2 * Derived from arch/i386/kernel/irq.c
3 * Copyright (C) 1992 Linus Torvalds
4 * Adapted from arch/i386 by Gary Thomas
5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 * Updated and modified by Cort Dougan <cort@fsmlabs.com>
7 * Copyright (C) 1996-2001 Cort Dougan
8 * Adapted for Power Macintosh by Paul Mackerras
9 * Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
10 * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
17 * This file contains the code used by various IRQ handling routines:
18 * asking for different IRQ's should be done through these routines
19 * instead of just grabbing them. Thus setups with different IRQ numbers
20 * shouldn't result in any weird surprises, and installing new handlers
23 * The MPC8xx has an interrupt mask in the SIU. If a bit is set, the
24 * interrupt is _enabled_. As expected, IRQ0 is bit 0 in the 32-bit
25 * mask register (of which only 16 are defined), hence the weird shifting
26 * and complement of the cached_irq_mask. I want to be able to stuff
27 * this right into the SIU SMASK register.
28 * Many of the prep/chrp functions are conditional compiled on CONFIG_8xx
29 * to reduce code space and undefined function references.
32 #include <linux/module.h>
33 #include <linux/threads.h>
34 #include <linux/kernel_stat.h>
35 #include <linux/signal.h>
36 #include <linux/sched.h>
37 #include <linux/ptrace.h>
38 #include <linux/ioport.h>
39 #include <linux/interrupt.h>
40 #include <linux/timex.h>
41 #include <linux/init.h>
42 #include <linux/slab.h>
43 #include <linux/delay.h>
44 #include <linux/irq.h>
45 #include <linux/seq_file.h>
46 #include <linux/cpumask.h>
47 #include <linux/profile.h>
48 #include <linux/bitops.h>
49 #include <linux/pci.h>
51 #include <asm/uaccess.h>
52 #include <asm/system.h>
54 #include <asm/pgtable.h>
56 #include <asm/cache.h>
58 #include <asm/ptrace.h>
59 #include <asm/machdep.h>
60 #ifdef CONFIG_PPC_ISERIES
64 int __irq_offset_value;
65 static int ppc_spurious_interrupts;
68 EXPORT_SYMBOL(__irq_offset_value);
69 atomic_t ppc_n_lost_interrupts;
71 #ifndef CONFIG_PPC_MERGE
72 #define NR_MASK_WORDS ((NR_IRQS + 31) / 32)
73 unsigned long ppc_cached_irq_mask[NR_MASK_WORDS];
77 extern int tau_initialized;
78 extern int tau_interrupts(int);
80 #endif /* CONFIG_PPC32 */
82 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
83 extern atomic_t ipi_recv;
84 extern atomic_t ipi_sent;
88 EXPORT_SYMBOL(irq_desc);
90 int distribute_irqs = 1;
91 u64 ppc64_interrupt_controller;
92 #endif /* CONFIG_PPC64 */
94 int show_interrupts(struct seq_file *p, void *v)
96 int i = *(loff_t *)v, j;
97 struct irqaction *action;
103 for_each_online_cpu(j)
104 seq_printf(p, "CPU%d ", j);
109 desc = get_irq_desc(i);
110 spin_lock_irqsave(&desc->lock, flags);
111 action = desc->action;
112 if (!action || !action->handler)
114 seq_printf(p, "%3d: ", i);
116 for_each_online_cpu(j)
117 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
119 seq_printf(p, "%10u ", kstat_irqs(i));
120 #endif /* CONFIG_SMP */
122 seq_printf(p, " %s ", desc->chip->typename);
124 seq_puts(p, " None ");
125 seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge ");
126 seq_printf(p, " %s", action->name);
127 for (action = action->next; action; action = action->next)
128 seq_printf(p, ", %s", action->name);
131 spin_unlock_irqrestore(&desc->lock, flags);
132 } else if (i == NR_IRQS) {
134 #ifdef CONFIG_TAU_INT
