1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * irqchip for the IXP4xx interrupt controller 4 * Copyright (C) 2019 Linus Walleij <linus.walleij@linaro.org> 5 * 6 * Based on arch/arm/mach-ixp4xx/common.c 7 * Copyright 2002 (C) Intel Corporation 8 * Copyright 2003-2004 (C) MontaVista, Software, Inc. 9 * Copyright (C) Deepak Saxena <dsaxena@plexity.net> 10 */ 11 #include <linux/bitops.h> 12 #include <linux/gpio/driver.h> 13 #include <linux/irq.h> 14 #include <linux/io.h> 15 #include <linux/irqchip.h> 16 #include <linux/irqchip/irq-ixp4xx.h> 17 #include <linux/irqdomain.h> 18 #include <linux/of.h> 19 #include <linux/of_address.h> 20 #include <linux/of_irq.h> 21 #include <linux/platform_device.h> 22 #include <linux/cpu.h> 23 24 #include <asm/exception.h> 25 #include <asm/mach/irq.h> 26 27 #define IXP4XX_ICPR 0x00 /* Interrupt Status */ 28 #define IXP4XX_ICMR 0x04 /* Interrupt Enable */ 29 #define IXP4XX_ICLR 0x08 /* Interrupt IRQ/FIQ Select */ 30 #define IXP4XX_ICIP 0x0C /* IRQ Status */ 31 #define IXP4XX_ICFP 0x10 /* FIQ Status */ 32 #define IXP4XX_ICHR 0x14 /* Interrupt Priority */ 33 #define IXP4XX_ICIH 0x18 /* IRQ Highest Pri Int */ 34 #define IXP4XX_ICFH 0x1C /* FIQ Highest Pri Int */ 35 36 /* IXP43x and IXP46x-only */ 37 #define IXP4XX_ICPR2 0x20 /* Interrupt Status 2 */ 38 #define IXP4XX_ICMR2 0x24 /* Interrupt Enable 2 */ 39 #define IXP4XX_ICLR2 0x28 /* Interrupt IRQ/FIQ Select 2 */ 40 #define IXP4XX_ICIP2 0x2C /* IRQ Status */ 41 #define IXP4XX_ICFP2 0x30 /* FIQ Status */ 42 #define IXP4XX_ICEEN 0x34 /* Error High Pri Enable */ 43 44 /** 45 * struct ixp4xx_irq - state container for the Faraday IRQ controller 46 * @irqbase: IRQ controller memory base in virtual memory 47 * @is_356: if this is an IXP43x, IXP45x or IX46x SoC (with 64 IRQs) 48 * @irqchip: irqchip for this instance 49 * @domain: IRQ domain for this instance 50 */ 51 struct ixp4xx_irq { 52 void __iomem *irqbase; 53 bool is_356; 54 struct irq_chip irqchip; 55 struct irq_domain *domain; 56 }; 57 58 /* Local static state container */ 59 static struct ixp4xx_irq ixirq; 60 61 /* GPIO Clocks */ 62 #define IXP4XX_GPIO_CLK_0 14 63 #define IXP4XX_GPIO_CLK_1 15 64 65 static int ixp4xx_set_irq_type(struct irq_data *d, unsigned int type) 66 { 67 /* All are level active high (asserted) here */ 68 if (type != IRQ_TYPE_LEVEL_HIGH) 69 return -EINVAL; 70 return 0; 71 } 72 73 static void ixp4xx_irq_mask(struct irq_data *d) 74 { 75 struct ixp4xx_irq *ixi = irq_data_get_irq_chip_data(d); 76 u32 val; 77 78 if (ixi->is_356 && d->hwirq >= 32) { 79 val = __raw_readl(ixi->irqbase + IXP4XX_ICMR2); 80 val &= ~BIT(d->hwirq - 32); 81 __raw_writel(val, ixi->irqbase + IXP4XX_ICMR2); 82 } else { 83 val = __raw_readl(ixi->irqbase + IXP4XX_ICMR); 84 val &= ~BIT(d->hwirq); 85 __raw_writel(val, ixi->irqbase + IXP4XX_ICMR); 86 } 87 } 88 89 /* 90 * Level triggered interrupts on GPIO lines can only be cleared when the 91 * interrupt condition disappears. 