1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Freescale Management Complex (MC) bus driver MSI support
4 *
5 * Copyright (C) 2015-2016 Freescale Semiconductor, Inc.
6 * Author: German Rivera <German.Rivera@freescale.com>
7 *
8 */
9
10 #include <linux/acpi.h>
11 #include <linux/acpi_iort.h>
12 #include <linux/of_device.h>
13 #include <linux/of_address.h>
14 #include <linux/irq.h>
15 #include <linux/msi.h>
16 #include <linux/of.h>
17 #include <linux/of_irq.h>
18 #include <linux/fsl/mc.h>
19
20 static struct irq_chip its_msi_irq_chip = {
21 .name = "ITS-fMSI",
22 .irq_mask = irq_chip_mask_parent,
23 .irq_unmask = irq_chip_unmask_parent,
24 .irq_eoi = irq_chip_eoi_parent,
25 .irq_set_affinity = msi_domain_set_affinity
26 };
27
fsl_mc_msi_domain_get_msi_id(struct irq_domain * domain,struct fsl_mc_device * mc_dev)28 static u32 fsl_mc_msi_domain_get_msi_id(struct irq_domain *domain,
29 struct fsl_mc_device *mc_dev)
30 {
31 struct device_node *of_node;
32 u32 out_id;
33
34 of_node = irq_domain_get_of_node(domain);
35 out_id = of_node ? of_msi_map_id(&mc_dev->dev, of_node, mc_dev->icid) :
36 iort_msi_map_id(&mc_dev->dev, mc_dev->icid);
37
38 return out_id;
39 }
40
its_fsl_mc_msi_prepare(struct irq_domain * msi_domain,struct device * dev,int nvec,msi_alloc_info_t * info)41 static int its_fsl_mc_msi_prepare(struct irq_domain *msi_domain,
42 struct device *dev,
43 int nvec, msi_alloc_info_t *info)
44 {
45 struct fsl_mc_device *mc_bus_dev;
46 struct msi_domain_info *msi_info;
47
48 if (!dev_is_fsl_mc(dev))
49 return -EINVAL;
50
51 mc_bus_dev = to_fsl_mc_device(dev);
52 if (!(mc_bus_dev->flags & FSL_MC_IS_DPRC))
53 return -EINVAL;
54
55 /*
56 * Set the device Id to be passed to the GIC-ITS:
57 *
58 * NOTE: This device id corresponds to the IOMMU stream ID
59 * associated with the DPRC object (ICID).
60 */
61 info->scratchpad[0].ul = fsl_mc_msi_domain_get_msi_id(msi_domain,
62 mc_bus_dev);
63 msi_info = msi_get_domain_info(msi_domain->parent);
64
65 /* Allocate at least 32 MSIs, and always as a power of 2 */
66 nvec = max_t(int, 32, roundup_pow_of_two(nvec));
67 return msi_info->ops->msi_prepare(msi_domain->parent, dev, nvec, info);
68 }
69
70 static struct msi_domain_ops its_fsl_mc_msi_ops __ro_after_init = {
71 .msi_prepare = its_fsl_mc_msi_prepare,
72 };
73
74 static struct msi_domain_info its_fsl_mc_msi_domain_info = {
75 .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
76 .ops = &its_fsl_mc_msi_ops,
77 .chip = &its_msi_irq_chip,
78 };
79
80 static const struct of_device_id its_device_id[] = {
81 { .compatible = "arm,gic-v3-its", },
82 {},
83 };
84
its_fsl_mc_msi_init_one(struct fwnode_handle * handle,const char * name)85 static void __init its_fsl_mc_msi_init_one(struct fwnode_handle *handle,
86 const char *name)
87 {
88 struct irq_domain *parent;
89 struct irq_domain *mc_msi_domain;
90
91 parent = irq_find_matching_fwnode(handle, DOMAIN_BUS_NEXUS);
92 if (!parent || !msi_get_domain_info(parent)) {
93 pr_err("%s: unable to locate ITS domain\n", name);
94 return;
95 }
96
97 mc_msi_domain = fsl_mc_msi_create_irq_domain(handle,
98 &its_fsl_mc_msi_domain_info,
99 parent);
100 if (!mc_msi_domain) {
101 pr_err("%s: unable to create fsl-mc domain\n", name);
102 return;
103 }
104
105 pr_info("fsl-mc MSI: %s domain created\n", name);
106 }
107
108 #ifdef CONFIG_ACPI
109 static int __init
its_fsl_mc_msi_parse_madt(union acpi_subtable_headers * header,const unsigned long end)110 its_fsl_mc_msi_parse_madt(union acpi_subtable_headers *header,
111 const unsigned long end)
112 {
113 struct acpi_madt_generic_translator *its_entry;
114 struct fwnode_handle *dom_handle;
115 const char *node_name;
116 int err = 0;
117
118 its_entry = (struct acpi_madt_generic_translator *)header;
119 node_name = kasprintf(GFP_KERNEL, "ITS@0x%lx",
120 (long)its_entry->base_address);
121
122 dom_handle = iort_find_domain_token(its_entry->translation_id);
123 if (!dom_handle) {
124 pr_err("%s: Unable to locate ITS domain handle\n", node_name);
125 err = -ENXIO;
126 goto out;
127 }
128
129 its_fsl_mc_msi_init_one(dom_handle, node_name);
130
131 out:
132 kfree(node_name);
133 return err;
134 }
135
136
its_fsl_mc_acpi_msi_init(void)137 static void __init its_fsl_mc_acpi_msi_init(void)
138 {
139 acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_TRANSLATOR,
140 its_fsl_mc_msi_parse_madt, 0);
141 }
142 #else
its_fsl_mc_acpi_msi_init(void)143 static inline void its_fsl_mc_acpi_msi_init(void) { }
144 #endif
145
its_fsl_mc_of_msi_init(void)146 static void __init its_fsl_mc_of_msi_init(void)
147 {
148 struct device_node *np;
149
150 for (np = of_find_matching_node(NULL, its_device_id); np;
151 np = of_find_matching_node(np, its_device_id)) {
152 if (!of_device_is_available(np))
153 continue;
154 if (!of_property_read_bool(np, "msi-controller"))
155 continue;
156
157 its_fsl_mc_msi_init_one(of_node_to_fwnode(np),
158 np->full_name);
159 }
160 }
161
its_fsl_mc_msi_init(void)162 static int __init its_fsl_mc_msi_init(void)
163 {
164 its_fsl_mc_of_msi_init();
165 its_fsl_mc_acpi_msi_init();
166
167 return 0;
168 }
169
170 early_initcall(its_fsl_mc_msi_init);
171