1 /*
2 * Copyright (C) 2000,2001,2002,2003,2004 Broadcom Corporation
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18 #include <linux/kernel.h>
19 #include <linux/init.h>
20 #include <linux/linkage.h>
21 #include <linux/interrupt.h>
22 #include <linux/spinlock.h>
23 #include <linux/mm.h>
24 #include <linux/slab.h>
25 #include <linux/kernel_stat.h>
26
27 #include <asm/errno.h>
28 #include <asm/irq_regs.h>
29 #include <asm/signal.h>
30 #include <asm/system.h>
31 #include <asm/io.h>
32
33 #include <asm/sibyte/bcm1480_regs.h>
34 #include <asm/sibyte/bcm1480_int.h>
35 #include <asm/sibyte/bcm1480_scd.h>
36
37 #include <asm/sibyte/sb1250_uart.h>
38 #include <asm/sibyte/sb1250.h>
39
40 /*
41 * These are the routines that handle all the low level interrupt stuff.
42 * Actions handled here are: initialization of the interrupt map, requesting of
43 * interrupt lines by handlers, dispatching if interrupts to handlers, probing
44 * for interrupt lines
45 */
46
47
48 static void end_bcm1480_irq(unsigned int irq);
49 static void enable_bcm1480_irq(unsigned int irq);
50 static void disable_bcm1480_irq(unsigned int irq);
51 static void ack_bcm1480_irq(unsigned int irq);
52 #ifdef CONFIG_SMP
53 static void bcm1480_set_affinity(unsigned int irq, const struct cpumask *mask);
54 #endif
55
56 #ifdef CONFIG_PCI
57 extern unsigned long ht_eoi_space;
58 #endif
59
60 static struct irq_chip bcm1480_irq_type = {
61 .name = "BCM1480-IMR",
62 .ack = ack_bcm1480_irq,
63 .mask = disable_bcm1480_irq,
64 .mask_ack = ack_bcm1480_irq,
65 .unmask = enable_bcm1480_irq,
66 .end = end_bcm1480_irq,
67 #ifdef CONFIG_SMP
68 .set_affinity = bcm1480_set_affinity
69 #endif
70 };
71
72 /* Store the CPU id (not the logical number) */
73 int bcm1480_irq_owner[BCM1480_NR_IRQS];
74
75 DEFINE_SPINLOCK(bcm1480_imr_lock);
76
bcm1480_mask_irq(int cpu,int irq)77 void bcm1480_mask_irq(int cpu, int irq)
78 {
79 unsigned long flags, hl_spacing;
80 u64 cur_ints;
81
82 spin_lock_irqsave(&bcm1480_imr_lock, flags);
83 hl_spacing = 0;
84 if ((irq >= BCM1480_NR_IRQS_HALF) && (irq <= BCM1480_NR_IRQS)) {
85 hl_spacing = BCM1480_IMR_HL_SPACING;
86 irq -= BCM1480_NR_IRQS_HALF;
87 }
88 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
89 cur_ints |= (((u64) 1) << irq);
90 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
91 spin_unlock_irqrestore(&bcm1480_imr_lock, flags);
92 }
93
bcm1480_unmask_irq(int cpu,int irq)94 void bcm1480_unmask_irq(int cpu, int irq)
95 {
96 unsigned long flags, hl_spacing;
97 u64 cur_ints;
98
99 spin_lock_irqsave(&bcm1480_imr_lock, flags);
100 hl_spacing = 0;
101 if ((irq >= BCM1480_NR_IRQS_HALF) && (irq <= BCM1480_NR_IRQS)) {
102 hl_spacing = BCM1480_IMR_HL_SPACING;
103 irq -= BCM1480_NR_IRQS_HALF;
104 }
105 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
106 cur_ints &= ~(((u64) 1) << irq);
107 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
108 spin_unlock_irqrestore(&bcm1480_imr_lock, flags);
109 }
110
111 #ifdef CONFIG_SMP
bcm1480_set_affinity(unsigned int irq,const struct cpumask * mask)112 static void bcm1480_set_affinity(unsigned int irq, const struct cpumask *mask)
113 {
114 int i = 0, old_cpu, cpu, int_on, k;
115 u64 cur_ints;
116 struct irq_desc *desc = irq_desc + irq;
117 unsigned long flags;
118 unsigned int irq_dirty;
119
120 if (cpumask_weight(mask) != 1) {
121 printk("attempted to set irq affinity for irq %d to multiple CPUs\n", irq);
122 return;
123 }
124 i = cpumask_first(mask);
125
126 /* Convert logical CPU to physical CPU */
127 cpu = cpu_logical_map(i);
128
129 /* Protect against other affinity changers and IMR manipulation */
130 spin_lock_irqsave(&desc->lock, flags);
131 spin_lock(&bcm1480_imr_lock);
132
133 /* Swizzle each CPU's IMR (but leave the IP selection alone) */
134 old_cpu = bcm1480_irq_owner[irq];
135 irq_dirty = irq;
136 if ((irq_dirty >= BCM1480_NR_IRQS_HALF) && (irq_dirty <= BCM1480_NR_IRQS)) {
137 irq_dirty -= BCM1480_NR_IRQS_HALF;
138 }
139
