xref: /linux/arch/sparc/kernel/leon_kernel.c (revision 50069a5851323ba5def0e414a21e234345016870)
1 /*
2  * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB
3  * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/errno.h>
8 #include <linux/mutex.h>
9 #include <linux/of.h>
10 #include <linux/of_platform.h>
11 #include <linux/interrupt.h>
12 #include <linux/of_device.h>
13 #include <linux/clocksource.h>
14 #include <linux/clockchips.h>
15 
16 #include <asm/oplib.h>
17 #include <asm/timer.h>
18 #include <asm/prom.h>
19 #include <asm/leon.h>
20 #include <asm/leon_amba.h>
21 #include <asm/traps.h>
22 #include <asm/cacheflush.h>
23 #include <asm/smp.h>
24 #include <asm/setup.h>
25 
26 #include "prom.h"
27 #include "irq.h"
28 
29 struct leon3_irqctrl_regs_map *leon3_irqctrl_regs; /* interrupt controller base address */
30 struct leon3_gptimer_regs_map *leon3_gptimer_regs; /* timer controller base address */
31 
32 int leondebug_irq_disable;
33 int leon_debug_irqout;
34 static int dummy_master_l10_counter;
35 unsigned long amba_system_id;
36 static DEFINE_SPINLOCK(leon_irq_lock);
37 
38 unsigned long leon3_gptimer_irq; /* interrupt controller irq number */
39 unsigned long leon3_gptimer_idx; /* Timer Index (0..6) within Timer Core */
40 int leon3_ticker_irq; /* Timer ticker IRQ */
41 unsigned int sparc_leon_eirq;
42 #define LEON_IMASK(cpu) (&leon3_irqctrl_regs->mask[cpu])
43 #define LEON_IACK (&leon3_irqctrl_regs->iclear)
44 #define LEON_DO_ACK_HW 1
45 
46 /* Return the last ACKed IRQ by the Extended IRQ controller. It has already
47  * been (automatically) ACKed when the CPU takes the trap.
48  */
49 static inline unsigned int leon_eirq_get(int cpu)
50 {
51 	return LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->intid[cpu]) & 0x1f;
52 }
53 
54 /* Handle one or multiple IRQs from the extended interrupt controller */
55 static void leon_handle_ext_irq(unsigned int irq, struct irq_desc *desc)
56 {
57 	unsigned int eirq;
58 	int cpu = sparc_leon3_cpuid();
59 
60 	eirq = leon_eirq_get(cpu);
61 	if ((eirq & 0x10) && irq_map[eirq]->irq) /* bit4 tells if IRQ happened */
62 		generic_handle_irq(irq_map[eirq]->irq);
63 }
64 
65 /* The extended IRQ controller has been found, this function registers it */
66 void leon_eirq_setup(unsigned int eirq)
67 {
68 	unsigned long mask, oldmask;
69 	unsigned int veirq;
70 
71 	if (eirq < 1 || eirq > 0xf) {
72 		printk(KERN_ERR "LEON EXT IRQ NUMBER BAD: %d\n", eirq);
73 		return;
74 	}
75 
76 	veirq = leon_build_device_irq(eirq, leon_handle_ext_irq, "extirq", 0);
77 
78 	/*
79 	 * Unmask the Extended IRQ, the IRQs routed through the Ext-IRQ
80 	 * controller have a mask-bit of their own, so this is safe.
