xref: /openbmc/linux/arch/sparc/kernel/leon_kernel.c (revision 81d67439)
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/module.h>
8 #include <linux/errno.h>
9 #include <linux/mutex.h>
10 #include <linux/of.h>
11 #include <linux/of_platform.h>
12 #include <linux/interrupt.h>
13 #include <linux/of_device.h>
14 
15 #include <asm/oplib.h>
16 #include <asm/timer.h>
17 #include <asm/prom.h>
18 #include <asm/leon.h>
19 #include <asm/leon_amba.h>
20 #include <asm/traps.h>
21 #include <asm/cacheflush.h>
22 #include <asm/smp.h>
23 #include <asm/setup.h>
24 
25 #include "prom.h"
26 #include "irq.h"
27 
28 struct leon3_irqctrl_regs_map *leon3_irqctrl_regs; /* interrupt controller base address */
29 struct leon3_gptimer_regs_map *leon3_gptimer_regs; /* timer controller base address */
30 
31 int leondebug_irq_disable;
32 int leon_debug_irqout;
33 static int dummy_master_l10_counter;
34 unsigned long amba_system_id;
35 static DEFINE_SPINLOCK(leon_irq_lock);
36 
37 unsigned long leon3_gptimer_irq; /* interrupt controller irq number */
38 unsigned long leon3_gptimer_idx; /* Timer Index (0..6) within Timer Core */
39 int leon3_ticker_irq; /* Timer ticker IRQ */
40 unsigned int sparc_leon_eirq;
41 #define LEON_IMASK(cpu) (&leon3_irqctrl_regs->mask[cpu])
42 #define LEON_IACK (&leon3_irqctrl_regs->iclear)
43 #define LEON_DO_ACK_HW 1
44 
45 /* Return the last ACKed IRQ by the Extended IRQ controller. It has already
46  * been (automatically) ACKed when the CPU takes the trap.
47  */
48 static inline unsigned int leon_eirq_get(int cpu)
49 {
50 	return LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->intid[cpu]) & 0x1f;
51 }
52 
53 /* Handle one or multiple IRQs from the extended interrupt controller */
54 static void leon_handle_ext_irq(unsigned int irq, struct irq_desc *desc)
55 {
56 	unsigned int eirq;
57 	int cpu = sparc_leon3_cpuid();
58 
59 	eirq = leon_eirq_get(cpu);
60 	if ((eirq & 0x10) && irq_map[eirq]->irq) /* bit4 tells if IRQ happened */
61 		generic_handle_irq(irq_map[eirq]->irq);
62 }
63 
64 /* The extended IRQ controller has been found, this function registers it */
65 void leon_eirq_setup(unsigned int eirq)
66 {
67 	unsigned long mask, oldmask;
68 	unsigned int veirq;
69 
70 	if (eirq < 1 || eirq > 0xf) {
71 		printk(KERN_ERR "LEON EXT IRQ NUMBER BAD: %d\n", eirq);
72 		return;
73 	}
74 
75 	veirq = leon_build_device_irq(eirq, leon_handle_ext_irq, "extirq", 0);
76 
77 	/*
78 	 * Unmask the Extended IRQ, the IRQs routed through the Ext-IRQ
79 	 * controller have a mask-bit of their own, so this is safe.