92 */ 93 static void ixp4xx_irq_unmask(struct irq_data *d) 94 { 95 struct ixp4xx_irq *ixi = irq_data_get_irq_chip_data(d); 96 u32 val; 97 98 if (ixi->is_356 && d->hwirq >= 32) { 99 val = __raw_readl(ixi->irqbase + IXP4XX_ICMR2); 100 val |= BIT(d->hwirq - 32); 101 __raw_writel(val, ixi->irqbase + IXP4XX_ICMR2); 102 } else { 103 val = __raw_readl(ixi->irqbase + IXP4XX_ICMR); 104 val |= BIT(d->hwirq); 105 __raw_writel(val, ixi->irqbase + IXP4XX_ICMR); 106 } 107 } 108 109 asmlinkage void __exception_irq_entry ixp4xx_handle_irq(struct pt_regs *regs) 110 { 111 struct ixp4xx_irq *ixi = &ixirq; 112 unsigned long status; 113 int i; 114 115 status = __raw_readl(ixi->irqbase + IXP4XX_ICIP); 116 for_each_set_bit(i, &status, 32) 117 handle_domain_irq(ixi->domain, i, regs); 118 119 /* 120 * IXP465/IXP435 has an upper IRQ status register 121 */ 122 if (ixi->is_356) { 123 status = __raw_readl(ixi->irqbase + IXP4XX_ICIP2); 124 for_each_set_bit(i, &status, 32) 125 handle_domain_irq(ixi->domain, i + 32, regs); 126 } 127 } 128 129 static int ixp4xx_irq_domain_translate(struct irq_domain *domain, 130 struct irq_fwspec *fwspec, 131 unsigned long *hwirq, 132 unsigned int *type) 133 { 134 /* We support standard DT translation */ 135 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) { 136 *hwirq = fwspec->param[0]; 137 *type = fwspec->param[1]; 138 return 0; 139 } 140 141 if (is_fwnode_irqchip(fwspec->fwnode)) { 142 if (fwspec->param_count != 2) 143 return -EINVAL; 144 *hwirq = fwspec->param[0]; 145 *type = fwspec->param[1]; 146 WARN_ON(*type == IRQ_TYPE_NONE); 147 return 0; 148 } 149 150 return -EINVAL; 151 } 152 153 static int ixp4xx_irq_domain_alloc(struct irq_domain *d, 154 unsigned int irq, unsigned int nr_irqs, 155 void *data) 156 { 157 struct ixp4xx_irq *ixi = d->host_data; 158 irq_hw_number_t hwirq; 159 unsigned int type = IRQ_TYPE_NONE; 160 struct irq_fwspec *fwspec = data; 161 int ret; 162 int i; 163 164 ret = ixp4xx_irq_domain_translate(d, fwspec, &hwirq, &type); 165 if (ret) 166 return ret; 167 168 for (i = 0; i < nr_irqs; i++) { 169 /* 170 * TODO: after converting IXP4xx to only device tree, set 171 * handle_bad_irq as default handler and assume all consumers 172 * call .set_type() as this is provided in the second cell in 173 * the device tree phandle. 174 */ 175 irq_domain_set_info(d, 176 irq + i, 177 hwirq + i, 178 &ixi->irqchip, 179 ixi, 180 handle_level_irq, 181 NULL, NULL); 182 irq_set_probe(irq + i); 183 } 184 185 return 0; 186 } 187 188 /* 189 * This needs to be a hierarchical irqdomain to work well with the 190 * GPIO irqchip (which is lower in the hierarchy) 191 */ 192 static const struct irq_domain_ops ixp4xx_irqdomain_ops = { 193 .translate = ixp4xx_irq_domain_translate, 194 .alloc = ixp4xx_irq_domain_alloc, 195 .free = irq_domain_free_irqs_common, 196 }; 197 198 /** 199 * ixp4xx_get_irq_domain() - retrieve the ixp4xx irq domain 200 * 201 * This function will go away when we transition to DT probing. 