1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB
4 * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB
5 */
6
7 #include <linux/kernel.h>
8 #include <linux/errno.h>
9 #include <linux/mutex.h>
10 #include <linux/of.h>
11 #include <linux/interrupt.h>
12 #include <linux/clocksource.h>
13 #include <linux/clockchips.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 "kernel.h"
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 volatile u32 dummy_master_l10_counter;
35 unsigned long amba_system_id;
36 static DEFINE_SPINLOCK(leon_irq_lock);
37
38 static unsigned long leon3_gptimer_idx; /* Timer Index (0..6) within Timer Core */
39 static unsigned long leon3_gptimer_ackmask; /* For clearing pending bit */
40 unsigned long leon3_gptimer_irq; /* interrupt controller irq number */
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 */
leon_eirq_get(int cpu)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 */
leon_handle_ext_irq(struct irq_desc * desc)55 static void leon_handle_ext_irq(struct irq_desc *desc)
56 {
57 unsigned int eirq;
58 struct irq_bucket *p;
59 int cpu = sparc_leon3_cpuid();
60
61 eirq = leon_eirq_get(cpu);
62 p = irq_map[eirq];
63 if ((eirq & 0x10) && p && p->irq) /* bit4 tells if IRQ happened */
64 generic_handle_irq(p->irq);
65 }
66
67 /* The extended IRQ controller has been found, this function registers it */
leon_eirq_setup(unsigned int eirq)68 static void leon_eirq_setup(unsigned int eirq)
69 {
70 unsigned long mask, oldmask;
71 unsigned int veirq;
72
73 if (eirq < 1 || eirq > 0xf) {
74 printk(KERN_ERR "LEON EXT IRQ NUMBER BAD: %d\n", eirq);
75 return;
76 }
77
78 veirq = leon_build_device_irq(eirq, leon_handle_ext_irq, "extirq", 0);
79
80 /*
81 * Unmask the Extended IRQ, the IRQs routed through the Ext-IRQ
82 * controller have a mask-bit of their own, so this is safe.
83 */
84 irq_link(veirq);
85 mask = 1 << eirq;
86 oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(boot_cpu_id));
87 LEON3_BYPASS_STORE_PA(LEON_IMASK(boot_cpu_id), (oldmask | mask));
88 sparc_leon_eirq = eirq;
89 }
90
leon_get_irqmask(unsigned int irq)91 unsigned long leon_get_irqmask(unsigned int irq)
92 {
93 unsigned long mask;
94
95 if (!irq || ((irq > 0xf) && !sparc_leon_eirq)
96 || ((irq > 0x1f) && sparc_leon_eirq)) {
97 printk(KERN_ERR
98 "leon_get_irqmask: false irq number: %d\n", irq);
99 mask = 0;
100 } else {
101 mask = LEON_HARD_INT(irq);
102 }
103 return mask;
104 }
105
106 #ifdef CONFIG_SMP
irq_choose_cpu(const struct cpumask * affinity)107 static int irq_choose_cpu(const struct cpumask *affinity)
108 {
109 unsigned int cpu = cpumask_first_and(affinity, cpu_online_mask);
110
111 if (cpumask_subset(cpu_online_mask, affinity) || cpu >= nr_cpu_ids)
112 return boot_cpu_id;
113 else
114 return cpu;
115 }
116 #else
117 #define irq_choose_cpu(affinity) boot_cpu_id
118 #endif
119
leon_set_affinity(struct irq_data * data,const struct cpumask * dest,bool force)120 static int leon_set_affinity(struct irq_data *data, const struct cpumask *dest,
121 bool force)
122 {
123 unsigned long mask, oldmask, flags;
124 int oldcpu, newcpu;
125
126 mask = (unsigned long)data->chip_data;
127 oldcpu = irq_choose_cpu(irq_data_get_affinity_mask(data));
128 newcpu = irq_choose_cpu(dest);
129
130 if (oldcpu == newcpu)
131 goto out;
132
133 /* unmask on old CPU first before enabling on the selected CPU */
134 spin_lock_irqsave(&leon_irq_lock, flags);
135 oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(oldcpu));
136 LEON3_BYPASS_STORE_PA(LEON_IMASK(oldcpu), (oldmask & ~mask));
137 oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(newcpu));
138 LEON3_BYPASS_STORE_PA(LEON_IMASK(newcpu), (oldmask | mask));
139 spin_unlock_irqrestore(&leon_irq_lock, flags);
140 out:
141 return IRQ_SET_MASK_OK;
142 }
143
leon_unmask_irq(struct irq_data * data)144 static void leon_unmask_irq(struct irq_data *data)
145 {
