diff options
author | Yi Li <yi.li@analog.com> | 2009-01-07 10:14:39 -0500 |
---|---|---|
committer | Bryan Wu <cooloney@kernel.org> | 2009-01-07 10:14:39 -0500 |
commit | 6a01f230339321292cf065551f8cf55361052461 (patch) | |
tree | 7ac2ac8fc9f05a7315ef6a7f6f0a387433c62c14 /arch/blackfin/kernel/ipipe.c | |
parent | 5105432a3201e3f0e6c219cd0a74feee1e5e262b (diff) |
Blackfin arch: merge adeos blackfin part to arch/blackfin/
[Mike Frysinger <vapier.adi@gmail.com>:
- handle bf531/bf532/bf534/bf536 variants in ipipe.h
- cleanup IPIPE logic for bfin_set_irq_handler()
- cleanup ipipe asm code a bit and add missing ENDPROC()
- simplify IPIPE code in trap_c
- unify some of the IPIPE code and fix style
- simplify DO_IRQ_L1 handling with ipipe code
- revert IRQ_SW_INT# addition from ipipe merge
- remove duplicate get_{c,s}clk() prototypes
]
Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Diffstat (limited to 'arch/blackfin/kernel/ipipe.c')
-rw-r--r-- | arch/blackfin/kernel/ipipe.c | 428 |
1 files changed, 428 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/ipipe.c b/arch/blackfin/kernel/ipipe.c new file mode 100644 index 000000000000..339be5a3ae6a --- /dev/null +++ b/arch/blackfin/kernel/ipipe.c | |||
@@ -0,0 +1,428 @@ | |||
1 | /* -*- linux-c -*- | ||
2 | * linux/arch/blackfin/kernel/ipipe.c | ||
3 | * | ||
4 | * Copyright (C) 2005-2007 Philippe Gerum. | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or modify | ||
7 | * it under the terms of the GNU General Public License as published by | ||
8 | * the Free Software Foundation, Inc., 675 Mass Ave, Cambridge MA 02139, | ||
9 | * USA; either version 2 of the License, or (at your option) any later | ||
10 | * version. | ||
11 | * | ||
12 | * This program is distributed in the hope that it will be useful, | ||
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
15 | * GNU General Public License for more details. | ||
16 | * | ||
17 | * You should have received a copy of the GNU General Public License | ||
18 | * along with this program; if not, write to the Free Software | ||
19 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | ||
20 | * | ||
21 | * Architecture-dependent I-pipe support for the Blackfin. | ||
22 | */ | ||
23 | |||
24 | #include <linux/kernel.h> | ||
25 | #include <linux/sched.h> | ||
26 | #include <linux/module.h> | ||
27 | #include <linux/interrupt.h> | ||
28 | #include <linux/percpu.h> | ||
29 | #include <linux/bitops.h> | ||
30 | #include <linux/slab.h> | ||
31 | #include <linux/errno.h> | ||
32 | #include <linux/kthread.h> | ||
33 | #include <asm/unistd.h> | ||
34 | #include <asm/system.h> | ||
35 | #include <asm/atomic.h> | ||
36 | #include <asm/io.h> | ||
37 | |||
38 | static int create_irq_threads; | ||
39 | |||
40 | DEFINE_PER_CPU(struct pt_regs, __ipipe_tick_regs); | ||
41 | |||
42 | static DEFINE_PER_CPU(unsigned long, pending_irqthread_mask); | ||
43 | |||
44 | static DEFINE_PER_CPU(int [IVG13 + 1], pending_irq_count); | ||
45 | |||
46 | asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs); | ||
47 | |||
48 | static void __ipipe_no_irqtail(void); | ||
49 | |||
50 | unsigned long __ipipe_irq_tail_hook = (unsigned long)&__ipipe_no_irqtail; | ||
51 | EXPORT_SYMBOL(__ipipe_irq_tail_hook); | ||
52 | |||
53 | unsigned long __ipipe_core_clock; | ||
54 | EXPORT_SYMBOL(__ipipe_core_clock); | ||
