aboutsummaryrefslogtreecommitdiff
path: root/drivers/irqchip/irq-armada-370-xp.c
blob: a51ee009ed83b4b51249e9b93abd128e4a50d517 (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
/*
 * Marvell Armada 370 and Armada XP SoC IRQ handling
 *
 * Copyright (C) 2012 Marvell
 *
 * Lior Amsalem <alior@marvell.com>
 * Gregory CLEMENT <gregory.clement@free-electrons.com>
 * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
 * Ben Dooks <ben.dooks@codethink.co.uk>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2.  This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/irqdomain.h>
#include <asm/mach/arch.h>
#include <asm/exception.h>
#include <asm/smp_plat.h>
#include <asm/mach/irq.h>

#include "irqchip.h"

/* Interrupt Controller Registers Map */
#define ARMADA_370_XP_INT_SET_MASK_OFFS		(0x48)
#define ARMADA_370_XP_INT_CLEAR_MASK_OFFS	(0x4C)

#define ARMADA_370_XP_INT_CONTROL		(0x00)
#define ARMADA_370_XP_INT_SET_ENABLE_OFFS	(0x30)
#define ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS	(0x34)
#define ARMADA_370_XP_INT_SOURCE_CTL(irq)	(0x100 + irq*4)

#define ARMADA_370_XP_CPU_INTACK_OFFS		(0x44)

#define ARMADA_370_XP_SW_TRIG_INT_OFFS           (0x4)
#define ARMADA_370_XP_IN_DRBEL_MSK_OFFS          (0xc)
#define ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS        (0x8)

#define ARMADA_370_XP_MAX_PER_CPU_IRQS		(28)

#define ARMADA_370_XP_TIMER0_PER_CPU_IRQ	(5)

#define IPI_DOORBELL_START                      (0)
#define IPI_DOORBELL_END                        (8)
#define IPI_DOORBELL_MASK                       0xFF

static DEFINE_RAW_SPINLOCK(irq_controller_lock);

static void __iomem *per_cpu_int_base;
static void __iomem *main_int_base;
static struct irq_domain *armada_370_xp_mpic_domain;

/*
 * In SMP mode:
 * For shared global interrupts, mask/unmask global enable bit
 * For CPU interrupts, mask/unmask the calling CPU's bit
 */
static void armada_370_xp_irq_mask(struct irq_data *d)
{
	irq_hw_number_t hwirq = irqd_to_hwirq(d);

	if (hwirq != ARMADA_370_XP_TIMER0_PER_CPU_IRQ)
		writel(hwirq, main_int_base +
				ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS);
	else
		writel(hwirq, per_cpu_int_base +
				ARMADA_370_XP_INT_SET_MASK_OFFS);
}

static void armada_370_xp_irq_unmask(struct irq_data *d)
{
	irq_hw_number_t hwirq = irqd_to_hwirq(d);

	if (hwirq != ARMADA_370_XP_TIMER0_PER_CPU_IRQ)
		writel(hwirq, main_int_base +
				ARMADA_370_XP_INT_SET_ENABLE_OFFS);
	else
		writel(hwirq, per_cpu_int_base +
				ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
}

#ifdef CONFIG_SMP
static int armada_xp_set_affinity(struct irq_data *d,
				  const struct cpumask *mask_val, bool force)
{
	unsigned long reg;
	unsigned long new_mask = 0;
	unsigned long online_mask = 0;
	unsigned long count = 0;
	irq_hw_number_t hwirq = irqd_to_hwirq(d);
	int cpu;

	for_each_cpu(cpu, mask_val) {
		new_mask |= 1 << cpu_logical_map(cpu);
		count++;
	}

	/*
	 * Forbid mutlicore interrupt affinity
	 * This is required since the MPIC HW doesn't limit
	 * several CPUs from acknowledging the same interrupt.
	 */
	if (count > 1)
		return -EINVAL;

	for_each_cpu(cpu, cpu_online_mask)
		online_mask |= 1 << cpu_logical_map(cpu);

	raw_spin_lock(&irq_controller_lock);

	reg = readl(main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
	reg = (reg & (~online_mask)) | new_mask;
	writel(reg, main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));

	raw_spin_unlock(&irq_controller_lock);

	return 0;
}
#endif

static struct irq_chip armada_370_xp_irq_chip = {
	.name		= "armada_370_xp_irq",
	.irq_mask       = armada_370_xp_irq_mask,
	.irq_mask_ack   = armada_370_xp_irq_mask,
	.irq_unmask     = armada_370_xp_irq_unmask,
#ifdef CONFIG_SMP
	.irq_set_affinity = armada_xp_set_affinity,
#endif
};

