drivers/irqchip/irq-gic-pm.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Copyright (C) 2016 NVIDIA CORPORATION, All Rights Reserved.
0004  */
0005 #include <linux/module.h>
0006 #include <linux/clk.h>
0007 #include <linux/of_device.h>
0008 #include <linux/of_irq.h>
0009 #include <linux/irqchip/arm-gic.h>
0010 #include <linux/platform_device.h>
0011 #include <linux/pm_runtime.h>
0012 #include <linux/slab.h>
0013
0014 struct gic_clk_data {
0015     unsigned int num_clocks;
0016     const char *const *clocks;
0017 };
0018
0019 struct gic_chip_pm {
0020     struct gic_chip_data *chip_data;
0021     const struct gic_clk_data *clk_data;
0022     struct clk_bulk_data *clks;
0023 };
0024
0025 static int gic_runtime_resume(struct device *dev)
0026 {
0027     struct gic_chip_pm *chip_pm = dev_get_drvdata(dev);
0028     struct gic_chip_data *gic = chip_pm->chip_data;
0029     const struct gic_clk_data *data = chip_pm->clk_data;
0030     int ret;
0031
0032     ret = clk_bulk_prepare_enable(data->num_clocks, chip_pm->clks);
0033     if (ret)
0034         return ret;
0035
0036     /*
0037      * On the very first resume, the pointer to chip_pm->chip_data
0038      * will be NULL and this is intentional, because we do not
0039      * want to restore the GIC on the very first resume. So if
0040      * the pointer is not valid just return.
0041      */
0042     if (!gic)
0043         return 0;
0044
0045     gic_dist_restore(gic);
0046     gic_cpu_restore(gic);
0047
0048     return 0;
0049 }
0050
0051 static int gic_runtime_suspend(struct device *dev)
0052 {
0053     struct gic_chip_pm *chip_pm = dev_get_drvdata(dev);
0054     struct gic_chip_data *gic = chip_pm->chip_data;
0055     const struct gic_clk_data *data = chip_pm->clk_data;
0056
0057     gic_dist_save(gic);
0058     gic_cpu_save(gic);
0059
0060     clk_bulk_disable_unprepare(data->num_clocks, chip_pm->clks);
0061
0062     return 0;
0063 }
0064
0065 static int gic_probe(struct platform_device *pdev)
0066 {
0067     struct device *dev = &pdev->dev;
0068     const struct gic_clk_data *data;
0069     struct gic_chip_pm *chip_pm;
0070     int ret, irq, i;
0071
0072     data = of_device_get_match_data(&pdev->dev);
0073     if (!data) {
0074         dev_err(&pdev->dev, "no device match found\n");
0075         return -ENODEV;
0076     }
0077
0078     chip_pm = devm_kzalloc(dev, sizeof(*chip_pm), GFP_KERNEL);
0079     if (!chip_pm)
0080         return -ENOMEM;
0081
0082     irq = irq_of_parse_and_map(dev->of_node, 0);
0083     if (!irq) {
0084         dev_err(dev, "no parent interrupt found!\n");
0085         return -EINVAL;
0086     }
0087
0088     chip_pm->clks = devm_kcalloc(dev, data->num_clocks,
0089                      sizeof(*chip_pm->clks), GFP_KERNEL);
0090     if (!chip_pm->clks)
0091         return -ENOMEM;
0092
0093     for (i = 0; i < data->num_clocks; i++)
0094         chip_pm->clks[i].id = data->clocks[i];
0095
0096     ret = devm_clk_bulk_get(dev, data->num_clocks, chip_pm->clks);
0097     if (ret)
0098         goto irq_dispose;
0099
0100     chip_pm->clk_data = data;
0101     dev_set_drvdata(dev, chip_pm);
0102
0103     pm_runtime_enable(dev);
0104
0105     ret = pm_runtime_get_sync(dev);
0106     if (ret < 0)
0107         goto rpm_disable;
0108
0109     ret = gic_of_init_child(dev, &chip_pm->chip_data, irq);
0110     if (ret)
0111         goto rpm_put;
0112
0113     pm_runtime_put(dev);
0114
0115     dev_info(dev, "GIC IRQ controller registered\n");
0116
0117     return 0;
0118
0119 rpm_put:
0120     pm_runtime_put_sync(dev);
0121 rpm_disable:
0122     pm_runtime_disable(dev);
0123 irq_dispose:
0124     irq_dispose_mapping(irq);
0125
0126     return ret;
0127 }
0128
0129 static const struct dev_pm_ops gic_pm_ops = {
0130     SET_RUNTIME_PM_OPS(gic_runtime_suspend,
0131                gic_runtime_resume, NULL)
0132     SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
0133                      pm_runtime_force_resume)
0134 };
0135
0136 static const char * const gic400_clocks[] = {
0137     "clk",
0138 };
0139
0140 static const struct gic_clk_data gic400_data = {
0141     .num_clocks = ARRAY_SIZE(gic400_clocks),
0142     .clocks = gic400_clocks,
0143 };
0144
0145 static const struct of_device_id gic_match[] = {
0146     { .compatible = "nvidia,tegra210-agic", .data = &gic400_data },
0147     {},
0148 };
0149 MODULE_DEVICE_TABLE(of, gic_match);
0150
0151 static struct platform_driver gic_driver = {
0152     .probe      = gic_probe,
0153     .driver     = {
0154         .name   = "gic",
0155         .of_match_table = gic_match,
0156         .pm = &gic_pm_ops,
0157     }
0158 };
0159
0160 builtin_platform_driver(gic_driver);