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_device.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                 dev_err(dev, "clk_enable failed: %d\n", ret);
  35                 return ret;
  36         }
  37
  38         /*
  39          * On the very first resume, the pointer to chip_pm->chip_data
  40          * will be NULL and this is intentional, because we do not
  41          * want to restore the GIC on the very first resume. So if
  42          * the pointer is not valid just return.
  43          */
  44         if (!gic)
  45                 return 0;
  46
  47         gic_dist_restore(gic);
  48         gic_cpu_restore(gic);
  49
  50         return 0;
  51 }
  52
  53 static int gic_runtime_suspend(struct device *dev)
  54 {
  55         struct gic_chip_pm *chip_pm = dev_get_drvdata(dev);
  56         struct gic_chip_data *gic = chip_pm->chip_data;
  57         const struct gic_clk_data *data = chip_pm->clk_data;
  58
  59         gic_dist_save(gic);
  60         gic_cpu_save(gic);
  61
  62         clk_bulk_disable_unprepare(data->num_clocks, chip_pm->clks);
  63
  64         return 0;
  65 }
  66
  67 static int gic_probe(struct platform_device *pdev)
  68 {
  69         struct device *dev = &pdev->dev;
  70         const struct gic_clk_data *data;
  71         struct gic_chip_pm *chip_pm;
  72         int ret, irq, i;
  73
  74         data = of_device_get_match_data(&pdev->dev);
  75         if (!data) {
  76                 dev_err(&pdev->dev, "no device match found\n");
  77                 return -ENODEV;
  78         }
  79
  80         chip_pm = devm_kzalloc(dev, sizeof(*chip_pm), GFP_KERNEL);
  81         if (!chip_pm)
  82                 return -ENOMEM;
  83
  84         irq = irq_of_parse_and_map(dev->of_node, 0);
  85         if (!irq) {
  86                 dev_err(dev, "no parent interrupt found!\n");
  87                 return -EINVAL;
  88         }
  89
  90         chip_pm->clks = devm_kcalloc(dev, data->num_clocks,
  91                                      sizeof(*chip_pm->clks), GFP_KERNEL);
  92         if (!chip_pm->clks)
  93                 return -ENOMEM;
  94
  95         for (i = 0; i < data->num_clocks; i++)
  96                 chip_pm->clks[i].id = data->clocks[i];
  97
  98         ret = devm_clk_bulk_get(dev, data->num_clocks, chip_pm->clks);
  99         if (ret)
 100                 goto irq_dispose;
 101
 102         chip_pm->clk_data = data;
 103         dev_set_drvdata(dev, chip_pm);
 104
 105         pm_runtime_enable(dev);
 106
 107         ret = pm_runtime_get_sync(dev);
 108         if (ret < 0)
 109                 goto rpm_disable;
 110
 111         ret = gic_of_init_child(dev, &chip_pm->chip_data, irq);
 112         if (ret)
 113                 goto rpm_put;
 114
 115         pm_runtime_put(dev);
 116
 117         dev_info(dev, "GIC IRQ controller registered\n");
 118
 119         return 0;
 120
 121 rpm_put:
 122         pm_runtime_put_sync(dev);
 123 rpm_disable:
 124         pm_runtime_disable(dev);
 125 irq_dispose:
 126         irq_dispose_mapping(irq);
 127
 128         return ret;
 129 }
 130
 131 static const struct dev_pm_ops gic_pm_ops = {
 132         SET_RUNTIME_PM_OPS(gic_runtime_suspend,
 133                            gic_runtime_resume, NULL)
 134         SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 135                                      pm_runtime_force_resume)
 136 };
 137
 138 static const char * const gic400_clocks[] = {
 139         "clk",
 140 };
 141
 142 static const struct gic_clk_data gic400_data = {
 143         .num_clocks = ARRAY_SIZE(gic400_clocks),
 144         .clocks = gic400_clocks,
 145 };
 146
 147 static const struct of_device_id gic_match[] = {
 148         { .compatible = "nvidia,tegra210-agic", .data = &gic400_data },
 149         {},
 150 };
 151 MODULE_DEVICE_TABLE(of, gic_match);
 152
 153 static struct platform_driver gic_driver = {
 154         .probe          = gic_probe,
 155         .driver         = {
 156                 .name   = "gic",
 157                 .of_match_table = gic_match,
 158                 .pm     = &gic_pm_ops,
 159         }
 160 };
 161
 162 builtin_platform_driver(gic_driver);