drivers/irqchip/irq-imgpdc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * IMG PowerDown Controller (PDC)
   4  *
   5  * Copyright 2010-2013 Imagination Technologies Ltd.
   6  *
   7  * Exposes the syswake and PDC peripheral wake interrupts to the system.
   8  *
   9  */
  10
  11 #include <linux/bitops.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/irqdomain.h>
  14 #include <linux/io.h>
  15 #include <linux/kernel.h>
  16 #include <linux/of.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/spinlock.h>
  19
  20 /* PDC interrupt register numbers */
  21
  22 #define PDC_IRQ_STATUS                  0x310
  23 #define PDC_IRQ_ENABLE                  0x314
  24 #define PDC_IRQ_CLEAR                   0x318
  25 #define PDC_IRQ_ROUTE                   0x31c
  26 #define PDC_SYS_WAKE_BASE               0x330
  27 #define PDC_SYS_WAKE_STRIDE             0x8
  28 #define PDC_SYS_WAKE_CONFIG_BASE        0x334
  29 #define PDC_SYS_WAKE_CONFIG_STRIDE      0x8
  30
  31 /* PDC interrupt register field masks */
  32
  33 #define PDC_IRQ_SYS3                    0x08
  34 #define PDC_IRQ_SYS2                    0x04
  35 #define PDC_IRQ_SYS1                    0x02
  36 #define PDC_IRQ_SYS0                    0x01
  37 #define PDC_IRQ_ROUTE_WU_EN_SYS3        0x08000000
  38 #define PDC_IRQ_ROUTE_WU_EN_SYS2        0x04000000
  39 #define PDC_IRQ_ROUTE_WU_EN_SYS1        0x02000000
  40 #define PDC_IRQ_ROUTE_WU_EN_SYS0        0x01000000
  41 #define PDC_IRQ_ROUTE_WU_EN_WD          0x00040000
  42 #define PDC_IRQ_ROUTE_WU_EN_IR          0x00020000
  43 #define PDC_IRQ_ROUTE_WU_EN_RTC         0x00010000
  44 #define PDC_IRQ_ROUTE_EXT_EN_SYS3       0x00000800
  45 #define PDC_IRQ_ROUTE_EXT_EN_SYS2       0x00000400
  46 #define PDC_IRQ_ROUTE_EXT_EN_SYS1       0x00000200
  47 #define PDC_IRQ_ROUTE_EXT_EN_SYS0       0x00000100
  48 #define PDC_IRQ_ROUTE_EXT_EN_WD         0x00000004
  49 #define PDC_IRQ_ROUTE_EXT_EN_IR         0x00000002
  50 #define PDC_IRQ_ROUTE_EXT_EN_RTC        0x00000001
  51 #define PDC_SYS_WAKE_RESET              0x00000010
  52 #define PDC_SYS_WAKE_INT_MODE           0x0000000e
  53 #define PDC_SYS_WAKE_INT_MODE_SHIFT     1
  54 #define PDC_SYS_WAKE_PIN_VAL            0x00000001
  55
  56 /* PDC interrupt constants */
  57
  58 #define PDC_SYS_WAKE_INT_LOW            0x0
  59 #define PDC_SYS_WAKE_INT_HIGH           0x1
  60 #define PDC_SYS_WAKE_INT_DOWN           0x2
  61 #define PDC_SYS_WAKE_INT_UP             0x3
  62 #define PDC_SYS_WAKE_INT_CHANGE         0x6
  63 #define PDC_SYS_WAKE_INT_NONE           0x4
  64
  65 /**
  66  * struct pdc_intc_priv - private pdc interrupt data.
  67  * @nr_perips:          Number of peripheral interrupt signals.
  68  * @nr_syswakes:        Number of syswake signals.
  69  * @perip_irqs:         List of peripheral IRQ numbers handled.
  70  * @syswake_irq:        Shared PDC syswake IRQ number.
  71  * @domain:             IRQ domain for PDC peripheral and syswake IRQs.
  72  * @pdc_base:           Base of PDC registers.
  73  * @irq_route:          Cached version of PDC_IRQ_ROUTE register.
  74  * @lock:               Lock to protect the PDC syswake registers and the cached
  75  *                      values of those registers in this struct.
