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-rw-r--r--arch/x86/kernel/i8259_64.c309
1 files changed, 0 insertions, 309 deletions
diff --git a/arch/x86/kernel/i8259_64.c b/arch/x86/kernel/i8259_64.c
index fa57a1568508..a95d2bd27e9d 100644
--- a/arch/x86/kernel/i8259_64.c
+++ b/arch/x86/kernel/i8259_64.c
@@ -87,315 +87,6 @@ static void (*__initdata interrupt[NR_VECTORS - FIRST_EXTERNAL_VECTOR])(void) =
87#undef IRQ 87#undef IRQ
88#undef IRQLIST_16 88#undef IRQLIST_16
89 89
90/*
91 * This is the 'legacy' 8259A Programmable Interrupt Controller,
92 * present in the majority of PC/AT boxes.
93 * plus some generic x86 specific things if generic specifics makes
94 * any sense at all.
95 * this file should become arch/i386/kernel/irq.c when the old irq.c
96 * moves to arch independent land
97 */
98
99static int i8259A_auto_eoi;
100DEFINE_SPINLOCK(i8259A_lock);
101static void mask_and_ack_8259A(unsigned int);
102
103static struct irq_chip i8259A_chip = {
104 .name = "XT-PIC",
105 .mask = disable_8259A_irq,
106 .disable = disable_8259A_irq,
107 .unmask = enable_8259A_irq,
108 .mask_ack = mask_and_ack_8259A,
109};
110
111/*
112 * 8259A PIC functions to handle ISA devices:
113 */
114
115/*
116 * This contains the irq mask for both 8259A irq controllers,
117 */
118unsigned int cached_irq_mask = 0xffff;
119
120/*
121 * Not all IRQs can be routed through the IO-APIC, eg. on certain (older)
122 * boards the timer interrupt is not really connected to any IO-APIC pin,
123 * it's fed to the master 8259A's IR0 line only.
124 *
125 * Any '1' bit in this mask means the IRQ is routed through the IO-APIC.
126 * this 'mixed mode' IRQ handling costs nothing because it's only used
127 * at IRQ setup time.
128 */
129unsigned long io_apic_irqs;
130
131void disable_8259A_irq(unsigned int irq)
132{
133 unsigned int mask = 1 << irq;
134 unsigned long flags;
135
136 spin_lock_irqsave(&i8259A_lock, flags);
137 cached_irq_mask |= mask;
138 if (irq & 8)
139 outb(cached_slave_mask, PIC_SLAVE_IMR);
140 else
141 outb(cached_master_mask, PIC_MASTER_IMR);
142 spin_unlock_irqrestore(&i8259A_lock, flags);
143}
144
145void enable_8259A_irq(unsigned int irq)
146{
147 unsigned int mask = ~(1 << irq);
148 unsigned long flags;
149
150 spin_lock_irqsave(&i8259A_lock, flags);
151 cached_irq_mask &= mask;
152 if (irq & 8)
153 outb(cached_slave_mask, PIC_SLAVE_IMR);
154 else
155 outb(cached_master_mask, PIC_MASTER_IMR);
156 spin_unlock_irqrestore(&i8259A_lock, flags);
157}
158
159int i8259A_irq_pending(unsigned int irq)
160{
161 unsigned int mask = 1<<irq;
162 unsigned long flags;
163 int ret;
164
165 spin_lock_irqsave(&i8259A_lock, flags);
166 if (irq < 8)
167 ret = inb(PIC_MASTER_CMD) & mask;
168 else
169 ret = inb(PIC_SLAVE_CMD) & (mask >> 8);
170 spin_unlock_irqrestore(&i8259A_lock, flags);
171
172 return ret;
173}
174
175void make_8259A_irq(unsigned int irq)
176{
177 disable_irq_nosync(irq);
178 io_apic_irqs &= ~(1<<irq);
179 set_irq_chip_and_handler_name(irq, &i8259A_chip, handle_level_irq,
180 "XT");
181 enable_irq(irq);
182}
183
184/*
185 * This function assumes to be called rarely. Switching between
186 * 8259A registers is slow.
187 * This has to be protected by the irq controller spinlock
188 * before being called.
