2 * Copyright (C) 2000, 2001, 2002, 2003 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>
23 #include <linux/smp.h>
25 #include <linux/kernel_stat.h>
27 #include <asm/errno.h>
28 #include <asm/signal.h>
29 #include <asm/system.h>
33 #include <asm/sibyte/sb1250_regs.h>
34 #include <asm/sibyte/sb1250_int.h>
35 #include <asm/sibyte/sb1250_uart.h>
36 #include <asm/sibyte/sb1250_scd.h>
37 #include <asm/sibyte/sb1250.h>
40 * These are the routines that handle all the low level interrupt stuff.
41 * Actions handled here are: initialization of the interrupt map, requesting of
42 * interrupt lines by handlers, dispatching if interrupts to handlers, probing
47 static void end_sb1250_irq(unsigned int irq
);
48 static void enable_sb1250_irq(unsigned int irq
);
49 static void disable_sb1250_irq(unsigned int irq
);
50 static void ack_sb1250_irq(unsigned int irq
);
52 static int sb1250_set_affinity(unsigned int irq
, const struct cpumask
*mask
);
55 #ifdef CONFIG_SIBYTE_HAS_LDT
56 extern unsigned long ldt_eoi_space
;
59 static struct irq_chip sb1250_irq_type
= {
61 .ack
= ack_sb1250_irq
,
62 .mask
= disable_sb1250_irq
,
63 .mask_ack
= ack_sb1250_irq
,
64 .unmask
= enable_sb1250_irq
,
65 .end
= end_sb1250_irq
,
67 .set_affinity
= sb1250_set_affinity
71 /* Store the CPU id (not the logical number) */
72 int sb1250_irq_owner
[SB1250_NR_IRQS
];
74 static DEFINE_RAW_SPINLOCK(sb1250_imr_lock
);
76 void sb1250_mask_irq(int cpu
, int irq
)
81 raw_spin_lock_irqsave(&sb1250_imr_lock
, flags
);
82 cur_ints
= ____raw_readq(IOADDR(A_IMR_MAPPER(cpu
) +
83 R_IMR_INTERRUPT_MASK
));
84 cur_ints
|= (((u64
) 1) << irq
);
85 ____raw_writeq(cur_ints
, IOADDR(A_IMR_MAPPER(cpu
) +
86 R_IMR_INTERRUPT_MASK
));
87 raw_spin_unlock_irqrestore(&sb1250_imr_lock
, flags
);
90 void sb1250_unmask_irq(int cpu
, int irq
)
95 raw_spin_lock_irqsave(&sb1250_imr_lock
, flags
);
96 cur_ints
= ____raw_readq(IOADDR(A_IMR_MAPPER(cpu
) +
97 R_IMR_INTERRUPT_MASK
));
98 cur_ints
&= ~(((u64
) 1) << irq
);
99 ____raw_writeq(cur_ints
, IOADDR(A_IMR_MAPPER(cpu
) +
100 R_IMR_INTERRUPT_MASK
));
101 raw_spin_unlock_irqrestore(&sb1250_imr_lock
, flags
);
105 static int sb1250_set_affinity(unsigned int irq
, const struct cpumask
*mask
)
107 int i
= 0, old_cpu
, cpu
, int_on
;
111 i
= cpumask_first(mask
);
113 /* Convert logical CPU to physical CPU */
114 cpu
= cpu_logical_map(i
);
116 /* Protect against other affinity changers and IMR manipulation */
117 raw_spin_lock_irqsave(&sb1250_imr_lock
, flags
);
119 /* Swizzle each CPU's IMR (but leave the IP selection alone) */
120 old_cpu
= sb1250_irq_owner
[irq
];
121 cur_ints
= ____raw_readq(IOADDR(A_IMR_MAPPER(old_cpu
) +
122 R_IMR_INTERRUPT_MASK
));
123 int_on
= !(cur_ints
& (((u64
) 1) << irq
));