55 | |||
56 | unsigned long __ipipe_freq_scale; | ||
57 | EXPORT_SYMBOL(__ipipe_freq_scale); | ||
58 | |||
59 | atomic_t __ipipe_irq_lvdepth[IVG15 + 1]; | ||
60 | |||
61 | unsigned long __ipipe_irq_lvmask = __all_masked_irq_flags; | ||
62 | EXPORT_SYMBOL(__ipipe_irq_lvmask); | ||
63 | |||
64 | static void __ipipe_ack_irq(unsigned irq, struct irq_desc *desc) | ||
65 | { | ||
66 | desc->ipipe_ack(irq, desc); | ||
67 | } | ||
68 | |||
69 | /* | ||
70 | * __ipipe_enable_pipeline() -- We are running on the boot CPU, hw | ||
71 | * interrupts are off, and secondary CPUs are still lost in space. | ||
72 | */ | ||
73 | void __ipipe_enable_pipeline(void) | ||
74 | { | ||
75 | unsigned irq; | ||
76 | |||
77 | __ipipe_core_clock = get_cclk(); /* Fetch this once. */ | ||
78 | __ipipe_freq_scale = 1000000000UL / __ipipe_core_clock; | ||
79 | |||
80 | for (irq = 0; irq < NR_IRQS; ++irq) | ||
81 | ipipe_virtualize_irq(ipipe_root_domain, | ||
82 | irq, | ||
83 | (ipipe_irq_handler_t)&asm_do_IRQ, | ||
84 | NULL, | ||
85 | &__ipipe_ack_irq, | ||
86 | IPIPE_HANDLE_MASK | IPIPE_PASS_MASK); | ||
87 | } | ||
88 | |||
89 | /* | ||
90 | * __ipipe_handle_irq() -- IPIPE's generic IRQ handler. An optimistic | ||
91 | * interrupt protection log is maintained here for each domain. Hw | ||
92 | * interrupts are masked on entry. | ||
93 | */ | ||
94 | void __ipipe_handle_irq(unsigned irq, struct pt_regs *regs) | ||
95 | { | ||
96 | struct ipipe_domain *this_domain, *next_domain; | ||
97 | struct list_head *head, *pos; | ||
98 | int m_ack, s = -1; | ||
99 | |||
100 | /* | ||
101 | * Software-triggered IRQs do not need any ack. The contents | ||
102 | * of the register frame should only be used when processing | ||
103 | * the timer interrupt, but not for handling any other | ||
104 | * interrupt. | ||
105 | */ | ||
106 | m_ack = (regs == NULL || irq == IRQ_SYSTMR || irq == IRQ_CORETMR); | ||
107 | |||
108 | this_domain = ipipe_current_domain; | ||
109 | |||
110 | if (unlikely(test_bit(IPIPE_STICKY_FLAG, &this_domain->irqs[irq].control))) | ||
111 | head = &this_domain->p_link; | ||
112 | else { | ||
113 | head = __ipipe_pipeline.next; | ||
114 | next_domain = list_entry(head, struct ipipe_domain, p_link); | ||
115 | if (likely(test_bit(IPIPE_WIRED_FLAG, &next_domain->irqs[irq].control))) { | ||
116 | if (!m_ack && next_domain->irqs[irq].acknowledge != NULL) | ||
117 | next_domain->irqs[irq].acknowledge(irq, irq_desc + irq); | ||
118 | if (test_bit(IPIPE_ROOTLOCK_FLAG, &ipipe_root_domain->flags)) | ||
119 | s = __test_and_set_bit(IPIPE_STALL_FLAG, | ||
120 | &ipipe_root_cpudom_var(status)); | ||
121 | __ipipe_dispatch_wired(next_domain, irq); | ||
122 | goto finalize; | ||
123 | return; | ||
124 | } | ||
125 | } | ||
126 | |||
127 | /* Ack the interrupt. */ | ||
128 | |||
129 | pos = head; | ||
130 | |||
131 | while (pos != &__ipipe_pipeline) { | ||
132 | next_domain = list_entry(pos, struct ipipe_domain, p_link); | ||
133 | /* | ||
134 | * For each domain handling the incoming IRQ, mark it | ||
135 | * as pending in its log. | ||
136 | */ | ||
137 | if (test_bit(IPIPE_HANDLE_FLAG, &next_domain->irqs[irq].control)) { | ||
138 | /* | ||
139 | * Domains that handle this IRQ are polled for | ||
140 | * acknowledging it by decreasing priority | ||
141 | * order. The interrupt must be made pending | ||