146 unsigned long mask, oldmask, flags;
147 int cpu;
148
149 mask = (unsigned long)data->chip_data;
150 cpu = irq_choose_cpu(irq_data_get_affinity_mask(data));
151 spin_lock_irqsave(&leon_irq_lock, flags);
152 oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
153 LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask | mask));
154 spin_unlock_irqrestore(&leon_irq_lock, flags);
155 }
156
leon_mask_irq(struct irq_data * data)157 static void leon_mask_irq(struct irq_data *data)
158 {
159 unsigned long mask, oldmask, flags;
160 int cpu;
161
162 mask = (unsigned long)data->chip_data;
163 cpu = irq_choose_cpu(irq_data_get_affinity_mask(data));
164 spin_lock_irqsave(&leon_irq_lock, flags);
165 oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
166 LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask & ~mask));
167 spin_unlock_irqrestore(&leon_irq_lock, flags);
168 }
169
leon_startup_irq(struct irq_data * data)170 static unsigned int leon_startup_irq(struct irq_data *data)
171 {
172 irq_link(data->irq);
173 leon_unmask_irq(data);
174 return 0;
175 }
176
leon_shutdown_irq(struct irq_data * data)177 static void leon_shutdown_irq(struct irq_data *data)
178 {
179 leon_mask_irq(data);
180 irq_unlink(data->irq);
181 }
182
183 /* Used by external level sensitive IRQ handlers on the LEON: ACK IRQ ctrl */
leon_eoi_irq(struct irq_data * data)184 static void leon_eoi_irq(struct irq_data *data)
185 {
186 unsigned long mask = (unsigned long)data->chip_data;
187
188 if (mask & LEON_DO_ACK_HW)
189 LEON3_BYPASS_STORE_PA(LEON_IACK, mask & ~LEON_DO_ACK_HW);
190 }
191
192 static struct irq_chip leon_irq = {
193 .name = "leon",
194 .irq_startup = leon_startup_irq,
195 .irq_shutdown = leon_shutdown_irq,
196 .irq_mask = leon_mask_irq,
197 .irq_unmask = leon_unmask_irq,
198 .irq_eoi = leon_eoi_irq,
199 .irq_set_affinity = leon_set_affinity,
200 };
201
202 /*
203 * Build a LEON IRQ for the edge triggered LEON IRQ controller:
204 * Edge (normal) IRQ - handle_simple_irq, ack=DON'T-CARE, never ack
205 * Level IRQ (PCI|Level-GPIO) - handle_fasteoi_irq, ack=1, ack after ISR
206 * Per-CPU Edge - handle_percpu_irq, ack=0
207 */
leon_build_device_irq(unsigned int real_irq,irq_flow_handler_t flow_handler,const char * name,int do_ack)208 unsigned int leon_build_device_irq(unsigned int real_irq,
209 irq_flow_handler_t flow_handler,
210 const char *name, int do_ack)
211 {
212 unsigned int irq;
213 unsigned long mask;
214 struct irq_desc *desc;
215
216 irq = 0;
217 mask = leon_get_irqmask(real_irq);
218 if (mask == 0)
219 goto out;
220
221 irq = irq_alloc(real_irq, real_irq);
222 if (irq == 0)
223 goto out;
224
225 if (do_ack)
226 mask |= LEON_DO_ACK_HW;
227
228 desc = irq_to_desc(irq);
229 if (!desc || !desc->handle_irq || desc->handle_irq == handle_bad_irq) {
230 irq_set_chip_and_handler_name(irq, &leon_irq,
231 flow_handler, name);
232 irq_set_chip_data(irq, (void *)mask);
233 }
234
235 out:
236 return irq;
237 }
238
_leon_build_device_irq(struct platform_device * op,unsigned int real_irq)239 static unsigned int _leon_build_device_irq(struct platform_device *op,
240 unsigned int real_irq)
241 {
242 return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
243 }
244
leon_update_virq_handling(unsigned int virq,irq_flow_handler_t flow_handler,const char * name,int do_ack)245 void leon_update_virq_handling(unsigned int virq,
246 irq_flow_handler_t flow_handler,
247 const char *name, int do_ack)
248 {
249 unsigned long mask = (unsigned long)irq_get_chip_data(virq);
250
251 mask &= ~LEON_DO_ACK_HW;
252 if (do_ack)
253 mask |= LEON_DO_ACK_HW;
254
255 irq_set_chip_and_handler_name(virq, &leon_irq,
256 flow_handler, name);
257 irq_set_chip_data(virq, (void *)mask);
258 }
259
leon_cycles_offset(void)260 static u32 leon_cycles_offset(void)
261 {
262 u32 rld, val, ctrl, off;
263
264 rld = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld);