81 	 */
82 	irq_link(veirq);
83 	mask = 1 << eirq;
84 	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(boot_cpu_id));
85 	LEON3_BYPASS_STORE_PA(LEON_IMASK(boot_cpu_id), (oldmask | mask));
86 	sparc_leon_eirq = eirq;
87 }
88 
89 unsigned long leon_get_irqmask(unsigned int irq)
90 {
91 	unsigned long mask;
92 
93 	if (!irq || ((irq > 0xf) && !sparc_leon_eirq)
94 	    || ((irq > 0x1f) && sparc_leon_eirq)) {
95 		printk(KERN_ERR
96 		       "leon_get_irqmask: false irq number: %d\n", irq);
97 		mask = 0;
98 	} else {
99 		mask = LEON_HARD_INT(irq);
100 	}
101 	return mask;
102 }
103 
104 #ifdef CONFIG_SMP
105 static int irq_choose_cpu(const struct cpumask *affinity)
106 {
107 	cpumask_t mask;
108 
109 	cpumask_and(&mask, cpu_online_mask, affinity);
110 	if (cpumask_equal(&mask, cpu_online_mask) || cpumask_empty(&mask))
111 		return boot_cpu_id;
112 	else
113 		return cpumask_first(&mask);
114 }
115 #else
116 #define irq_choose_cpu(affinity) boot_cpu_id
117 #endif
118 
119 static int leon_set_affinity(struct irq_data *data, const struct cpumask *dest,
120 			     bool force)
121 {
122 	unsigned long mask, oldmask, flags;
123 	int oldcpu, newcpu;
124 
125 	mask = (unsigned long)data->chip_data;
126 	oldcpu = irq_choose_cpu(data->affinity);
127 	newcpu = irq_choose_cpu(dest);
128 
129 	if (oldcpu == newcpu)
130 		goto out;
131 
132 	/* unmask on old CPU first before enabling on the selected CPU */
133 	spin_lock_irqsave(&leon_irq_lock, flags);
134 	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(oldcpu));
135 	LEON3_BYPASS_STORE_PA(LEON_IMASK(oldcpu), (oldmask & ~mask));
136 	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(newcpu));
137 	LEON3_BYPASS_STORE_PA(LEON_IMASK(newcpu), (oldmask | mask));
138 	spin_unlock_irqrestore(&leon_irq_lock, flags);
139 out:
140 	return IRQ_SET_MASK_OK;
141 }
142 
143 static void leon_unmask_irq(struct irq_data *data)
144 {
145 	unsigned long mask, oldmask, flags;
146 	int cpu;
147 
148 	mask = (unsigned long)data->chip_data;
149 	cpu = irq_choose_cpu(data->affinity);
150 	spin_lock_irqsave(&leon_irq_lock, flags);
151 	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
152 	LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask | mask));
153 	spin_unlock_irqrestore(&leon_irq_lock, flags);
154 }
155 
156 static void leon_mask_irq(struct irq_data *data)
157 {
158 	unsigned long mask, oldmask, flags;
159 	int cpu;
160 
161 	mask = (unsigned long)data->chip_data;
162 	cpu = irq_choose_cpu(data->affinity);
163 	spin_lock_irqsave(&leon_irq_lock, flags);
164 	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
165 	LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask & ~mask));
166 	spin_unlock_irqrestore(&leon_irq_lock, flags);
167 }
168 
169 static unsigned int leon_startup_irq(struct irq_data *data)
170 {
171 	irq_link(data->irq);
172 	leon_unmask_irq(data);
173 	return 0;
174 }
175 
176 static void leon_shutdown_irq(struct irq_data *data)
177 {
178 	leon_mask_irq(data);
179 	irq_unlink(data->irq);
180 }
181 
182 /* Used by external level sensitive IRQ handlers on the LEON: ACK IRQ ctrl */
183 static void leon_eoi_irq(struct irq_data *data)
184 {
185 	unsigned long mask = (unsigned long)data->chip_data;
186 
187 	if (mask & LEON_DO_ACK_HW)
188 		LEON3_BYPASS_STORE_PA(LEON_IACK, mask & ~LEON_DO_ACK_HW);
189 }
190 
191 static struct irq_chip leon_irq = {
192 	.name			= "leon",
193 	.irq_startup		= leon_startup_irq,
194 	.irq_shutdown		= leon_shutdown_irq,
