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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/parisc/kernel/irq.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/parisc/kernel/irq.c')
-rw-r--r--arch/parisc/kernel/irq.c343
1 files changed, 343 insertions, 0 deletions
diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c
new file mode 100644
index 000000000000..006385dbee66
--- /dev/null
+++ b/arch/parisc/kernel/irq.c
@@ -0,0 +1,343 @@
1/*
2 * Code to handle x86 style IRQs plus some generic interrupt stuff.
3 *
4 * Copyright (C) 1992 Linus Torvalds
5 * Copyright (C) 1994, 1995, 1996, 1997, 1998 Ralf Baechle
6 * Copyright (C) 1999 SuSE GmbH (Philipp Rumpf, prumpf@tux.org)
7 * Copyright (C) 1999-2000 Grant Grundler
8 * Copyright (c) 2005 Matthew Wilcox
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2, or (at your option)
13 * any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 */
24#include <linux/bitops.h>
25#include <linux/config.h>
26#include <linux/errno.h>
27#include <linux/init.h>
28#include <linux/interrupt.h>
29#include <linux/kernel_stat.h>
30#include <linux/seq_file.h>
31#include <linux/spinlock.h>
32#include <linux/types.h>
33
34#undef PARISC_IRQ_CR16_COUNTS
35
36extern irqreturn_t timer_interrupt(int, void *, struct pt_regs *);
37extern irqreturn_t ipi_interrupt(int, void *, struct pt_regs *);
38
39#define EIEM_MASK(irq) (1UL<<(CPU_IRQ_MAX - irq))
40
41/* Bits in EIEM correlate with cpu_irq_action[].
42** Numbered *Big Endian*! (ie bit 0 is MSB)
43*/
44static volatile unsigned long cpu_eiem = 0;
45
46static void cpu_set_eiem(void *info)
47{
48 set_eiem((unsigned long) info);
49}
50
51static inline void cpu_disable_irq(unsigned int irq)
52{
53 unsigned long eirr_bit = EIEM_MASK(irq);
54
55 cpu_eiem &= ~eirr_bit;
56 on_each_cpu(cpu_set_eiem, (void *) cpu_eiem, 1, 1);
57}
58
59static void cpu_enable_irq(unsigned int irq)
60{
61 unsigned long eirr_bit = EIEM_MASK(irq);
62
63 mtctl(eirr_bit, 23); /* clear EIRR bit before unmasking */
64 cpu_eiem |= eirr_bit;
65 on_each_cpu(cpu_set_eiem, (void *) cpu_eiem, 1, 1);
66}
67
68static unsigned int cpu_startup_irq(unsigned int irq)
69{
70 cpu_enable_irq(irq);
71 return 0;
72}
73
74void no_ack_irq(unsigned int irq) { }
75void no_end_irq(unsigned int irq) { }
76
77static struct hw_interrupt_type cpu_interrupt_type = {
78 .typename = "CPU",
79 .startup = cpu_startup_irq,
80 .shutdown = cpu_disable_irq,
81 .enable = cpu_enable_irq,
82 .disable = cpu_disable_irq,
83 .ack = no_ack_irq,
84 .end = no_end_irq,
85// .set_affinity = cpu_set_affinity_irq,
86};
87
88int show_interrupts(struct seq_file *p, void *v)
89{
90 int i = *(loff_t *) v, j;
91 unsigned long flags;
92
93 if (i == 0) {
94 seq_puts(p, " ");
95 for_each_online_cpu(j)
96 seq_printf(p, " CPU%d", j);
97
98#ifdef PARISC_IRQ_CR16_COUNTS