265 val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
266 ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
267 if (LEON3_GPTIMER_CTRL_ISPENDING(ctrl)) {
268 val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
269 off = 2 * rld - val;
270 } else {
271 off = rld - val;
272 }
273
274 return off;
275 }
276
277 #ifdef CONFIG_SMP
278
279 /* smp clockevent irq */
leon_percpu_timer_ce_interrupt(int irq,void * unused)280 static irqreturn_t leon_percpu_timer_ce_interrupt(int irq, void *unused)
281 {
282 struct clock_event_device *ce;
283 int cpu = smp_processor_id();
284
285 leon_clear_profile_irq(cpu);
286
287 if (cpu == boot_cpu_id)
288 timer_interrupt(irq, NULL);
289
290 ce = &per_cpu(sparc32_clockevent, cpu);
291
292 irq_enter();
293 if (ce->event_handler)
294 ce->event_handler(ce);
295 irq_exit();
296
297 return IRQ_HANDLED;
298 }
299
300 #endif /* CONFIG_SMP */
301
leon_init_timers(void)302 void __init leon_init_timers(void)
303 {
304 int irq, eirq;
305 struct device_node *rootnp, *np, *nnp;
306 struct property *pp;
307 int len;
308 int icsel;
309 int ampopts;
310 int err;
311 u32 config;
312 u32 ctrl;
313
314 sparc_config.get_cycles_offset = leon_cycles_offset;
315 sparc_config.cs_period = 1000000 / HZ;
316 sparc_config.features |= FEAT_L10_CLOCKSOURCE;
317
318 #ifndef CONFIG_SMP
319 sparc_config.features |= FEAT_L10_CLOCKEVENT;
320 #endif
321
322 leondebug_irq_disable = 0;
323 leon_debug_irqout = 0;
324 master_l10_counter = (u32 __iomem *)&dummy_master_l10_counter;
325 dummy_master_l10_counter = 0;
326
327 rootnp = of_find_node_by_path("/ambapp0");
328 if (!rootnp)
329 goto bad;
330
331 /* Find System ID: GRLIB build ID and optional CHIP ID */
332 pp = of_find_property(rootnp, "systemid", &len);
333 if (pp)
334 amba_system_id = *(unsigned long *)pp->value;
335
336 /* Find IRQMP IRQ Controller Registers base adr otherwise bail out */
337 np = of_find_node_by_name(rootnp, "GAISLER_IRQMP");
338 if (!np) {
339 np = of_find_node_by_name(rootnp, "01_00d");
340 if (!np)
341 goto bad;
342 }
343 pp = of_find_property(np, "reg", &len);
344 if (!pp)
345 goto bad;
346 leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
347
348 /* Find GPTIMER Timer Registers base address otherwise bail out. */
349 nnp = rootnp;
350
351 retry:
352 np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
353 if (!np) {
354 np = of_find_node_by_name(nnp, "01_011");
355 if (!np)
356 goto bad;
357 }
358
359 ampopts = 0;
360 pp = of_find_property(np, "ampopts", &len);
361 if (pp) {
362 ampopts = *(int *)pp->value;
363 if (ampopts == 0) {
364 /* Skip this instance, resource already
365 * allocated by other OS */
366 nnp = np;
367 goto retry;
368 }
369 }
370
371 /* Select Timer-Instance on Timer Core. Default is zero */
372 leon3_gptimer_idx = ampopts & 0x7;
373
374 pp = of_find_property(np, "reg", &len);
375 if (pp)
376 leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
377 pp->value;
378 pp = of_find_property(np, "interrupts", &len);
379 if (pp)
380 leon3_gptimer_irq = *(unsigned int *)pp->value;
381
382 if (!(leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq))
383 goto bad;
384
385 ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
386 LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
387 ctrl | LEON3_GPTIMER_CTRL_PENDING);
388 ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
389
390 if ((ctrl & LEON3_GPTIMER_CTRL_PENDING) != 0)
391 leon3_gptimer_ackmask = ~LEON3_GPTIMER_CTRL_PENDING;
392 else
393 leon3_gptimer_ackmask = ~0;
394
395 LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
396 LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
397 (((1000000 / HZ) - 1)));
398 LEON3_BYPASS_STORE_PA(
399 &leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
400
401 /*
402 * The IRQ controller may (if implemented) consist of multiple
403 * IRQ controllers, each mapped on a 4Kb boundary.