195 	.irq_mask		= leon_mask_irq,
196 	.irq_unmask		= leon_unmask_irq,
197 	.irq_eoi		= leon_eoi_irq,
198 	.irq_set_affinity	= leon_set_affinity,
199 };
200 
201 /*
202  * Build a LEON IRQ for the edge triggered LEON IRQ controller:
203  *  Edge (normal) IRQ           - handle_simple_irq, ack=DONT-CARE, never ack
204  *  Level IRQ (PCI|Level-GPIO)  - handle_fasteoi_irq, ack=1, ack after ISR
205  *  Per-CPU Edge                - handle_percpu_irq, ack=0
206  */
207 unsigned int leon_build_device_irq(unsigned int real_irq,
208 				    irq_flow_handler_t flow_handler,
209 				    const char *name, int do_ack)
210 {
211 	unsigned int irq;
212 	unsigned long mask;
213 
214 	irq = 0;
215 	mask = leon_get_irqmask(real_irq);
216 	if (mask == 0)
217 		goto out;
218 
219 	irq = irq_alloc(real_irq, real_irq);
220 	if (irq == 0)
221 		goto out;
222 
223 	if (do_ack)
224 		mask |= LEON_DO_ACK_HW;
225 
226 	irq_set_chip_and_handler_name(irq, &leon_irq,
227 				      flow_handler, name);
228 	irq_set_chip_data(irq, (void *)mask);
229 
230 out:
231 	return irq;
232 }
233 
234 static unsigned int _leon_build_device_irq(struct platform_device *op,
235 					   unsigned int real_irq)
236 {
237 	return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
238 }
239 
240 void leon_update_virq_handling(unsigned int virq,
241 			      irq_flow_handler_t flow_handler,
242 			      const char *name, int do_ack)
243 {
244 	unsigned long mask = (unsigned long)irq_get_chip_data(virq);
245 
246 	mask &= ~LEON_DO_ACK_HW;
247 	if (do_ack)
248 		mask |= LEON_DO_ACK_HW;
249 
250 	irq_set_chip_and_handler_name(virq, &leon_irq,
251 				      flow_handler, name);
252 	irq_set_chip_data(virq, (void *)mask);
253 }
254 
255 static u32 leon_cycles_offset(void)
256 {
257 	u32 rld, val, off;
258 	rld = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld);
259 	val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
260 	off = rld - val;
261 	return rld - val;
262 }
263 
264 #ifdef CONFIG_SMP
265 
266 /* smp clockevent irq */
267 irqreturn_t leon_percpu_timer_ce_interrupt(int irq, void *unused)
268 {
269 	struct clock_event_device *ce;
270 	int cpu = smp_processor_id();
271 
272 	leon_clear_profile_irq(cpu);
273 
274 	ce = &per_cpu(sparc32_clockevent, cpu);
275 
276 	irq_enter();
277 	if (ce->event_handler)
278 		ce->event_handler(ce);
279 	irq_exit();
280 
281 	return IRQ_HANDLED;
282 }
283 
284 #endif /* CONFIG_SMP */
285 
286 void __init leon_init_timers(void)
287 {
288 	int irq, eirq;
289 	struct device_node *rootnp, *np, *nnp;
290 	struct property *pp;
291 	int len;
292 	int icsel;
293 	int ampopts;
294 	int err;
295 
296 	sparc_config.get_cycles_offset = leon_cycles_offset;
297 	sparc_config.cs_period = 1000000 / HZ;
298 	sparc_config.features |= FEAT_L10_CLOCKSOURCE;
299 
300 #ifndef CONFIG_SMP
301 	sparc_config.features |= FEAT_L10_CLOCKEVENT;
302 #endif
303 
304 	leondebug_irq_disable = 0;
305 	leon_debug_irqout = 0;
306 	master_l10_counter = (unsigned int *)&dummy_master_l10_counter;
307 	dummy_master_l10_counter = 0;
308 
309 	rootnp = of_find_node_by_path("/ambapp0");
310 	if (!rootnp)
311 		goto bad;
312 
313 	/* Find System ID: GRLIB build ID and optional CHIP ID */
314 	pp = of_find_property(rootnp, "systemid", &len);
315 	if (pp)
316 		amba_system_id = *(unsigned long *)pp->value;
317 
318 	/* Find IRQMP IRQ Controller Registers base adr otherwise bail out */
319 	np = of_find_node_by_name(rootnp, "GAISLER_IRQMP");
320 	if (!np) {