99 seq_printf(p, " [min/avg/max] (CPU cycle counts)");
100#endif
101 seq_putc(p, '\n');
102 }
103
104 if (i < NR_IRQS) {
105 struct irqaction *action;
106
107 spin_lock_irqsave(&irq_desc[i].lock, flags);
108 action = irq_desc[i].action;
109 if (!action)
110 goto skip;
111 seq_printf(p, "%3d: ", i);
112#ifdef CONFIG_SMP
113 for_each_online_cpu(j)
114 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
115#else
116 seq_printf(p, "%10u ", kstat_irqs(i));
117#endif
118
119 seq_printf(p, " %14s", irq_desc[i].handler->typename);
120#ifndef PARISC_IRQ_CR16_COUNTS
121 seq_printf(p, " %s", action->name);
122
123 while ((action = action->next))
124 seq_printf(p, ", %s", action->name);
125#else
126 for ( ;action; action = action->next) {
127 unsigned int k, avg, min, max;
128
129 min = max = action->cr16_hist[0];
130
131 for (avg = k = 0; k < PARISC_CR16_HIST_SIZE; k++) {
132 int hist = action->cr16_hist[k];
133
134 if (hist) {
135 avg += hist;
136 } else
137 break;
138
139 if (hist > max) max = hist;
140 if (hist < min) min = hist;
141 }
142
143 avg /= k;
144 seq_printf(p, " %s[%d/%d/%d]", action->name,
145 min,avg,max);
146 }
147#endif
148
149 seq_putc(p, '\n');
150 skip:
151 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
152 }
153
154 return 0;
155}
156
157
158
159/*
160** The following form a "set": Virtual IRQ, Transaction Address, Trans Data.
161** Respectively, these map to IRQ region+EIRR, Processor HPA, EIRR bit.
162**
163** To use txn_XXX() interfaces, get a Virtual IRQ first.
164** Then use that to get the Transaction address and data.
165*/
166
167int cpu_claim_irq(unsigned int irq, struct hw_interrupt_type *type, void *data)
168{
169 if (irq_desc[irq].action)
170 return -EBUSY;
171 if (irq_desc[irq].handler != &cpu_interrupt_type)
172 return -EBUSY;
173
174 if (type) {
175 irq_desc[irq].handler = type;
176 irq_desc[irq].handler_data = data;
177 cpu_interrupt_type.enable(irq);
178 }
179 return 0;
180}
181
182int txn_claim_irq(int irq)
183{
184 return cpu_claim_irq(irq, NULL, NULL) ? -1 : irq;
185}
186
187/*
188 * The bits_wide parameter accommodates the limitations of the HW/SW which
189 * use these bits:
190 * Legacy PA I/O (GSC/NIO): 5 bits (architected EIM register)
191 * V-class (EPIC): 6 bits
192 * N/L/A-class (iosapic): 8 bits
193 * PCI 2.2 MSI: 16 bits
194 * Some PCI devices: 32 bits (Symbios SCSI/ATM/HyperFabric)
195 *
196 * On the service provider side:
197 * o PA 1.1 (and PA2.0 narrow mode) 5-bits (width of EIR register)
198 * o PA 2.0 wide mode 6-bits (per processor)
199 * o IA64 8-bits (0-256 total)
200 *
201 * So a Legacy PA I/O device on a PA 2.0 box can't use all the bits supported
202 * by the processor...and the N/L-class I/O subsystem supports more bits than
203 * PA2.0 has. The first case is the problem.
