drivers/irqchip/irq-hip04.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Hisilicon HiP04 INTC
   4  *
   5  * Copyright (C) 2002-2014 ARM Limited.
   6  * Copyright (c) 2013-2014 Hisilicon Ltd.
   7  * Copyright (c) 2013-2014 Linaro Ltd.
   8  *
   9  * Interrupt architecture for the HIP04 INTC:
  10  *
  11  * o There is one Interrupt Distributor, which receives interrupts
  12  *   from system devices and sends them to the Interrupt Controllers.
  13  *
  14  * o There is one CPU Interface per CPU, which sends interrupts sent
  15  *   by the Distributor, and interrupts generated locally, to the
  16  *   associated CPU. The base address of the CPU interface is usually
  17  *   aliased so that the same address points to different chips depending
  18  *   on the CPU it is accessed from.
  19  *
  20  * Note that IRQs 0-31 are special - they are local to each CPU.
  21  * As such, the enable set/clear, pending set/clear and active bit
  22  * registers are banked per-cpu for these sources.
  23  */
  24
  25 #include <linux/init.h>
  26 #include <linux/kernel.h>
  27 #include <linux/err.h>
  28 #include <linux/module.h>
  29 #include <linux/list.h>
  30 #include <linux/smp.h>
  31 #include <linux/cpu.h>
  32 #include <linux/cpu_pm.h>
  33 #include <linux/cpumask.h>
  34 #include <linux/io.h>
  35 #include <linux/of.h>
  36 #include <linux/of_address.h>
  37 #include <linux/of_irq.h>
  38 #include <linux/irqdomain.h>
  39 #include <linux/interrupt.h>
  40 #include <linux/slab.h>
  41 #include <linux/irqchip.h>
  42 #include <linux/irqchip/arm-gic.h>
  43
  44 #include <asm/irq.h>
  45 #include <asm/exception.h>
  46 #include <asm/smp_plat.h>
  47
  48 #include "irq-gic-common.h"
  49
  50 #define HIP04_MAX_IRQS          510
  51
  52 struct hip04_irq_data {
  53         void __iomem *dist_base;
  54         void __iomem *cpu_base;
  55         struct irq_domain *domain;
  56         unsigned int nr_irqs;
  57 };
  58
  59 static DEFINE_RAW_SPINLOCK(irq_controller_lock);
  60
  61 /*
  62  * The GIC mapping of CPU interfaces does not necessarily match
  63  * the logical CPU numbering.  Let's use a mapping as returned
  64  * by the GIC itself.
  65  */
  66 #define NR_HIP04_CPU_IF 16
  67 static u16 hip04_cpu_map[NR_HIP04_CPU_IF] __read_mostly;
  68
  69 static struct hip04_irq_data hip04_data __read_mostly;
  70
  71 static inline void __iomem *hip04_dist_base(struct irq_data *d)
  72 {
  73         struct hip04_irq_data *hip04_data = irq_data_get_irq_chip_data(d);
  74         return hip04_data->dist_base;
  75 }
  76
  77 static inline void __iomem *hip04_cpu_base(struct irq_data *d)
  78 {
  79         struct hip04_irq_data *hip04_data = irq_data_get_irq_chip_data(d);
  80         return hip04_data->cpu_base;
  81 }
  82
  83 static inline unsigned int hip04_irq(struct irq_data *d)
  84 {
  85         return d->hwirq;
  86 }
  87
  88 /*
  89  * Routines to acknowledge, disable and enable interrupts
  90  */
  91 static void hip04_mask_irq(struct irq_data *d)
  92 {
  93         u32 mask = 1 << (hip04_irq(d) % 32);
  94
  95         raw_spin_lock(&irq_controller_lock);
  96         writel_relaxed(mask, hip04_dist_base(d) + GIC_DIST_ENABLE_CLEAR +
  97                        (hip04_irq(d) / 32) * 4);
  98         raw_spin_unlock(&irq_controller_lock);
  99 }
 100
 101 static void hip04_unmask_irq(struct irq_data *d)
 102 {
 103         u32 mask = 1 << (hip04_irq(d) % 32);
 104
 105         raw_spin_lock(&irq_controller_lock);
 106         writel_relaxed(mask, hip04_dist_base(d) + GIC_DIST_ENABLE_SET +
 107                        (hip04_irq(d) / 32) * 4);
 108         raw_spin_unlock(&irq_controller_lock);
 109 }
 110
 111 static void hip04_eoi_irq(struct irq_data *d)
 112 {
 113         writel_relaxed(hip04_irq(d), hip04_cpu_base(d) + GIC_CPU_EOI);
 114 }
 115
 116 static int hip04_irq_set_type(struct irq_data *d, unsigned int type)
 117 {
 118         void __iomem *base = hip04_dist_base(d);
 119         unsigned int irq = hip04_irq(d);
 120         int ret;
 121
 122         /* Interrupt configuration for SGIs can't be changed */
