drivers/irqchip/irq-imx-intmux.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright 2017 NXP
   3
   4 /*                     INTMUX Block Diagram
   5  *
   6  *                               ________________
   7  * interrupt source #  0  +---->|                |
   8  *                        |     |                |
   9  * interrupt source #  1  +++-->|                |
  10  *            ...         | |   |   channel # 0  |--------->interrupt out # 0
  11  *            ...         | |   |                |
  12  *            ...         | |   |                |
  13  * interrupt source # X-1 +++-->|________________|
  14  *                        | | |
  15  *                        | | |
  16  *                        | | |  ________________
  17  *                        +---->|                |
  18  *                        | | | |                |
  19  *                        | +-->|                |
  20  *                        | | | |   channel # 1  |--------->interrupt out # 1
  21  *                        | | +>|                |
  22  *                        | | | |                |
  23  *                        | | | |________________|
  24  *                        | | |
  25  *                        | | |
  26  *                        | | |       ...
  27  *                        | | |       ...
  28  *                        | | |
  29  *                        | | |  ________________
  30  *                        +---->|                |
  31  *                          | | |                |
  32  *                          +-->|                |
  33  *                            | |   channel # N  |--------->interrupt out # N
  34  *                            +>|                |
  35  *                              |                |
  36  *                              |________________|
  37  *
  38  *
  39  * N: Interrupt Channel Instance Number (N=7)
  40  * X: Interrupt Source Number for each channel (X=32)
  41  *
  42  * The INTMUX interrupt multiplexer has 8 channels, each channel receives 32
  43  * interrupt sources and generates 1 interrupt output.
  44  *
  45  */
  46
  47 #include <linux/clk.h>
  48 #include <linux/interrupt.h>
  49 #include <linux/irq.h>
  50 #include <linux/irqchip/chained_irq.h>
  51 #include <linux/irqdomain.h>
  52 #include <linux/kernel.h>
  53 #include <linux/of_irq.h>
  54 #include <linux/of_platform.h>
  55 #include <linux/spinlock.h>
  56 #include <linux/pm_runtime.h>
  57
  58 #define CHANIER(n)      (0x10 + (0x40 * n))
  59 #define CHANIPR(n)      (0x20 + (0x40 * n))
  60
  61 #define CHAN_MAX_NUM            0x8
  62
  63 struct intmux_irqchip_data {
  64         struct irq_chip         chip;
  65         u32                     saved_reg;
  66         int                     chanidx;
  67         int                     irq;
  68         struct irq_domain       *domain;
  69 };
  70
  71 struct intmux_data {
  72         raw_spinlock_t                  lock;
  73         void __iomem                    *regs;
  74         struct clk                      *ipg_clk;
  75         int                             channum;
  76         struct intmux_irqchip_data      irqchip_data[];
  77 };
  78
  79 static void imx_intmux_irq_mask(struct irq_data *d)
  80 {
  81         struct intmux_irqchip_data *irqchip_data = d->chip_data;
  82         int idx = irqchip_data->chanidx;
  83         struct intmux_data *data = container_of(irqchip_data, struct intmux_data,
  84                                                 irqchip_data[idx]);
  85         unsigned long flags;
  86         void __iomem *reg;
  87         u32 val;
  88
  89         raw_spin_lock_irqsave(&data->lock, flags);
  90         reg = data->regs + CHANIER(idx);
  91         val = readl_relaxed(reg);
  92         /* disable the interrupt source of this channel */
  93         val &= ~BIT(d->hwirq);
  94         writel_relaxed(val, reg);
  95         raw_spin_unlock_irqrestore(&data->lock, flags);
  96 }
  97
  98 static void imx_intmux_irq_unmask(struct irq_data *d)
  99 {
 100         struct intmux_irqchip_data *irqchip_data = d->chip_data;
 101         int idx = irqchip_data->chanidx;
 102         struct intmux_data *data = container_of(irqchip_data, struct intmux_data,
 103                                                 irqchip_data[idx]);
 104         unsigned long flags;
 105         void __iomem *reg;
 106         u32 val;
 107
 108         raw_spin_lock_irqsave(&data->lock, flags);
 109         reg = data->regs + CHANIER(idx);
 110         val = readl_relaxed(reg);
 111         /* enable the interrupt source of this channel */
 112         val |= BIT(d->hwirq);
 113         writel_relaxed(val, reg);
 114         raw_spin_unlock_irqrestore(&data->lock, flags);