80 	 */
81 	irq_link(veirq);
82 	mask = 1 << eirq;
83 	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(boot_cpu_id));
84 	LEON3_BYPASS_STORE_PA(LEON_IMASK(boot_cpu_id), (oldmask | mask));
85 	sparc_leon_eirq = eirq;
86 }
87 
88 static inline unsigned long get_irqmask(unsigned int irq)
89 {
90 	unsigned long mask;
91 
92 	if (!irq || ((irq > 0xf) && !sparc_leon_eirq)
93 	    || ((irq > 0x1f) && sparc_leon_eirq)) {
94 		printk(KERN_ERR
95 		       "leon_get_irqmask: false irq number: %d\n", irq);
96 		mask = 0;
97 	} else {
98 		mask = LEON_HARD_INT(irq);
99 	}
100 	return mask;
101 }
102 
103 #ifdef CONFIG_SMP
104 static int irq_choose_cpu(const struct cpumask *affinity)
105 {
106 	cpumask_t mask;
107 
108 	cpus_and(mask, cpu_online_map, *affinity);
109 	if (cpus_equal(mask, cpu_online_map) || cpus_empty(mask))
110 		return boot_cpu_id;
111 	else
112 		return first_cpu(mask);
113 }
114 #else
115 #define irq_choose_cpu(affinity) boot_cpu_id
116 #endif
117 
118 static int leon_set_affinity(struct irq_data *data, const struct cpumask *dest,
119 			     bool force)
120 {
121 	unsigned long mask, oldmask, flags;
122 	int oldcpu, newcpu;
123 
124 	mask = (unsigned long)data->chip_data;
125 	oldcpu = irq_choose_cpu(data->affinity);
126 	newcpu = irq_choose_cpu(dest);
127 
128 	if (oldcpu == newcpu)
129 		goto out;
130 
131 	/* unmask on old CPU first before enabling on the selected CPU */
132 	spin_lock_irqsave(&leon_irq_lock, flags);
133 	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(oldcpu));
134 	LEON3_BYPASS_STORE_PA(LEON_IMASK(oldcpu), (oldmask & ~mask));
135 	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(newcpu));
136 	LEON3_BYPASS_STORE_PA(LEON_IMASK(newcpu), (oldmask | mask));
137 	spin_unlock_irqrestore(&leon_irq_lock, flags);
138 out:
139 	return IRQ_SET_MASK_OK;
140 }
141 
142 static void leon_unmask_irq(struct irq_data *data)
143 {
144 	unsigned long mask, oldmask, flags;
145 	int cpu;
146 
147 	mask = (unsigned long)data->chip_data;
148 	cpu = irq_choose_cpu(data->affinity);
149 	spin_lock_irqsave(&leon_irq_lock, flags);
150 	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
151 	LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask | mask));
152 	spin_unlock_irqrestore(&leon_irq_lock, flags);
153 }
154 
155 static void leon_mask_irq(struct irq_data *data)
156 {
157 	unsigned long mask, oldmask, flags;
158 	int cpu;
159 
160 	mask = (unsigned long)data->chip_data;
161 	cpu = irq_choose_cpu(data->affinity);
162 	spin_lock_irqsave(&leon_irq_lock, flags);
163 	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
164 	LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask & ~mask));
165 	spin_unlock_irqrestore(&leon_irq_lock, flags);
166 }
167 
168 static unsigned int leon_startup_irq(struct irq_data *data)
169 {
170 	irq_link(data->irq);
171 	leon_unmask_irq(data);
172 	return 0;
173 }
174 
175 static void leon_shutdown_irq(struct irq_data *data)
176 {
177 	leon_mask_irq(data);
178 	irq_unlink(data->irq);
179 }
180 
181 /* Used by external level sensitive IRQ handlers on the LEON: ACK IRQ ctrl */
182 static void leon_eoi_irq(struct irq_data *data)
183 {