 123         if (irq < 16)
 124                 return -EINVAL;
 125
 126         /* SPIs have restrictions on the supported types */
 127         if (irq >= 32 && type != IRQ_TYPE_LEVEL_HIGH &&
 128                          type != IRQ_TYPE_EDGE_RISING)
 129                 return -EINVAL;
 130
 131         raw_spin_lock(&irq_controller_lock);
 132
 133         ret = gic_configure_irq(irq, type, base, NULL);
 134
 135         raw_spin_unlock(&irq_controller_lock);
 136
 137         return ret;
 138 }
 139
 140 #ifdef CONFIG_SMP
 141 static int hip04_irq_set_affinity(struct irq_data *d,
 142                                   const struct cpumask *mask_val,
 143                                   bool force)
 144 {
 145         void __iomem *reg;
 146         unsigned int cpu, shift = (hip04_irq(d) % 2) * 16;
 147         u32 val, mask, bit;
 148
 149         if (!force)
 150                 cpu = cpumask_any_and(mask_val, cpu_online_mask);
 151         else
 152                 cpu = cpumask_first(mask_val);
 153
 154         if (cpu >= NR_HIP04_CPU_IF || cpu >= nr_cpu_ids)
 155                 return -EINVAL;
 156
 157         raw_spin_lock(&irq_controller_lock);
 158         reg = hip04_dist_base(d) + GIC_DIST_TARGET + ((hip04_irq(d) * 2) & ~3);
 159         mask = 0xffff << shift;
 160         bit = hip04_cpu_map[cpu] << shift;
 161         val = readl_relaxed(reg) & ~mask;
 162         writel_relaxed(val | bit, reg);
 163         raw_spin_unlock(&irq_controller_lock);
 164
 165         irq_data_update_effective_affinity(d, cpumask_of(cpu));
 166
 167         return IRQ_SET_MASK_OK;
 168 }
 169 #endif
 170
 171 static void __exception_irq_entry hip04_handle_irq(struct pt_regs *regs)
 172 {
 173         u32 irqstat, irqnr;
 174         void __iomem *cpu_base = hip04_data.cpu_base;
 175
 176         do {
 177                 irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK);
 178                 irqnr = irqstat & GICC_IAR_INT_ID_MASK;
 179
 180                 if (likely(irqnr > 15 && irqnr <= HIP04_MAX_IRQS)) {
 181                         handle_domain_irq(hip04_data.domain, irqnr, regs);
 182                         continue;
 183                 }
 184                 if (irqnr < 16) {
 185                         writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
 186 #ifdef CONFIG_SMP
 187                         handle_IPI(irqnr, regs);
 188 #endif
 189                         continue;
 190                 }
 191                 break;
 192         } while (1);
 193 }
 194
 195 static struct irq_chip hip04_irq_chip = {
 196         .name                   = "HIP04 INTC",
 197         .irq_mask               = hip04_mask_irq,
 198         .irq_unmask             = hip04_unmask_irq,
 199         .irq_eoi                = hip04_eoi_irq,
 200         .irq_set_type           = hip04_irq_set_type,
 201 #ifdef CONFIG_SMP
 202         .irq_set_affinity       = hip04_irq_set_affinity,
 203 #endif
 204         .flags                  = IRQCHIP_SET_TYPE_MASKED |
 205                                   IRQCHIP_SKIP_SET_WAKE |
 206                                   IRQCHIP_MASK_ON_SUSPEND,
 207 };
 208
 209 static u16 hip04_get_cpumask(struct hip04_irq_data *intc)
 210 {
 211         void __iomem *base = intc->dist_base;
 212         u32 mask, i;
 213
 214         for (i = mask = 0; i < 32; i += 2) {
 215                 mask = readl_relaxed(base + GIC_DIST_TARGET + i * 2);
 216                 mask |= mask >> 16;
 217                 if (mask)
 218                         break;
 219         }
 220
 221         if (!mask)
 222                 pr_crit("GIC CPU mask not found - kernel will fail to boot.\n");
 223
 224         return mask;
 225 }
 226
 227 static void __init hip04_irq_dist_init(struct hip04_irq_data *intc)
 228 {
 229         unsigned int i;
 230         u32 cpumask;
 231         unsigned int nr_irqs = intc->nr_irqs;
 232         void __iomem *base = intc->dist_base;
 233
 234         writel_relaxed(0, base + GIC_DIST_CTRL);
 235
 236         /*
 237          * Set all global interrupts to this CPU only.