  76  */
  77 struct pdc_intc_priv {
  78         unsigned int            nr_perips;
  79         unsigned int            nr_syswakes;
  80         unsigned int            *perip_irqs;
  81         unsigned int            syswake_irq;
  82         struct irq_domain       *domain;
  83         void __iomem            *pdc_base;
  84
  85         u32                     irq_route;
  86         raw_spinlock_t          lock;
  87 };
  88
  89 static void pdc_write(struct pdc_intc_priv *priv, unsigned int reg_offs,
  90                       unsigned int data)
  91 {
  92         iowrite32(data, priv->pdc_base + reg_offs);
  93 }
  94
  95 static unsigned int pdc_read(struct pdc_intc_priv *priv,
  96                              unsigned int reg_offs)
  97 {
  98         return ioread32(priv->pdc_base + reg_offs);
  99 }
 100
 101 /* Generic IRQ callbacks */
 102
 103 #define SYS0_HWIRQ      8
 104
 105 static unsigned int hwirq_is_syswake(irq_hw_number_t hw)
 106 {
 107         return hw >= SYS0_HWIRQ;
 108 }
 109
 110 static unsigned int hwirq_to_syswake(irq_hw_number_t hw)
 111 {
 112         return hw - SYS0_HWIRQ;
 113 }
 114
 115 static irq_hw_number_t syswake_to_hwirq(unsigned int syswake)
 116 {
 117         return SYS0_HWIRQ + syswake;
 118 }
 119
 120 static struct pdc_intc_priv *irqd_to_priv(struct irq_data *data)
 121 {
 122         return (struct pdc_intc_priv *)data->domain->host_data;
 123 }
 124
 125 /*
 126  * perip_irq_mask() and perip_irq_unmask() use IRQ_ROUTE which also contains
 127  * wake bits, therefore we cannot use the generic irqchip mask callbacks as they
 128  * cache the mask.
 129  */
 130
 131 static void perip_irq_mask(struct irq_data *data)
 132 {
 133         struct pdc_intc_priv *priv = irqd_to_priv(data);
 134
 135         raw_spin_lock(&priv->lock);
 136         priv->irq_route &= ~data->mask;
 137         pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
 138         raw_spin_unlock(&priv->lock);
 139 }
 140
 141 static void perip_irq_unmask(struct irq_data *data)
 142 {
 143         struct pdc_intc_priv *priv = irqd_to_priv(data);
 144
 145         raw_spin_lock(&priv->lock);
 146         priv->irq_route |= data->mask;
 147         pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
 148         raw_spin_unlock(&priv->lock);
 149 }
 150
 151 static int syswake_irq_set_type(struct irq_data *data, unsigned int flow_type)
 152 {
 153         struct pdc_intc_priv *priv = irqd_to_priv(data);
 154         unsigned int syswake = hwirq_to_syswake(data->hwirq);
 155         unsigned int irq_mode;
 156         unsigned int soc_sys_wake_regoff, soc_sys_wake;
 157
 158         /* translate to syswake IRQ mode */
 159         switch (flow_type) {
 160         case IRQ_TYPE_EDGE_BOTH:
 161                 irq_mode = PDC_SYS_WAKE_INT_CHANGE;
 162                 break;
 163         case IRQ_TYPE_EDGE_RISING:
 164                 irq_mode = PDC_SYS_WAKE_INT_UP;
 165                 break;
 166         case IRQ_TYPE_EDGE_FALLING:
 167                 irq_mode = PDC_SYS_WAKE_INT_DOWN;
 168                 break;
 169         case IRQ_TYPE_LEVEL_HIGH:
 170                 irq_mode = PDC_SYS_WAKE_INT_HIGH;
 171                 break;
 172         case IRQ_TYPE_LEVEL_LOW:
 173                 irq_mode = PDC_SYS_WAKE_INT_LOW;
 174                 break;
 175         default:
 176                 return -EINVAL;
 177         }
 178
 179         raw_spin_lock(&priv->lock);