184 	unsigned long mask = (unsigned long)data->chip_data;
185 
186 	if (mask & LEON_DO_ACK_HW)
187 		LEON3_BYPASS_STORE_PA(LEON_IACK, mask & ~LEON_DO_ACK_HW);
188 }
189 
190 static struct irq_chip leon_irq = {
191 	.name			= "leon",
192 	.irq_startup		= leon_startup_irq,
193 	.irq_shutdown		= leon_shutdown_irq,
194 	.irq_mask		= leon_mask_irq,
195 	.irq_unmask		= leon_unmask_irq,
196 	.irq_eoi		= leon_eoi_irq,
197 	.irq_set_affinity	= leon_set_affinity,
198 };
199 
200 /*
201  * Build a LEON IRQ for the edge triggered LEON IRQ controller:
202  *  Edge (normal) IRQ           - handle_simple_irq, ack=DONT-CARE, never ack
203  *  Level IRQ (PCI|Level-GPIO)  - handle_fasteoi_irq, ack=1, ack after ISR
204  *  Per-CPU Edge                - handle_percpu_irq, ack=0
205  */
206 unsigned int leon_build_device_irq(unsigned int real_irq,
207 				    irq_flow_handler_t flow_handler,
208 				    const char *name, int do_ack)
209 {
210 	unsigned int irq;
211 	unsigned long mask;
212 
213 	irq = 0;
214 	mask = get_irqmask(real_irq);
215 	if (mask == 0)
216 		goto out;
217 
218 	irq = irq_alloc(real_irq, real_irq);
219 	if (irq == 0)
220 		goto out;
221 
222 	if (do_ack)
223 		mask |= LEON_DO_ACK_HW;
224 
225 	irq_set_chip_and_handler_name(irq, &leon_irq,
226 				      flow_handler, name);
227 	irq_set_chip_data(irq, (void *)mask);
228 
229 out:
230 	return irq;
231 }
232 
233 static unsigned int _leon_build_device_irq(struct platform_device *op,
234 					   unsigned int real_irq)
235 {
236 	return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
237 }
238 
239 void leon_update_virq_handling(unsigned int virq,
240 			      irq_flow_handler_t flow_handler,
241 			      const char *name, int do_ack)
242 {
243 	unsigned long mask = (unsigned long)irq_get_chip_data(virq);
244 
245 	mask &= ~LEON_DO_ACK_HW;
246 	if (do_ack)
247 		mask |= LEON_DO_ACK_HW;
248 
249 	irq_set_chip_and_handler_name(virq, &leon_irq,
250 				      flow_handler, name);
251 	irq_set_chip_data(virq, (void *)mask);
252 }
253 
254 void __init leon_init_timers(irq_handler_t counter_fn)
255 {
256 	int irq, eirq;
257 	struct device_node *rootnp, *np, *nnp;
258 	struct property *pp;
259 	int len;
260 	int icsel;
261 	int ampopts;
262 	int err;
263 
264 	leondebug_irq_disable = 0;
265 	leon_debug_irqout = 0;
266 	master_l10_counter = (unsigned int *)&dummy_master_l10_counter;
267 	dummy_master_l10_counter = 0;
268 
269 	rootnp = of_find_node_by_path("/ambapp0");
270 	if (!rootnp)
271 		goto bad;
272 
273 	/* Find System ID: GRLIB build ID and optional CHIP ID */
274 	pp = of_find_property(rootnp, "systemid", &len);
275 	if (pp)
276 		amba_system_id = *(unsigned long *)pp->value;
277 
278 	/* Find IRQMP IRQ Controller Registers base adr otherwise bail out */
279 	np = of_find_node_by_name(rootnp, "GAISLER_IRQMP");
280 	if (!np) {
281 		np = of_find_node_by_name(rootnp, "01_00d");
282 		if (!np)
283 			goto bad;
284 	}
285 	pp = of_find_property(np, "reg", &len);
286 	if (!pp)
287 		goto bad;
288 	leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
289 
290 	/* Find GPTIMER Timer Registers base address otherwise bail out. */
291 	nnp = rootnp;
292 	do {