 238          */
 239         cpumask = hip04_get_cpumask(intc);
 240         cpumask |= cpumask << 16;
 241         for (i = 32; i < nr_irqs; i += 2)
 242                 writel_relaxed(cpumask, base + GIC_DIST_TARGET + ((i * 2) & ~3));
 243
 244         gic_dist_config(base, nr_irqs, NULL);
 245
 246         writel_relaxed(1, base + GIC_DIST_CTRL);
 247 }
 248
 249 static void hip04_irq_cpu_init(struct hip04_irq_data *intc)
 250 {
 251         void __iomem *dist_base = intc->dist_base;
 252         void __iomem *base = intc->cpu_base;
 253         unsigned int cpu_mask, cpu = smp_processor_id();
 254         int i;
 255
 256         /*
 257          * Get what the GIC says our CPU mask is.
 258          */
 259         BUG_ON(cpu >= NR_HIP04_CPU_IF);
 260         cpu_mask = hip04_get_cpumask(intc);
 261         hip04_cpu_map[cpu] = cpu_mask;
 262
 263         /*
 264          * Clear our mask from the other map entries in case they're
 265          * still undefined.
 266          */
 267         for (i = 0; i < NR_HIP04_CPU_IF; i++)
 268                 if (i != cpu)
 269                         hip04_cpu_map[i] &= ~cpu_mask;
 270
 271         gic_cpu_config(dist_base, NULL);
 272
 273         writel_relaxed(0xf0, base + GIC_CPU_PRIMASK);
 274         writel_relaxed(1, base + GIC_CPU_CTRL);
 275 }
 276
 277 #ifdef CONFIG_SMP
 278 static void hip04_raise_softirq(const struct cpumask *mask, unsigned int irq)
 279 {
 280         int cpu;
 281         unsigned long flags, map = 0;
 282
 283         raw_spin_lock_irqsave(&irq_controller_lock, flags);
 284
 285         /* Convert our logical CPU mask into a physical one. */
 286         for_each_cpu(cpu, mask)
 287                 map |= hip04_cpu_map[cpu];
 288
 289         /*
 290          * Ensure that stores to Normal memory are visible to the
 291          * other CPUs before they observe us issuing the IPI.
