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(domain); 33 out_id = of_node ? of_msi_map_id(&mc_dev->dev, of_node, mc_dev->icid) : 34 iort_msi_map_id(&mc_dev->dev, 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(msi_domain, 60 mc_bus_dev); 61 msi_info = msi_get_domain_info(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(handle, DOMAIN_BUS_NEXUS); 90 if (!parent || !msi_get_domain_info(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(handle, 96 &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 *header, 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, "ITS@0x%lx", 118 (long)its_entry->base_address); 119 120 dom_handle = iort_find_domain_token(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(dom_handle, node_name); 128 129 out: 130 kfree(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(ACPI_MADT_TYPE_GENERIC_TRANSLATOR, 138 its_fsl_mc_msi_parse_madt, 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, its_device_id); np; 149 np = of_find_matching_node(np, its_device_id)) { 150 if (!of_device_is_available(np)) 151 continue; 152 if (!of_property_read_bool(np, "msi-controller")) 153 continue; 154 155 its_fsl_mc_msi_init_one(of_node_to_fwnode(np), 156 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