2 * Copyright (C) 2000,2001,2002,2003,2004 Broadcom Corporation
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.
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.
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.
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>
24 #include <linux/slab.h>
25 #include <linux/kernel_stat.h>
27 #include <asm/errno.h>
28 #include <asm/signal.h>
29 #include <asm/system.h>
30 #include <asm/ptrace.h>
33 #include <asm/sibyte/bcm1480_regs.h>
34 #include <asm/sibyte/bcm1480_int.h>
35 #include <asm/sibyte/bcm1480_scd.h>
37 #include <asm/sibyte/sb1250_uart.h>
38 #include <asm/sibyte/sb1250.h>
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
48 #define shutdown_bcm1480_irq disable_bcm1480_irq
49 static void end_bcm1480_irq(unsigned int irq);
50 static void enable_bcm1480_irq(unsigned int irq);
51 static void disable_bcm1480_irq(unsigned int irq);
52 static unsigned int startup_bcm1480_irq(unsigned int irq);
53 static void ack_bcm1480_irq(unsigned int irq);
55 static void bcm1480_set_affinity(unsigned int irq, cpumask_t mask);
59 extern unsigned long ht_eoi_space;
63 #include <asm/gdb-stub.h>
64 extern void breakpoint(void);
66 #ifdef CONFIG_GDB_CONSOLE
67 extern void register_gdb_console(void);
70 /* kgdb is on when configured. Pass "nokgdb" kernel arg to turn it off */
71 static int kgdb_flag = 1;
72 static int __init nokgdb(char *str)
77 __setup("nokgdb", nokgdb);
79 /* Default to UART1 */
81 #ifdef CONFIG_SIBYTE_SB1250_DUART
82 extern char sb1250_duart_present[];
86 static struct irq_chip bcm1480_irq_type = {
87 .typename = "BCM1480-IMR",
88 .startup = startup_bcm1480_irq,
89 .shutdown = shutdown_bcm1480_irq,
90 .enable = enable_bcm1480_irq,
91 .disable = disable_bcm1480_irq,
92 .ack = ack_bcm1480_irq,
93 .end = end_bcm1480_irq,
95 .set_affinity = bcm1480_set_affinity
99 /* Store the CPU id (not the logical number) */
100 int bcm1480_irq_owner[BCM1480_NR_IRQS];
102 DEFINE_SPINLOCK(bcm1480_imr_lock);
104 void bcm1480_mask_irq(int cpu, int irq)
107 u64 cur_ints,hl_spacing;
109 spin_lock_irqsave(&bcm1480_imr_lock, flags);
111 if ((irq >= BCM1480_NR_IRQS_HALF) && (irq <= BCM1480_NR_IRQS)) {
112 hl_spacing = BCM1480_IMR_HL_SPACING;
113 irq -= BCM1480_NR_IRQS_HALF;
115 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
116 cur_ints |= (((u64) 1) << irq);
117 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
118 spin_unlock_irqrestore(&bcm1480_imr_lock, flags);
121 void bcm1480_unmask_irq(int cpu, int irq)
124 u64 cur_ints,hl_spacing;
126 spin_lock_irqsave(&bcm1480_imr_lock, flags);
128 if ((irq >= BCM1480_NR_IRQS_HALF) && (irq <= BCM1480_NR_IRQS)) {
129 hl_spacing = BCM1480_IMR_HL_SPACING;
130 irq -= BCM1480_NR_IRQS_HALF;
132 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
133 cur_ints &= ~(((u64) 1) << irq);
134 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
135 spin_unlock_irqrestore(&bcm1480_imr_lock, flags);
139 static void bcm1480_set_affinity(unsigned int irq, cpumask_t mask)
141 int i = 0, old_cpu, cpu, int_on, k;
143 struct irq_desc *desc = irq_desc + irq;
