summaryrefslogtreecommitdiffstats
path: root/drivers/irqchip/irq-hip04.c
blob: 29b8f21b74d0a5868b7ee4034bee285c07bb332b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
/*
 * Hisilicon HiP04 INTC
 *
 * Copyright (C) 2002-2014 ARM Limited.
 * Copyright (c) 2013-2014 Hisilicon Ltd.
 * Copyright (c) 2013-2014 Linaro Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Interrupt architecture for the HIP04 INTC:
 *
 * o There is one Interrupt Distributor, which receives interrupts
 *   from system devices and sends them to the Interrupt Controllers.
 *
 * o There is one CPU Interface per CPU, which sends interrupts sent
 *   by the Distributor, and interrupts generated locally, to the
 *   associated CPU. The base address of the CPU interface is usually
 *   aliased so that the same address points to different chips depending
 *   on the CPU it is accessed from.
 *
 * Note that IRQs 0-31 are special - they are local to each CPU.
 * As such, the enable set/clear, pending set/clear and active bit
 * registers are banked per-cpu for these sources.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/smp.h>
#include <linux/cpu.h>
#include <linux/cpu_pm.h>
#include <linux/cpumask.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/irqdomain.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/irqchip/arm-gic.h>

#include <asm/irq.h>
#include <asm/exception.h>
#include <asm/smp_plat.h>

#include "irq-gic-common.h"
#include "irqchip.h"

#define HIP04_MAX_IRQS		510

struct hip04_irq_data {
	void __iomem *dist_base;
	void __iomem *cpu_base;
	struct irq_domain *domain;
	unsigned int nr_irqs;
};

static DEFINE_RAW_SPINLOCK(irq_controller_lock);

/*
 * The GIC mapping of CPU interfaces does not necessarily match
 * the logical CPU numbering.  Let's use a mapping as returned
 * by the GIC itself.
 */
#define NR_HIP04_CPU_IF 16
static u16 hip04_cpu_map[NR_HIP04_CPU_IF] __read_mostly;

static struct hip04_irq_data hip04_data __read_mostly;

static inline void __iomem *hip04_dist_base(struct irq_data *d)
{
	struct hip04_irq_data *hip04_data = irq_data_get_irq_chip_data(d);
	return hip04_data->dist_base;
}

static inline void __iomem *hip04_cpu_base(struct irq_data *d)
{
	struct hip04_irq_data *hip04_data = irq_data_get_irq_chip_data(d);
	return hip04_data->cpu_base;
}

static inline unsigned int hip04_irq(struct irq_data *d)
{
	return d->hwirq;
}

/*
 * Routines to acknowledge, disable and enable interrupts
 */
static void hip04_mask_irq(struct irq_data *d)
{
	u32 mask = 1 << (hip04_irq(d) % 32);

	raw_spin_lock(&irq_controller_lock);
	writel_relaxed(mask, hip04_dist_base(d) + GIC_DIST_ENABLE_CLEAR +
		       (hip04_irq(d) / 32) * 4);
	raw_spin_unlock(&irq_controller_lock);
}

static void hip04_unmask_irq(struct irq_data *d)
{
	u32 mask = 1 << (hip04_irq(d) % 32);

	raw_spin_lock(&irq_controller_lock);
	writel_relaxed(mask, hip04_dist_base(d) + GIC_DIST_ENABLE_SET +
		       (hip04_irq(d) / 32) * 4);
	raw_spin_unlock(&irq_controller_lock);
}

static void hip04_eoi_irq(struct irq_data *d)
{
	writel_relaxed(hip04_irq(d), hip04_cpu_base(d) + GIC_CPU_EOI);
}

static int hip04_irq_set_type(struct irq_data *d, unsigned int type)
{
	void __iomem *base = hip04_dist_base(d);
	unsigned int irq = hip04_irq(d);

	/* Interrupt configuration for SGIs can't be changed */
	if (irq < 16)
		return -EINVAL;

	if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
		return -EINVAL;

	raw_spin_lock(&irq_controller_lock);

	gic_configure_irq(irq, type, base, NULL);

	raw_spin_unlock(&irq_controller_lock);

	return 0;
}

#ifdef CONFIG_SMP
static int hip04_irq_set_affinity(struct irq_data *d,
				  const struct cpumask *mask_val,
				  bool force)
{
	void __iomem *reg;
	unsigned int cpu, shift = (hip04_irq(d) % 2) * 16;
	u32 val, mask, bit;

	if (!force)
		cpu = cpumask_any_and(mask_val, cpu_online_mask);
	else
		cpu = cpumask_first(mask_val);

