drivers/irqchip/irq-gic-pm.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2016 NVIDIA CORPORATION, All Rights Reserved.
   4  */
   5 #include <linux/module.h>
   6 #include <linux/clk.h>
   7 #include <linux/of.h>
   8 #include <linux/of_irq.h>
   9 #include <linux/irqchip/arm-gic.h>
  10 #include <linux/platform_device.h>
  11 #include <linux/pm_runtime.h>
  12 #include <linux/slab.h>
  13
  14 struct gic_clk_data {
  15         unsigned int num_clocks;
  16         const char *const *clocks;
  17 };
  18
  19 struct gic_chip_pm {
  20         struct gic_chip_data *chip_data;
  21         const struct gic_clk_data *clk_data;
  22         struct clk_bulk_data *clks;
  23 };
  24
  25 static int gic_runtime_resume(struct device *dev)
  26 {
  27         struct gic_chip_pm *chip_pm = dev_get_drvdata(dev);
  28         struct gic_chip_data *gic = chip_pm->chip_data;
  29         const struct gic_clk_data *data = chip_pm->clk_data;
  30         int ret;
  31
  32         ret = clk_bulk_prepare_enable(data->num_clocks, chip_pm->clks);
  33         if (ret)
  34                 return ret;
  35
  36         /*
  37          * On the very first resume, the pointer to chip_pm->chip_data
  38          * will be NULL and this is intentional, because we do not
  39          * want to restore the GIC on the very first resume. So if
  40          * the pointer is not valid just return.
  41          */
  42         if (!gic)
  43                 return 0;
  44
  45         gic_dist_restore(gic);
  46         gic_cpu_restore(gic);
  47
  48         return 0;
  49 }
  50
  51 static int gic_runtime_suspend(struct device *dev)
  52 {
  53         struct gic_chip_pm *chip_pm = dev_get_drvdata(dev);
  54         struct gic_chip_data *gic = chip_pm->chip_data;
  55         const struct gic_clk_data *data = chip_pm->clk_data;
  56
  57         gic_dist_save(gic);
  58         gic_cpu_save(gic);
  59
  60         clk_bulk_disable_unprepare(data->num_clocks, chip_pm->clks);
  61
  62         return 0;
  63 }
  64
  65 static int gic_probe(struct platform_device *pdev)
  66 {
  67         struct device *dev = &pdev->dev;
  68         const struct gic_clk_data *data;
  69         struct gic_chip_pm *chip_pm;
  70         int ret, irq, i;
  71
  72         data = of_device_get_match_data(&pdev->dev);
  73         if (!data) {
  74                 dev_err(&pdev->dev, "no device match found\n");
  75                 return -ENODEV;
  76         }
  77
  78         chip_pm = devm_kzalloc(dev, sizeof(*chip_pm), GFP_KERNEL);
  79         if (!chip_pm)
  80                 return -ENOMEM;
  81
  82         irq = irq_of_parse_and_map(dev->of_node, 0);
  83         if (!irq) {
  84                 dev_err(dev, "no parent interrupt found!\n");
  85                 return -EINVAL;
  86         }
  87
  88         chip_pm->clks = devm_kcalloc(dev, data->num_clocks,
  89                                      sizeof(*chip_pm->clks), GFP_KERNEL);
  90         if (!chip_pm->clks)
  91                 return -ENOMEM;
  92
  93         for (i = 0; i < data->num_clocks; i++)
  94                 chip_pm->clks[i].id = data->clocks[i];
  95
  96         ret = devm_clk_bulk_get(dev, data->num_clocks, chip_pm->clks);
  97         if (ret)
  98                 goto irq_dispose;
  99
 100         chip_pm->clk_data = data;
 101         dev_set_drvdata(dev, chip_pm);
 102
 103         pm_runtime_enable(dev);
 104
 105         ret = pm_runtime_resume_and_get(dev);
 106         if (ret < 0)
 107                 goto rpm_disable;
 108
 109         ret = gic_of_init_child(dev, &chip_pm->chip_data, irq);
 110         if (ret)
 111                 goto rpm_put;
 112
 113         pm_runtime_put(dev);
 114
 115         dev_info(dev, "GIC IRQ controller registered\n");
 116
 117         return 0;
 118
 119 rpm_put:
 120         pm_runtime_put_sync(dev);
 121 rpm_disable:
 122         pm_runtime_disable(dev);
 123 irq_dispose:
 124         irq_dispose_mapping(irq);
 125
 126         return ret;
 127 }
 128
 129 static const struct dev_pm_ops gic_pm_ops = {
 130         SET_RUNTIME_PM_OPS(gic_runtime_suspend,
 131                            gic_runtime_resume, NULL)
 132         SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 133                                      pm_runtime_force_resume)
 134 };
 135
 136 static const char * const gic400_clocks[] = {
 137         "clk",
 138 };
 139
 140 static const struct gic_clk_data gic400_data = {
 141         .num_clocks = ARRAY_SIZE(gic400_clocks),
 142         .clocks = gic400_clocks,
 143 };
 144
 145 static const struct of_device_id gic_match[] = {
 146         { .compatible = "nvidia,tegra210-agic", .data = &gic400_data },
 147         {},
 148 };
 149 MODULE_DEVICE_TABLE(of, gic_match);
 150
 151 static struct platform_driver gic_driver = {
 152         .probe          = gic_probe,
 153         .driver         = {
 154                 .name   = "gic",
 155                 .of_match_table = gic_match,
 156                 .pm     = &gic_pm_ops,
 157         }
 158 };
 159
 160 builtin_platform_driver(gic_driver);