140 for (k=0; k<2; k++) { /* Loop through high and low interrupt mask register */
141 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(old_cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
142 int_on = !(cur_ints & (((u64) 1) << irq_dirty));
143 if (int_on) {
144 /* If it was on, mask it */
145 cur_ints |= (((u64) 1) << irq_dirty);
146 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(old_cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
147 }
148 bcm1480_irq_owner[irq] = cpu;
149 if (int_on) {
150 /* unmask for the new CPU */
151 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
152 cur_ints &= ~(((u64) 1) << irq_dirty);
153 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
154 }
155 }
156 spin_unlock(&bcm1480_imr_lock);
157 spin_unlock_irqrestore(&desc->lock, flags);
158 }
159 #endif
160
161
162 /*****************************************************************************/
163
disable_bcm1480_irq(unsigned int irq)164 static void disable_bcm1480_irq(unsigned int irq)
165 {
166 bcm1480_mask_irq(bcm1480_irq_owner[irq], irq);
167 }
168
enable_bcm1480_irq(unsigned int irq)169 static void enable_bcm1480_irq(unsigned int irq)
170 {
171 bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq);
172 }
173
174
ack_bcm1480_irq(unsigned int irq)175 static void ack_bcm1480_irq(unsigned int irq)
176 {
177 u64 pending;
178 unsigned int irq_dirty;
179 int k;
180
181 /*
182 * If the interrupt was an HT interrupt, now is the time to
183 * clear it. NOTE: we assume the HT bridge was set up to
184 * deliver the interrupts to all CPUs (which makes affinity
185 * changing easier for us)
186 */
187 irq_dirty = irq;
188 if ((irq_dirty >= BCM1480_NR_IRQS_HALF) && (irq_dirty <= BCM1480_NR_IRQS)) {
189 irq_dirty -= BCM1480_NR_IRQS_HALF;
190 }
191 for (k=0; k<2; k++) { /* Loop through high and low LDT interrupts */
192 pending = __raw_readq(IOADDR(A_BCM1480_IMR_REGISTER(bcm1480_irq_owner[irq],
193 R_BCM1480_IMR_LDT_INTERRUPT_H + (k*BCM1480_IMR_HL_SPACING))));
194 pending &= ((u64)1 << (irq_dirty));
195 if (pending) {
196 #ifdef CONFIG_SMP
197 int i;
198 for (i=0; i<NR_CPUS; i++) {
199 /*
200 * Clear for all CPUs so an affinity switch
201 * doesn't find an old status
202 */
203 __raw_writeq(pending, IOADDR(A_BCM1480_IMR_REGISTER(cpu_logical_map(i),
204 R_BCM1480_IMR_LDT_INTERRUPT_CLR_H + (k*BCM1480_IMR_HL_SPACING))));
205 }
206 #else
207 __raw_writeq(pending, IOADDR(A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_LDT_INTERRUPT_CLR_H + (k*BCM1480_IMR_HL_SPACING))));
208 #endif
209
210 /*
211 * Generate EOI. For Pass 1 parts, EOI is a nop. For
212 * Pass 2, the LDT world may be edge-triggered, but
213 * this EOI shouldn't hurt. If they are
214 * level-sensitive, the EOI is required.
215 */
216 #ifdef CONFIG_PCI
217 if (ht_eoi_space)
218 *(uint32_t *)(ht_eoi_space+(irq<<16)+(7<<2)) = 0;
219 #endif
220 }
221 }
222 bcm1480_mask_irq(bcm1480_irq_owner[irq], irq);
223 }
224
225
end_bcm1480_irq(unsigned int irq)226 static void end_bcm1480_irq(unsigned int irq)
227 {
228 if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) {
229 bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq);
230 }
231 }
232
233
init_bcm1480_irqs(void)234 void __init init_bcm1480_irqs(void)
235 {
236 int i;
237
238 for (i = 0; i < BCM1480_NR_IRQS; i++) {
239 set_irq_chip(i, &bcm1480_irq_type);
240 bcm1480_irq_owner[i] = 0;
241 }
242 }
243
244 /*
245 * init_IRQ is called early in the boot sequence from init/main.c. It
246 * is responsible for setting up the interrupt mapper and installing the
247 * handler that will be responsible for dispatching interrupts to the
248 * "right" place.
249 */
250 /*
251 * For now, map all interrupts to IP[2]. We could save
252 * some cycles by parceling out system interrupts to different
253 * IP lines, but keep it simple for bringup. We'll also direct
254 * all interrupts to a single CPU; we should probably route
255 * PCI and LDT to one cpu and everything else to the other
256 * to balance the load a bit.
