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 cpumask_t mask;
110
111 cpumask_and(&mask, cpu_online_mask, affinity);
112 if (cpumask_equal(&mask, cpu_online_mask) || cpumask_empty(&mask))
113 return boot_cpu_id;
114 else
115 return cpumask_first(&mask);
116 }
117 #else
118 #define irq_choose_cpu(affinity) boot_cpu_id
119 #endif
120
leon_set_affinity(struct irq_data * data,const struct cpumask * dest,bool force)121 static int leon_set_affinity(struct irq_data *data, const struct cpumask *dest,
122 bool force)
123 {
124 unsigned long mask, oldmask, flags;
125 int oldcpu, newcpu;
126
127 mask = (unsigned long)data->chip_data;
128 oldcpu = irq_choose_cpu(irq_data_get_affinity_mask(data));
129 newcpu = irq_choose_cpu(dest);
130
131 if (oldcpu == newcpu)
132 goto out;
133
134 /* unmask on old CPU first before enabling on the selected CPU */
135 spin_lock_irqsave(&leon_irq_lock, flags);
136 oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(oldcpu));
137 LEON3_BYPASS_STORE_PA(LEON_IMASK(oldcpu), (oldmask & ~mask));
138 oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(newcpu));
139 LEON3_BYPASS_STORE_PA(LEON_IMASK(newcpu), (oldmask | mask));
140 spin_unlock_irqrestore(&leon_irq_lock, flags);
141 out:
142 return IRQ_SET_MASK_OK;
143 }
144
leon_unmask_irq(struct irq_data * data)145 static void leon_unmask_irq(struct irq_data *data)
146 {
147 unsigned long mask, oldmask, flags;
148 int cpu;
149
150 mask = (unsigned long)data->chip_data;
151 cpu = irq_choose_cpu(irq_data_get_affinity_mask(data));
152 spin_lock_irqsave(&leon_irq_lock, flags);
153 oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
154 LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask | mask));
155 spin_unlock_irqrestore(&leon_irq_lock, flags);
156 }
157
leon_mask_irq(struct irq_data * data)158 static void leon_mask_irq(struct irq_data *data)
159 {
160 unsigned long mask, oldmask, flags;
161 int cpu;
162
163 mask = (unsigned long)data->chip_data;
164 cpu = irq_choose_cpu(irq_data_get_affinity_mask(data));
165 spin_lock_irqsave(&leon_irq_lock, flags);
166 oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
167 LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask & ~mask));
168 spin_unlock_irqrestore(&leon_irq_lock, flags);
169 }
170
leon_startup_irq(struct irq_data * data)171 static unsigned int leon_startup_irq(struct irq_data *data)
172 {
173 irq_link(data->irq);
174 leon_unmask_irq(data);
175 return 0;
176 }
177
leon_shutdown_irq(struct irq_data * data)178 static void leon_shutdown_irq(struct irq_data *data)
179 {
180 leon_mask_irq(data);
181 irq_unlink(data->irq);
182 }
183
184 /* Used by external level sensitive IRQ handlers on the LEON: ACK IRQ ctrl */
leon_eoi_irq(struct irq_data * data)185 static void leon_eoi_irq(struct irq_data *data)
186 {
187 unsigned long mask = (unsigned long)data->chip_data;
188
189 if (mask & LEON_DO_ACK_HW)
190 LEON3_BYPASS_STORE_PA(LEON_IACK, mask & ~LEON_DO_ACK_HW);
191 }
192
193 static struct irq_chip leon_irq = {
194 .name = "leon",
195 .irq_startup = leon_startup_irq,
196 .irq_shutdown = leon_shutdown_irq,
197 .irq_mask = leon_mask_irq,
198 .irq_unmask = leon_unmask_irq,
199 .irq_eoi = leon_eoi_irq,
200 .irq_set_affinity = leon_set_affinity,
201 };
202
203 /*
204 * Build a LEON IRQ for the edge triggered LEON IRQ controller:
205 * Edge (normal) IRQ - handle_simple_irq, ack=DON'T-CARE, never ack
206 * Level IRQ (PCI|Level-GPIO) - handle_fasteoi_irq, ack=1, ack after ISR
207 * Per-CPU Edge - handle_percpu_irq, ack=0
208 */
leon_build_device_irq(unsigned int real_irq,irq_flow_handler_t flow_handler,const char * name,int do_ack)209 unsigned int leon_build_device_irq(unsigned int real_irq,
210 irq_flow_handler_t flow_handler,
211 const char *name, int do_ack)
212 {
213 unsigned int irq;
214 unsigned long mask;
215 struct irq_desc *desc;
216
217 irq = 0;
218 mask = leon_get_irqmask(real_irq);
219 if (mask == 0)
220 goto out;
221
222 irq = irq_alloc(real_irq, real_irq);
223 if (irq == 0)
224 goto out;
225
226 if (do_ack)
227 mask |= LEON_DO_ACK_HW;
228
229 desc = irq_to_desc(irq);
230 if (!desc || !desc->handle_irq || desc->handle_irq == handle_bad_irq) {
231 irq_set_chip_and_handler_name(irq, &leon_irq,
232 flow_handler, name);
233 irq_set_chip_data(irq, (void *)mask);
234 }
235
236 out:
237 return irq;
238 }
239
_leon_build_device_irq(struct platform_device * op,unsigned int real_irq)240 static unsigned int _leon_build_device_irq(struct platform_device *op,
241 unsigned int real_irq)
242 {
243 return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