145 unsigned int irq_dirty;
148 if (next_cpu(i, mask) <= NR_CPUS) {
149 printk("attempted to set irq affinity for irq %d to multiple CPUs\n", irq);
153 /* Convert logical CPU to physical CPU */
154 cpu = cpu_logical_map(i);
156 /* Protect against other affinity changers and IMR manipulation */
157 spin_lock_irqsave(&desc->lock, flags);
158 spin_lock(&bcm1480_imr_lock);
160 /* Swizzle each CPU's IMR (but leave the IP selection alone) */
161 old_cpu = bcm1480_irq_owner[irq];
163 if ((irq_dirty >= BCM1480_NR_IRQS_HALF) && (irq_dirty <= BCM1480_NR_IRQS)) {
164 irq_dirty -= BCM1480_NR_IRQS_HALF;
167 for (k=0; k<2; k++) { /* Loop through high and low interrupt mask register */
168 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(old_cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
169 int_on = !(cur_ints & (((u64) 1) << irq_dirty));
171 /* If it was on, mask it */
172 cur_ints |= (((u64) 1) << irq_dirty);
173 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(old_cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
175 bcm1480_irq_owner[irq] = cpu;
177 /* unmask for the new CPU */
178 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
179 cur_ints &= ~(((u64) 1) << irq_dirty);
180 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
183 spin_unlock(&bcm1480_imr_lock);
184 spin_unlock_irqrestore(&desc->lock, flags);
189 /*****************************************************************************/
191 static unsigned int startup_bcm1480_irq(unsigned int irq)
193 bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq);
195 return 0; /* never anything pending */
199 static void disable_bcm1480_irq(unsigned int irq)
201 bcm1480_mask_irq(bcm1480_irq_owner[irq], irq);
204 static void enable_bcm1480_irq(unsigned int irq)
206 bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq);
210 static void ack_bcm1480_irq(unsigned int irq)
213 unsigned int irq_dirty;
217 * If the interrupt was an HT interrupt, now is the time to
218 * clear it. NOTE: we assume the HT bridge was set up to
219 * deliver the interrupts to all CPUs (which makes affinity
220 * changing easier for us)
223 if ((irq_dirty >= BCM1480_NR_IRQS_HALF) && (irq_dirty <= BCM1480_NR_IRQS)) {
224 irq_dirty -= BCM1480_NR_IRQS_HALF;
226 for (k=0; k<2; k++) { /* Loop through high and low LDT interrupts */
227 pending = __raw_readq(IOADDR(A_BCM1480_IMR_REGISTER(bcm1480_irq_owner[irq],
228 R_BCM1480_IMR_LDT_INTERRUPT_H + (k*BCM1480_IMR_HL_SPACING))));
229 pending &= ((u64)1 << (irq_dirty));
233 for (i=0; i<NR_CPUS; i++) {
235 * Clear for all CPUs so an affinity switch
236 * doesn't find an old status
238 __raw_writeq(pending, IOADDR(A_BCM1480_IMR_REGISTER(cpu_logical_map(i),
239 R_BCM1480_IMR_LDT_INTERRUPT_CLR_H + (k*BCM1480_IMR_HL_SPACING))));
242 __raw_writeq(pending, IOADDR(A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_LDT_INTERRUPT_CLR_H + (k*BCM1480_IMR_HL_SPACING))));
246 * Generate EOI. For Pass 1 parts, EOI is a nop. For
247 * Pass 2, the LDT world may be edge-triggered, but
248 * this EOI shouldn't hurt. If they are
249 * level-sensitive, the EOI is required.