257 *
258 * On the second cpu, everything is set to IP5, which is
259 * ignored, EXCEPT the mailbox interrupt. That one is
260 * set to IP[2] so it is handled. This is needed so we
261 * can do cross-cpu function calls, as requred by SMP
262 */
263
264 #define IMR_IP2_VAL K_BCM1480_INT_MAP_I0
265 #define IMR_IP3_VAL K_BCM1480_INT_MAP_I1
266 #define IMR_IP4_VAL K_BCM1480_INT_MAP_I2
267 #define IMR_IP5_VAL K_BCM1480_INT_MAP_I3
268 #define IMR_IP6_VAL K_BCM1480_INT_MAP_I4
269
arch_init_irq(void)270 void __init arch_init_irq(void)
271 {
272 unsigned int i, cpu;
273 u64 tmp;
274 unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 |
275 STATUSF_IP1 | STATUSF_IP0;
276
277 /* Default everything to IP2 */
278 /* Start with _high registers which has no bit 0 interrupt source */
279 for (i = 1; i < BCM1480_NR_IRQS_HALF; i++) { /* was I0 */
280 for (cpu = 0; cpu < 4; cpu++) {
281 __raw_writeq(IMR_IP2_VAL,
282 IOADDR(A_BCM1480_IMR_REGISTER(cpu,
283 R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) + (i << 3)));
284 }
285 }
286
287 /* Now do _low registers */
288 for (i = 0; i < BCM1480_NR_IRQS_HALF; i++) {
289 for (cpu = 0; cpu < 4; cpu++) {
290 __raw_writeq(IMR_IP2_VAL,
291 IOADDR(A_BCM1480_IMR_REGISTER(cpu,
292 R_BCM1480_IMR_INTERRUPT_MAP_BASE_L) + (i << 3)));
293 }
294 }
295
296 init_bcm1480_irqs();
297
298 /*
299 * Map the high 16 bits of mailbox_0 registers to IP[3], for
300 * inter-cpu messages
301 */
302 /* Was I1 */
303 for (cpu = 0; cpu < 4; cpu++) {
304 __raw_writeq(IMR_IP3_VAL, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) +
305 (K_BCM1480_INT_MBOX_0_0 << 3)));
306 }
307
308
309 /* Clear the mailboxes. The firmware may leave them dirty */
310 for (cpu = 0; cpu < 4; cpu++) {
311 __raw_writeq(0xffffffffffffffffULL,
312 IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_MAILBOX_0_CLR_CPU)));
313 __raw_writeq(0xffffffffffffffffULL,
314 IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_MAILBOX_1_CLR_CPU)));
315 }
316
317
318 /* Mask everything except the high 16 bit of mailbox_0 registers for all cpus */
319 tmp = ~((u64) 0) ^ ( (((u64) 1) << K_BCM1480_INT_MBOX_0_0));
320 for (cpu = 0; cpu < 4; cpu++) {
321 __raw_writeq(tmp, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MASK_H)));
322 }
323 tmp = ~((u64) 0);
324 for (cpu = 0; cpu < 4; cpu++) {
325 __raw_writeq(tmp, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MASK_L)));
326 }
327
328 /*
329 * Note that the timer interrupts are also mapped, but this is
330 * done in bcm1480_time_init(). Also, the profiling driver
331 * does its own management of IP7.
332 */
333
334 /* Enable necessary IPs, disable the rest */
335 change_c0_status(ST0_IM, imask);
336 }
337
338 extern void bcm1480_mailbox_interrupt(void);
339
dispatch_ip2(void)340 static inline void dispatch_ip2(void)
341 {
342 unsigned long long mask_h, mask_l;
343 unsigned int cpu = smp_processor_id();
344 unsigned long base;
345
346 /*
347 * Default...we've hit an IP[2] interrupt, which means we've got to
348 * check the 1480 interrupt registers to figure out what to do. Need
349 * to detect which CPU we're on, now that smp_affinity is supported.
350 */
351 base = A_BCM1480_IMR_MAPPER(cpu);
352 mask_h = __raw_readq(
353 IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_H));
354 mask_l = __raw_readq(
355 IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_L));
356
357 if (mask_h) {
358 if (mask_h ^ 1)
359 do_IRQ(fls64(mask_h) - 1);
360 else if (mask_l)
361 do_IRQ(63 + fls64(mask_l));
362 }
363 }
364
plat_irq_dispatch(void)365 asmlinkage void plat_irq_dispatch(void)
366 {
367 unsigned int cpu = smp_processor_id();
368 unsigned int pending;
369
370 #ifdef CONFIG_SIBYTE_BCM1480_PROF
371 /* Set compare to count to silence count/compare timer interrupts */
372 write_c0_compare(read_c0_count());
373 #endif
374
375 pending = read_c0_cause() & read_c0_status();
376
377 #ifdef CONFIG_SIBYTE_BCM1480_PROF
378 if (pending & CAUSEF_IP7) /* Cpu performance counter interrupt */
379 sbprof_cpu_intr();
380 else
381 #endif
382
383 if (pending & CAUSEF_IP4)
384 do_IRQ(K_BCM1480_INT_TIMER_0 + cpu);
385 #ifdef CONFIG_SMP
386 else if (pending & CAUSEF_IP3)
387 bcm1480_mailbox_interrupt();
388 #endif
389
390 else if (pending & CAUSEF_IP2)
391 dispatch_ip2();
392 }
393