404 * Each CPU may be routed to different IRQCTRLs, however
405 * we assume that all CPUs (in SMP system) is routed to the
406 * same IRQ Controller, and for non-SMP only one IRQCTRL is
407 * accessed anyway.
408 * In AMP systems, Linux must run on CPU0 for the time being.
409 */
410 icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[boot_cpu_id/8]);
411 icsel = (icsel >> ((7 - (boot_cpu_id&0x7)) * 4)) & 0xf;
412 leon3_irqctrl_regs += icsel;
413
414 /* Mask all IRQs on boot-cpu IRQ controller */
415 LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[boot_cpu_id], 0);
416
417 /* Probe extended IRQ controller */
418 eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
419 >> 16) & 0xf;
420 if (eirq != 0)
421 leon_eirq_setup(eirq);
422
423 #ifdef CONFIG_SMP
424 {
425 unsigned long flags;
426
427 /*
428 * In SMP, sun4m adds a IPI handler to IRQ trap handler that
429 * LEON never must take, sun4d and LEON overwrites the branch
430 * with a NOP.
431 */
432 local_irq_save(flags);
433 patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
434 local_ops->cache_all();
435 local_irq_restore(flags);
436 }
437 #endif
438
439 config = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config);
440 if (config & (1 << LEON3_GPTIMER_SEPIRQ))
441 leon3_gptimer_irq += leon3_gptimer_idx;
442 else if ((config & LEON3_GPTIMER_TIMERS) > 1)
443 pr_warn("GPTIMER uses shared irqs, using other timers of the same core will fail.\n");
444
445 #ifdef CONFIG_SMP
446 /* Install per-cpu IRQ handler for broadcasted ticker */
447 irq = leon_build_device_irq(leon3_gptimer_irq, handle_percpu_irq,
448 "per-cpu", 0);
449 err = request_irq(irq, leon_percpu_timer_ce_interrupt,
450 IRQF_PERCPU | IRQF_TIMER, "timer", NULL);
451 #else
452 irq = _leon_build_device_irq(NULL, leon3_gptimer_irq);
453 err = request_irq(irq, timer_interrupt, IRQF_TIMER, "timer", NULL);
454 #endif
455 if (err) {
456 pr_err("Unable to attach timer IRQ%d\n", irq);
457 prom_halt();
458 }
459 LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
460 LEON3_GPTIMER_EN |
461 LEON3_GPTIMER_RL |
462 LEON3_GPTIMER_LD |
463 LEON3_GPTIMER_IRQEN);
464 return;
465 bad:
466 printk(KERN_ERR "No Timer/irqctrl found\n");
467 BUG();
468 return;
469 }
470
leon_clear_clock_irq(void)471 static void leon_clear_clock_irq(void)
472 {
473 u32 ctrl;
474
475 ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
476 LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
477 ctrl & leon3_gptimer_ackmask);
478 }
479
leon_load_profile_irq(int cpu,unsigned int limit)480 static void leon_load_profile_irq(int cpu, unsigned int limit)
481 {
482 }
483
484 #ifdef CONFIG_SMP
leon_clear_profile_irq(int cpu)485 void leon_clear_profile_irq(int cpu)
486 {
487 }
488
leon_enable_irq_cpu(unsigned int irq_nr,unsigned int cpu)489 void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
490 {
491 unsigned long mask, flags, *addr;
492 mask = leon_get_irqmask(irq_nr);
493 spin_lock_irqsave(&leon_irq_lock, flags);
494 addr = (unsigned long *)LEON_IMASK(cpu);
495 LEON3_BYPASS_STORE_PA(addr, (LEON3_BYPASS_LOAD_PA(addr) | mask));
496 spin_unlock_irqrestore(&leon_irq_lock, flags);
497 }
498
499 #endif
500
leon_init_IRQ(void)501 void __init leon_init_IRQ(void)
502 {
503 sparc_config.init_timers = leon_init_timers;
504 sparc_config.build_device_irq = _leon_build_device_irq;
505 sparc_config.clock_rate = 1000000;
506 sparc_config.clear_clock_irq = leon_clear_clock_irq;
507 sparc_config.load_profile_irq = leon_load_profile_irq;
508 }
509