drivers/irqchip/irq-tegra.c

   1 /*
   2  * Driver code for Tegra's Legacy Interrupt Controller
   3  *
   4  * Author: Marc Zyngier <marc.zyngier@arm.com>
   5  *
   6  * Heavily based on the original arch/arm/mach-tegra/irq.c code:
   7  * Copyright (C) 2011 Google, Inc.
   8  *
   9  * Author:
  10  *      Colin Cross <ccross@android.com>
  11  *
  12  * Copyright (C) 2010,2013, NVIDIA Corporation
  13  *
  14  * This software is licensed under the terms of the GNU General Public
  15  * License version 2, as published by the Free Software Foundation, and
  16  * may be copied, distributed, and modified under those terms.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  */
  24
  25 #include <linux/io.h>
  26 #include <linux/irq.h>
  27 #include <linux/irqchip.h>
  28 #include <linux/irqdomain.h>
  29 #include <linux/of_address.h>
  30 #include <linux/slab.h>
  31 #include <linux/syscore_ops.h>
  32
  33 #include <dt-bindings/interrupt-controller/arm-gic.h>
  34
  35 #define ICTLR_CPU_IEP_VFIQ      0x08
  36 #define ICTLR_CPU_IEP_FIR       0x14
  37 #define ICTLR_CPU_IEP_FIR_SET   0x18
  38 #define ICTLR_CPU_IEP_FIR_CLR   0x1c
  39
  40 #define ICTLR_CPU_IER           0x20
  41 #define ICTLR_CPU_IER_SET       0x24
  42 #define ICTLR_CPU_IER_CLR       0x28
  43 #define ICTLR_CPU_IEP_CLASS     0x2C
  44
  45 #define ICTLR_COP_IER           0x30
  46 #define ICTLR_COP_IER_SET       0x34
  47 #define ICTLR_COP_IER_CLR       0x38
  48 #define ICTLR_COP_IEP_CLASS     0x3c
  49
  50 #define TEGRA_MAX_NUM_ICTLRS    6
  51
  52 static unsigned int num_ictlrs;
  53
  54 struct tegra_ictlr_soc {
  55         unsigned int num_ictlrs;
  56 };
  57
  58 static const struct tegra_ictlr_soc tegra20_ictlr_soc = {
  59         .num_ictlrs = 4,
  60 };
  61
  62 static const struct tegra_ictlr_soc tegra30_ictlr_soc = {
  63         .num_ictlrs = 5,
  64 };
  65
  66 static const struct tegra_ictlr_soc tegra210_ictlr_soc = {
  67         .num_ictlrs = 6,
  68 };
  69
  70 static const struct of_device_id ictlr_matches[] = {
  71         { .compatible = "nvidia,tegra210-ictlr", .data = &tegra210_ictlr_soc },
  72         { .compatible = "nvidia,tegra30-ictlr", .data = &tegra30_ictlr_soc },
  73         { .compatible = "nvidia,tegra20-ictlr", .data = &tegra20_ictlr_soc },
  74         { }
  75 };
  76
  77 struct tegra_ictlr_info {
  78         void __iomem *base[TEGRA_MAX_NUM_ICTLRS];
  79 #ifdef CONFIG_PM_SLEEP
  80         u32 cop_ier[TEGRA_MAX_NUM_ICTLRS];
  81         u32 cop_iep[TEGRA_MAX_NUM_ICTLRS];
  82         u32 cpu_ier[TEGRA_MAX_NUM_ICTLRS];
  83         u32 cpu_iep[TEGRA_MAX_NUM_ICTLRS];
  84
  85         u32 ictlr_wake_mask[TEGRA_MAX_NUM_ICTLRS];
  86 #endif
  87 };
  88
  89 static struct tegra_ictlr_info *lic;
  90
  91 static inline void tegra_ictlr_write_mask(struct irq_data *d, unsigned long reg)
  92 {
  93         void __iomem *base = d->chip_data;
  94         u32 mask;
  95
  96         mask = BIT(d->hwirq % 32);
  97         writel_relaxed(mask, base + reg);
  98 }
  99
 100 static void tegra_mask(struct irq_data *d)
 101 {
 102         tegra_ictlr_write_mask(d, ICTLR_CPU_IER_CLR);
 103         irq_chip_mask_parent(d);
 104 }
 105
 106 static void tegra_unmask(struct irq_data *d)
 107 {
 108         tegra_ictlr_write_mask(d, ICTLR_CPU_IER_SET);
 109         irq_chip_unmask_parent(d);
 110 }
 111
 112 static void tegra_eoi(struct irq_data *d)
 113 {
 114         tegra_ictlr_write_mask(d, ICTLR_CPU_IEP_FIR_CLR);
 115         irq_chip_eoi_parent(d);
 116 }
 117
 118 static int tegra_retrigger(struct irq_data *d)
 119 {
 120         tegra_ictlr_write_mask(d, ICTLR_CPU_IEP_FIR_SET);
 121         return irq_chip_retrigger_hierarchy(d);
 122 }
 123
 124 #ifdef CONFIG_PM_SLEEP
 125 static int tegra_set_wake(struct irq_data *d, unsigned int enable)
 126 {
 127         u32 irq = d->hwirq;
 128         u32 index, mask;
 129
 130         index = (irq / 32);
 131         mask = BIT(irq % 32);
 132         if (enable)
 133                 lic->ictlr_wake_mask[index] |= mask;
 134         else
 135                 lic->ictlr_wake_mask[index] &= ~mask;
 136
 137         /*
 138          * Do *not* call into the parent, as the GIC doesn't have any
 139          * wake-up facility...