 292          */
 293         dmb(ishst);
 294
 295         /* this always happens on GIC0 */
 296         writel_relaxed(map << 8 | irq, hip04_data.dist_base + GIC_DIST_SOFTINT);
 297
 298         raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
 299 }
 300 #endif
 301
 302 static int hip04_irq_domain_map(struct irq_domain *d, unsigned int irq,
 303                                 irq_hw_number_t hw)
 304 {
 305         if (hw < 32) {
 306                 irq_set_percpu_devid(irq);
 307                 irq_set_chip_and_handler(irq, &hip04_irq_chip,
 308                                          handle_percpu_devid_irq);
 309                 irq_set_status_flags(irq, IRQ_NOAUTOEN);
 310         } else {
 311                 irq_set_chip_and_handler(irq, &hip04_irq_chip,
 312                                          handle_fasteoi_irq);
 313                 irq_set_probe(irq);
 314                 irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq)));
 315         }
 316         irq_set_chip_data(irq, d->host_data);
 317         return 0;
 318 }
 319
 320 static int hip04_irq_domain_xlate(struct irq_domain *d,
 321                                   struct device_node *controller,
 322                                   const u32 *intspec, unsigned int intsize,
 323                                   unsigned long *out_hwirq,
 324                                   unsigned int *out_type)
 325 {
 326         unsigned long ret = 0;
 327
 328         if (irq_domain_get_of_node(d) != controller)
 329                 return -EINVAL;
 330         if (intsize < 3)
 331                 return -EINVAL;
 332
 333         /* Get the interrupt number and add 16 to skip over SGIs */
 334         *out_hwirq = intspec[1] + 16;
 335
 336         /* For SPIs, we need to add 16 more to get the irq ID number */
 337         if (!intspec[0])
 338                 *out_hwirq += 16;
 339
 340         *out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
 341
 342         return ret;
 343 }
 344
 345 static int hip04_irq_starting_cpu(unsigned int cpu)
 346 {
 347         hip04_irq_cpu_init(&hip04_data);
 348         return 0;
 349 }
 350
 351 static const struct irq_domain_ops hip04_irq_domain_ops = {
 352         .map    = hip04_irq_domain_map,
 353         .xlate  = hip04_irq_domain_xlate,
 354 };
 355
 356 static int __init
 357 hip04_of_init(struct device_node *node, struct device_node *parent)
 358 {
 359         irq_hw_number_t hwirq_base = 16;
 360         int nr_irqs, irq_base, i;
 361
 362         if (WARN_ON(!node))
 363                 return -ENODEV;
 364
 365         hip04_data.dist_base = of_iomap(node, 0);
 366         WARN(!hip04_data.dist_base, "fail to map hip04 intc dist registers\n");
 367
 368         hip04_data.cpu_base = of_iomap(node, 1);
 369         WARN(!hip04_data.cpu_base, "unable to map hip04 intc cpu registers\n");
 370
 371         /*
 372          * Initialize the CPU interface map to all CPUs.
 373          * It will be refined as each CPU probes its ID.
 374          */
 375         for (i = 0; i < NR_HIP04_CPU_IF; i++)
 376                 hip04_cpu_map[i] = 0xffff;
 377
 378         /*
 379          * Find out how many interrupts are supported.
 380          * The HIP04 INTC only supports up to 510 interrupt sources.
 381          */
 382         nr_irqs = readl_relaxed(hip04_data.dist_base + GIC_DIST_CTR) & 0x1f;
 383         nr_irqs = (nr_irqs + 1) * 32;
 384         if (nr_irqs > HIP04_MAX_IRQS)
 385                 nr_irqs = HIP04_MAX_IRQS;
 386         hip04_data.nr_irqs = nr_irqs;
 387
 388         nr_irqs -= hwirq_base; /* calculate # of irqs to allocate */
 389
 390         irq_base = irq_alloc_descs(-1, hwirq_base, nr_irqs, numa_node_id());
 391         if (irq_base < 0) {
 392                 pr_err("failed to allocate IRQ numbers\n");
 393                 return -EINVAL;
 394         }
 395
 396         hip04_data.domain = irq_domain_add_legacy(node, nr_irqs, irq_base,
 397                                                   hwirq_base,
 398                                                   &hip04_irq_domain_ops,
 399                                                   &hip04_data);
 400
 401         if (WARN_ON(!hip04_data.domain))
 402                 return -EINVAL;
 403
 404 #ifdef CONFIG_SMP
 405         set_smp_cross_call(hip04_raise_softirq);
 406 #endif
 407         set_handle_irq(hip04_handle_irq);
 408
 409         hip04_irq_dist_init(&hip04_data);
 410         cpuhp_setup_state(CPUHP_AP_IRQ_HIP04_STARTING, "irqchip/hip04:starting",
 411                           hip04_irq_starting_cpu, NULL);
 412         return 0;
 413 }
 414 IRQCHIP_DECLARE(hip04_intc, "hisilicon,hip04-intc", hip04_of_init);