1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * ACPI GSI IRQ layer 4 * 5 * Copyright (C) 2015 ARM Ltd. 6 * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> 7 */ 8#include <linux/acpi.h> 9#include <linux/irq.h> 10#include <linux/irqdomain.h> 11#include <linux/of.h> 12 13enum acpi_irq_model_id acpi_irq_model; 14 15static struct fwnode_handle *acpi_gsi_domain_id; 16 17/** 18 * acpi_gsi_to_irq() - Retrieve the linux irq number for a given GSI 19 * @gsi: GSI IRQ number to map 20 * @irq: pointer where linux IRQ number is stored 21 * 22 * irq location updated with irq value [>0 on success, 0 on failure] 23 * 24 * Returns: 0 on success 25 * -EINVAL on failure 26 */ 27int acpi_gsi_to_irq(u32 gsi, unsigned int *irq) 28{ 29 struct irq_domain *d = irq_find_matching_fwnode(acpi_gsi_domain_id, 30 DOMAIN_BUS_ANY); 31 32 *irq = irq_find_mapping(d, gsi); 33 /* 34 * *irq == 0 means no mapping, that should 35 * be reported as a failure 36 */ 37 return (*irq > 0) ? 0 : -EINVAL; 38} 39EXPORT_SYMBOL_GPL(acpi_gsi_to_irq); 40 41/** 42 * acpi_register_gsi() - Map a GSI to a linux IRQ number 43 * @dev: device for which IRQ has to be mapped 44 * @gsi: GSI IRQ number 45 * @trigger: trigger type of the GSI number to be mapped 46 * @polarity: polarity of the GSI to be mapped 47 * 48 * Returns: a valid linux IRQ number on success 49 * -EINVAL on failure 50 */ 51int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, 52 int polarity) 53{ 54 struct irq_fwspec fwspec; 55 unsigned int irq; 56 57 if (WARN_ON(!acpi_gsi_domain_id)) { 58 pr_warn("GSI: No registered irqchip, giving up\n"); 59 return -EINVAL; 60 } 61 62 fwspec.fwnode = acpi_gsi_domain_id; 63 fwspec.param[0] = gsi; 64 fwspec.param[1] = acpi_dev_get_irq_type(trigger, polarity); 65 fwspec.param_count = 2; 66 67 irq = irq_create_fwspec_mapping(&fwspec); 68 if (!irq) 69 return -EINVAL; 70 71 return irq; 72} 73EXPORT_SYMBOL_GPL(acpi_register_gsi); 74 75/** 76 * acpi_unregister_gsi() - Free a GSI<->linux IRQ number mapping 77 * @gsi: GSI IRQ number 78 */ 79void acpi_unregister_gsi(u32 gsi) 80{ 81 struct irq_domain *d = irq_find_matching_fwnode(acpi_gsi_domain_id, 82 DOMAIN_BUS_ANY); 83 int irq = irq_find_mapping(d, gsi); 84 85 irq_dispose_mapping(irq); 86} 87EXPORT_SYMBOL_GPL(acpi_unregister_gsi); 88 89/** 90 * acpi_get_irq_source_fwhandle() - Retrieve fwhandle from IRQ resource source. 91 * @source: acpi_resource_source to use for the lookup. 92 * 93 * Description: 94 * Retrieve the fwhandle of the device referenced by the given IRQ resource 95 * source. 96 * 97 * Return: 98 * The referenced device fwhandle or NULL on failure 99 */ 100static struct fwnode_handle * 101acpi_get_irq_source_fwhandle(const struct acpi_resource_source *source) 102{ 103 struct fwnode_handle *result; 104 struct acpi_device *device; 105 acpi_handle handle; 106 acpi_status status; 107 108 if (!source->string_length) 109 return acpi_gsi_domain_id; 110 111 status = acpi_get_handle(NULL, source->string_ptr, &handle); 112 if (WARN_ON(ACPI_FAILURE(status))) 113 return NULL; 114 115 device = acpi_bus_get_acpi_device(handle); 116 if (WARN_ON(!device)) 117 return NULL; 118 119 result = &device->fwnode; 120 acpi_bus_put_acpi_device(device); 121 return result; 122} 123 124/* 125 * Context for the resource walk used to lookup IRQ resources. 