293 		np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
294 		if (!np) {
295 			np = of_find_node_by_name(nnp, "01_011");
296 			if (!np)
297 				goto bad;
298 		}
299 
300 		ampopts = 0;
301 		pp = of_find_property(np, "ampopts", &len);
302 		if (pp) {
303 			ampopts = *(int *)pp->value;
304 			if (ampopts == 0) {
305 				/* Skip this instance, resource already
306 				 * allocated by other OS */
307 				nnp = np;
308 				continue;
309 			}
310 		}
311 
312 		/* Select Timer-Instance on Timer Core. Default is zero */
313 		leon3_gptimer_idx = ampopts & 0x7;
314 
315 		pp = of_find_property(np, "reg", &len);
316 		if (pp)
317 			leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
318 						pp->value;
319 		pp = of_find_property(np, "interrupts", &len);
320 		if (pp)
321 			leon3_gptimer_irq = *(unsigned int *)pp->value;
322 	} while (0);
323 
324 	if (!(leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq))
325 		goto bad;
326 
327 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
328 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
329 				(((1000000 / HZ) - 1)));
330 	LEON3_BYPASS_STORE_PA(
331 			&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
332 
333 #ifdef CONFIG_SMP
334 	leon3_ticker_irq = leon3_gptimer_irq + 1 + leon3_gptimer_idx;
335 
336 	if (!(LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config) &
337 	      (1<<LEON3_GPTIMER_SEPIRQ))) {
338 		printk(KERN_ERR "timer not configured with separate irqs\n");
339 		BUG();
340 	}
341 
342 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].val,
343 				0);
344 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].rld,
345 				(((1000000/HZ) - 1)));
346 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].ctrl,
347 				0);
348 #endif
349 
350 	/*
351 	 * The IRQ controller may (if implemented) consist of multiple
352 	 * IRQ controllers, each mapped on a 4Kb boundary.
353 	 * Each CPU may be routed to different IRQCTRLs, however
354 	 * we assume that all CPUs (in SMP system) is routed to the
355 	 * same IRQ Controller, and for non-SMP only one IRQCTRL is
356 	 * accessed anyway.
357 	 * In AMP systems, Linux must run on CPU0 for the time being.
358 	 */
359 	icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[boot_cpu_id/8]);
360 	icsel = (icsel >> ((7 - (boot_cpu_id&0x7)) * 4)) & 0xf;
361 	leon3_irqctrl_regs += icsel;
362 
363 	/* Mask all IRQs on boot-cpu IRQ controller */
364 	LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[boot_cpu_id], 0);
365 
366 	/* Probe extended IRQ controller */
367 	eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
368 		>> 16) & 0xf;
369 	if (eirq != 0)
370 		leon_eirq_setup(eirq);
371 
372 	irq = _leon_build_device_irq(NULL, leon3_gptimer_irq+leon3_gptimer_idx);
373 	err = request_irq(irq, counter_fn, IRQF_TIMER, "timer", NULL);
374 	if (err) {
375 		printk(KERN_ERR "unable to attach timer IRQ%d\n", irq);
376 		prom_halt();
377 	}
378 
379 #ifdef CONFIG_SMP
380 	{
381 		unsigned long flags;
382 
383 		/*
384 		 * In SMP, sun4m adds a IPI handler to IRQ trap handler that
385 		 * LEON never must take, sun4d and LEON overwrites the branch
386 		 * with a NOP.
