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 #include <loongson.h> 20 21 #define LIOINTC_CHIP_IRQ 32 22 #define LIOINTC_NUM_PARENT 4 23 #define LIOINTC_NUM_CORES 4 24 25 #define LIOINTC_INTC_CHIP_START 0x20 26 27 #define LIOINTC_REG_INTC_STATUS (LIOINTC_INTC_CHIP_START + 0x20) 28 #define LIOINTC_REG_INTC_EN_STATUS (LIOINTC_INTC_CHIP_START + 0x04) 29 #define LIOINTC_REG_INTC_ENABLE (LIOINTC_INTC_CHIP_START + 0x08) 30 #define LIOINTC_REG_INTC_DISABLE (LIOINTC_INTC_CHIP_START + 0x0c) 31 #define LIOINTC_REG_INTC_POL (LIOINTC_INTC_CHIP_START + 0x10) 32 #define LIOINTC_REG_INTC_EDGE (LIOINTC_INTC_CHIP_START + 0x14) 33 34 #define LIOINTC_SHIFT_INTx 4 35 36 #define LIOINTC_ERRATA_IRQ 10 37 38 struct liointc_handler_data { 39 struct liointc_priv *priv; 40 u32 parent_int_map; 41 }; 42 43 struct liointc_priv { 44 struct irq_chip_generic *gc; 45 struct liointc_handler_data handler[LIOINTC_NUM_PARENT]; 46 void __iomem *core_isr[LIOINTC_NUM_CORES]; 47 u8 map_cache[LIOINTC_CHIP_IRQ]; 48 bool has_lpc_irq_errata; 49 }; 50 51 static void liointc_chained_handle_irq(struct irq_desc *desc) 52 { 53 struct liointc_handler_data *handler = irq_desc_get_handler_data(desc); 54 struct irq_chip *chip = irq_desc_get_chip(desc); 55 struct irq_chip_generic *gc = handler->priv->gc; 56 int core = get_ebase_cpunum() % LIOINTC_NUM_CORES; 57 u32 pending; 58 59 chained_irq_enter(chip, desc); 60 61 pending = readl(handler->priv->core_isr[core]); 62 63 if (!pending) { 64 /* Always blame LPC IRQ if we have that bug */ 65 if (handler->priv->has_lpc_irq_errata && 66 (handler->parent_int_map & gc->mask_cache & 67 BIT(LIOINTC_ERRATA_IRQ))) 68 pending = BIT(LIOINTC_ERRATA_IRQ); 69 else 70 spurious_interrupt(); 71 } 72 73 while (pending) { 74 int bit = __ffs(pending); 75 76 generic_handle_irq(irq_find_mapping(gc->domain, bit)); 77 pending &= ~BIT(bit); 78 } 79 80 chained_irq_exit(chip, desc); 81 } 82 83 static void liointc_set_bit(struct irq_chip_generic *gc, 84 unsigned int offset, 85 u32 mask, bool set) 86 { 87 if (set) 88 writel(readl(gc->reg_base + offset) | mask, 89 gc->reg_base + offset); 90 else 91 writel(readl(gc->reg_base + offset) & ~mask, 92 gc->reg_base + offset); 93 } 94 95 static int liointc_set_type(struct irq_data *data, unsigned int type) 96 { 97 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data); 98 u32 mask = data->mask; 99 unsigned long flags; 100 101 irq_gc_lock_irqsave(gc, flags); 102 switch (type) { 103 case IRQ_TYPE_LEVEL_HIGH: 104 liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, false); 105 liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, true); 106 break; 107 case IRQ_TYPE_LEVEL_LOW: 108 liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, false); 109 liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, false); 110 break; 111 case IRQ_TYPE_EDGE_RISING: 112 liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, true); 113 liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, true); 114 break; 115 case IRQ_TYPE_EDGE_FALLING: 116 liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, true); 117 liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, false); 118 break; 119 default: 120 irq_gc_unlock_irqrestore(gc, flags); 121 return -EINVAL; 122 } 123 irq_gc_unlock_irqrestore(gc, flags); 124 125 irqd_set_trigger_type(data, type); 126 return 0; 127 } 128 129 static void liointc_resume(struct irq_chip_generic *gc) 130 { 131 struct liointc_priv *priv = gc->private; 132 unsigned long flags; 133 int i; 134 135 irq_gc_lock_irqsave(gc, flags); 136 /* Disable all at first */ 137 writel(0xffffffff, gc->reg_base + LIOINTC_REG_INTC_DISABLE); 138 /* Restore map cache */ 139 for (i = 0; i < LIOINTC_CHIP_IRQ; i++) 140 writeb(priv->map_cache[i], gc->reg_base + i); 141 /* Restore mask cache */ 142 writel(gc->mask_cache, gc->reg_base + LIOINTC_REG_INTC_ENABLE); 143 irq_gc_unlock_irqrestore(gc, flags); 144 } 145 146 static const char * const parent_names[] = {"int0", "int1", "int2", "int3"}; 147 static const char * const core_reg_names[] = {"isr0", "isr1", "isr2", "isr3"}; 148 149 static void __iomem *liointc_get_reg_byname(struct device_node *node, 150 const char *name) 151 { 152 int index = of_property_match_string(node, "reg-names", name); 153 154 if (index < 0) 155 return NULL; 156 157 