202 */ 203 struct irq_domain *ixp4xx_get_irq_domain(void) 204 { 205 struct ixp4xx_irq *ixi = &ixirq; 206 207 return ixi->domain; 208 } 209 EXPORT_SYMBOL_GPL(ixp4xx_get_irq_domain); 210 211 /* 212 * This is the Linux IRQ to hwirq mapping table. This goes away when 213 * we have DT support as all IRQ resources are defined in the device 214 * tree. It will register all the IRQs that are not used by the hierarchical 215 * GPIO IRQ chip. The "holes" inbetween these IRQs will be requested by 216 * the GPIO driver using . This is a step-gap solution. 217 */ 218 struct ixp4xx_irq_chunk { 219 int irq; 220 int hwirq; 221 int nr_irqs; 222 }; 223 224 static const struct ixp4xx_irq_chunk ixp4xx_irq_chunks[] = { 225 { 226 .irq = 16, 227 .hwirq = 0, 228 .nr_irqs = 6, 229 }, 230 { 231 .irq = 24, 232 .hwirq = 8, 233 .nr_irqs = 11, 234 }, 235 { 236 .irq = 46, 237 .hwirq = 30, 238 .nr_irqs = 2, 239 }, 240 /* Only on the 436 variants */ 241 { 242 .irq = 48, 243 .hwirq = 32, 244 .nr_irqs = 10, 245 }, 246 }; 247 248 /** 249 * ixp4x_irq_setup() - Common setup code for the IXP4xx interrupt controller 250 * @ixi: State container 251 * @irqbase: Virtual memory base for the interrupt controller 252 * @fwnode: Corresponding fwnode abstraction for this controller 253 * @is_356: if this is an IXP43x, IXP45x or IXP46x SoC variant 254 */ 255 static int ixp4xx_irq_setup(struct ixp4xx_irq *ixi, 256 void __iomem *irqbase, 257 struct fwnode_handle *fwnode, 258 bool is_356) 259 { 260 int nr_irqs; 261 262 ixi->irqbase = irqbase; 263 ixi->is_356 = is_356; 264 265 /* Route all sources to IRQ instead of FIQ */ 266 __raw_writel(0x0, ixi->irqbase + IXP4XX_ICLR); 267 268 /* Disable all interrupts */ 269 __raw_writel(0x0, ixi->irqbase + IXP4XX_ICMR); 270 271 if (is_356) { 272 /* Route upper 32 sources to IRQ instead of FIQ */ 273 __raw_writel(0x0, ixi->irqbase + IXP4XX_ICLR2); 274 275 /* Disable upper 32 interrupts */ 276 __raw_writel(0x0, ixi->irqbase + IXP4XX_ICMR2); 277 278 nr_irqs = 64; 279 } else { 280 nr_irqs = 32; 281 } 282 283 ixi->irqchip.name = "IXP4xx"; 284 ixi->irqchip.irq_mask = ixp4xx_irq_mask; 285 ixi->irqchip.irq_unmask = ixp4xx_irq_unmask; 286 ixi->irqchip.irq_set_type = ixp4xx_set_irq_type; 287 288 ixi->domain = irq_domain_create_linear(fwnode, nr_irqs, 289 &ixp4xx_irqdomain_ops, 290 ixi); 291 if (!ixi->domain) { 292 pr_crit("IXP4XX: can not add primary irqdomain\n"); 293 return -ENODEV; 294 } 295 296 set_handle_irq(ixp4xx_handle_irq); 297 298 return 0; 299 } 300 301 /** 302 * ixp4xx_irq_init() - Function to initialize the irqchip from boardfiles 303 * @irqbase: physical base