204 */
205int txn_alloc_irq(unsigned int bits_wide)
206{
207 int irq;
208
209 /* never return irq 0 cause that's the interval timer */
210 for (irq = CPU_IRQ_BASE + 1; irq <= CPU_IRQ_MAX; irq++) {
211 if (cpu_claim_irq(irq, NULL, NULL) < 0)
212 continue;
213 if ((irq - CPU_IRQ_BASE) >= (1 << bits_wide))
214 continue;
215 return irq;
216 }
217
218 /* unlikely, but be prepared */
219 return -1;
220}
221
222unsigned long txn_alloc_addr(unsigned int virt_irq)
223{
224 static int next_cpu = -1;
225
226 next_cpu++; /* assign to "next" CPU we want this bugger on */
227
228 /* validate entry */
229 while ((next_cpu < NR_CPUS) && (!cpu_data[next_cpu].txn_addr ||
230 !cpu_online(next_cpu)))
231 next_cpu++;
232
233 if (next_cpu >= NR_CPUS)
234 next_cpu = 0; /* nothing else, assign monarch */
235
236 return cpu_data[next_cpu].txn_addr;
237}
238
239
240unsigned int txn_alloc_data(unsigned int virt_irq)
241{
242 return virt_irq - CPU_IRQ_BASE;
243}
244
245/* ONLY called from entry.S:intr_extint() */
246void do_cpu_irq_mask(struct pt_regs *regs)
247{
248 unsigned long eirr_val;
249
250 irq_enter();
251
252 /*
253 * Only allow interrupt processing to be interrupted by the
254 * timer tick
255 */
256 set_eiem(EIEM_MASK(TIMER_IRQ));
257
258 /* 1) only process IRQs that are enabled/unmasked (cpu_eiem)
259 * 2) We loop here on EIRR contents in order to avoid
260 * nested interrupts or having to take another interrupt
261 * when we could have just handled it right away.
262 */
263 for (;;) {
264 unsigned long bit = (1UL << (BITS_PER_LONG - 1));
265 unsigned int irq;
266 eirr_val = mfctl(23) & cpu_eiem;
267 if (!eirr_val)
268 break;
269
270 if (eirr_val & EIEM_MASK(TIMER_IRQ))
271 set_eiem(0);
272
273 mtctl(eirr_val, 23); /* reset bits we are going to process */
274
275 /* Work our way from MSb to LSb...same order we alloc EIRs */
276 for (irq = TIMER_IRQ; eirr_val && bit; bit>>=1, irq++) {
277 if (!(bit & eirr_val))
278 continue;
279
280 /* clear bit in mask - can exit loop sooner */
281 eirr_val &= ~bit;
282
283 __do_IRQ(irq, regs);
284 }
285 }
286 set_eiem(cpu_eiem);
287 irq_exit();
288}
289
290
291static struct irqaction timer_action = {
292 .handler = timer_interrupt,
293 .name = "timer",
294};
295
296#ifdef CONFIG_SMP
297static struct irqaction ipi_action = {
298 .handler = ipi_interrupt,
299 .name = "IPI",
300};
301#endif
302
303static void claim_cpu_irqs(void)
304{
305 int i;
306 for (i = CPU_IRQ_BASE; i <= CPU_IRQ_MAX; i++) {
307 irq_desc[i].handler = &cpu_interrupt_type;
308 }
309
310 irq_desc[TIMER_IRQ].action = &timer_action;
311 irq_desc[TIMER_IRQ].status |= IRQ_PER_CPU;
312#ifdef CONFIG_SMP
313 irq_desc[IPI_IRQ].action = &ipi_action;
314 irq_desc[IPI_IRQ].status = IRQ_PER_CPU;
315#endif
316}
317
318void __init init_IRQ(void)
319{
320 local_irq_disable(); /* PARANOID - should already be disabled */
321 mtctl(~0UL, 23); /* EIRR : clear all pending external intr */
322 claim_cpu_irqs();
323#ifdef CONFIG_SMP
324 if (!cpu_eiem)
325 cpu_eiem = EIEM_MASK(IPI_IRQ) | EIEM_MASK(TIMER_IRQ);
326#else
327 cpu_eiem = EIEM_MASK(TIMER_IRQ);
328#endif
329 set_eiem(cpu_eiem); /* EIEM : enable all external intr */
330
331}
332
333void hw_resend_irq(struct hw_interrupt_type *type, unsigned int irq)
334{
335 /* XXX: Needs to be written. We managed without it so far, but
336 * we really ought to write it.
337 */
338}
339
340void ack_bad_irq(unsigned int irq)
341{
342 printk("unexpected IRQ %d\n", irq);
343}