ia64: Use generic show_interrupts()
[linux-3.10.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 int arch_show_interrupts(struct seq_file *p, int prec)
57 {
58         seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
59         return 0;
60 }
61
62 #ifdef CONFIG_SMP
63 static char irq_redir [NR_IRQS]; // = { [0 ... NR_IRQS-1] = 1 };
64
65 void set_irq_affinity_info (unsigned int irq, int hwid, int redir)
66 {
67         if (irq < NR_IRQS) {
68                 cpumask_copy(irq_get_irq_data(irq)->affinity,
69                              cpumask_of(cpu_logical_id(hwid)));
70                 irq_redir[irq] = (char) (redir & 0xff);
71         }
72 }
73
74 bool is_affinity_mask_valid(const struct cpumask *cpumask)
75 {
76         if (ia64_platform_is("sn2")) {
77                 /* Only allow one CPU to be specified in the smp_affinity mask */
78                 if (cpumask_weight(cpumask) != 1)
79                         return false;
80         }
81         return true;
82 }
83
84 #endif /* CONFIG_SMP */
85
86 #ifdef CONFIG_HOTPLUG_CPU
87 unsigned int vectors_in_migration[NR_IRQS];
88
89 /*
90  * Since cpu_online_mask is already updated, we just need to check for
91  * affinity that has zeros
92  */
93 static void migrate_irqs(void)
94 {
95         int             irq, new_cpu;
96
97         for (irq=0; irq < NR_IRQS; irq++) {
98                 struct irq_desc *desc = irq_to_desc(irq);
99                 struct irq_data *data = irq_desc_get_irq_data(desc);
100                 struct irq_chip *chip = irq_data_get_irq_chip(data);
101
102                 if (irqd_irq_disabled(data))
103                         continue;
104
105                 /*
106                  * No handling for now.
107                  * TBD: Implement a disable function so we can now
108                  * tell CPU not to respond to these local intr sources.
109                  * such as ITV,CPEI,MCA etc.
110                  */
111                 if (irqd_is_per_cpu(data))
112                         continue;
113
114                 if (cpumask_any_and(data->affinity, cpu_online_mask)
115                     >= nr_cpu_ids) {
116                         /*
117                          * Save it for phase 2 processing
118                          */
119                         vectors_in_migration[irq] = irq;
120
121                         new_cpu = cpumask_any(cpu_online_mask);
122
123                         /*
124                          * Al three are essential, currently WARN_ON.. maybe panic?
125                          */
126                         if (chip && chip->irq_disable &&
127                                 chip->irq_enable && chip->irq_set_affinity) {
128                                 chip->irq_disable(data);
129                                 chip->irq_set_affinity(data,
130                                                        cpumask_of(new_cpu), false);
131                                 chip->irq_enable(data);
132                         } else {
133                                 WARN_ON((!chip || !chip->irq_disable ||
134                                          !chip->irq_enable ||
135                                          !chip->irq_set_affinity));
136                         }
137                 }
138         }
139 }
140
141 void fixup_irqs(void)
142 {
143         unsigned int irq;
144         extern void ia64_process_pending_intr(void);
145         extern volatile int time_keeper_id;
146
147         /* Mask ITV to disable timer */
148         ia64_set_itv(1 << 16);
149
150         /*
151          * Find a new timesync master
152          */
153         if (smp_processor_id() == time_keeper_id) {
154                 time_keeper_id = cpumask_first(cpu_online_mask);
155                 printk ("CPU %d is now promoted to time-keeper master\n", time_keeper_id);
156         }
157
158         /*
159          * Phase 1: Locate IRQs bound to this cpu and
160          * relocate them for cpu removal.
161          */
162         migrate_irqs();
163
164         /*
165          * Phase 2: Perform interrupt processing for all entries reported in
166          * local APIC.
167          */
168         ia64_process_pending_intr();
169
170         /*
171          * Phase 3: Now handle any interrupts not captured in local APIC.
172          * This is to account for cases that device interrupted during the time the
173          * rte was being disabled and re-programmed.
174          */
175         for (irq=0; irq < NR_IRQS; irq++) {
176                 if (vectors_in_migration[irq]) {
177                         struct pt_regs *old_regs = set_irq_regs(NULL);
178
179                         vectors_in_migration[irq]=0;
180                         generic_handle_irq(irq);
181                         set_irq_regs(old_regs);
182                 }
183         }
184
185         /*
186          * Now let processor die. We do irq disable and max_xtp() to
187          * ensure there is no more interrupts routed to this processor.
188          * But the local timer interrupt can have 1 pending which we
189          * take care in timer_interrupt().
190          */
191         max_xtp();
192         local_irq_disable();
193 }
194 #endif