321 		np = of_find_node_by_name(rootnp, "01_00d");
322 		if (!np)
323 			goto bad;
324 	}
325 	pp = of_find_property(np, "reg", &len);
326 	if (!pp)
327 		goto bad;
328 	leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
329 
330 	/* Find GPTIMER Timer Registers base address otherwise bail out. */
331 	nnp = rootnp;
332 	do {
333 		np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
334 		if (!np) {
335 			np = of_find_node_by_name(nnp, "01_011");
336 			if (!np)
337 				goto bad;
338 		}
339 
340 		ampopts = 0;
341 		pp = of_find_property(np, "ampopts", &len);
342 		if (pp) {
343 			ampopts = *(int *)pp->value;
344 			if (ampopts == 0) {
345 				/* Skip this instance, resource already
346 				 * allocated by other OS */
347 				nnp = np;
348 				continue;
349 			}
350 		}
351 
352 		/* Select Timer-Instance on Timer Core. Default is zero */
353 		leon3_gptimer_idx = ampopts & 0x7;
354 
355 		pp = of_find_property(np, "reg", &len);
356 		if (pp)
357 			leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
358 						pp->value;
359 		pp = of_find_property(np, "interrupts", &len);
360 		if (pp)
361 			leon3_gptimer_irq = *(unsigned int *)pp->value;
362 	} while (0);
363 
364 	if (!(leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq))
365 		goto bad;
366 
367 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
368 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
369 				(((1000000 / HZ) - 1)));
370 	LEON3_BYPASS_STORE_PA(
371 			&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
372 
373 #ifdef CONFIG_SMP
374 	leon3_ticker_irq = leon3_gptimer_irq + 1 + leon3_gptimer_idx;
375 
376 	if (!(LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config) &
377 	      (1<<LEON3_GPTIMER_SEPIRQ))) {
378 		printk(KERN_ERR "timer not configured with separate irqs\n");
379 		BUG();
380 	}
381 
382 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].val,
383 				0);
384 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].rld,
385 				(((1000000/HZ) - 1)));
386 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].ctrl,
387 				0);
388 #endif
389 
390 	/*
391 	 * The IRQ controller may (if implemented) consist of multiple
392 	 * IRQ controllers, each mapped on a 4Kb boundary.
393 	 * Each CPU may be routed to different IRQCTRLs, however
394 	 * we assume that all CPUs (in SMP system) is routed to the
395 	 * same IRQ Controller, and for non-SMP only one IRQCTRL is
396 	 * accessed anyway.
397 	 * In AMP systems, Linux must run on CPU0 for the time being.
398 	 */
399 	icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[boot_cpu_id/8]);
400 	icsel = (icsel >> ((7 - (boot_cpu_id&0x7)) * 4)) & 0xf;
401 	leon3_irqctrl_regs += icsel;
402 
403 	/* Mask all IRQs on boot-cpu IRQ controller */
404 	LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[boot_cpu_id], 0);
405 
406 	/* Probe extended IRQ controller */
407 	eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
408 		>> 16) & 0xf;
409 	if (eirq != 0)
410 		leon_eirq_setup(eirq);
411 
412 	irq = _leon_build_device_irq(NULL, leon3_gptimer_irq+leon3_gptimer_idx);
413 	err = request_irq(irq, timer_interrupt, IRQF_TIMER, "timer", NULL);
414 	if (err) {
415 		printk(KERN_ERR "unable to attach timer IRQ%d\n", irq);
416 		prom_halt();
417 	}
418 
419 #ifdef CONFIG_SMP
420 	{
421 		unsigned long flags;
422 
423 		/*
424 		 * In SMP, sun4m adds a IPI handler to IRQ trap handler that
425 		 * LEON never must take, sun4d and LEON overwrites the branch
426 		 * with a NOP.