189 */
190static inline int i8259A_irq_real(unsigned int irq)
191{
192 int value;
193 int irqmask = 1<<irq;
194
195 if (irq < 8) {
196 outb(0x0B,PIC_MASTER_CMD); /* ISR register */
197 value = inb(PIC_MASTER_CMD) & irqmask;
198 outb(0x0A,PIC_MASTER_CMD); /* back to the IRR register */
199 return value;
200 }
201 outb(0x0B,PIC_SLAVE_CMD); /* ISR register */
202 value = inb(PIC_SLAVE_CMD) & (irqmask >> 8);
203 outb(0x0A,PIC_SLAVE_CMD); /* back to the IRR register */
204 return value;
205}
206
207/*
208 * Careful! The 8259A is a fragile beast, it pretty
209 * much _has_ to be done exactly like this (mask it
210 * first, _then_ send the EOI, and the order of EOI
211 * to the two 8259s is important!
212 */
213static void mask_and_ack_8259A(unsigned int irq)
214{
215 unsigned int irqmask = 1 << irq;
216 unsigned long flags;
217
218 spin_lock_irqsave(&i8259A_lock, flags);
219 /*
220 * Lightweight spurious IRQ detection. We do not want
221 * to overdo spurious IRQ handling - it's usually a sign
222 * of hardware problems, so we only do the checks we can
223 * do without slowing down good hardware unnecessarily.
224 *
225 * Note that IRQ7 and IRQ15 (the two spurious IRQs
226 * usually resulting from the 8259A-1|2 PICs) occur
227 * even if the IRQ is masked in the 8259A. Thus we
228 * can check spurious 8259A IRQs without doing the
229 * quite slow i8259A_irq_real() call for every IRQ.
230 * This does not cover 100% of spurious interrupts,
231 * but should be enough to warn the user that there
232 * is something bad going on ...
233 */
234 if (cached_irq_mask & irqmask)
235 goto spurious_8259A_irq;
236 cached_irq_mask |= irqmask;
237
238handle_real_irq:
239 if (irq & 8) {
240 inb(PIC_SLAVE_IMR); /* DUMMY - (do we need this?) */
241 outb(cached_slave_mask, PIC_SLAVE_IMR);
242 /* 'Specific EOI' to slave */
243 outb(0x60+(irq&7),PIC_SLAVE_CMD);
244 /* 'Specific EOI' to master-IRQ2 */
245 outb(0x60+PIC_CASCADE_IR,PIC_MASTER_CMD);
246 } else {
247 inb(PIC_MASTER_IMR); /* DUMMY - (do we need this?) */
248 outb(cached_master_mask, PIC_MASTER_IMR);
249 /* 'Specific EOI' to master */
250 outb(0x60+irq,PIC_MASTER_CMD);
251 }
252 spin_unlock_irqrestore(&i8259A_lock, flags);
253 return;
254
255spurious_8259A_irq:
256 /*
257 * this is the slow path - should happen rarely.
258 */
259 if (i8259A_irq_real(irq))
260 /*
261 * oops, the IRQ _is_ in service according to the
262 * 8259A - not spurious, go handle it.
263 */
264 goto handle_real_irq;
265
266 {
267 static int spurious_irq_mask;
268 /*
269 * At this point we can be sure the IRQ is spurious,
270 * lets ACK and report it. [once per IRQ]
271 */
272 if (!(spurious_irq_mask & irqmask)) {
273 printk(KERN_DEBUG
274 "spurious 8259A interrupt: IRQ%d.\n", irq);
275 spurious_irq_mask |= irqmask;
276 }
277 atomic_inc(&irq_err_count);
278 /*
279 * Theoretically we do not have to handle this IRQ,
280 * but in Linux this does not cause problems and is
281 * simpler for us.