static int armada_370_xp_mpic_irq_map(struct irq_domain *h,
				      unsigned int virq, irq_hw_number_t hw)
{
	armada_370_xp_irq_mask(irq_get_irq_data(virq));
	if (hw != ARMADA_370_XP_TIMER0_PER_CPU_IRQ)
		writel(hw, per_cpu_int_base +
			ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
	else
		writel(hw, main_int_base + ARMADA_370_XP_INT_SET_ENABLE_OFFS);
	irq_set_status_flags(virq, IRQ_LEVEL);

	if (hw == ARMADA_370_XP_TIMER0_PER_CPU_IRQ) {
		irq_set_percpu_devid(virq);
		irq_set_chip_and_handler(virq, &armada_370_xp_irq_chip,
					handle_percpu_devid_irq);

	} else {
		irq_set_chip_and_handler(virq, &armada_370_xp_irq_chip,
					handle_level_irq);
	}
	set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);

	return 0;
}

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

	/* Convert our logical CPU mask into a physical one. */
	for_each_cpu(cpu, mask)
		map |= 1 << cpu_logical_map(cpu);

	/*
	 * Ensure that stores to Normal memory are visible to the
	 * other CPUs before issuing the IPI.
	 */
	dsb();

	/* submit softirq */
	writel((map << 8) | irq, main_int_base +
		ARMADA_370_XP_SW_TRIG_INT_OFFS);
}

void armada_xp_mpic_smp_cpu_init(void)
{
	/* Clear pending IPIs */
	writel(0, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);

	/* Enable first 8 IPIs */
	writel(IPI_DOORBELL_MASK, per_cpu_int_base +
		ARMADA_370_XP_IN_DRBEL_MSK_OFFS);

	/* Unmask IPI interrupt */
	writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
}
#endif /* CONFIG_SMP */

static struct irq_domain_ops armada_370_xp_mpic_irq_ops = {
	.map = armada_370_xp_mpic_irq_map,
	.xlate = irq_domain_xlate_onecell,
};

static asmlinkage void __exception_irq_entry
armada_370_xp_handle_irq(struct pt_regs *regs)
{
	u32 irqstat, irqnr;

	do {
		irqstat = readl_relaxed(per_cpu_int_base +
					ARMADA_370_XP_CPU_INTACK_OFFS);
		irqnr = irqstat & 0x3FF;

		if (irqnr > 1022)
			break;

		if (irqnr > 0) {
			irqnr =	irq_find_mapping(armada_370_xp_mpic_domain,
					irqnr);
			handle_IRQ(irqnr, regs);
			continue;
		}
#ifdef CONFIG_SMP
		/* IPI Handling */
		if (irqnr == 0) {
			u32 ipimask, ipinr;

			ipimask = readl_relaxed(per_cpu_int_base +
						ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
				& IPI_DOORBELL_MASK;

			writel(~ipimask, per_cpu_int_base +
				ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);

			/* Handle all pending doorbells */
			for (ipinr = IPI_DOORBELL_START;
			     ipinr < IPI_DOORBELL_END; ipinr++) {
				if (ipimask & (0x1 << ipinr))
					handle_IPI(ipinr, regs);
			}
			continue;
		}
#endif

	} while (1);
}

static int __init armada_370_xp_mpic_of_init(struct device_node *node,
					     struct device_node *parent)
{
	u32 control;

	main_int_base = of_iomap(node, 0);
	per_cpu_int_base = of_iomap(node, 1);

	BUG_ON(!main_int_base);
	BUG_ON(!per_cpu_int_base);

	control = readl(main_int_base + ARMADA_370_XP_INT_CONTROL);

	armada_370_xp_mpic_domain =
		irq_domain_add_linear(node, (control >> 2) & 0x3ff,
				&armada_370_xp_mpic_irq_ops, NULL);

	if (!armada_370_xp_mpic_domain)
		panic("Unable to add Armada_370_Xp MPIC irq domain (DT)\n");

	irq_set_default_host(armada_370_xp_mpic_domain);

#ifdef CONFIG_SMP
	armada_xp_mpic_smp_cpu_init();

	/*
	 * Set the default affinity from all CPUs to the boot cpu.
	 * This is required since the MPIC doesn't limit several CPUs
	 * from acknowledging the same interrupt.
	 */
	cpumask_clear(irq_default_affinity);
	cpumask_set_cpu(smp_processor_id(), irq_default_affinity);

#endif

	set_handle_irq(armada_370_xp_handle_irq);

	return 0;
}

IRQCHIP_DECLARE(armada_370_xp_mpic, "marvell,mpic", armada_370_xp_mpic_of_init);