	if (cpu >= NR_HIP04_CPU_IF || cpu >= nr_cpu_ids)
		return -EINVAL;

	raw_spin_lock(&irq_controller_lock);
	reg = hip04_dist_base(d) + GIC_DIST_TARGET + ((hip04_irq(d) * 2) & ~3);
	mask = 0xffff << shift;
	bit = hip04_cpu_map[cpu] << shift;
	val = readl_relaxed(reg) & ~mask;
	writel_relaxed(val | bit, reg);
	raw_spin_unlock(&irq_controller_lock);

	return IRQ_SET_MASK_OK;
}
#endif

static void __exception_irq_entry hip04_handle_irq(struct pt_regs *regs)
{
	u32 irqstat, irqnr;
	void __iomem *cpu_base = hip04_data.cpu_base;

	do {
		irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK);
		irqnr = irqstat & GICC_IAR_INT_ID_MASK;

		if (likely(irqnr > 15 && irqnr <= HIP04_MAX_IRQS)) {
			handle_domain_irq(hip04_data.domain, irqnr, regs);
			continue;
		}
		if (irqnr < 16) {
			writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
#ifdef CONFIG_SMP
			handle_IPI(irqnr, regs);
#endif
			continue;
		}
		break;
	} while (1);
}

static struct irq_chip hip04_irq_chip = {
	.name			= "HIP04 INTC",
	.irq_mask		= hip04_mask_irq,
	.irq_unmask		= hip04_unmask_irq,
	.irq_eoi		= hip04_eoi_irq,
	.irq_set_type		= hip04_irq_set_type,
#ifdef CONFIG_SMP
	.irq_set_affinity	= hip04_irq_set_affinity,
#endif
};

static u16 hip04_get_cpumask(struct hip04_irq_data *intc)
{
	void __iomem *base = intc->dist_base;
	u32 mask, i;

	for (i = mask = 0; i < 32; i += 2) {
		mask = readl_relaxed(base + GIC_DIST_TARGET + i * 2);
		mask |= mask >> 16;
		if (mask)
			break;
	}

	if (!mask)
		pr_crit("GIC CPU mask not found - kernel will fail to boot.\n");

	return mask;
}

static void __init hip04_irq_dist_init(struct hip04_irq_data *intc)
{
	unsigned int i;
	u32 cpumask;
	unsigned int nr_irqs = intc->nr_irqs;
	void __iomem *base = intc->dist_base;

	writel_relaxed(0, base + GIC_DIST_CTRL);

	/*
	 * Set all global interrupts to this CPU only.
	 */
	cpumask = hip04_get_cpumask(intc);
	cpumask |= cpumask << 16;
	for (i = 32; i < nr_irqs; i += 2)
		writel_relaxed(cpumask, base + GIC_DIST_TARGET + ((i * 2) & ~3));

	gic_dist_config(base, nr_irqs, NULL);

	writel_relaxed(1, base + GIC_DIST_CTRL);
}

static void hip04_irq_cpu_init(struct hip04_irq_data *intc)
{
	void __iomem *dist_base = intc->dist_base;
	void __iomem *base = intc->cpu_base;
	unsigned int cpu_mask, cpu = smp_processor_id();
	int i;

	/*
	 * Get what the GIC says our CPU mask is.
	 */
	BUG_ON(cpu >= NR_HIP04_CPU_IF);
	cpu_mask = hip04_get_cpumask(intc);
	hip04_cpu_map[cpu] = cpu_mask;

	/*
	 * Clear our mask from the other map entries in case they're
	 * still undefined.
	 */
	for (i = 0; i < NR_HIP04_CPU_IF; i++)
		if (i != cpu)
			hip04_cpu_map[i] &= ~cpu_mask;

	gic_cpu_config(dist_base, NULL);

	writel_relaxed(0xf0, base + GIC_CPU_PRIMASK);
	writel_relaxed(1, base + GIC_CPU_CTRL);
}

#ifdef CONFIG_SMP
static void hip04_raise_softirq(const struct cpumask *mask, unsigned int irq)
{
	int cpu;
	unsigned long flags, map = 0;

	raw_spin_lock_irqsave(&irq_controller_lock, flags);

	/* Convert our logical CPU mask into a physical one. */
	for_each_cpu(cpu, mask)
		map |= hip04_cpu_map[cpu];

	/*
	 * Ensure that stores to Normal memory are visible to the
	 * other CPUs before they observe us issuing the IPI.
	 */
	dmb(ishst);

