summaryrefslogtreecommitdiffstats
path: root/drivers/irqchip/irq-gic-v3-its-platform-msi.c
blob: 8881a053c173edfdb11ad322b9b60f9b61ef57aa (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
/*
 * Copyright (C) 2013-2015 ARM Limited, All Rights Reserved.
 * Author: Marc Zyngier <marc.zyngier@arm.com>
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/acpi_iort.h>
#include <linux/device.h>
#include <linux/msi.h>
#include <linux/of.h>
#include <linux/of_irq.h>

static struct irq_chip its_pmsi_irq_chip = {
	.name			= "ITS-pMSI",
};

static int of_pmsi_get_dev_id(struct irq_domain *domain, struct device *dev,
				  u32 *dev_id)
{
	int ret, index = 0;

	/* Suck the DeviceID out of the msi-parent property */
	do {
		struct of_phandle_args args;

		ret = of_parse_phandle_with_args(dev->of_node,
						 "msi-parent", "#msi-cells",
						 index, &args);
		if (args.np == irq_domain_get_of_node(domain)) {
			if (WARN_ON(args.args_count != 1))
				return -EINVAL;
			*dev_id = args.args[0];
			break;
		}
		index++;
	} while (!ret);

	return ret;
}

int __weak iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id)
{
	return -1;
}

static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
			    int nvec, msi_alloc_info_t *info)
{
	struct msi_domain_info *msi_info;
	u32 dev_id;
	int ret;

	msi_info = msi_get_domain_info(domain->parent);

	if (dev->of_node)
		ret = of_pmsi_get_dev_id(domain, dev, &dev_id);
	else
		ret = iort_pmsi_get_dev_id(dev, &dev_id);
	if (ret)
		return ret;

	/* ITS specific DeviceID, as the core ITS ignores dev. */
	info->scratchpad[0].ul = dev_id;

	return msi_info->ops->msi_prepare(domain->parent,
					  dev, nvec, info);
}

static struct msi_domain_ops its_pmsi_ops = {
	.msi_prepare	= its_pmsi_prepare,
};

static struct msi_domain_info its_pmsi_domain_info = {
	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
	.ops	= &its_pmsi_ops,
	.chip	= &its_pmsi_irq_chip,
};

static const struct of_device_id its_device_id[] = {
	{	.compatible	= "arm,gic-v3-its",	},
	{},
};

static int __init its_pmsi_init_one(struct fwnode_handle *fwnode,
				const char *name)
{
	struct irq_domain *parent;

	parent = irq_find_matching_fwnode(fwnode, DOMAIN_BUS_NEXUS);
	if (!parent || !msi_get_domain_info(parent)) {
		pr_err("%s: unable to locate ITS domain\n", name);
		return -ENXIO;
	}

	if (!platform_msi_create_irq_domain(fwnode, &its_pmsi_domain_info,
					    parent)) {
		pr_err("%s: unable to create platform domain\n", name);
		return -ENXIO;
	}

	pr_info("Platform MSI: %s domain created\n", name);
	return 0;
}

#ifdef CONFIG_ACPI
static int __init
its_pmsi_parse_madt(struct acpi_subtable_header *header,
			const unsigned long end)
{
	struct acpi_madt_generic_translator *its_entry;
	struct fwnode_handle *domain_handle;
	const char *node_name;
	int err = -ENXIO;

	its_entry = (struct acpi_madt_generic_translator *)header;
	node_name = kasprintf(GFP_KERNEL, "ITS@0x%lx",
			      (long)its_entry->base_address);
	domain_handle = iort_find_domain_token(its_entry->translation_id);
	if (!domain_handle) {
		pr_err("%s: Unable to locate ITS domain handle\n", node_name);
		goto out;
	}

	err = its_pmsi_init_one(domain_handle, node_name);

out:
	kfree(node_name);
	return err;
}

static void __init its_pmsi_acpi_init(void)
{
	acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_TRANSLATOR,
			      its_pmsi_parse_madt, 0);
}
#else
static inline void its_pmsi_acpi_init(void) { }
#endif

static void __init its_pmsi_of_init(void)
{
	struct device_node *np;

	for (np = of_find_matching_node(NULL, its_device_id); np;
	     np = of_find_matching_node(np, its_device_id)) {
		if (!of_device_is_available(np))
			continue;
		if (!of_property_read_bool(np, "msi-controller"))
			continue;

		its_pmsi_init_one(of_node_to_fwnode(np), np->full_name);
	}
}

static int __init its_pmsi_init(void)
{
	its_pmsi_of_init();
	its_pmsi_acpi_init();
	return 0;
}
early_initcall(its_pmsi_init);
OpenPOWER on IntegriCloud