135 if (tau_initialized){
136 seq_puts(p, "TAU: ");
137 for_each_online_cpu(j)
138 seq_printf(p, "%10u ", tau_interrupts(j));
139 seq_puts(p, " PowerPC Thermal Assist (cpu temp)\n");
142 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
143 /* should this be per processor send/receive? */
144 seq_printf(p, "IPI (recv/sent): %10u/%u\n",
145 atomic_read(&ipi_recv), atomic_read(&ipi_sent));
147 #endif /* CONFIG_PPC32 */
148 seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
153 #ifdef CONFIG_HOTPLUG_CPU
154 void fixup_irqs(cpumask_t map)
162 if (irq_desc[irq].status & IRQ_PER_CPU)
165 cpus_and(mask, irq_desc[irq].affinity, map);
166 if (any_online_cpu(mask) == NR_CPUS) {
167 printk("Breaking affinity for irq %i\n", irq);
170 if (irq_desc[irq].chip->set_affinity)
171 irq_desc[irq].chip->set_affinity(irq, mask);
172 else if (irq_desc[irq].action && !(warned++))
173 printk("Cannot set affinity for irq %i\n", irq);
182 void do_IRQ(struct pt_regs *regs)
185 #ifdef CONFIG_IRQSTACKS
186 struct thread_info *curtp, *irqtp;
191 #ifdef CONFIG_DEBUG_STACKOVERFLOW
192 /* Debugging check for stack overflow: is there less than 2KB free? */
196 sp = __get_SP() & (THREAD_SIZE-1);
198 if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
199 printk("do_IRQ: stack overflow: %ld\n",
200 sp - sizeof(struct thread_info));
207 * Every platform is required to implement ppc_md.get_irq.
208 * This function will either return an irq number or -1 to
209 * indicate there are no more pending.
210 * The value -2 is for buggy hardware and means that this IRQ
211 * has already been handled. -- Tom
213 irq = ppc_md.get_irq(regs);
216 #ifdef CONFIG_IRQSTACKS
217 /* Switch to the irq stack to handle this */
218 curtp = current_thread_info();
219 irqtp = hardirq_ctx[smp_processor_id()];
220 if (curtp != irqtp) {
221 struct irq_desc *desc = irq_desc + irq;
222 void *handler = desc->handle_irq;
225 irqtp->task = curtp->task;
227 call_handle_irq(irq, desc, regs, irqtp, handler);
230 set_bits(irqtp->flags, &curtp->flags);
233 generic_handle_irq(irq, regs);
234 } else if (irq != -2)
235 /* That's not SMP safe ... but who cares ? */
236 ppc_spurious_interrupts++;
240 #ifdef CONFIG_PPC_ISERIES
241 if (get_lppaca()->int_dword.fields.decr_int) {
242 get_lppaca()->int_dword.fields.decr_int = 0;
243 /* Signal a fake decrementer interrupt */
244 timer_interrupt(regs);
249 void __init init_IRQ(void)
259 * Virtual IRQ mapping code, used on systems with XICS interrupt controllers.
262 #define UNDEFINED_IRQ 0xffffffff
263 unsigned int virt_irq_to_real_map[NR_IRQS];
266 * Don't use virtual irqs 0, 1, 2 for devices.
267 * The pcnet32 driver considers interrupt numbers < 2 to be invalid,
268 * and 2 is the XICS IPI interrupt.
269 * We limit virtual irqs to __irq_offet_value less than virt_irq_max so
270 * that when we offset them we don't end up with an interrupt
271 * number >= virt_irq_max.
273 #define MIN_VIRT_IRQ 3
275 unsigned int virt_irq_max;
276 static unsigned int max_virt_irq;
277 static unsigned int nr_virt_irqs;
284 if ((virt_irq_max == 0) || (virt_irq_max > (NR_IRQS - 1)))
285 virt_irq_max = NR_IRQS - 1;
286 max_virt_irq = virt_irq_max - __irq_offset_value;
287 nr_virt_irqs = max_virt_irq - MIN_VIRT_IRQ + 1;
289 for (i = 0; i < NR_IRQS; i++)
290 virt_irq_to_real_map[i] = UNDEFINED_IRQ;
293 /* Create a mapping for a real_irq if it doesn't already exist.
