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/of_device.h> 11 #include <linux/of_address.h> 12 #include <linux/of_irq.h> 13 #include <linux/irq.h> 14 #include <linux/irqdomain.h> 15 #include <linux/msi.h> 16 #include <linux/acpi_iort.h> 17 18 #include "fsl-mc-private.h" 19 20 #ifdef GENERIC_MSI_DOMAIN_OPS 21 /* 22 * Generate a unique ID identifying the interrupt (only used within the MSI 23 * irqdomain. Combine the icid with the interrupt index. 24 */ 25 static irq_hw_number_t fsl_mc_domain_calc_hwirq(struct fsl_mc_device *dev, 26 struct msi_desc *desc) 27 { 28 /* 29 * Make the base hwirq value for ICID*10000 so it is readable 30 * as a decimal value in /proc/interrupts. 31 */ 32 return (irq_hw_number_t)(desc->fsl_mc.msi_index + (dev->icid * 10000)); 33 } 34 35 static void fsl_mc_msi_set_desc(msi_alloc_info_t *arg, 36 struct msi_desc *desc) 37 { 38 arg->desc = desc; 39 arg->hwirq = fsl_mc_domain_calc_hwirq(to_fsl_mc_device(desc->dev), 40 desc); 41 } 42 #else 43 #define fsl_mc_msi_set_desc NULL 44 #endif 45 46 static void fsl_mc_msi_update_dom_ops(struct msi_domain_info *info) 47 { 48 struct msi_domain_ops *ops = info->ops; 49 50 if (!ops) 51 return; 52 53 /* 54 * set_desc should not be set by the caller 55 */ 56 if (!ops->set_desc) 57 ops->set_desc = fsl_mc_msi_set_desc; 58 } 59 60 static void __fsl_mc_msi_write_msg(struct fsl_mc_device *mc_bus_dev, 61 struct fsl_mc_device_irq *mc_dev_irq) 62 { 63 int error; 64 struct fsl_mc_device *owner_mc_dev = mc_dev_irq->mc_dev; 65 struct msi_desc *msi_desc = mc_dev_irq->msi_desc; 66 struct dprc_irq_cfg irq_cfg; 67 68 /* 69 * msi_desc->msg.address is 0x0 when this function is invoked in 70 * the free_irq() code path. In this case, for the MC, we don't 71 * really need to "unprogram" the MSI, so we just return. 72 */ 73 if (msi_desc->msg.address_lo == 0x0 && msi_desc->msg.address_hi == 0x0) 74 return; 75 76 if (!owner_mc_dev) 77 return; 78 79 irq_cfg.paddr = ((u64)msi_desc->msg.address_hi << 32) | 80 msi_desc->msg.address_lo; 81 irq_cfg.val = msi_desc->msg.data; 82 irq_cfg.irq_num = msi_desc->irq; 83 84 if (owner_mc_dev == mc_bus_dev) { 85 /* 86 * IRQ is for the mc_bus_dev's DPRC itself 87 */ 88 error = dprc_set_irq(mc_bus_dev->mc_io, 89 MC_CMD_FLAG_INTR_DIS | MC_CMD_FLAG_PRI, 90 mc_bus_dev->mc_handle, 91 mc_dev_irq->dev_irq_index, 92 &irq_cfg); 93 if (error < 0) { 94 dev_err(&owner_mc_dev->dev, 95 "dprc_set_irq() failed: %d\n", error); 96 } 97 } else { 98 /* 99 * IRQ is for for a child device of mc_bus_dev 100 */ 101 error = dprc_set_obj_irq(mc_bus_dev->mc_io, 102 MC_CMD_FLAG_INTR_DIS | MC_CMD_FLAG_PRI, 103 mc_bus_dev->mc_handle, 104 owner_mc_dev->obj_desc.type, 105 owner_mc_dev->obj_desc.id, 106 mc_dev_irq->dev_irq_index, 107 &irq_cfg); 108 if (error < 0) { 109 dev_err(&owner_mc_dev->dev, 110 "dprc_obj_set_irq() failed: %d\n", error); 111 } 112 } 113 } 114 115 /* 116 * NOTE: This function is invoked with interrupts disabled 117 */ 118 static void fsl_mc_msi_write_msg(struct irq_data *irq_data, 119 struct msi_msg *msg) 120 { 121 struct msi_desc *msi_desc = irq_data_get_msi_desc(irq_data); 122 struct fsl_mc_device *mc_bus_dev = to_fsl_mc_device(msi_desc->dev); 123 struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev); 124 struct fsl_mc_device_irq *mc_dev_irq = 125 &mc_bus->irq_resources[msi_desc->fsl_mc.msi_index]; 126 127 msi_desc->msg = *msg; 128 129 /* 130 * Program the MSI (paddr, value) pair in the device: 131 */ 132 __fsl_mc_msi_write_msg(mc_bus_dev, mc_dev_irq); 133 } 134 135 static void fsl_mc_msi_update_chip_ops(struct msi_domain_info *info) 136 { 137 struct irq_chip *chip = info->chip; 138 139 if (!chip) 140 return; 141 142 /* 143 * irq_write_msi_msg should not be set by the caller 144 */ 145 if (!chip->irq_write_msi_msg) 146 chip->irq_write_msi_msg = fsl_mc_msi_write_msg; 147 } 148 149 /** 150 * fsl_mc_msi_create_irq_domain - Create a fsl-mc MSI interrupt domain 151 * @np: Optional device-tree node of the interrupt controller 152 * @info: MSI domain info 153 * @parent: Parent irq domain 154 * 155 * Updates the domain and chip ops and creates a fsl-mc MSI 156 * interrupt domain. 