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 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 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 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 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 } 135 136 137 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 143 static inline void its_fsl_mc_acpi_msi_init(void) { } 144 #endif 145 146 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 } 161 162 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