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