for the irq controller 304 * @is_356: if this is an IXP43x, IXP45x or IXP46x SoC variant 305 */ 306 void __init ixp4xx_irq_init(resource_size_t irqbase, 307 bool is_356) 308 { 309 struct ixp4xx_irq *ixi = &ixirq; 310 void __iomem *base; 311 struct fwnode_handle *fwnode; 312 struct irq_fwspec fwspec; 313 int nr_chunks; 314 int ret; 315 int i; 316 317 base = ioremap(irqbase, 0x100); 318 if (!base) { 319 pr_crit("IXP4XX: could not ioremap interrupt controller\n"); 320 return; 321 } 322 fwnode = irq_domain_alloc_fwnode(base); 323 if (!fwnode) { 324 pr_crit("IXP4XX: no domain handle\n"); 325 return; 326 } 327 ret = ixp4xx_irq_setup(ixi, base, fwnode, is_356); 328 if (ret) { 329 pr_crit("IXP4XX: failed to set up irqchip\n"); 330 irq_domain_free_fwnode(fwnode); 331 } 332 333 nr_chunks = ARRAY_SIZE(ixp4xx_irq_chunks); 334 if (!is_356) 335 nr_chunks--; 336 337 /* 338 * After adding OF support, this is no longer needed: irqs 339 * will be allocated for the respective fwnodes. 340 */ 341 for (i = 0; i < nr_chunks; i++) { 342 const struct ixp4xx_irq_chunk *chunk = &ixp4xx_irq_chunks[i]; 343 344 pr_info("Allocate Linux IRQs %d..%d HW IRQs %d..%d\n", 345 chunk->irq, chunk->irq + chunk->nr_irqs - 1, 346 chunk->hwirq, chunk->hwirq + chunk->nr_irqs - 1); 347 fwspec.fwnode = fwnode; 348 fwspec.param[0] = chunk->hwirq; 349 fwspec.param[1] = IRQ_TYPE_LEVEL_HIGH; 350 fwspec.param_count = 2; 351 ret = __irq_domain_alloc_irqs(ixi->domain, 352 chunk->irq, 353 chunk->nr_irqs, 354 NUMA_NO_NODE, 355 &fwspec, 356 false, 357 NULL); 358 if (ret < 0) { 359 pr_crit("IXP4XX: can not allocate irqs in hierarchy %d\n", 360 ret); 361 return; 362 } 363 } 364 } 365 EXPORT_SYMBOL_GPL(ixp4xx_irq_init); 366 367 #ifdef CONFIG_OF 368 int __init ixp4xx_of_init_irq(struct device_node *np, 369 struct device_node *parent) 370 { 371 struct ixp4xx_irq *ixi = &ixirq; 372 void __iomem *base; 373 struct fwnode_handle *fwnode; 374 bool is_356; 375 int ret; 376 377 base = of_iomap(np, 0); 378 if (!base) { 379 pr_crit("IXP4XX: could not ioremap interrupt controller\n"); 380 return -ENODEV; 381 } 382 fwnode = of_node_to_fwnode(np); 383 384 /* These chip variants have 64 interrupts */ 385 is_356 = of_device_is_compatible(np, "intel,ixp43x-interrupt") || 386 of_device_is_compatible(np, "intel,ixp45x-interrupt") || 387 of_device_is_compatible(np, "intel,ixp46x-interrupt"); 388 389 ret = ixp4xx_irq_setup(ixi, base, fwnode, is_356); 390 if (ret) 391 pr_crit("IXP4XX: failed to set up irqchip\n"); 392 393 return ret; 394 } 395 IRQCHIP_DECLARE(ixp42x, "intel,ixp42x-interrupt", 396 ixp4xx_of_init_irq); 397 IRQCHIP_DECLARE(ixp43x, "intel,ixp43x-interrupt", 398 ixp4xx_of_init_irq); 399 IRQCHIP_DECLARE(ixp45x, "intel,ixp45x-interrupt", 400 ixp4xx_of_init_irq); 401 IRQCHIP_DECLARE(ixp46x, "intel,ixp46x-interrupt", 402 ixp4xx_of_init_irq); 403 #endif 404