 115 }
 116
 117 static struct irq_chip imx_intmux_irq_chip = {
 118         .name           = "intmux",
 119         .irq_mask       = imx_intmux_irq_mask,
 120         .irq_unmask     = imx_intmux_irq_unmask,
 121 };
 122
 123 static int imx_intmux_irq_map(struct irq_domain *h, unsigned int irq,
 124                               irq_hw_number_t hwirq)
 125 {
 126         struct intmux_irqchip_data *data = h->host_data;
 127
 128         irq_set_chip_data(irq, data);
 129         irq_set_chip_and_handler(irq, &data->chip, handle_level_irq);
 130
 131         return 0;
 132 }
 133
 134 static int imx_intmux_irq_xlate(struct irq_domain *d, struct device_node *node,
 135                                 const u32 *intspec, unsigned int intsize,
 136                                 unsigned long *out_hwirq, unsigned int *out_type)
 137 {
 138         struct intmux_irqchip_data *irqchip_data = d->host_data;
 139         int idx = irqchip_data->chanidx;
 140         struct intmux_data *data = container_of(irqchip_data, struct intmux_data,
 141                                                 irqchip_data[idx]);
 142
 143         /*
 144          * two cells needed in interrupt specifier:
 145          * the 1st cell: hw interrupt number
 146          * the 2nd cell: channel index
 147          */
 148         if (WARN_ON(intsize != 2))
 149                 return -EINVAL;
 150
 151         if (WARN_ON(intspec[1] >= data->channum))
 152                 return -EINVAL;
 153
 154         *out_hwirq = intspec[0];
 155         *out_type = IRQ_TYPE_LEVEL_HIGH;
 156
 157         return 0;
 158 }
 159
 160 static int imx_intmux_irq_select(struct irq_domain *d, struct irq_fwspec *fwspec,
 161                                  enum irq_domain_bus_token bus_token)
 162 {
 163         struct intmux_irqchip_data *irqchip_data = d->host_data;
 164
 165         /* Not for us */
 166         if (fwspec->fwnode != d->fwnode)
 167                 return false;
 168
 169         return irqchip_data->chanidx == fwspec->param[1];
 170 }
 171
 172 static const struct irq_domain_ops imx_intmux_domain_ops = {
 173         .map            = imx_intmux_irq_map,
 174         .xlate          = imx_intmux_irq_xlate,
 175         .select         = imx_intmux_irq_select,
 176 };
 177
 178 static void imx_intmux_irq_handler(struct irq_desc *desc)
 179 {
 180         struct intmux_irqchip_data *irqchip_data = irq_desc_get_handler_data(desc);
 181         int idx = irqchip_data->chanidx;
 182         struct intmux_data *data = container_of(irqchip_data, struct intmux_data,
 183                                                 irqchip_data[idx]);
 184         unsigned long irqstat;
 185         int pos, virq;
 186
 187         chained_irq_enter(irq_desc_get_chip(desc), desc);
 188
 189         /* read the interrupt source pending status of this channel */
 190         irqstat = readl_relaxed(data->regs + CHANIPR(idx));
 191
 192         for_each_set_bit(pos, &irqstat, 32) {
 193                 virq = irq_find_mapping(irqchip_data->domain, pos);
 194                 if (virq)
 195                         generic_handle_irq(virq);
 196         }
 197
 198         chained_irq_exit(irq_desc_get_chip(desc), desc);
 199 }
 200
 201 static int imx_intmux_probe(struct platform_device *pdev)
 202 {
 203         struct device_node *np = pdev->dev.of_node;
 204         struct irq_domain *domain;
 205         struct intmux_data *data;
 206         int channum;
 207         int i, ret;
 208
 209         channum = platform_irq_count(pdev);
 210         if (channum == -EPROBE_DEFER) {
 211                 return -EPROBE_DEFER;
 212         } else if (channum > CHAN_MAX_NUM) {
 213                 dev_err(&pdev->dev, "supports up to %d multiplex channels\n",
 214                         CHAN_MAX_NUM);
 215                 return -EINVAL;
 216         }
 217
 218         data = devm_kzalloc(&pdev->dev, struct_size(data, irqchip_data, channum), GFP_KERNEL);
 219         if (!data)
 220                 return -ENOMEM;
 221
 222         data->regs = devm_platform_ioremap_resource(pdev, 0);
 223         if (IS_ERR(data->regs)) {
 224                 dev_err(&pdev->dev, "failed to initialize reg\n");
 225                 return PTR_ERR(data->regs);
 226         }
 227
 228         data->ipg_clk = devm_clk_get(&pdev->dev, "ipg");
 229         if (IS_ERR(data->ipg_clk))
 230                 return dev_err_probe(&pdev->dev, PTR_ERR(data->ipg_clk),
 231                                      "failed to get ipg clk\n");
 232
 233         data->channum = channum;
 234         raw_spin_lock_init(&data->lock);
 235
 236         pm_runtime_get_noresume(&pdev->dev);
 237         pm_runtime_set_active(&pdev->dev);
 238         pm_runtime_enable(&pdev->dev);
 239