244 }
245
leon_update_virq_handling(unsigned int virq,irq_flow_handler_t flow_handler,const char * name,int do_ack)246 void leon_update_virq_handling(unsigned int virq,
247 irq_flow_handler_t flow_handler,
248 const char *name, int do_ack)
249 {
250 unsigned long mask = (unsigned long)irq_get_chip_data(virq);
251
252 mask &= ~LEON_DO_ACK_HW;
253 if (do_ack)
254 mask |= LEON_DO_ACK_HW;
255
256 irq_set_chip_and_handler_name(virq, &leon_irq,
257 flow_handler, name);
258 irq_set_chip_data(virq, (void *)mask);
259 }
260
leon_cycles_offset(void)261 static u32 leon_cycles_offset(void)
262 {
263 u32 rld, val, ctrl, off;
264
265 rld = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld);
266 val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
267 ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
268 if (LEON3_GPTIMER_CTRL_ISPENDING(ctrl)) {
269 val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
270 off = 2 * rld - val;
271 } else {
272 off = rld - val;
273 }
274
275 return off;
276 }
277
278 #ifdef CONFIG_SMP
279
280 /* smp clockevent irq */
leon_percpu_timer_ce_interrupt(int irq,void * unused)281 static irqreturn_t leon_percpu_timer_ce_interrupt(int irq, void *unused)
282 {
283 struct clock_event_device *ce;
284 int cpu = smp_processor_id();
285
286 leon_clear_profile_irq(cpu);
287
288 if (cpu == boot_cpu_id)
289 timer_interrupt(irq, NULL);
290
291 ce = &per_cpu(sparc32_clockevent, cpu);
292
293 irq_enter();
294 if (ce->event_handler)
295 ce->event_handler(ce);
296 irq_exit();
297
298 return IRQ_HANDLED;
299 }
300
301 #endif /* CONFIG_SMP */
302
leon_init_timers(void)303 void __init leon_init_timers(void)
304 {
305 int irq, eirq;
306 struct device_node *rootnp, *np, *nnp;
307 struct property *pp;
308 int len;
309 int icsel;
310 int ampopts;
311 int err;
312 u32 config;
313 u32 ctrl;
314
315 sparc_config.get_cycles_offset = leon_cycles_offset;
316 sparc_config.cs_period = 1000000 / HZ;
317 sparc_config.features |= FEAT_L10_CLOCKSOURCE;
318
319 #ifndef CONFIG_SMP
320 sparc_config.features |= FEAT_L10_CLOCKEVENT;
321 #endif
322
323 leondebug_irq_disable = 0;
324 leon_debug_irqout = 0;
325 master_l10_counter = (u32 __iomem *)&dummy_master_l10_counter;
326 dummy_master_l10_counter = 0;
327
328 rootnp = of_find_node_by_path("/ambapp0");
329 if (!rootnp)
330 goto bad;
331
332 /* Find System ID: GRLIB build ID and optional CHIP ID */
333 pp = of_find_property(rootnp, "systemid", &len);
334 if (pp)
335 amba_system_id = *(unsigned long *)pp->value;
336
337 /* Find IRQMP IRQ Controller Registers base adr otherwise bail out */
338 np = of_find_node_by_name(rootnp, "GAISLER_IRQMP");
339 if (!np) {
340 np = of_find_node_by_name(rootnp, "01_00d");
341 if (!np)
342 goto bad;
343 }
344 pp = of_find_property(np, "reg", &len);
345 if (!pp)
346 goto bad;
347 leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
348
349 /* Find GPTIMER Timer Registers base address otherwise bail out. */
350 nnp = rootnp;
351
352 retry:
353 np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
354 if (!np) {
355 np = of_find_node_by_name(nnp, "01_011");
356 if (!np)
357 goto bad;
358 }
359
360 ampopts = 0;
361 pp = of_find_property(np, "ampopts", &len);
362 if (pp) {
363 ampopts = *(int *)pp->value;
364 if (ampopts == 0) {
365 /* Skip this instance, resource already
366 * allocated by other OS */
367 nnp = np;
368 goto retry;
369 }
370 }
371
372 /* Select Timer-Instance on Timer Core. Default is zero */
373 leon3_gptimer_idx = ampopts & 0x7;
374
375 pp = of_find_property(np, "reg", &len);
376 if (pp)
377 leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
378 pp->value;
379 pp = of_find_property(np, "interrupts", &len);
380 if (pp)
381 leon3_gptimer_irq = *(unsigned int *)pp->value;
382
383 if (!(leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq))
384 goto bad;
385
386 ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
387 LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
388 ctrl | LEON3_GPTIMER_CTRL_PENDING);
389 ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
390
391 if ((ctrl & LEON3_GPTIMER_CTRL_PENDING) != 0)
392 leon3_gptimer_ackmask = ~LEON3_GPTIMER_CTRL_PENDING;
393 else
394 leon3_gptimer_ackmask = ~0;
395
396 LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
397 LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
398 (((1000000 / HZ) - 1)));
399 LEON3_BYPASS_STORE_PA(
400 &leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
401
402 /*
403 * The IRQ controller may (if implemented) consist of multiple
404 * IRQ controllers, each mapped on a 4Kb boundary.
