI,MCA etc.
148                  */
149                 if (irqd_is_per_cpu(data))
150                         continue;
151
152                 if (cpumask_any_and(data->affinity, cpu_online_mask)
153                     >= nr_cpu_ids) {
154                         /*
155                          * Save it for phase 2 processing
156                          */
157                         vectors_in_migration[irq] = irq;
158
159                         new_cpu = cpumask_any(cpu_online_mask);
160
161                         /*
162                          * Al three are essential, currently WARN_ON.. maybe panic?
163                          */
164                         if (chip && chip->irq_disable &&
165                                 chip->irq_enable && chip->irq_set_affinity) {
166                                 chip->irq_disable(data);
167                                 chip->irq_set_affinity(data,
168                                                        cpumask_of(new_cpu), false);
169                                 chip->irq_enable(data);
170                         } else {
171                                 WARN_ON((!chip || !chip->irq_disable ||
172                                          !chip->irq_enable ||
173                                          !chip->irq_set_affinity));
174                         }
175                 }
176         }
177 }
178
179 void fixup_irqs(void)
180 {
181         unsigned int irq;
182         extern void ia64_process_pending_intr(void);
183         extern volatile int time_keeper_id;
184
185         /* Mask ITV to disable timer */
186         ia64_set_itv(1 << 16);
187
188         /*
189          * Find a new timesync master
190          */
191         if (smp_processor_id() == time_keeper_id) {
192                 time_keeper_id = cpumask_first(cpu_online_mask);
193                 printk ("CPU %d is now promoted to time-keeper master\n", time_keeper_id);
194         }
195
196         /*
197          * Phase 1: Locate IRQs bound to this cpu and
198          * relocate them for cpu removal.
199          */
200         migrate_irqs();
201
202         /*
203          * Phase 2: Perform interrupt processing for all entries reported in
204          * local APIC.
205          */
206         ia64_process_pending_intr();
207
208         /*
209          * Phase 3: Now handle any interrupts not captured in local APIC.
210          * This is to account for cases that device interrupted during the time the
211          * rte was being disabled and re-programmed.
212          */
213         for (irq=0; irq < NR_IRQS; irq++) {
214                 if (vectors_in_migration[irq]) {
215                         struct pt_regs *old_regs = set_irq_regs(NULL);
216
217                         vectors_in_migration[irq]=0;
218                         generic_handle_irq(irq);
219                         set_irq_regs(old_regs);
220                 }
221         }
222
223         /*
224          * Now let processor die. We do irq disable and max_xtp() to
225          * ensure there is no more interrupts routed to this processor.
226          * But the local timer interrupt can have 1 pending which we
227          * take care in timer_interrupt().
228          */
229         max_xtp();
230         local_irq_disable();
231 }
232 #endif