 240         ret = clk_prepare_enable(data->ipg_clk);
 241         if (ret) {
 242                 dev_err(&pdev->dev, "failed to enable ipg clk: %d\n", ret);
 243                 return ret;
 244         }
 245
 246         for (i = 0; i < channum; i++) {
 247                 data->irqchip_data[i].chip = imx_intmux_irq_chip;
 248                 data->irqchip_data[i].chip.parent_device = &pdev->dev;
 249                 data->irqchip_data[i].chanidx = i;
 250
 251                 data->irqchip_data[i].irq = irq_of_parse_and_map(np, i);
 252                 if (data->irqchip_data[i].irq <= 0) {
 253                         ret = -EINVAL;
 254                         dev_err(&pdev->dev, "failed to get irq\n");
 255                         goto out;
 256                 }
 257
 258                 domain = irq_domain_add_linear(np, 32, &imx_intmux_domain_ops,
 259                                                &data->irqchip_data[i]);
 260                 if (!domain) {
 261                         ret = -ENOMEM;
 262                         dev_err(&pdev->dev, "failed to create IRQ domain\n");
 263                         goto out;
 264                 }
 265                 data->irqchip_data[i].domain = domain;
 266
 267                 /* disable all interrupt sources of this channel firstly */
 268                 writel_relaxed(0, data->regs + CHANIER(i));
 269
 270                 irq_set_chained_handler_and_data(data->irqchip_data[i].irq,
 271                                                  imx_intmux_irq_handler,
 272                                                  &data->irqchip_data[i]);
 273         }
 274
 275         platform_set_drvdata(pdev, data);
 276
 277         /*
 278          * Let pm_runtime_put() disable clock.
 279          * If CONFIG_PM is not enabled, the clock will stay powered.
 280          */
 281         pm_runtime_put(&pdev->dev);
 282
 283         return 0;
 284 out:
 285         clk_disable_unprepare(data->ipg_clk);
 286         return ret;
 287 }
 288
 289 static int imx_intmux_remove(struct platform_device *pdev)
 290 {
 291         struct intmux_data *data = platform_get_drvdata(pdev);
 292         int i;
 293
 294         for (i = 0; i < data->channum; i++) {
 295                 /* disable all interrupt sources of this channel */
 296                 writel_relaxed(0, data->regs + CHANIER(i));
 297
 298                 irq_set_chained_handler_and_data(data->irqchip_data[i].irq,
 299                                                  NULL, NULL);
 300
 301                 irq_domain_remove(data->irqchip_data[i].domain);
 302         }
 303
 304         pm_runtime_disable(&pdev->dev);
 305
 306         return 0;
 307 }
 308
 309 #ifdef CONFIG_PM
 310 static int imx_intmux_runtime_suspend(struct device *dev)
 311 {
 312         struct intmux_data *data = dev_get_drvdata(dev);
 313         struct intmux_irqchip_data *irqchip_data;
 314         int i;
 315
 316         for (i = 0; i < data->channum; i++) {
 317                 irqchip_data = &data->irqchip_data[i];
 318                 irqchip_data->saved_reg = readl_relaxed(data->regs + CHANIER(i));
 319         }
 320
 321         clk_disable_unprepare(data->ipg_clk);
 322
 323         return 0;
 324 }
 325
 326 static int imx_intmux_runtime_resume(struct device *dev)
 327 {
 328         struct intmux_data *data = dev_get_drvdata(dev);
 329         struct intmux_irqchip_data *irqchip_data;
 330         int ret, i;
 331
 332         ret = clk_prepare_enable(data->ipg_clk);
 333         if (ret) {
 334                 dev_err(dev, "failed to enable ipg clk: %d\n", ret);
 335                 return ret;
 336         }
 337
 338         for (i = 0; i < data->channum; i++) {
 339                 irqchip_data = &data->irqchip_data[i];
 340                 writel_relaxed(irqchip_data->saved_reg, data->regs + CHANIER(i));
 341         }
 342
 343         return 0;
 344 }
 345 #endif
 346
 347 static const struct dev_pm_ops imx_intmux_pm_ops = {
 348         SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 349                                       pm_runtime_force_resume)
 350         SET_RUNTIME_PM_OPS(imx_intmux_runtime_suspend,
 351                            imx_intmux_runtime_resume, NULL)
 352 };
 353
 354 static const struct of_device_id imx_intmux_id[] = {
 355         { .compatible = "fsl,imx-intmux", },
 356         { /* sentinel */ },
 357 };
 358
 359 static struct platform_driver imx_intmux_driver = {
 360         .driver = {
 361                 .name = "imx-intmux",
 362                 .of_match_table = imx_intmux_id,
 363                 .pm = &imx_intmux_pm_ops,
 364         },
 365         .probe = imx_intmux_probe,
 366         .remove = imx_intmux_remove,
 367 };
 368 builtin_platform_driver(imx_intmux_driver);