 140          */
 141         return 0;
 142 }
 143
 144 static int tegra_ictlr_suspend(void)
 145 {
 146         unsigned long flags;
 147         unsigned int i;
 148
 149         local_irq_save(flags);
 150         for (i = 0; i < num_ictlrs; i++) {
 151                 void __iomem *ictlr = lic->base[i];
 152
 153                 /* Save interrupt state */
 154                 lic->cpu_ier[i] = readl_relaxed(ictlr + ICTLR_CPU_IER);
 155                 lic->cpu_iep[i] = readl_relaxed(ictlr + ICTLR_CPU_IEP_CLASS);
 156                 lic->cop_ier[i] = readl_relaxed(ictlr + ICTLR_COP_IER);
 157                 lic->cop_iep[i] = readl_relaxed(ictlr + ICTLR_COP_IEP_CLASS);
 158
 159                 /* Disable COP interrupts */
 160                 writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
 161
 162                 /* Disable CPU interrupts */
 163                 writel_relaxed(~0ul, ictlr + ICTLR_CPU_IER_CLR);
 164
 165                 /* Enable the wakeup sources of ictlr */
 166                 writel_relaxed(lic->ictlr_wake_mask[i], ictlr + ICTLR_CPU_IER_SET);
 167         }
 168         local_irq_restore(flags);
 169
 170         return 0;
 171 }
 172
 173 static void tegra_ictlr_resume(void)
 174 {
 175         unsigned long flags;
 176         unsigned int i;
 177
 178         local_irq_save(flags);
 179         for (i = 0; i < num_ictlrs; i++) {
 180                 void __iomem *ictlr = lic->base[i];
 181
 182                 writel_relaxed(lic->cpu_iep[i],
 183                                ictlr + ICTLR_CPU_IEP_CLASS);
 184                 writel_relaxed(~0ul, ictlr + ICTLR_CPU_IER_CLR);
 185                 writel_relaxed(lic->cpu_ier[i],
 186                                ictlr + ICTLR_CPU_IER_SET);
 187                 writel_relaxed(lic->cop_iep[i],
 188                                ictlr + ICTLR_COP_IEP_CLASS);
 189                 writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
 190                 writel_relaxed(lic->cop_ier[i],
 191                                ictlr + ICTLR_COP_IER_SET);
 192         }
 193         local_irq_restore(flags);
 194 }
 195
 196 static struct syscore_ops tegra_ictlr_syscore_ops = {
 197         .suspend        = tegra_ictlr_suspend,
 198         .resume         = tegra_ictlr_resume,
 199 };
 200
 201 static void tegra_ictlr_syscore_init(void)
 202 {
 203         register_syscore_ops(&tegra_ictlr_syscore_ops);
 204 }
 205 #else
 206 #define tegra_set_wake  NULL
 207 static inline void tegra_ictlr_syscore_init(void) {}
 208 #endif
 209
 210 static struct irq_chip tegra_ictlr_chip = {
 211         .name                   = "LIC",
 212         .irq_eoi                = tegra_eoi,
 213         .irq_mask               = tegra_mask,
 214         .irq_unmask             = tegra_unmask,
 215         .irq_retrigger          = tegra_retrigger,
 216         .irq_set_wake           = tegra_set_wake,
 217         .flags                  = IRQCHIP_MASK_ON_SUSPEND,
 218 #ifdef CONFIG_SMP
 219         .irq_set_affinity       = irq_chip_set_affinity_parent,
 220 #endif
 221 };
 222
 223 static int tegra_ictlr_domain_translate(struct irq_domain *d,
 224                                         struct irq_fwspec *fwspec,
 225                                         unsigned long *hwirq,
 226                                         unsigned int *type)
 227 {
 228         if (is_of_node(fwspec->fwnode)) {
 229                 if (fwspec->param_count != 3)
 230                         return -EINVAL;
 231
 232                 /* No PPI should point to this domain */
 233                 if (fwspec->param[0] != 0)
 234                         return -EINVAL;
 235
 236                 *hwirq = fwspec->param[1];
 237                 *type = fwspec->param[2];
 238                 return 0;
 239         }
 240
 241         return -EINVAL;
 242 }
 243
 244 static int tegra_ictlr_domain_alloc(struct irq_domain *domain,
 245                                     unsigned int virq,
 246                                     unsigned int nr_irqs, void *data)
 247 {
 248         struct irq_fwspec *fwspec = data;
 249         struct irq_fwspec parent_fwspec;
 250         struct tegra_ictlr_info *info = domain->host_data;
 251         irq_hw_number_t hwirq;
 252         unsigned int i;
 253
 254         if (fwspec->param_count != 3)
 255                 return -EINVAL; /* Not GIC compliant */
 256         if (fwspec->param[0] != GIC_SPI)
 257                 return -EINVAL; /* No PPI should point to this domain */
