1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2020, Jiaxun Yang <jiaxun.yang@flygoat.com> 4 * Loongson Local IO Interrupt Controller support 5 */ 6 7 #include <linux/errno.h> 8 #include <linux/init.h> 9 #include <linux/types.h> 10 #include <linux/interrupt.h> 11 #include <linux/ioport.h> 12 #include <linux/irqchip.h> 13 #include <linux/of_address.h> 14 #include <linux/of_irq.h> 15 #include <linux/io.h> 16 #include <linux/smp.h> 17 #include <linux/irqchip/chained_irq.h> 18 19 #ifdef CONFIG_MIPS 20 #include <loongson.h> 21 #else 22 #include <asm/loongson.h> 23 #endif 24 25 #define LIOINTC_CHIP_IRQ 32 26 #define LIOINTC_NUM_PARENT 4 27 #define LIOINTC_NUM_CORES 4 28 29 #define LIOINTC_INTC_CHIP_START 0x20 30 31 #define LIOINTC_REG_INTC_STATUS (LIOINTC_INTC_CHIP_START + 0x20) 32 #define LIOINTC_REG_INTC_EN_STATUS (LIOINTC_INTC_CHIP_START + 0x04) 33 #define LIOINTC_REG_INTC_ENABLE (LIOINTC_INTC_CHIP_START + 0x08) 34 #define LIOINTC_REG_INTC_DISABLE (LIOINTC_INTC_CHIP_START + 0x0c) 35 #define LIOINTC_REG_INTC_POL (LIOINTC_INTC_CHIP_START + 0x10) 36 #define LIOINTC_REG_INTC_EDGE (LIOINTC_INTC_CHIP_START + 0x14) 37 38 #define LIOINTC_SHIFT_INTx 4 39 40 #define LIOINTC_ERRATA_IRQ 10 41 42 #if defined(CONFIG_MIPS) 43 #define liointc_core_id get_ebase_cpunum() 44 #else 45 #define liointc_core_id get_csr_cpuid() 46 #endif 47 48 struct liointc_handler_data { 49 struct liointc_priv *priv; 50 u32 parent_int_map; 51 }; 52 53 struct liointc_priv { 54 struct irq_chip_generic *gc; 55 struct liointc_handler_data handler[LIOINTC_NUM_PARENT]; 56 void __iomem *core_isr[LIOINTC_NUM_CORES]; 57 u8 map_cache[LIOINTC_CHIP_IRQ]; 58 bool has_lpc_irq_errata; 59 }; 60 61 struct fwnode_handle *liointc_handle; 62 63 static void liointc_chained_handle_irq(struct irq_desc *desc) 64 { 65 struct liointc_handler_data *handler = irq_desc_get_handler_data(desc); 66 struct irq_chip *chip = irq_desc_get_chip(desc); 67 struct irq_chip_generic *gc = handler->priv->gc; 68 int core = liointc_core_id % LIOINTC_NUM_CORES; 69 u32 pending; 70 71 chained_irq_enter(chip, desc); 72 73 pending = readl(handler->priv->core_isr[core]); 74 75 if (!pending) { 76 /* Always blame LPC IRQ if we have that bug */ 77 if (handler->priv->has_lpc_irq_errata && 78 (handler->parent_int_map & gc->mask_cache & 79 BIT(LIOINTC_ERRATA_IRQ))) 80 pending = BIT(LIOINTC_ERRATA_IRQ); 81 else 82 spurious_interrupt(); 83 } 84 85 while (pending) { 86 int bit = __ffs(pending); 87 88 generic_handle_domain_irq(gc->domain, bit); 89 pending &= ~BIT(bit); 90 } 91 92 chained_irq_exit(chip, desc); 93 } 94 95 static void liointc_set_bit(struct irq_chip_generic *gc, 96 unsigned int offset, 97 u32 mask, bool set) 98 { 99 if (set) 100 writel(readl(gc->reg_base + offset) | mask, 101 gc->reg_base + offset); 102 else 103 writel(readl(gc->reg_base + offset) & ~mask, 104 gc->reg_base + offset); 105 } 106 107 static int liointc_set_type(struct irq_data *data, unsigned int type) 108 { 109 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data); 110 u32 mask = data->mask; 111 unsigned long flags; 112 113 irq_gc_lock_irqsave(gc, flags); 114 switch (type) { 115 case IRQ_TYPE_LEVEL_HIGH: 116 liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, false); 117 liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, true); 118 break; 119 case IRQ_TYPE_LEVEL_LOW: 120 liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, false); 121 liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, false); 122 break; 123 case IRQ_TYPE_EDGE_RISING: 124 liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, true); 125 liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, true); 