 180
 181         /* set the IRQ mode */
 182         soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + syswake*PDC_SYS_WAKE_STRIDE;
 183         soc_sys_wake = pdc_read(priv, soc_sys_wake_regoff);
 184         soc_sys_wake &= ~PDC_SYS_WAKE_INT_MODE;
 185         soc_sys_wake |= irq_mode << PDC_SYS_WAKE_INT_MODE_SHIFT;
 186         pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
 187
 188         /* and update the handler */
 189         irq_setup_alt_chip(data, flow_type);
 190
 191         raw_spin_unlock(&priv->lock);
 192
 193         return 0;
 194 }
 195
 196 /* applies to both peripheral and syswake interrupts */
 197 static int pdc_irq_set_wake(struct irq_data *data, unsigned int on)
 198 {
 199         struct pdc_intc_priv *priv = irqd_to_priv(data);
 200         irq_hw_number_t hw = data->hwirq;
 201         unsigned int mask = (1 << 16) << hw;
 202         unsigned int dst_irq;
 203
 204         raw_spin_lock(&priv->lock);
 205         if (on)
 206                 priv->irq_route |= mask;
 207         else
 208                 priv->irq_route &= ~mask;
 209         pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
 210         raw_spin_unlock(&priv->lock);
 211
 212         /* control the destination IRQ wakeup too for standby mode */
 213         if (hwirq_is_syswake(hw))
 214                 dst_irq = priv->syswake_irq;
 215         else
 216                 dst_irq = priv->perip_irqs[hw];
 217         irq_set_irq_wake(dst_irq, on);
 218
 219         return 0;
 220 }
 221
 222 static void pdc_intc_perip_isr(struct irq_desc *desc)
 223 {
 224         unsigned int irq = irq_desc_get_irq(desc);
 225         struct pdc_intc_priv *priv;
 226         unsigned int i, irq_no;
 227
 228         priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
 229
 230         /* find the peripheral number */
 231         for (i = 0; i < priv->nr_perips; ++i)
 232                 if (irq == priv->perip_irqs[i])
 233                         goto found;
 234
 235         /* should never get here */
 236         return;
 237 found:
 238
 239         /* pass on the interrupt */
 240         irq_no = irq_linear_revmap(priv->domain, i);
 241         generic_handle_irq(irq_no);
 242 }
 243
 244 static void pdc_intc_syswake_isr(struct irq_desc *desc)
 245 {
 246         struct pdc_intc_priv *priv;
 247         unsigned int syswake, irq_no;
 248         unsigned int status;
 249
 250         priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
 251
 252         status = pdc_read(priv, PDC_IRQ_STATUS) &
 253                  pdc_read(priv, PDC_IRQ_ENABLE);
 254         status &= (1 << priv->nr_syswakes) - 1;
 255
 256         for (syswake = 0; status; status >>= 1, ++syswake) {
 257                 /* Has this sys_wake triggered? */
 258                 if (!(status & 1))
 259                         continue;
 260
 261                 irq_no = irq_linear_revmap(priv->domain,
 262                                            syswake_to_hwirq(syswake));
 263                 generic_handle_irq(irq_no);
 264         }
 265 }
 266
 267 static void pdc_intc_setup(struct pdc_intc_priv *priv)
 268 {
 269         int i;
 270         unsigned int soc_sys_wake_regoff;
 271         unsigned int soc_sys_wake;
 272
 273         /*
 274          * Mask all syswake interrupts before routing, or we could receive an
 275          * interrupt before we're ready to handle it.