 258
 259         hwirq = fwspec->param[1];
 260         if (hwirq >= (num_ictlrs * 32))
 261                 return -EINVAL;
 262
 263         for (i = 0; i < nr_irqs; i++) {
 264                 int ictlr = (hwirq + i) / 32;
 265
 266                 irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
 267                                               &tegra_ictlr_chip,
 268                                               info->base[ictlr]);
 269         }
 270
 271         parent_fwspec = *fwspec;
 272         parent_fwspec.fwnode = domain->parent->fwnode;
 273         return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
 274                                             &parent_fwspec);
 275 }
 276
 277 static void tegra_ictlr_domain_free(struct irq_domain *domain,
 278                                     unsigned int virq,
 279                                     unsigned int nr_irqs)
 280 {
 281         unsigned int i;
 282
 283         for (i = 0; i < nr_irqs; i++) {
 284                 struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
 285                 irq_domain_reset_irq_data(d);
 286         }
 287 }
 288
 289 static const struct irq_domain_ops tegra_ictlr_domain_ops = {
 290         .translate      = tegra_ictlr_domain_translate,
 291         .alloc          = tegra_ictlr_domain_alloc,
 292         .free           = tegra_ictlr_domain_free,
 293 };
 294
 295 static int __init tegra_ictlr_init(struct device_node *node,
 296                                    struct device_node *parent)
 297 {
 298         struct irq_domain *parent_domain, *domain;
 299         const struct of_device_id *match;
 300         const struct tegra_ictlr_soc *soc;
 301         unsigned int i;
 302         int err;
 303
 304         if (!parent) {
 305                 pr_err("%s: no parent, giving up\n", node->full_name);
 306                 return -ENODEV;
 307         }
 308
 309         parent_domain = irq_find_host(parent);
 310         if (!parent_domain) {
 311                 pr_err("%s: unable to obtain parent domain\n", node->full_name);
 312                 return -ENXIO;
 313         }
 314
 315         match = of_match_node(ictlr_matches, node);
 316         if (!match)             /* Should never happen... */
 317                 return -ENODEV;
 318
 319         soc = match->data;
 320
 321         lic = kzalloc(sizeof(*lic), GFP_KERNEL);
 322         if (!lic)
 323                 return -ENOMEM;
 324
 325         for (i = 0; i < TEGRA_MAX_NUM_ICTLRS; i++) {
 326                 void __iomem *base;
 327
 328                 base = of_iomap(node, i);
 329                 if (!base)
 330                         break;
 331
 332                 lic->base[i] = base;
 333
 334                 /* Disable all interrupts */
 335                 writel_relaxed(~0UL, base + ICTLR_CPU_IER_CLR);
 336                 /* All interrupts target IRQ */
 337                 writel_relaxed(0, base + ICTLR_CPU_IEP_CLASS);
 338
 339                 num_ictlrs++;
 340         }
 341
 342         if (!num_ictlrs) {
 343                 pr_err("%s: no valid regions, giving up\n", node->full_name);
 344                 err = -ENOMEM;
 345                 goto out_free;
 346         }
 347
 348         WARN(num_ictlrs != soc->num_ictlrs,
 349              "%s: Found %u interrupt controllers in DT; expected %u.\n",
 350              node->full_name, num_ictlrs, soc->num_ictlrs);
 351
 352
 353         domain = irq_domain_add_hierarchy(parent_domain, 0, num_ictlrs * 32,
 354                                           node, &tegra_ictlr_domain_ops,
 355                                           lic);
 356         if (!domain) {
 357                 pr_err("%s: failed to allocated domain\n", node->full_name);
 358                 err = -ENOMEM;
 359                 goto out_unmap;
 360         }
 361
 362         tegra_ictlr_syscore_init();
 363
 364         pr_info("%s: %d interrupts forwarded to %s\n",
 365                 node->full_name, num_ictlrs * 32, parent->full_name);
 366
 367         return 0;
 368
 369 out_unmap:
 370         for (i = 0; i < num_ictlrs; i++)
 371                 iounmap(lic->base[i]);
 372 out_free:
 373         kfree(lic);
 374         return err;
 375 }
 376
 377 IRQCHIP_DECLARE(tegra20_ictlr, "nvidia,tegra20-ictlr", tegra_ictlr_init);
 378 IRQCHIP_DECLARE(tegra30_ictlr, "nvidia,tegra30-ictlr", tegra_ictlr_init);
 379 IRQCHIP_DECLARE(tegra210_ictlr, "nvidia,tegra210-ictlr", tegra_ictlr_init);