142 | * _first_ in the domain's status flags before | ||
143 | * the PIC is unlocked. | ||
144 | */ | ||
145 | __ipipe_set_irq_pending(next_domain, irq); | ||
146 | |||
147 | if (!m_ack && next_domain->irqs[irq].acknowledge != NULL) { | ||
148 | next_domain->irqs[irq].acknowledge(irq, irq_desc + irq); | ||
149 | m_ack = 1; | ||
150 | } | ||
151 | } | ||
152 | |||
153 | /* | ||
154 | * If the domain does not want the IRQ to be passed | ||
155 | * down the interrupt pipe, exit the loop now. | ||
156 | */ | ||
157 | if (!test_bit(IPIPE_PASS_FLAG, &next_domain->irqs[irq].control)) | ||
158 | break; | ||
159 | |||
160 | pos = next_domain->p_link.next; | ||
161 | } | ||
162 | |||
163 | /* | ||
164 | * Now walk the pipeline, yielding control to the highest | ||
165 | * priority domain that has pending interrupt(s) or | ||
166 | * immediately to the current domain if the interrupt has been | ||
167 | * marked as 'sticky'. This search does not go beyond the | ||
168 | * current domain in the pipeline. We also enforce the | ||
169 | * additional root stage lock (blackfin-specific). */ | ||
170 | |||
171 | if (test_bit(IPIPE_ROOTLOCK_FLAG, &ipipe_root_domain->flags)) | ||
172 | s = __test_and_set_bit(IPIPE_STALL_FLAG, | ||
173 | &ipipe_root_cpudom_var(status)); | ||
174 | finalize: | ||
175 | |||
176 | __ipipe_walk_pipeline(head); | ||
177 | |||
178 | if (!s) | ||
179 | __clear_bit(IPIPE_STALL_FLAG, | ||
180 | &ipipe_root_cpudom_var(status)); | ||
181 | } | ||
182 | |||
183 | int __ipipe_check_root(void) | ||
184 | { | ||
185 | return ipipe_root_domain_p; | ||
186 | } | ||
187 | |||
188 | void __ipipe_enable_irqdesc(struct ipipe_domain *ipd, unsigned irq) | ||
189 | { | ||
190 | struct irq_desc *desc = irq_desc + irq; | ||
191 | int prio = desc->ic_prio; | ||
192 | |||
193 | desc->depth = 0; | ||
194 | if (ipd != &ipipe_root && | ||
195 | atomic_inc_return(&__ipipe_irq_lvdepth[prio]) == 1) | ||
196 | __set_bit(prio, &__ipipe_irq_lvmask); | ||
197 | } | ||
198 | EXPORT_SYMBOL(__ipipe_enable_irqdesc); | ||
199 | |||
200 | void __ipipe_disable_irqdesc(struct ipipe_domain *ipd, unsigned irq) | ||
201 | { | ||
202 | struct irq_desc *desc = irq_desc + irq; | ||
203 | int prio = desc->ic_prio; | ||
204 | |||
205 | if (ipd != &ipipe_root && | ||
206 | atomic_dec_and_test(&__ipipe_irq_lvdepth[prio])) | ||
207 | __clear_bit(prio, &__ipipe_irq_lvmask); | ||
208 | } | ||
209 | EXPORT_SYMBOL(__ipipe_disable_irqdesc); | ||
210 | |||
211 | void __ipipe_stall_root_raw(void) | ||
212 | { | ||
213 | /* | ||
214 | * This code is called by the ins{bwl} routines (see | ||
215 | * arch/blackfin/lib/ins.S), which are heavily used by the | ||
216 | * network stack. It masks all interrupts but those handled by | ||
217 | * non-root domains, so that we keep decent network transfer | ||
218 | * rates for Linux without inducing pathological jitter for | ||
219 | * the real-time domain. | ||
220 | */ | ||
221 | __asm__ __volatile__ ("sti %0;" : : "d"(__ipipe_irq_lvmask)); | ||
222 | |||
223 | __set_bit(IPIPE_STALL_FLAG, | ||
224 | &ipipe_root_cpudom_var(status)); | ||
225 | } | ||
226 | |||
227 | void __ipipe_unstall_root_raw(void) | ||
228 | { | ||
229 | __clear_bit(IPIPE_STALL_FLAG, | ||
230 | &ipipe_root_cpudom_var(status)); | ||
231 | |||
232 | __asm__ __volatile__ ("sti %0;" : : "d"(bfin_irq_flags)); | ||