	/* this always happens on GIC0 */
	writel_relaxed(map << 8 | irq, hip04_data.dist_base + GIC_DIST_SOFTINT);

	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
}
#endif

static int hip04_irq_domain_map(struct irq_domain *d, unsigned int irq,
				irq_hw_number_t hw)
{
	if (hw < 32) {
		irq_set_percpu_devid(irq);
		irq_set_chip_and_handler(irq, &hip04_irq_chip,
					 handle_percpu_devid_irq);
		set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
	} else {
		irq_set_chip_and_handler(irq, &hip04_irq_chip,
					 handle_fasteoi_irq);
		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
	}
	irq_set_chip_data(irq, d->host_data);
	return 0;
}

static int hip04_irq_domain_xlate(struct irq_domain *d,
				  struct device_node *controller,
				  const u32 *intspec, unsigned int intsize,
				  unsigned long *out_hwirq,
				  unsigned int *out_type)
{
	unsigned long ret = 0;

	if (d->of_node != controller)
		return -EINVAL;
	if (intsize < 3)
		return -EINVAL;

	/* Get the interrupt number and add 16 to skip over SGIs */
	*out_hwirq = intspec[1] + 16;

	/* For SPIs, we need to add 16 more to get the irq ID number */
	if (!intspec[0])
		*out_hwirq += 16;

	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;

	return ret;
}

#ifdef CONFIG_SMP
static int hip04_irq_secondary_init(struct notifier_block *nfb,
				    unsigned long action,
				    void *hcpu)
{
	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
		hip04_irq_cpu_init(&hip04_data);
	return NOTIFY_OK;
}

/*
 * Notifier for enabling the INTC CPU interface. Set an arbitrarily high
 * priority because the GIC needs to be up before the ARM generic timers.
 */
static struct notifier_block hip04_irq_cpu_notifier = {
	.notifier_call	= hip04_irq_secondary_init,
	.priority	= 100,
};
#endif

static const struct irq_domain_ops hip04_irq_domain_ops = {
	.map	= hip04_irq_domain_map,
	.xlate	= hip04_irq_domain_xlate,
};

static int __init
hip04_of_init(struct device_node *node, struct device_node *parent)
{
	irq_hw_number_t hwirq_base = 16;
	int nr_irqs, irq_base, i;

	if (WARN_ON(!node))
		return -ENODEV;

	hip04_data.dist_base = of_iomap(node, 0);
	WARN(!hip04_data.dist_base, "fail to map hip04 intc dist registers\n");

	hip04_data.cpu_base = of_iomap(node, 1);
	WARN(!hip04_data.cpu_base, "unable to map hip04 intc cpu registers\n");

	/*
	 * Initialize the CPU interface map to all CPUs.
	 * It will be refined as each CPU probes its ID.
	 */
	for (i = 0; i < NR_HIP04_CPU_IF; i++)
		hip04_cpu_map[i] = 0xff;

	/*
	 * Find out how many interrupts are supported.
	 * The HIP04 INTC only supports up to 510 interrupt sources.
	 */
	nr_irqs = readl_relaxed(hip04_data.dist_base + GIC_DIST_CTR) & 0x1f;
	nr_irqs = (nr_irqs + 1) * 32;
	if (nr_irqs > HIP04_MAX_IRQS)
		nr_irqs = HIP04_MAX_IRQS;
	hip04_data.nr_irqs = nr_irqs;

	nr_irqs -= hwirq_base; /* calculate # of irqs to allocate */

	irq_base = irq_alloc_descs(-1, hwirq_base, nr_irqs, numa_node_id());
	if (IS_ERR_VALUE(irq_base)) {
		pr_err("failed to allocate IRQ numbers\n");
		return -EINVAL;
	}

	hip04_data.domain = irq_domain_add_legacy(node, nr_irqs, irq_base,
						  hwirq_base,
						  &hip04_irq_domain_ops,
						  &hip04_data);

	if (WARN_ON(!hip04_data.domain))
		return -EINVAL;

#ifdef CONFIG_SMP
	set_smp_cross_call(hip04_raise_softirq);
	register_cpu_notifier(&hip04_irq_cpu_notifier);
#endif
	set_handle_irq(hip04_handle_irq);

	hip04_irq_dist_init(&hip04_data);
	hip04_irq_cpu_init(&hip04_data);

	return 0;
}
IRQCHIP_DECLARE(hip04_intc, "hisilicon,hip04-intc", hip04_of_init);
OpenPOWER on IntegriCloud