253 *(uint32_t *)(ht_eoi_space+(irq<<16)+(7<<2)) = 0;
257 bcm1480_mask_irq(bcm1480_irq_owner[irq], irq);
261 static void end_bcm1480_irq(unsigned int irq)
263 if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) {
264 bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq);
269 void __init init_bcm1480_irqs(void)
273 for (i = 0; i < NR_IRQS; i++) {
274 irq_desc[i].status = IRQ_DISABLED;
275 irq_desc[i].action = 0;
276 irq_desc[i].depth = 1;
277 if (i < BCM1480_NR_IRQS) {
278 irq_desc[i].chip = &bcm1480_irq_type;
279 bcm1480_irq_owner[i] = 0;
281 irq_desc[i].chip = &no_irq_chip;
287 static irqreturn_t bcm1480_dummy_handler(int irq, void *dev_id,
288 struct pt_regs *regs)
293 static struct irqaction bcm1480_dummy_action = {
294 .handler = bcm1480_dummy_handler,
296 .mask = CPU_MASK_NONE,
297 .name = "bcm1480-private",
302 int bcm1480_steal_irq(int irq)
304 struct irq_desc *desc = irq_desc + irq;
308 if (irq >= BCM1480_NR_IRQS)
311 spin_lock_irqsave(&desc->lock,flags);
312 /* Don't allow sharing at all for these */
313 if (desc->action != NULL)
316 desc->action = &bcm1480_dummy_action;
319 spin_unlock_irqrestore(&desc->lock,flags);
324 * init_IRQ is called early in the boot sequence from init/main.c. It
325 * is responsible for setting up the interrupt mapper and installing the
326 * handler that will be responsible for dispatching interrupts to the
330 * For now, map all interrupts to IP[2]. We could save
331 * some cycles by parceling out system interrupts to different
332 * IP lines, but keep it simple for bringup. We'll also direct
333 * all interrupts to a single CPU; we should probably route
334 * PCI and LDT to one cpu and everything else to the other
335 * to balance the load a bit.
337 * On the second cpu, everything is set to IP5, which is
338 * ignored, EXCEPT the mailbox interrupt. That one is
339 * set to IP[2] so it is handled. This is needed so we
340 * can do cross-cpu function calls, as requred by SMP
343 #define IMR_IP2_VAL K_BCM1480_INT_MAP_I0
344 #define IMR_IP3_VAL K_BCM1480_INT_MAP_I1
345 #define IMR_IP4_VAL K_BCM1480_INT_MAP_I2
346 #define IMR_IP5_VAL K_BCM1480_INT_MAP_I3
347 #define IMR_IP6_VAL K_BCM1480_INT_MAP_I4
349 void __init arch_init_irq(void)
354 unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 |
355 STATUSF_IP1 | STATUSF_IP0;
357 /* Default everything to IP2 */
358 /* Start with _high registers which has no bit 0 interrupt source */
359 for (i = 1; i < BCM1480_NR_IRQS_HALF; i++) { /* was I0 */
360 for (cpu = 0; cpu < 4; cpu++) {
361 __raw_writeq(IMR_IP2_VAL,
362 IOADDR(A_BCM1480_IMR_REGISTER(cpu,
363 R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) + (i << 3)));
367 /* Now do _low registers */
368 for (i = 0; i < BCM1480_NR_IRQS_HALF; i++) {
369 for (cpu = 0; cpu < 4; cpu++) {
370 __raw_writeq(IMR_IP2_VAL,
371 IOADDR(A_BCM1480_IMR_REGISTER(cpu,
372 R_BCM1480_IMR_INTERRUPT_MAP_BASE_L) + (i << 3)));
379 * Map the high 16 bits of mailbox_0 registers to IP[3], for
383 for (cpu = 0; cpu < 4; cpu++) {
384 __raw_writeq(IMR_IP3_VAL, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) +
385 (K_BCM1480_INT_MBOX_0_0 << 3)));
389 /* Clear the mailboxes. The firmware may leave them dirty */
390 for (cpu = 0; cpu < 4; cpu++) {
391 __raw_writeq(0xffffffffffffffffULL,
392 IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_MAILBOX_0_CLR_CPU)));
393 __raw_writeq(0xffffffffffffffffULL,
394 IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_MAILBOX_1_CLR_CPU)));
398 /* Mask everything except the high 16 bit of mailbox_0 registers for all cpus */
399 tmp = ~((u64) 0) ^ ( (((u64) 1) << K_BCM1480_INT_MBOX_0_0));
400 for (cpu = 0; cpu < 4; cpu++) {
401 __raw_writeq(tmp, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MASK_H)));
404 for (cpu = 0; cpu < 4; cpu++) {
405 __raw_writeq(tmp, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MASK_L)));
408 bcm1480_steal_irq(K_BCM1480_INT_MBOX_0_0);
411 * Note that the timer interrupts are also mapped, but this is
412 * done in bcm1480_time_init(). Also, the profiling driver
413 * does its own management of IP7.