126 * Contains a return code, the lookup index, and references to the flags 127 * and fwspec where the result is returned. 128 */ 129struct acpi_irq_parse_one_ctx { 130 int rc; 131 unsigned int index; 132 unsigned long *res_flags; 133 struct irq_fwspec *fwspec; 134}; 135 136/** 137 * acpi_irq_parse_one_match - Handle a matching IRQ resource. 138 * @fwnode: matching fwnode 139 * @hwirq: hardware IRQ number 140 * @triggering: triggering attributes of hwirq 141 * @polarity: polarity attributes of hwirq 142 * @polarity: polarity attributes of hwirq 143 * @shareable: shareable attributes of hwirq 144 * @ctx: acpi_irq_parse_one_ctx updated by this function 145 * 146 * Description: 147 * Handle a matching IRQ resource by populating the given ctx with 148 * the information passed. 149 */ 150static inline void acpi_irq_parse_one_match(struct fwnode_handle *fwnode, 151 u32 hwirq, u8 triggering, 152 u8 polarity, u8 shareable, 153 struct acpi_irq_parse_one_ctx *ctx) 154{ 155 if (!fwnode) 156 return; 157 ctx->rc = 0; 158 *ctx->res_flags = acpi_dev_irq_flags(triggering, polarity, shareable); 159 ctx->fwspec->fwnode = fwnode; 160 ctx->fwspec->param[0] = hwirq; 161 ctx->fwspec->param[1] = acpi_dev_get_irq_type(triggering, polarity); 162 ctx->fwspec->param_count = 2; 163} 164 165/** 166 * acpi_irq_parse_one_cb - Handle the given resource. 167 * @ares: resource to handle 168 * @context: context for the walk 169 * 170 * Description: 171 * This is called by acpi_walk_resources passing each resource returned by 172 * the _CRS method. We only inspect IRQ resources. Since IRQ resources 173 * might contain multiple interrupts we check if the index is within this 174 * one's interrupt array, otherwise we subtract the current resource IRQ 175 * count from the lookup index to prepare for the next resource. 176 * Once a match is found we call acpi_irq_parse_one_match to populate 177 * the result and end the walk by returning AE_CTRL_TERMINATE. 178 * 179 * Return: 180 * AE_OK if the walk should continue, AE_CTRL_TERMINATE if a matching 181 * IRQ resource was found. 182 */ 183static acpi_status acpi_irq_parse_one_cb(struct acpi_resource *ares, 184 void *context) 185{ 186 struct acpi_irq_parse_one_ctx *ctx = context; 187 struct acpi_resource_irq *irq; 188 struct acpi_resource_extended_irq *eirq; 189 struct fwnode_handle *fwnode; 190 191 switch (ares->type) { 192 case ACPI_RESOURCE_TYPE_IRQ: 193 irq = &ares->data.irq; 194 if (ctx->index >= irq->interrupt_count) { 195 ctx->index -= irq->interrupt_count; 196 return AE_OK; 197 } 198 fwnode = acpi_gsi_domain_id; 199 acpi_irq_parse_one_match(fwnode, irq->interrupts[ctx->index], 200 irq->triggering, irq->polarity, 201 irq->shareable, ctx); 202 return AE_CTRL_TERMINATE; 203 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ: 204 eirq = &ares->data.extended_irq; 205 if (eirq->producer_consumer == ACPI_PRODUCER) 206 return AE_OK; 207 if (ctx->index >= eirq->interrupt_count) { 208 ctx->index -= eirq->interrupt_count; 209 return AE_OK; 210 } 211 fwnode = acpi_get_irq_source_fwhandle(&eirq->resource_source); 212 acpi_irq_parse_one_match(fwnode, eirq->interrupts[ctx->index], 213 eirq->triggering, eirq->polarity, 214 eirq->shareable, ctx); 215 return AE_CTRL_TERMINATE; 216 } 217 218 return