125 /* If it was on, mask it */
126 cur_ints
|= (((u64
) 1) << irq
);
127 ____raw_writeq(cur_ints
, IOADDR(A_IMR_MAPPER(old_cpu
) +
128 R_IMR_INTERRUPT_MASK
));
130 sb1250_irq_owner
[irq
] = cpu
;
132 /* unmask for the new CPU */
133 cur_ints
= ____raw_readq(IOADDR(A_IMR_MAPPER(cpu
) +
134 R_IMR_INTERRUPT_MASK
));
135 cur_ints
&= ~(((u64
) 1) << irq
);
136 ____raw_writeq(cur_ints
, IOADDR(A_IMR_MAPPER(cpu
) +
137 R_IMR_INTERRUPT_MASK
));
139 raw_spin_unlock_irqrestore(&sb1250_imr_lock
, flags
);
145 /*****************************************************************************/
147 static void disable_sb1250_irq(unsigned int irq
)
149 sb1250_mask_irq(sb1250_irq_owner
[irq
], irq
);
152 static void enable_sb1250_irq(unsigned int irq
)
154 sb1250_unmask_irq(sb1250_irq_owner
[irq
], irq
);
158 static void ack_sb1250_irq(unsigned int irq
)
160 #ifdef CONFIG_SIBYTE_HAS_LDT
164 * If the interrupt was an HT interrupt, now is the time to
165 * clear it. NOTE: we assume the HT bridge was set up to
166 * deliver the interrupts to all CPUs (which makes affinity
167 * changing easier for us)
169 pending
= __raw_readq(IOADDR(A_IMR_REGISTER(sb1250_irq_owner
[irq
],
170 R_IMR_LDT_INTERRUPT
)));
171 pending
&= ((u64
)1 << (irq
));
174 for (i
=0; i
<NR_CPUS
; i
++) {
177 cpu
= cpu_logical_map(i
);
182 * Clear for all CPUs so an affinity switch
183 * doesn't find an old status
185 __raw_writeq(pending
,
186 IOADDR(A_IMR_REGISTER(cpu
,
187 R_IMR_LDT_INTERRUPT_CLR
)));
191 * Generate EOI. For Pass 1 parts, EOI is a nop. For
192 * Pass 2, the LDT world may be edge-triggered, but
193 * this EOI shouldn't hurt. If they are
194 * level-sensitive, the EOI is required.
196 *(uint32_t *)(ldt_eoi_space
+(irq
<<16)+(7<<2)) = 0;
199 sb1250_mask_irq(sb1250_irq_owner
[irq
], irq
);
203 static void end_sb1250_irq(unsigned int irq
)
205 if (!(irq_desc
[irq
].status
& (IRQ_DISABLED
| IRQ_INPROGRESS
))) {
206 sb1250_unmask_irq(sb1250_irq_owner
[irq
], irq
);
211 void __init
init_sb1250_irqs(void)
215 for (i
= 0; i
< SB1250_NR_IRQS
; i
++) {
216 set_irq_chip_and_handler(i
, &sb1250_irq_type
, handle_level_irq
);
217 sb1250_irq_owner
[i
] = 0;
223 * arch_init_irq is called early in the boot sequence from init/main.c via
224 * init_IRQ. It is responsible for setting up the interrupt mapper and
225 * installing the handler that will be responsible for dispatching interrupts
226 * to the "right" place.
229 * For now, map all interrupts to IP[2]. We could save
230 * some cycles by parceling out system interrupts to different
231 * IP lines, but keep it simple for bringup. We'll also direct
232 * all interrupts to a single CPU; we should probably route
233 * PCI and LDT to one cpu and everything else to the other
234 * to balance the load a bit.
