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 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].chip->name); 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_desc[irq].affinity = mask; 104 irq_redir[irq] = (char) (redir & 0xff); 105 } 106 } 107 108 bool is_affinity_mask_valid(cpumask_t cpumask) 109 { 110 if (ia64_platform_is("sn2")) { 111 /* Only allow one CPU to be specified in the smp_affinity mask */ 112 if (cpus_weight(cpumask) != 1) 113 return false; 114 } 115 return true; 116 } 117 118 #endif /* CONFIG_SMP */ 119 120 #ifdef CONFIG_HOTPLUG_CPU 121 unsigned int vectors_in_migration[NR_IRQS]; 122 123 /* 124 * Since cpu_online_map is already updated, we just need to check for 125 * affinity that has zeros 126 */ 127 static void migrate_irqs(void) 128 { 129 cpumask_t mask; 130 irq_desc_t *desc; 131 int irq, new_cpu; 132 133 for (irq=0; irq < NR_IRQS; irq++) { 134 desc = irq_desc + irq; 135 136 if (desc->status == IRQ_DISABLED) 137 continue; 138 139 /* 140 * No handling for now. 141 * TBD: Implement a disable function so we can now 142 * tell CPU not to respond to these local intr sources. 143 * such as ITV,CPEI,MCA etc. 144 */ 145 if (desc->status == IRQ_PER_CPU) 146 continue; 147 148 cpus_and(mask, irq_desc[irq].affinity, cpu_online_map); 149 if (any_online_cpu(mask) == NR_CPUS) { 150 /* 151 * Save it for phase 2 processing 152 */ 153 vectors_in_migration[irq] = irq; 154 155 new_cpu = any_online_cpu(cpu_online_map); 156 mask = cpumask_of_cpu(new_cpu); 157 158 /* 159 * Al three are essential, currently WARN_ON.. maybe panic? 160 */ 161 if (desc->chip && desc->chip->disable && 162 desc->chip->enable && desc->chip->set_affinity) { 163 desc->chip->disable(irq); 164 desc->chip->set_affinity(irq, mask); 165 desc->chip->enable(irq); 166 } else { 167 WARN_ON((!(desc->chip) || !(desc->chip->disable) || 168 !(desc->chip->enable) || 169 !(desc->chip->set_affinity))); 170 } 171 } 172 } 173 } 174 175 void fixup_irqs(void) 176 { 177 unsigned int irq; 178 extern void ia64_process_pending_intr(void); 179 extern void ia64_disable_timer(void); 180 extern volatile int time_keeper_id; 181 182 ia64_disable_timer(); 183 184 /* 185 * Find a new timesync master 186 */ 187 if (smp_processor_id() == time_keeper_id) { 188 time_keeper_id = first_cpu(cpu_online_map); 189 printk ("CPU %d is now promoted to time-keeper master\n", time_keeper_id); 190 } 191 192 /* 193 * Phase 1: Locate IRQs bound to this cpu and 194 * relocate them for cpu removal. 195 */ 196 migrate_irqs(); 197 198 /* 199 * Phase 2: Perform interrupt processing for all entries reported in 200 * local APIC. 201 */ 202 ia64_process_pending_intr(); 203 204 /* 205 * Phase 3: Now handle any interrupts not captured in local APIC. 206 * This is to account for cases that device interrupted during the time the 207 * rte was being disabled and re-programmed. 208 */ 209 for (irq=0; irq < NR_IRQS; irq++) { 210 if (vectors_in_migration[irq]) { 211 struct pt_regs *old_regs = set_irq_regs(NULL); 212 213 vectors_in_migration[irq]=0; 214 generic_handle_irq(irq); 215 set_irq_regs(old_regs); 216 } 217 } 218 219 /* 220 * Now let processor die. We do irq disable and max_xtp() to 221 * ensure there is no more interrupts routed to this processor. 222 * But the local timer interrupt can have 1 pending which we 223 * take care in timer_interrupt(). 224 */ 225 max_xtp(); 226 local_irq_disable(); 227 } 228 #endif 229