233 | } | ||
234 | |||
235 | int __ipipe_syscall_root(struct pt_regs *regs) | ||
236 | { | ||
237 | unsigned long flags; | ||
238 | |||
239 | /* We need to run the IRQ tail hook whenever we don't | ||
240 | * propagate a syscall to higher domains, because we know that | ||
241 | * important operations might be pending there (e.g. Xenomai | ||
242 | * deferred rescheduling). */ | ||
243 | |||
244 | if (!__ipipe_syscall_watched_p(current, regs->orig_p0)) { | ||
245 | void (*hook)(void) = (void (*)(void))__ipipe_irq_tail_hook; | ||
246 | hook(); | ||
247 | return 0; | ||
248 | } | ||
249 | |||
250 | /* | ||
251 | * This routine either returns: | ||
252 | * 0 -- if the syscall is to be passed to Linux; | ||
253 | * 1 -- if the syscall should not be passed to Linux, and no | ||
254 | * tail work should be performed; | ||
255 | * -1 -- if the syscall should not be passed to Linux but the | ||
256 | * tail work has to be performed (for handling signals etc). | ||
257 | */ | ||
258 | |||
259 | if (__ipipe_event_monitored_p(IPIPE_EVENT_SYSCALL) && | ||
260 | __ipipe_dispatch_event(IPIPE_EVENT_SYSCALL, regs) > 0) { | ||
261 | if (ipipe_root_domain_p && !in_atomic()) { | ||
262 | /* | ||
263 | * Sync pending VIRQs before _TIF_NEED_RESCHED | ||
264 | * is tested. | ||
265 | */ | ||
266 | local_irq_save_hw(flags); | ||
267 | if ((ipipe_root_cpudom_var(irqpend_himask) & IPIPE_IRQMASK_VIRT) != 0) | ||
268 | __ipipe_sync_pipeline(IPIPE_IRQMASK_VIRT); | ||
269 | local_irq_restore_hw(flags); | ||
270 | return -1; | ||
271 | } | ||
272 | return 1; | ||
273 | } | ||
274 | |||
275 | return 0; | ||
276 | } | ||
277 | |||
278 | unsigned long ipipe_critical_enter(void (*syncfn) (void)) | ||
279 | { | ||
280 | unsigned long flags; | ||
281 | |||
282 | local_irq_save_hw(flags); | ||
283 | |||
284 | return flags; | ||
285 | } | ||
286 | |||
287 | void ipipe_critical_exit(unsigned long flags) | ||
288 | { | ||
289 | local_irq_restore_hw(flags); | ||
290 | } | ||
291 | |||
292 | static void __ipipe_no_irqtail(void) | ||
293 | { | ||
294 | } | ||
295 | |||
296 | int ipipe_get_sysinfo(struct ipipe_sysinfo *info) | ||
297 | { | ||
298 | info->ncpus = num_online_cpus(); | ||
299 | info->cpufreq = ipipe_cpu_freq(); | ||
300 | info->archdep.tmirq = IPIPE_TIMER_IRQ; | ||
301 | info->archdep.tmfreq = info->cpufreq; | ||
302 | |||
303 | return 0; | ||
304 | } | ||
305 | |||
306 | /* | ||
307 | * ipipe_trigger_irq() -- Push the interrupt at front of the pipeline | ||
308 | * just like if it has been actually received from a hw source. Also | ||
309 | * works for virtual interrupts. | ||
310 | */ | ||
311 | int ipipe_trigger_irq(unsigned irq) | ||
312 | { | ||
313 | unsigned long flags; | ||
314 | |||
315 | if (irq >= IPIPE_NR_IRQS || | ||
316 | (ipipe_virtual_irq_p(irq) | ||
317 | && !test_bit(irq - IPIPE_VIRQ_BASE, &__ipipe_virtual_irq_map))) | ||
318 | return -EINVAL; | ||
319 | |||
320 | local_irq_save_hw(flags); | ||
321 | |||
322 | __ipipe_handle_irq(irq, NULL); | ||
323 | |||
324 | local_irq_restore_hw(flags); | ||
325 | |||
326 | return 1; | ||
327 | } | ||
328 | |||
329 | /* Move Linux IRQ to threads. */ | ||
330 | |||
331 | static int do_irqd(void *__desc) | ||
332 | { | ||
333 | struct irq_desc *desc = __desc; | ||
334 | unsigned irq = desc - irq_desc; | ||