417 imask |= STATUSF_IP6;
419 /* Enable necessary IPs, disable the rest */
420 change_c0_status(ST0_IM, imask);
424 kgdb_irq = K_BCM1480_INT_UART_0 + kgdb_port;
426 #ifdef CONFIG_SIBYTE_SB1250_DUART
427 sb1250_duart_present[kgdb_port] = 0;
429 /* Setup uart 1 settings, mapper */
431 __raw_writeq(M_DUART_IMR_BRK, IO_SPACE_BASE + A_DUART_IMRREG(kgdb_port));
433 bcm1480_steal_irq(kgdb_irq);
434 __raw_writeq(IMR_IP6_VAL,
435 IO_SPACE_BASE + A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) +
437 bcm1480_unmask_irq(0, kgdb_irq);
439 #ifdef CONFIG_GDB_CONSOLE
440 register_gdb_console();
442 prom_printf("Waiting for GDB on UART port %d\n", kgdb_port);
451 #include <linux/delay.h>
453 #define duart_out(reg, val) csr_out32(val, IOADDR(A_DUART_CHANREG(kgdb_port,reg)))
454 #define duart_in(reg) csr_in32(IOADDR(A_DUART_CHANREG(kgdb_port,reg)))
456 void bcm1480_kgdb_interrupt(struct pt_regs *regs)
459 * Clear break-change status (allow some time for the remote
460 * host to stop the break, since we would see another
461 * interrupt on the end-of-break too)
463 kstat.irqs[smp_processor_id()][kgdb_irq]++;
465 duart_out(R_DUART_CMD, V_DUART_MISC_CMD_RESET_BREAK_INT |
466 M_DUART_RX_EN | M_DUART_TX_EN);
467 set_async_breakpoint(®s->cp0_epc);
470 #endif /* CONFIG_KGDB */
472 static inline int dclz(unsigned long long x)
487 extern void bcm1480_timer_interrupt(struct pt_regs *regs);
488 extern void bcm1480_mailbox_interrupt(struct pt_regs *regs);
489 extern void bcm1480_kgdb_interrupt(struct pt_regs *regs);
491 asmlinkage void plat_irq_dispatch(struct pt_regs *regs)
493 unsigned int pending;
495 #ifdef CONFIG_SIBYTE_BCM1480_PROF
496 /* Set compare to count to silence count/compare timer interrupts */
497 write_c0_compare(read_c0_count());
500 pending = read_c0_cause();
502 #ifdef CONFIG_SIBYTE_BCM1480_PROF
503 if (pending & CAUSEF_IP7) /* Cpu performance counter interrupt */
504 sbprof_cpu_intr(exception_epc(regs));
508 if (pending & CAUSEF_IP4)
509 bcm1480_timer_interrupt(regs);
512 else if (pending & CAUSEF_IP3)
513 bcm1480_mailbox_interrupt(regs);
517 else if (pending & CAUSEF_IP6)
518 bcm1480_kgdb_interrupt(regs); /* KGDB (uart 1) */
521 else if (pending & CAUSEF_IP2) {
522 unsigned long long mask_h, mask_l;
526 * Default...we've hit an IP[2] interrupt, which means we've
527 * got to check the 1480 interrupt registers to figure out what
528 * to do. Need to detect which CPU we're on, now that
529 * smp_affinity is supported.
531 base = A_BCM1480_IMR_MAPPER(smp_processor_id());
532 mask_h = __raw_readq(
533 IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_H));
534 mask_l = __raw_readq(
535 IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_L));
539 do_IRQ(63 - dclz(mask_h), regs);
541 do_IRQ(127 - dclz(mask_l), regs);