405 * Each CPU may be routed to different IRQCTRLs, however
406 * we assume that all CPUs (in SMP system) is routed to the
407 * same IRQ Controller, and for non-SMP only one IRQCTRL is
408 * accessed anyway.
409 * In AMP systems, Linux must run on CPU0 for the time being.
410 */
411 icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[boot_cpu_id/8]);
412 icsel = (icsel >> ((7 - (boot_cpu_id&0x7)) * 4)) & 0xf;
413 leon3_irqctrl_regs += icsel;
414
415 /* Mask all IRQs on boot-cpu IRQ controller */
416 LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[boot_cpu_id], 0);
417
418 /* Probe extended IRQ controller */
419 eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
420 >> 16) & 0xf;
421 if (eirq != 0)
422 leon_eirq_setup(eirq);
423
424 #ifdef CONFIG_SMP
425 {
426 unsigned long flags;
427
428 /*
429 * In SMP, sun4m adds a IPI handler to IRQ trap handler that
430 * LEON never must take, sun4d and LEON overwrites the branch
431 * with a NOP.
432 */
433 local_irq_save(flags);
434 patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
435 local_ops->cache_all();
436 local_irq_restore(flags);
437 }
438 #endif
439
440 config = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config);
441 if (config & (1 << LEON3_GPTIMER_SEPIRQ))
442 leon3_gptimer_irq += leon3_gptimer_idx;
443 else if ((config & LEON3_GPTIMER_TIMERS) > 1)
444 pr_warn("GPTIMER uses shared irqs, using other timers of the same core will fail.\n");
445
446 #ifdef CONFIG_SMP
447 /* Install per-cpu IRQ handler for broadcasted ticker */
448 irq = leon_build_device_irq(leon3_gptimer_irq, handle_percpu_irq,
449 "per-cpu", 0);
450 err = request_irq(irq, leon_percpu_timer_ce_interrupt,
451 IRQF_PERCPU | IRQF_TIMER, "timer", NULL);
452 #else
453 irq = _leon_build_device_irq(NULL, leon3_gptimer_irq);
454 err = request_irq(irq, timer_interrupt, IRQF_TIMER, "timer", NULL);
455 #endif
456 if (err) {
457 pr_err("Unable to attach timer IRQ%d\n", irq);
458 prom_halt();
459 }
460 LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
461 LEON3_GPTIMER_EN |
462 LEON3_GPTIMER_RL |
463 LEON3_GPTIMER_LD |
464 LEON3_GPTIMER_IRQEN);
465 return;
466 bad:
467 printk(KERN_ERR "No Timer/irqctrl found\n");
468 BUG();
469 return;
470 }
471
leon_clear_clock_irq(void)472 static void leon_clear_clock_irq(void)
473 {
474 u32 ctrl;
475
476 ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
477 LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
478 ctrl & leon3_gptimer_ackmask);
479 }
480
leon_load_profile_irq(int cpu,unsigned int limit)481 static void leon_load_profile_irq(int cpu, unsigned int limit)
482 {
483 }
484
485 #ifdef CONFIG_SMP
leon_clear_profile_irq(int cpu)486 void leon_clear_profile_irq(int cpu)
487 {
488 }
489
leon_enable_irq_cpu(unsigned int irq_nr,unsigned int cpu)490 void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
491 {
492 unsigned long mask, flags, *addr;
493 mask = leon_get_irqmask(irq_nr);
494 spin_lock_irqsave(&leon_irq_lock, flags);
495 addr = (unsigned long *)LEON_IMASK(cpu);
496 LEON3_BYPASS_STORE_PA(addr, (LEON3_BYPASS_LOAD_PA(addr) | mask));
497 spin_unlock_irqrestore(&leon_irq_lock, flags);
498 }
499
500 #endif
501
leon_init_IRQ(void)502 void __init leon_init_IRQ(void)
503 {
504 sparc_config.init_timers = leon_init_timers;
505 sparc_config.build_device_irq = _leon_build_device_irq;
506 sparc_config.clock_rate = 1000000;
507 sparc_config.clear_clock_irq = leon_clear_clock_irq;
508 sparc_config.load_profile_irq = leon_load_profile_irq;
509 }
510