126 break; 127 case IRQ_TYPE_EDGE_FALLING: 128 liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, true); 129 liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, false); 130 break; 131 default: 132 irq_gc_unlock_irqrestore(gc, flags); 133 return -EINVAL; 134 } 135 irq_gc_unlock_irqrestore(gc, flags); 136 137 irqd_set_trigger_type(data, type); 138 return 0; 139 } 140 141 static void liointc_resume(struct irq_chip_generic *gc) 142 { 143 struct liointc_priv *priv = gc->private; 144 unsigned long flags; 145 int i; 146 147 irq_gc_lock_irqsave(gc, flags); 148 /* Disable all at first */ 149 writel(0xffffffff, gc->reg_base + LIOINTC_REG_INTC_DISABLE); 150 /* Restore map cache */ 151 for (i = 0; i < LIOINTC_CHIP_IRQ; i++) 152 writeb(priv->map_cache[i], gc->reg_base + i); 153 /* Restore mask cache */ 154 writel(gc->mask_cache, gc->reg_base + LIOINTC_REG_INTC_ENABLE); 155 irq_gc_unlock_irqrestore(gc, flags); 156 } 157 158 static int parent_irq[LIOINTC_NUM_PARENT]; 159 static u32 parent_int_map[LIOINTC_NUM_PARENT]; 160 static const char *const parent_names[] = {"int0", "int1", "int2", "int3"}; 161 static const char *const core_reg_names[] = {"isr0", "isr1", "isr2", "isr3"}; 162 163 static int liointc_domain_xlate(struct irq_domain *d, struct device_node *ctrlr, 164 const u32 *intspec, unsigned int intsize, 165 unsigned long *out_hwirq, unsigned int *out_type) 166 { 167 if (WARN_ON(intsize < 1)) 168 return -EINVAL; 169 *out_hwirq = intspec[0] - GSI_MIN_CPU_IRQ; 170 *out_type = IRQ_TYPE_NONE; 171 return 0; 172 } 173 174 static const struct irq_domain_ops acpi_irq_gc_ops = { 175 .map = irq_map_generic_chip, 176 .unmap = irq_unmap_generic_chip, 177 .xlate = liointc_domain_xlate, 178 }; 179 180 static int liointc_init(phys_addr_t addr, unsigned long size, int revision, 181 struct fwnode_handle *domain_handle, struct device_node *node) 182 { 183 int i, err; 184 void __iomem *base; 185 struct irq_chip_type *ct; 186 struct irq_chip_generic *gc; 187 struct irq_domain *domain; 188 struct liointc_priv *priv; 189 190 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 191 if (!priv) 192 return -ENOMEM; 193 194 base = ioremap(addr, size); 195 if (!base) 196 goto out_free_priv; 197 198 for (i = 0; i < LIOINTC_NUM_CORES; i++) 199 priv->core_isr[i] = base + LIOINTC_REG_INTC_STATUS; 200 201 for (i = 0; i < LIOINTC_NUM_PARENT; i++) 202 priv->handler[i].parent_int_map = parent_int_map[i]; 203 204 if (revision > 1) { 205 for (i = 0; i < LIOINTC_NUM_CORES; i++) { 206 int index = of_property_match_string(node, 207 "reg-names", core_reg_names[i]); 208 209 if (index < 0) 210 goto out_iounmap; 211 212 priv->core_isr[i] = of_iomap(node, index); 213 } 214 } 215 216 /* Setup IRQ domain */ 217 if (!acpi_disabled) 218 domain = irq_domain_create_linear(domain_handle, LIOINTC_CHIP_IRQ, 219 &acpi_irq_gc_ops, priv); 220 else 221 domain = irq_domain_create_linear(domain_handle, LIOINTC_CHIP_IRQ, 222 &irq_generic_chip_ops, priv); 223 if (!domain) { 224 pr_err("loongson-liointc: cannot add IRQ domain\n"); 225 goto out_iounmap; 226 } 227 228 err = irq_alloc_domain_generic_chips(domain, LIOINTC_CHIP_IRQ, 1, 229 (node ? node->full_name : "LIOINTC"), 230 handle_level_irq, 0, IRQ_NOPROBE, 0); 231 if (err) { 232 pr_err("loongson-liointc: unable to register IRQ domain\n"); 233 goto out_free_domain; 234 } 235 236 237 /* Disable all IRQs */ 238 writel(0xffffffff, base + LIOINTC_REG_INTC_DISABLE); 239 /* Set to level triggered */ 240 writel(0x0, base + LIOINTC_REG_INTC_EDGE); 241 242 /* Generate parent INT part of map cache */ 243 for (i = 0; i < LIOINTC_NUM_PARENT; i++) { 