 276          */
 277         pdc_write(priv, PDC_IRQ_ENABLE, 0);
 278
 279         /*
 280          * Enable routing of all syswakes
 281          * Disable all wake sources
 282          */
 283         priv->irq_route = ((PDC_IRQ_ROUTE_EXT_EN_SYS0 << priv->nr_syswakes) -
 284                                 PDC_IRQ_ROUTE_EXT_EN_SYS0);
 285         pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
 286
 287         /* Initialise syswake IRQ */
 288         for (i = 0; i < priv->nr_syswakes; ++i) {
 289                 /* set the IRQ mode to none */
 290                 soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + i*PDC_SYS_WAKE_STRIDE;
 291                 soc_sys_wake = PDC_SYS_WAKE_INT_NONE
 292                                 << PDC_SYS_WAKE_INT_MODE_SHIFT;
 293                 pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
 294         }
 295 }
 296
 297 static int pdc_intc_probe(struct platform_device *pdev)
 298 {
 299         struct pdc_intc_priv *priv;
 300         struct device_node *node = pdev->dev.of_node;
 301         struct resource *res_regs;
 302         struct irq_chip_generic *gc;
 303         unsigned int i;
 304         int irq, ret;
 305         u32 val;
 306
 307         if (!node)
 308                 return -ENOENT;
 309
 310         /* Get registers */
 311         res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 312         if (res_regs == NULL) {
 313                 dev_err(&pdev->dev, "cannot find registers resource\n");
 314                 return -ENOENT;
 315         }
 316
 317         /* Allocate driver data */
 318         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 319         if (!priv) {
 320                 dev_err(&pdev->dev, "cannot allocate device data\n");
 321                 return -ENOMEM;
 322         }
 323         raw_spin_lock_init(&priv->lock);
 324         platform_set_drvdata(pdev, priv);
 325
 326         /* Ioremap the registers */
 327         priv->pdc_base = devm_ioremap(&pdev->dev, res_regs->start,
 328                                       resource_size(res_regs));
 329         if (!priv->pdc_base)
 330                 return -EIO;
 331
 332         /* Get number of peripherals */
 333         ret = of_property_read_u32(node, "num-perips", &val);
 334         if (ret) {
 335                 dev_err(&pdev->dev, "No num-perips node property found\n");
 336                 return -EINVAL;
 337         }
 338         if (val > SYS0_HWIRQ) {
 339                 dev_err(&pdev->dev, "num-perips (%u) out of range\n", val);
 340                 return -EINVAL;
 341         }
 342         priv->nr_perips = val;
 343
 344         /* Get number of syswakes */
 345         ret = of_property_read_u32(node, "num-syswakes", &val);
 346         if (ret) {
 347                 dev_err(&pdev->dev, "No num-syswakes node property found\n");
 348                 return -EINVAL;
 349         }
 350         if (val > SYS0_HWIRQ) {
 351                 dev_err(&pdev->dev, "num-syswakes (%u) out of range\n", val);
 352                 return -EINVAL;
 353         }
 354         priv->nr_syswakes = val;
 355
 356         /* Get peripheral IRQ numbers */
 357         priv->perip_irqs = devm_kcalloc(&pdev->dev, 4, priv->nr_perips,
 358                                         GFP_KERNEL);
 359         if (!priv->perip_irqs) {
 360                 dev_err(&pdev->dev, "cannot allocate perip IRQ list\n");
 361                 return -ENOMEM;
 362         }
 363         for (i = 0; i < priv->nr_perips; ++i) {
 364                 irq = platform_get_irq(pdev, 1 + i);
 365                 if (irq < 0)
 366                         return irq;
 367                 priv->perip_irqs[i] = irq;
 368         }
 369         /* check if too many were provided */
 370         if (platform_get_irq(pdev, 1 + i) >= 0) {
 371                 dev_err(&pdev->dev, "surplus perip IRQs detected\n");
 372                 return -EINVAL;
 373         }
 374
 375         /* Get syswake IRQ number */
 376         irq = platform_get_irq(pdev, 0);
 377         if (irq < 0)
 378                 return irq;
 379         priv->syswake_irq = irq;
 380
 381         /* Set up an IRQ domain */
 382         priv->domain = irq_domain_add_linear(node, 16, &irq_generic_chip_ops,
 383                                              priv);
 384         if (unlikely(!priv->domain)) {
 385                 dev_err(&pdev->dev, "cannot add IRQ domain\n");
 386                 return -ENOMEM;
 387         }
 388
 389         /*
 390          * Set up 2 generic irq chips with 2 chip types.