157 * 158 * Returns: 159 * A domain pointer or NULL in case of failure. 160 */ 161 struct irq_domain *fsl_mc_msi_create_irq_domain(struct fwnode_handle *fwnode, 162 struct msi_domain_info *info, 163 struct irq_domain *parent) 164 { 165 struct irq_domain *domain; 166 167 if (WARN_ON((info->flags & MSI_FLAG_LEVEL_CAPABLE))) 168 info->flags &= ~MSI_FLAG_LEVEL_CAPABLE; 169 if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS) 170 fsl_mc_msi_update_dom_ops(info); 171 if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS) 172 fsl_mc_msi_update_chip_ops(info); 173 174 domain = msi_create_irq_domain(fwnode, info, parent); 175 if (domain) 176 irq_domain_update_bus_token(domain, DOMAIN_BUS_FSL_MC_MSI); 177 178 return domain; 179 } 180 181 struct irq_domain *fsl_mc_find_msi_domain(struct device *dev) 182 { 183 struct device *root_dprc_dev; 184 struct device *bus_dev; 185 struct irq_domain *msi_domain; 186 struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev); 187 188 fsl_mc_get_root_dprc(dev, &root_dprc_dev); 189 bus_dev = root_dprc_dev->parent; 190 191 if (bus_dev->of_node) { 192 msi_domain = of_msi_map_get_device_domain(dev, 193 mc_dev->icid, 194 DOMAIN_BUS_FSL_MC_MSI); 195 196 /* 197 * if the msi-map property is missing assume that all the 198 * child containers inherit the domain from the parent 199 */ 200 if (!msi_domain) 201 202 msi_domain = of_msi_get_domain(bus_dev, 203 bus_dev->of_node, 204 DOMAIN_BUS_FSL_MC_MSI); 205 } else { 206 msi_domain = iort_get_device_domain(dev, mc_dev->icid, 207 DOMAIN_BUS_FSL_MC_MSI); 208 } 209 210 return msi_domain; 211 } 212 213 static void fsl_mc_msi_free_descs(struct device *dev) 214 { 215 struct msi_desc *desc, *tmp; 216 217 list_for_each_entry_safe(desc, tmp, dev_to_msi_list(dev), list) { 218 list_del(&desc->list); 219 free_msi_entry(desc); 220 } 221 } 222 223 static int fsl_mc_msi_alloc_descs(struct device *dev, unsigned int irq_count) 224 225 { 226 unsigned int i; 227 int error; 228 struct msi_desc *msi_desc; 229 230 for (i = 0; i < irq_count; i++) { 231 msi_desc = alloc_msi_entry(dev, 1, NULL); 232 if (!msi_desc) { 233 dev_err(dev, "Failed to allocate msi entry\n"); 234 error = -ENOMEM; 235 goto cleanup_msi_descs; 236 } 237 238 msi_desc->fsl_mc.msi_index = i; 239 INIT_LIST_HEAD(&msi_desc->list); 240 list_add_tail(&msi_desc->list, dev_to_msi_list(dev)); 241 } 242 243 return 0; 244 245 cleanup_msi_descs: 246 fsl_mc_msi_free_descs(dev); 247 return error; 248 } 249 250 int fsl_mc_msi_domain_alloc_irqs(struct device *dev, 251 unsigned int irq_count) 252 { 253 struct irq_domain *msi_domain; 254 int error; 255 256 if (!list_empty(dev_to_msi_list(dev))) 257 return -EINVAL; 258 259 error = fsl_mc_msi_alloc_descs(dev, irq_count); 260 if (error < 0) 261 return error; 262 263 msi_domain = dev_get_msi_domain(dev); 264 if (!msi_domain) { 265 error = -EINVAL; 266 goto cleanup_msi_descs; 267 } 268 269 /* 270 * NOTE: Calling this function will trigger the invocation of the 271 * its_fsl_mc_msi_prepare() callback 272 */ 273 error = msi_domain_alloc_irqs(msi_domain, dev, irq_count); 274 275 if (error) { 276 dev_err(dev, "Failed to allocate IRQs\n"); 277 goto cleanup_msi_descs; 278 } 279 280 return 0; 281 282 cleanup_msi_descs: 283 fsl_mc_msi_free_descs(dev); 284 return error; 285 } 286 287 void fsl_mc_msi_domain_free_irqs(struct device *dev) 288 { 289 struct irq_domain *msi_domain; 290 291 msi_domain = dev_get_msi_domain(dev); 292 if (!msi_domain) 293 return; 294 295 msi_domain_free_irqs(msi_domain, dev); 296 297 if (list_empty(dev_to_msi_list(dev))) 298 return; 299 300 fsl_mc_msi_free_descs(dev); 301 } 302