AE_OK; 219} 220 221/** 222 * acpi_irq_parse_one - Resolve an interrupt for a device 223 * @handle: the device whose interrupt is to be resolved 224 * @index: index of the interrupt to resolve 225 * @fwspec: structure irq_fwspec filled by this function 226 * @flags: resource flags filled by this function 227 * 228 * Description: 229 * Resolves an interrupt for a device by walking its CRS resources to find 230 * the appropriate ACPI IRQ resource and populating the given struct irq_fwspec 231 * and flags. 232 * 233 * Return: 234 * The result stored in ctx.rc by the callback, or the default -EINVAL value 235 * if an error occurs. 236 */ 237static int acpi_irq_parse_one(acpi_handle handle, unsigned int index, 238 struct irq_fwspec *fwspec, unsigned long *flags) 239{ 240 struct acpi_irq_parse_one_ctx ctx = { -EINVAL, index, flags, fwspec }; 241 242 acpi_walk_resources(handle, METHOD_NAME__CRS, acpi_irq_parse_one_cb, &ctx); 243 return ctx.rc; 244} 245 246/** 247 * acpi_irq_get - Lookup an ACPI IRQ resource and use it to initialize resource. 248 * @handle: ACPI device handle 249 * @index: ACPI IRQ resource index to lookup 250 * @res: Linux IRQ resource to initialize 251 * 252 * Description: 253 * Look for the ACPI IRQ resource with the given index and use it to initialize 254 * the given Linux IRQ resource. 255 * 256 * Return: 257 * 0 on success 258 * -EINVAL if an error occurs 259 * -EPROBE_DEFER if the IRQ lookup/conversion failed 260 */ 261int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res) 262{ 263 struct irq_fwspec fwspec; 264 struct irq_domain *domain; 265 unsigned long flags; 266 int rc; 267 268 rc = acpi_irq_parse_one(handle, index, &fwspec, &flags); 269 if (rc) 270 return rc; 271 272 domain = irq_find_matching_fwnode(fwspec.fwnode, DOMAIN_BUS_ANY); 273 if (!domain) 274 return -EPROBE_DEFER; 275 276 rc = irq_create_fwspec_mapping(&fwspec); 277 if (rc <= 0) 278 return -EINVAL; 279 280 res->start = rc; 281 res->end = rc; 282 res->flags = flags; 283 284 return 0; 285} 286EXPORT_SYMBOL_GPL(acpi_irq_get); 287 288/** 289 * acpi_set_irq_model - Setup the GSI irqdomain information 290 * @model: the value assigned to acpi_irq_model 291 * @fwnode: the irq_domain identifier for mapping and looking up 292 * GSI interrupts 293 */ 294void __init acpi_set_irq_model(enum acpi_irq_model_id model, 295 struct fwnode_handle *fwnode) 296{ 297 acpi_irq_model = model; 298 acpi_gsi_domain_id = fwnode; 299} 300 301/** 302 * acpi_irq_create_hierarchy - Create a hierarchical IRQ domain with the default 303 * GSI domain as its parent. 304 * @flags: Irq domain flags associated with the domain 305 * @size: Size of the domain. 306 * @fwnode: Optional fwnode of the interrupt controller 307 * @ops: Pointer to the interrupt domain callbacks 308 * @host_data: Controller private data pointer 309 */ 310struct irq_domain *acpi_irq_create_hierarchy(unsigned int flags, 311 unsigned int size, 312 struct fwnode_handle *fwnode, 313 const struct irq_domain_ops *ops, 314 void *host_data) 315{ 316 struct irq_domain *d = irq_find_matching_fwnode(acpi_gsi_domain_id, 317 DOMAIN_BUS_ANY); 318 319 if (!d) 320 return NULL; 321 322 return irq_domain_create_hierarchy(d, flags, size, fwnode, ops, 323 host_data); 324} 325EXPORT_SYMBOL_GPL(acpi_irq_create_hierarchy); 326