387 		 */
388 		local_irq_save(flags);
389 		patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
390 		local_flush_cache_all();
391 		local_irq_restore(flags);
392 	}
393 #endif
394 
395 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
396 			      LEON3_GPTIMER_EN |
397 			      LEON3_GPTIMER_RL |
398 			      LEON3_GPTIMER_LD |
399 			      LEON3_GPTIMER_IRQEN);
400 
401 #ifdef CONFIG_SMP
402 	/* Install per-cpu IRQ handler for broadcasted ticker */
403 	irq = leon_build_device_irq(leon3_ticker_irq, handle_percpu_irq,
404 				    "per-cpu", 0);
405 	err = request_irq(irq, leon_percpu_timer_interrupt,
406 			  IRQF_PERCPU | IRQF_TIMER, "ticker",
407 			  NULL);
408 	if (err) {
409 		printk(KERN_ERR "unable to attach ticker IRQ%d\n", irq);
410 		prom_halt();
411 	}
412 
413 	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].ctrl,
414 			      LEON3_GPTIMER_EN |
415 			      LEON3_GPTIMER_RL |
416 			      LEON3_GPTIMER_LD |
417 			      LEON3_GPTIMER_IRQEN);
418 #endif
419 	return;
420 bad:
421 	printk(KERN_ERR "No Timer/irqctrl found\n");
422 	BUG();
423 	return;
424 }
425 
426 void leon_clear_clock_irq(void)
427 {
428 }
429 
430 void leon_load_profile_irq(int cpu, unsigned int limit)
431 {
432 	BUG();
433 }
434 
435 void __init leon_trans_init(struct device_node *dp)
436 {
437 	if (strcmp(dp->type, "cpu") == 0 && strcmp(dp->name, "<NULL>") == 0) {
438 		struct property *p;
439 		p = of_find_property(dp, "mid", (void *)0);
440 		if (p) {
441 			int mid;
442 			dp->name = prom_early_alloc(5 + 1);
443 			memcpy(&mid, p->value, p->length);
444 			sprintf((char *)dp->name, "cpu%.2d", mid);
445 		}
446 	}
447 }
448 
449 void __initdata (*prom_amba_init)(struct device_node *dp, struct device_node ***nextp) = 0;
450 
451 void __init leon_node_init(struct device_node *dp, struct device_node ***nextp)
452 {
453 	if (prom_amba_init &&
454 	    strcmp(dp->type, "ambapp") == 0 &&
455 	    strcmp(dp->name, "ambapp0") == 0) {
456 		prom_amba_init(dp, nextp);
457 	}
458 }
459 
460 #ifdef CONFIG_SMP
461 
462 void leon_set_cpu_int(int cpu, int level)
463 {
464 	unsigned long mask;
465 	mask = get_irqmask(level);
466 	LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->force[cpu], mask);
467 }
468 
469 static void leon_clear_ipi(int cpu, int level)
470 {
471 	unsigned long mask;
472 	mask = get_irqmask(level);
473 	LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->force[cpu], mask<<16);
474 }
475 
476 static void leon_set_udt(int cpu)
477 {
478 }
479 
480 void leon_clear_profile_irq(int cpu)
481 {
482 }
483 
484 void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
485 {
486 	unsigned long mask, flags, *addr;
487 	mask = get_irqmask(irq_nr);
488 	spin_lock_irqsave(&leon_irq_lock, flags);
489 	addr = (unsigned long *)LEON_IMASK(cpu);
490 	LEON3_BYPASS_STORE_PA(addr, (LEON3_BYPASS_LOAD_PA(addr) | mask));
491 	spin_unlock_irqrestore(&leon_irq_lock, flags);
492 }
493 
494 #endif
495 
496 void __init leon_init_IRQ(void)
497 {
498 	sparc_irq_config.init_timers      = leon_init_timers;
499 	sparc_irq_config.build_device_irq = _leon_build_device_irq;
500 
501 	BTFIXUPSET_CALL(clear_clock_irq, leon_clear_clock_irq,
502 			BTFIXUPCALL_NORM);
503 	BTFIXUPSET_CALL(load_profile_irq, leon_load_profile_irq,
504 			BTFIXUPCALL_NOP);
505 
506 #ifdef CONFIG_SMP
507 	BTFIXUPSET_CALL(set_cpu_int, leon_set_cpu_int, BTFIXUPCALL_NORM);
508 	BTFIXUPSET_CALL(clear_cpu_int, leon_clear_ipi, BTFIXUPCALL_NORM);
509 	BTFIXUPSET_CALL(set_irq_udt, leon_set_udt, BTFIXUPCALL_NORM);
510 #endif
511 
512 }
513 
514 void __init leon_init(void)
515 {
516 	of_pdt_build_more = &leon_node_init;
517 }
518