335 | int thrprio = desc->thr_prio; | ||
336 | int thrmask = 1 << thrprio; | ||
337 | int cpu = smp_processor_id(); | ||
338 | cpumask_t cpumask; | ||
339 | |||
340 | sigfillset(¤t->blocked); | ||
341 | current->flags |= PF_NOFREEZE; | ||
342 | cpumask = cpumask_of_cpu(cpu); | ||
343 | set_cpus_allowed(current, cpumask); | ||
344 | ipipe_setscheduler_root(current, SCHED_FIFO, 50 + thrprio); | ||
345 | |||
346 | while (!kthread_should_stop()) { | ||
347 | local_irq_disable(); | ||
348 | if (!(desc->status & IRQ_SCHEDULED)) { | ||
349 | set_current_state(TASK_INTERRUPTIBLE); | ||
350 | resched: | ||
351 | local_irq_enable(); | ||
352 | schedule(); | ||
353 | local_irq_disable(); | ||
354 | } | ||
355 | __set_current_state(TASK_RUNNING); | ||
356 | /* | ||
357 | * If higher priority interrupt servers are ready to | ||
358 | * run, reschedule immediately. We need this for the | ||
359 | * GPIO demux IRQ handler to unmask the interrupt line | ||
360 | * _last_, after all GPIO IRQs have run. | ||
361 | */ | ||
362 | if (per_cpu(pending_irqthread_mask, cpu) & ~(thrmask|(thrmask-1))) | ||
363 | goto resched; | ||
364 | if (--per_cpu(pending_irq_count[thrprio], cpu) == 0) | ||
365 | per_cpu(pending_irqthread_mask, cpu) &= ~thrmask; | ||
366 | desc->status &= ~IRQ_SCHEDULED; | ||
367 | desc->thr_handler(irq, &__raw_get_cpu_var(__ipipe_tick_regs)); | ||
368 | local_irq_enable(); | ||
369 | } | ||
370 | __set_current_state(TASK_RUNNING); | ||
371 | return 0; | ||
372 | } | ||
373 | |||
374 | static void kick_irqd(unsigned irq, void *cookie) | ||
375 | { | ||
376 | struct irq_desc *desc = irq_desc + irq; | ||
377 | int thrprio = desc->thr_prio; | ||
378 | int thrmask = 1 << thrprio; | ||
379 | int cpu = smp_processor_id(); | ||
380 | |||
381 | if (!(desc->status & IRQ_SCHEDULED)) { | ||
382 | desc->status |= IRQ_SCHEDULED; | ||
383 | per_cpu(pending_irqthread_mask, cpu) |= thrmask; | ||
384 | ++per_cpu(pending_irq_count[thrprio], cpu); | ||
385 | wake_up_process(desc->thread); | ||
386 | } | ||
387 | } | ||
388 | |||
389 | int ipipe_start_irq_thread(unsigned irq, struct irq_desc *desc) | ||
390 | { | ||
391 | if (desc->thread || !create_irq_threads) | ||
392 | return 0; | ||
393 | |||
394 | desc->thread = kthread_create(do_irqd, desc, "IRQ %d", irq); | ||
395 | if (desc->thread == NULL) { | ||
396 | printk(KERN_ERR "irqd: could not create IRQ thread %d!\n", irq); | ||
397 | return -ENOMEM; | ||
398 | } | ||
399 | |||
400 | wake_up_process(desc->thread); | ||
401 | |||
402 | desc->thr_handler = ipipe_root_domain->irqs[irq].handler; | ||
403 | ipipe_root_domain->irqs[irq].handler = &kick_irqd; | ||
404 | |||
405 | return 0; | ||
406 | } | ||
407 | |||
408 | void __init ipipe_init_irq_threads(void) | ||
409 | { | ||
410 | unsigned irq; | ||
411 | struct irq_desc *desc; | ||
412 | |||
413 | create_irq_threads = 1; | ||
414 | |||
415 | for (irq = 0; irq < NR_IRQS; irq++) { | ||
416 | desc = irq_desc + irq; | ||
417 | if (desc->action != NULL || | ||
418 | (desc->status & IRQ_NOREQUEST) != 0) | ||
419 | ipipe_start_irq_thread(irq, desc); | ||
420 | } | ||
421 | } | ||
422 | |||
423 | EXPORT_SYMBOL(show_stack); | ||
424 | |||
425 | #ifdef CONFIG_IPIPE_TRACE_MCOUNT | ||
426 | void notrace _mcount(void); | ||
427 | EXPORT_SYMBOL(_mcount); | ||
428 | #endif /* CONFIG_IPIPE_TRACE_MCOUNT */ | ||