return of_iomap(node, index); 158 } 159 160 static int __init liointc_of_init(struct device_node *node, 161 struct device_node *parent) 162 { 163 struct irq_chip_generic *gc; 164 struct irq_domain *domain; 165 struct irq_chip_type *ct; 166 struct liointc_priv *priv; 167 void __iomem *base; 168 u32 of_parent_int_map[LIOINTC_NUM_PARENT]; 169 int parent_irq[LIOINTC_NUM_PARENT]; 170 bool have_parent = FALSE; 171 int sz, i, err = 0; 172 173 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 174 if (!priv) 175 return -ENOMEM; 176 177 if (of_device_is_compatible(node, "loongson,liointc-2.0")) { 178 base = liointc_get_reg_byname(node, "main"); 179 if (!base) { 180 err = -ENODEV; 181 goto out_free_priv; 182 } 183 184 for (i = 0; i < LIOINTC_NUM_CORES; i++) 185 priv->core_isr[i] = liointc_get_reg_byname(node, core_reg_names[i]); 186 if (!priv->core_isr[0]) { 187 err = -ENODEV; 188 goto out_iounmap_base; 189 } 190 } else { 191 base = of_iomap(node, 0); 192 if (!base) { 193 err = -ENODEV; 194 goto out_free_priv; 195 } 196 197 for (i = 0; i < LIOINTC_NUM_CORES; i++) 198 priv->core_isr[i] = base + LIOINTC_REG_INTC_STATUS; 199 } 200 201 for (i = 0; i < LIOINTC_NUM_PARENT; i++) { 202 parent_irq[i] = of_irq_get_byname(node, parent_names[i]); 203 if (parent_irq[i] > 0) 204 have_parent = TRUE; 205 } 206 if (!have_parent) { 207 err = -ENODEV; 208 goto out_iounmap_isr; 209 } 210 211 sz = of_property_read_variable_u32_array(node, 212 "loongson,parent_int_map", 213 &of_parent_int_map[0], 214 LIOINTC_NUM_PARENT, 215 LIOINTC_NUM_PARENT); 216 if (sz < 4) { 217 pr_err("loongson-liointc: No parent_int_map\n"); 218 err = -ENODEV; 219 goto out_iounmap_isr; 220 } 221 222 for (i = 0; i < LIOINTC_NUM_PARENT; i++) 223 priv->handler[i].parent_int_map = of_parent_int_map[i]; 224 225 /* Setup IRQ domain */ 226 domain = irq_domain_add_linear(node, 32, 227 &irq_generic_chip_ops, priv); 228 if (!domain) { 229 pr_err("loongson-liointc: cannot add IRQ domain\n"); 230 err = -EINVAL; 231 goto out_iounmap_isr; 232 } 233 234 err = irq_alloc_domain_generic_chips(domain, 32, 1, 235 node->full_name, handle_level_irq, 236 IRQ_NOPROBE, 0, 0); 237 if (err) { 238 pr_err("loongson-liointc: unable to register IRQ domain\n"); 239 goto out_free_domain; 240 } 241 242 243 /* Disable all IRQs */ 244 writel(0xffffffff, base + LIOINTC_REG_INTC_DISABLE); 245 /* Set to level triggered */ 246 writel(0x0, base + LIOINTC_REG_INTC_EDGE); 247 248 /* Generate parent INT part of map cache */ 249 for (i = 0; i < LIOINTC_NUM_PARENT; i++) { 250 u32 pending = priv->handler[i].parent_int_map; 251 252 while (pending) { 253 int bit = __ffs(pending); 254 255 priv->map_cache[bit] = BIT(i) << LIOINTC_SHIFT_INTx; 256 pending &= ~BIT(bit); 257 } 258 } 259 260 for (i = 0; i < LIOINTC_CHIP_IRQ; i++) { 261 /* Generate core part of map cache */ 262 priv->map_cache[i] |= BIT(loongson_sysconf.boot_cpu_id); 263 writeb(priv->map_cache[i], base + i); 264 } 265 266 gc = irq_get_domain_generic_chip(domain, 0); 267 gc->private = priv; 268 gc->reg_base = base; 269 gc->domain = domain; 270 gc->resume = liointc_resume; 271 272 ct = gc->chip_types; 273 ct->regs.enable = LIOINTC_REG_INTC_ENABLE; 274 ct->regs.disable = LIOINTC_REG_INTC_DISABLE; 275 ct->chip.irq_unmask = irq_gc_unmask_enable_reg; 276 ct->chip.irq_mask = irq_gc_mask_disable_reg; 277 ct->chip.irq_mask_ack = irq_gc_mask_disable_reg; 278 ct->chip.irq_set_type = liointc_set_type; 279 280 gc->mask_cache = 0; 281 priv->gc = gc; 282 283 for (i = 0; i < LIOINTC_NUM_PARENT; i++) { 284 if (parent_irq[i] <= 0) 285 continue; 286 287 priv->handler[i].priv = priv; 288 irq_set_chained_handler_and_data(parent_irq[i], 289 liointc_chained_handle_irq, &priv->handler[i]); 290 } 291 292 return 0; 293 294 out_free_domain: 295 irq_domain_remove(domain); 296 out_iounmap_isr: 297 for (i = 0; i < LIOINTC_NUM_CORES; i++) { 298 if (!priv->core_isr[i]) 299 continue; 300 iounmap(priv->core_isr[i]); 301 } 302 out_iounmap_base: 303 iounmap(base); 304 out_free_priv: 305 kfree(priv); 306 307 return err; 308 } 309 310 IRQCHIP_DECLARE(loongson_liointc_1_0, "loongson,liointc-1.0", liointc_of_init); 311 IRQCHIP_DECLARE(loongson_liointc_1_0a, "loongson,liointc-1.0a", liointc_of_init); 312 IRQCHIP_DECLARE(loongson_liointc_2_0, "loongson,liointc-2.0", liointc_of_init); 313