244 u32 pending = priv->handler[i].parent_int_map; 245 246 while (pending) { 247 int bit = __ffs(pending); 248 249 priv->map_cache[bit] = BIT(i) << LIOINTC_SHIFT_INTx; 250 pending &= ~BIT(bit); 251 } 252 } 253 254 for (i = 0; i < LIOINTC_CHIP_IRQ; i++) { 255 /* Generate core part of map cache */ 256 priv->map_cache[i] |= BIT(loongson_sysconf.boot_cpu_id); 257 writeb(priv->map_cache[i], base + i); 258 } 259 260 gc = irq_get_domain_generic_chip(domain, 0); 261 gc->private = priv; 262 gc->reg_base = base; 263 gc->domain = domain; 264 gc->resume = liointc_resume; 265 266 ct = gc->chip_types; 267 ct->regs.enable = LIOINTC_REG_INTC_ENABLE; 268 ct->regs.disable = LIOINTC_REG_INTC_DISABLE; 269 ct->chip.irq_unmask = irq_gc_unmask_enable_reg; 270 ct->chip.irq_mask = irq_gc_mask_disable_reg; 271 ct->chip.irq_mask_ack = irq_gc_mask_disable_reg; 272 ct->chip.irq_set_type = liointc_set_type; 273 274 gc->mask_cache = 0; 275 priv->gc = gc; 276 277 for (i = 0; i < LIOINTC_NUM_PARENT; i++) { 278 if (parent_irq[i] <= 0) 279 continue; 280 281 priv->handler[i].priv = priv; 282 irq_set_chained_handler_and_data(parent_irq[i], 283 liointc_chained_handle_irq, &priv->handler[i]); 284 } 285 286 liointc_handle = domain_handle; 287 return 0; 288 289 out_free_domain: 290 irq_domain_remove(domain); 291 out_iounmap: 292 iounmap(base); 293 out_free_priv: 294 kfree(priv); 295 296 return -EINVAL; 297 } 298 299 #ifdef CONFIG_OF 300 301 static int __init liointc_of_init(struct device_node *node, 302 struct device_node *parent) 303 { 304 bool have_parent = FALSE; 305 int sz, i, index, revision, err = 0; 306 struct resource res; 307 308 if (!of_device_is_compatible(node, "loongson,liointc-2.0")) { 309 index = 0; 310 revision = 1; 311 } else { 312 index = of_property_match_string(node, "reg-names", "main"); 313 revision = 2; 314 } 315 316 if (of_address_to_resource(node, index, &res)) 317 return -EINVAL; 318 319 for (i = 0; i < LIOINTC_NUM_PARENT; i++) { 320 parent_irq[i] = of_irq_get_byname(node, parent_names[i]); 321 if (parent_irq[i] > 0) 322 have_parent = TRUE; 323 } 324 if (!have_parent) 325 return -ENODEV; 326 327 sz = of_property_read_variable_u32_array(node, 328 "loongson,parent_int_map", 329 &parent_int_map[0], 330 LIOINTC_NUM_PARENT, 331 LIOINTC_NUM_PARENT); 332 if (sz < 4) { 333 pr_err("loongson-liointc: No parent_int_map\n"); 334 return -ENODEV; 335 } 336 337 err = liointc_init(res.start, resource_size(&res), 338 revision, of_node_to_fwnode(node), node); 339 if (err < 0) 340 return err; 341 342 return 0; 343 } 344 345 IRQCHIP_DECLARE(loongson_liointc_1_0, "loongson,liointc-1.0", liointc_of_init); 346 IRQCHIP_DECLARE(loongson_liointc_1_0a, "loongson,liointc-1.0a", liointc_of_init); 347 IRQCHIP_DECLARE(loongson_liointc_2_0, "loongson,liointc-2.0", liointc_of_init); 348 349 #endif 350 351 #ifdef CONFIG_ACPI 352 int __init liointc_acpi_init(struct irq_domain *parent, struct acpi_madt_lio_pic *acpi_liointc) 353 { 354 int ret; 355 struct fwnode_handle *domain_handle; 356 357 parent_int_map[0] = acpi_liointc->cascade_map[0]; 358 parent_int_map[1] = acpi_liointc->cascade_map[1]; 359 360 parent_irq[0] = irq_create_mapping(parent, acpi_liointc->cascade[0]); 361 parent_irq[1] = irq_create_mapping(parent, acpi_liointc->cascade[1]); 362 363 domain_handle = irq_domain_alloc_fwnode(&acpi_liointc->address); 364 if (!domain_handle) { 365 pr_err("Unable to allocate domain handle\n"); 366 return -ENOMEM; 367 } 368 ret = liointc_init(acpi_liointc->address, acpi_liointc->size, 369 1, domain_handle, NULL); 370 if (ret) 371 irq_domain_free_fwnode(domain_handle); 372 373 return ret; 374 } 375 #endif 376