282 */
283 goto handle_real_irq;
284 }
285}
286
287static char irq_trigger[2];
288/**
289 * ELCR registers (0x4d0, 0x4d1) control edge/level of IRQ
290 */
291static void restore_ELCR(char *trigger)
292{
293 outb(trigger[0], 0x4d0);
294 outb(trigger[1], 0x4d1);
295}
296
297static void save_ELCR(char *trigger)
298{
299 /* IRQ 0,1,2,8,13 are marked as reserved */
300 trigger[0] = inb(0x4d0) & 0xF8;
301 trigger[1] = inb(0x4d1) & 0xDE;
302}
303
304static int i8259A_resume(struct sys_device *dev)
305{
306 init_8259A(i8259A_auto_eoi);
307 restore_ELCR(irq_trigger);
308 return 0;
309}
310
311static int i8259A_suspend(struct sys_device *dev, pm_message_t state)
312{
313 save_ELCR(irq_trigger);
314 return 0;
315}
316
317static int i8259A_shutdown(struct sys_device *dev)
318{
319 /* Put the i8259A into a quiescent state that
320 * the kernel initialization code can get it
321 * out of.
322 */
323 outb(0xff, PIC_MASTER_IMR); /* mask all of 8259A-1 */
324 outb(0xff, PIC_SLAVE_IMR); /* mask all of 8259A-1 */
325 return 0;
326}
327
328static struct sysdev_class i8259_sysdev_class = {
329 .name = "i8259",
330 .suspend = i8259A_suspend,
331 .resume = i8259A_resume,
332 .shutdown = i8259A_shutdown,
333};
334
335static struct sys_device device_i8259A = {
336 .id = 0,
337 .cls = &i8259_sysdev_class,
338};
339
340static int __init i8259A_init_sysfs(void)
341{
342 int error = sysdev_class_register(&i8259_sysdev_class);
343 if (!error)
344 error = sysdev_register(&device_i8259A);
345 return error;
346}
347
348device_initcall(i8259A_init_sysfs);
349
350void init_8259A(int auto_eoi)
351{
352 unsigned long flags;
353
354 i8259A_auto_eoi = auto_eoi;
355
356 spin_lock_irqsave(&i8259A_lock, flags);
357
358 outb(0xff, PIC_MASTER_IMR); /* mask all of 8259A-1 */
359 outb(0xff, PIC_SLAVE_IMR); /* mask all of 8259A-2 */
360
361 /*
362 * outb_pic - this has to work on a wide range of PC hardware.
363 */
364 outb_pic(0x11, PIC_MASTER_CMD); /* ICW1: select 8259A-1 init */
365 /* ICW2: 8259A-1 IR0-7 mapped to 0x30-0x37 */
366 outb_pic(IRQ0_VECTOR, PIC_MASTER_IMR);
367 /* 8259A-1 (the master) has a slave on IR2 */
368 outb_pic(0x04, PIC_MASTER_IMR);
369 if (auto_eoi) /* master does Auto EOI */
370 outb_pic(MASTER_ICW4_DEFAULT | PIC_ICW4_AEOI, PIC_MASTER_IMR);
371 else /* master expects normal EOI */
372 outb_pic(MASTER_ICW4_DEFAULT, PIC_MASTER_IMR);
373
374 outb_pic(0x11, PIC_SLAVE_CMD); /* ICW1: select 8259A-2 init */
375 /* ICW2: 8259A-2 IR0-7 mapped to 0x38-0x3f */
376 outb_pic(IRQ8_VECTOR, PIC_SLAVE_IMR);
377 /* 8259A-2 is a slave on master's IR2 */
378 outb_pic(PIC_CASCADE_IR, PIC_SLAVE_IMR);
379 /* (slave's support for AEOI in flat mode is to be investigated) */
380 outb_pic(SLAVE_ICW4_DEFAULT, PIC_SLAVE_IMR);
381
382 if (auto_eoi)
383 /*
384 * In AEOI mode we just have to mask the interrupt
385 * when acking.
386 */
387 i8259A_chip.mask_ack = disable_8259A_irq;
388 else
389 i8259A_chip.mask_ack = mask_and_ack_8259A;
390
391 udelay(100); /* wait for 8259A to initialize */
392
393 outb(cached_master_mask, PIC_MASTER_IMR); /* restore master IRQ mask */
394 outb(cached_slave_mask, PIC_SLAVE_IMR); /* restore slave IRQ mask */
395
396 spin_unlock_irqrestore(&i8259A_lock, flags);
397}
398
399 90
400 91
401 92
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