236 * On the second cpu, everything is set to IP5, which is
237 * ignored, EXCEPT the mailbox interrupt. That one is
238 * set to IP[2] so it is handled. This is needed so we
239 * can do cross-cpu function calls, as required by SMP
242 #define IMR_IP2_VAL K_INT_MAP_I0
243 #define IMR_IP3_VAL K_INT_MAP_I1
244 #define IMR_IP4_VAL K_INT_MAP_I2
245 #define IMR_IP5_VAL K_INT_MAP_I3
246 #define IMR_IP6_VAL K_INT_MAP_I4
248 void __init
arch_init_irq(void)
253 unsigned int imask
= STATUSF_IP4
| STATUSF_IP3
| STATUSF_IP2
|
254 STATUSF_IP1
| STATUSF_IP0
;
256 /* Default everything to IP2 */
257 for (i
= 0; i
< SB1250_NR_IRQS
; i
++) { /* was I0 */
258 __raw_writeq(IMR_IP2_VAL
,
259 IOADDR(A_IMR_REGISTER(0,
260 R_IMR_INTERRUPT_MAP_BASE
) +
262 __raw_writeq(IMR_IP2_VAL
,
263 IOADDR(A_IMR_REGISTER(1,
264 R_IMR_INTERRUPT_MAP_BASE
) +
271 * Map the high 16 bits of the mailbox registers to IP[3], for
275 __raw_writeq(IMR_IP3_VAL
,
276 IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_MAP_BASE
) +
277 (K_INT_MBOX_0
<< 3)));
278 __raw_writeq(IMR_IP3_VAL
,
279 IOADDR(A_IMR_REGISTER(1, R_IMR_INTERRUPT_MAP_BASE
) +
280 (K_INT_MBOX_0
<< 3)));
282 /* Clear the mailboxes. The firmware may leave them dirty */
283 __raw_writeq(0xffffffffffffffffULL
,
284 IOADDR(A_IMR_REGISTER(0, R_IMR_MAILBOX_CLR_CPU
)));
285 __raw_writeq(0xffffffffffffffffULL
,
286 IOADDR(A_IMR_REGISTER(1, R_IMR_MAILBOX_CLR_CPU
)));
288 /* Mask everything except the mailbox registers for both cpus */
289 tmp
= ~((u64
) 0) ^ (((u64
) 1) << K_INT_MBOX_0
);
290 __raw_writeq(tmp
, IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_MASK
)));
291 __raw_writeq(tmp
, IOADDR(A_IMR_REGISTER(1, R_IMR_INTERRUPT_MASK
)));
294 * Note that the timer interrupts are also mapped, but this is
295 * done in sb1250_time_init(). Also, the profiling driver
296 * does its own management of IP7.
299 /* Enable necessary IPs, disable the rest */
300 change_c0_status(ST0_IM
, imask
);
303 extern void sb1250_mailbox_interrupt(void);
305 static inline void dispatch_ip2(void)
307 unsigned int cpu
= smp_processor_id();
308 unsigned long long mask
;
311 * Default...we've hit an IP[2] interrupt, which means we've got to
312 * check the 1250 interrupt registers to figure out what to do. Need
313 * to detect which CPU we're on, now that smp_affinity is supported.
315 mask
= __raw_readq(IOADDR(A_IMR_REGISTER(cpu
,
316 R_IMR_INTERRUPT_STATUS_BASE
)));
318 do_IRQ(fls64(mask
) - 1);
321 asmlinkage
void plat_irq_dispatch(void)
323 unsigned int cpu
= smp_processor_id();
324 unsigned int pending
;
327 * What a pain. We have to be really careful saving the upper 32 bits
328 * of any * register across function calls if we don't want them
329 * trashed--since were running in -o32, the calling routing never saves
330 * the full 64 bits of a register across a function call. Being the
331 * interrupt handler, we're guaranteed that interrupts are disabled
332 * during this code so we don't have to worry about random interrupts
333 * blasting the high 32 bits.
336 pending
= read_c0_cause() & read_c0_status() & ST0_IM
;
338 if (pending
& CAUSEF_IP7
) /* CPU performance counter interrupt */
339 do_IRQ(MIPS_CPU_IRQ_BASE
+ 7);
340 else if (pending
& CAUSEF_IP4
)
341 do_IRQ(K_INT_TIMER_0
+ cpu
); /* sb1250_timer_interrupt() */
344 else if (pending
& CAUSEF_IP3
)
345 sb1250_mailbox_interrupt();
348 else if (pending
& CAUSEF_IP2
)
351 spurious_interrupt();