294 * Return the virtual irq as a convenience.
296 int virt_irq_create_mapping(unsigned int real_irq)
298 unsigned int virq, first_virq;
301 if (ppc64_interrupt_controller == IC_OPEN_PIC)
302 return real_irq; /* no mapping for openpic (for now) */
304 if (ppc64_interrupt_controller == IC_CELL_PIC)
305 return real_irq; /* no mapping for iic either */
307 /* don't map interrupts < MIN_VIRT_IRQ */
308 if (real_irq < MIN_VIRT_IRQ) {
309 virt_irq_to_real_map[real_irq] = real_irq;
313 /* map to a number between MIN_VIRT_IRQ and max_virt_irq */
315 if (virq > max_virt_irq)
316 virq = (virq % nr_virt_irqs) + MIN_VIRT_IRQ;
318 /* search for this number or a free slot */
320 while (virt_irq_to_real_map[virq] != UNDEFINED_IRQ) {
321 if (virt_irq_to_real_map[virq] == real_irq)
323 if (++virq > max_virt_irq)
325 if (virq == first_virq)
326 goto nospace; /* oops, no free slots */
329 virt_irq_to_real_map[virq] = real_irq;
334 printk(KERN_CRIT "Interrupt table is full\n");
335 printk(KERN_CRIT "Increase virt_irq_max (currently %d) "
336 "in your kernel sources and rebuild.\n", virt_irq_max);
343 * In most cases will get a hit on the very first slot checked in the
344 * virt_irq_to_real_map. Only when there are a large number of
345 * IRQs will this be expensive.
347 unsigned int real_irq_to_virt_slowpath(unsigned int real_irq)
350 unsigned int first_virq;
354 if (virq > max_virt_irq)
355 virq = (virq % nr_virt_irqs) + MIN_VIRT_IRQ;
360 if (virt_irq_to_real_map[virq] == real_irq)
365 if (virq >= max_virt_irq)
368 } while (first_virq != virq);
373 #endif /* CONFIG_PPC64 */
375 #ifdef CONFIG_IRQSTACKS
376 struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
377 struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
379 void irq_ctx_init(void)
381 struct thread_info *tp;
384 for_each_possible_cpu(i) {
385 memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
388 tp->preempt_count = SOFTIRQ_OFFSET;
390 memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
393 tp->preempt_count = HARDIRQ_OFFSET;
397 static inline void do_softirq_onstack(void)
399 struct thread_info *curtp, *irqtp;
401 curtp = current_thread_info();
402 irqtp = softirq_ctx[smp_processor_id()];
403 irqtp->task = curtp->task;
404 call_do_softirq(irqtp);
409 #define do_softirq_onstack() __do_softirq()
410 #endif /* CONFIG_IRQSTACKS */
412 void do_softirq(void)
419 local_irq_save(flags);
421 if (local_softirq_pending()) {
422 account_system_vtime(current);
424 do_softirq_onstack();
425 account_system_vtime(current);
429 local_irq_restore(flags);
431 EXPORT_SYMBOL(do_softirq);
433 #ifdef CONFIG_PCI_MSI
434 int pci_enable_msi(struct pci_dev * pdev)
436 if (ppc_md.enable_msi)
437 return ppc_md.enable_msi(pdev);
442 void pci_disable_msi(struct pci_dev * pdev)
444 if (ppc_md.disable_msi)
445 ppc_md.disable_msi(pdev);
448 void pci_scan_msi_device(struct pci_dev *dev) {}
449 int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec) {return -1;}
450 void pci_disable_msix(struct pci_dev *dev) {}
451 void msi_remove_pci_irq_vectors(struct pci_dev *dev) {}
452 void disable_msi_mode(struct pci_dev *dev, int pos, int type) {}
453 void pci_no_msi(void) {}
458 static int __init setup_noirqdistrib(char *str)
464 __setup("noirqdistrib", setup_noirqdistrib);
465 #endif /* CONFIG_PPC64 */