 391          * The first one for peripheral irqs (only 1 chip type used)
 392          * The second one for syswake irqs (edge and level chip types)
 393          */
 394         ret = irq_alloc_domain_generic_chips(priv->domain, 8, 2, "pdc",
 395                                              handle_level_irq, 0, 0,
 396                                              IRQ_GC_INIT_NESTED_LOCK);
 397         if (ret)
 398                 goto err_generic;
 399
 400         /* peripheral interrupt chip */
 401
 402         gc = irq_get_domain_generic_chip(priv->domain, 0);
 403         gc->unused      = ~(BIT(priv->nr_perips) - 1);
 404         gc->reg_base    = priv->pdc_base;
 405         /*
 406          * IRQ_ROUTE contains wake bits, so we can't use the generic versions as
 407          * they cache the mask
 408          */
 409         gc->chip_types[0].regs.mask             = PDC_IRQ_ROUTE;
 410         gc->chip_types[0].chip.irq_mask         = perip_irq_mask;
 411         gc->chip_types[0].chip.irq_unmask       = perip_irq_unmask;
 412         gc->chip_types[0].chip.irq_set_wake     = pdc_irq_set_wake;
 413
 414         /* syswake interrupt chip */
 415
 416         gc = irq_get_domain_generic_chip(priv->domain, 8);
 417         gc->unused      = ~(BIT(priv->nr_syswakes) - 1);
 418         gc->reg_base    = priv->pdc_base;
 419
 420         /* edge interrupts */
 421         gc->chip_types[0].type                  = IRQ_TYPE_EDGE_BOTH;
 422         gc->chip_types[0].handler               = handle_edge_irq;
 423         gc->chip_types[0].regs.ack              = PDC_IRQ_CLEAR;
 424         gc->chip_types[0].regs.mask             = PDC_IRQ_ENABLE;
 425         gc->chip_types[0].chip.irq_ack          = irq_gc_ack_set_bit;
 426         gc->chip_types[0].chip.irq_mask         = irq_gc_mask_clr_bit;
 427         gc->chip_types[0].chip.irq_unmask       = irq_gc_mask_set_bit;
 428         gc->chip_types[0].chip.irq_set_type     = syswake_irq_set_type;
 429         gc->chip_types[0].chip.irq_set_wake     = pdc_irq_set_wake;
 430         /* for standby we pass on to the shared syswake IRQ */
 431         gc->chip_types[0].chip.flags            = IRQCHIP_MASK_ON_SUSPEND;
 432
 433         /* level interrupts */
 434         gc->chip_types[1].type                  = IRQ_TYPE_LEVEL_MASK;
 435         gc->chip_types[1].handler               = handle_level_irq;
 436         gc->chip_types[1].regs.ack              = PDC_IRQ_CLEAR;
 437         gc->chip_types[1].regs.mask             = PDC_IRQ_ENABLE;
 438         gc->chip_types[1].chip.irq_ack          = irq_gc_ack_set_bit;
 439         gc->chip_types[1].chip.irq_mask         = irq_gc_mask_clr_bit;
 440         gc->chip_types[1].chip.irq_unmask       = irq_gc_mask_set_bit;
 441         gc->chip_types[1].chip.irq_set_type     = syswake_irq_set_type;
 442         gc->chip_types[1].chip.irq_set_wake     = pdc_irq_set_wake;
 443         /* for standby we pass on to the shared syswake IRQ */
 444         gc->chip_types[1].chip.flags            = IRQCHIP_MASK_ON_SUSPEND;
 445
 446         /* Set up the hardware to enable interrupt routing */
 447         pdc_intc_setup(priv);
 448
 449         /* Setup chained handlers for the peripheral IRQs */
 450         for (i = 0; i < priv->nr_perips; ++i) {
 451                 irq = priv->perip_irqs[i];
 452                 irq_set_chained_handler_and_data(irq, pdc_intc_perip_isr,
 453                                                  priv);
 454         }
 455
 456         /* Setup chained handler for the syswake IRQ */
 457         irq_set_chained_handler_and_data(priv->syswake_irq,
 458                                          pdc_intc_syswake_isr, priv);
 459
 460         dev_info(&pdev->dev,
 461                  "PDC IRQ controller initialised (%u perip IRQs, %u syswake IRQs)\n",
 462                  priv->nr_perips,
 463                  priv->nr_syswakes);
 464
 465         return 0;
 466 err_generic:
 467         irq_domain_remove(priv->domain);
 468         return ret;
 469 }
 470
 471 static int pdc_intc_remove(struct platform_device *pdev)
 472 {
 473         struct pdc_intc_priv *priv = platform_get_drvdata(pdev);
 474
 475         irq_domain_remove(priv->domain);
 476         return 0;
 477 }
 478
 479 static const struct of_device_id pdc_intc_match[] = {
 480         { .compatible = "img,pdc-intc" },
 481         {}
 482 };
 483
 484 static struct platform_driver pdc_intc_driver = {
 485         .driver = {
 486                 .name           = "pdc-intc",
 487                 .of_match_table = pdc_intc_match,
 488         },
 489         .probe = pdc_intc_probe,
 490         .remove = pdc_intc_remove,
 491 };
 492
 493 static int __init pdc_intc_init(void)
 494 {
 495         return platform_driver_register(&pdc_intc_driver);
 496 }
 497 core_initcall(pdc_intc_init);