427 		 */
428 		local_irq_save(flags);
429 		patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
430 		local_ops->cache_all();
431 		local_irq_restore(flags);
432 	}
433 #endif
434 
435 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
436 			      LEON3_GPTIMER_EN |
437 			      LEON3_GPTIMER_RL |
438 			      LEON3_GPTIMER_LD |
439 			      LEON3_GPTIMER_IRQEN);
440 
441 #ifdef CONFIG_SMP
442 	/* Install per-cpu IRQ handler for broadcasted ticker */
443 	irq = leon_build_device_irq(leon3_ticker_irq, handle_percpu_irq,
444 				    "per-cpu", 0);
445 	err = request_irq(irq, leon_percpu_timer_ce_interrupt,
446 			  IRQF_PERCPU | IRQF_TIMER, "ticker",
447 			  NULL);
448 	if (err) {
449 		printk(KERN_ERR "unable to attach ticker IRQ%d\n", irq);
450 		prom_halt();
451 	}
452 
453 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].ctrl,
454 			      LEON3_GPTIMER_EN |
455 			      LEON3_GPTIMER_RL |
456 			      LEON3_GPTIMER_LD |
457 			      LEON3_GPTIMER_IRQEN);
458 #endif
459 	return;
460 bad:
461 	printk(KERN_ERR "No Timer/irqctrl found\n");
462 	BUG();
463 	return;
464 }
465 
466 static void leon_clear_clock_irq(void)
467 {
468 }
469 
470 static void leon_load_profile_irq(int cpu, unsigned int limit)
471 {
472 }
473 
474 void __init leon_trans_init(struct device_node *dp)
475 {
476 	if (strcmp(dp->type, "cpu") == 0 && strcmp(dp->name, "<NULL>") == 0) {
477 		struct property *p;
478 		p = of_find_property(dp, "mid", (void *)0);
479 		if (p) {
480 			int mid;
481 			dp->name = prom_early_alloc(5 + 1);
482 			memcpy(&mid, p->value, p->length);
483 			sprintf((char *)dp->name, "cpu%.2d", mid);
484 		}
485 	}
486 }
487 
488 void __initdata (*prom_amba_init)(struct device_node *dp, struct device_node ***nextp) = 0;
489 
490 void __init leon_node_init(struct device_node *dp, struct device_node ***nextp)
491 {
492 	if (prom_amba_init &&
493 	    strcmp(dp->type, "ambapp") == 0 &&
494 	    strcmp(dp->name, "ambapp0") == 0) {
495 		prom_amba_init(dp, nextp);
496 	}
497 }
498 
499 #ifdef CONFIG_SMP
500 void leon_clear_profile_irq(int cpu)
501 {
502 }
503 
504 void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
505 {
506 	unsigned long mask, flags, *addr;
507 	mask = leon_get_irqmask(irq_nr);
508 	spin_lock_irqsave(&leon_irq_lock, flags);
509 	addr = (unsigned long *)LEON_IMASK(cpu);
510 	LEON3_BYPASS_STORE_PA(addr, (LEON3_BYPASS_LOAD_PA(addr) | mask));
511 	spin_unlock_irqrestore(&leon_irq_lock, flags);
512 }
513 
514 #endif
515 
516 void __init leon_init_IRQ(void)
517 {
518 	sparc_config.init_timers      = leon_init_timers;
519 	sparc_config.build_device_irq = _leon_build_device_irq;
520 	sparc_config.clock_rate       = 1000000;
521 	sparc_config.clear_clock_irq  = leon_clear_clock_irq;
522 	sparc_config.load_profile_irq = leon_load_profile_irq;
523 }
524 
525 void __init leon_init(void)
526 {
527 	of_pdt_build_more = &leon_node_init;
528 }
529