1/*
  2 * Copyright (C) 2016 NVIDIA CORPORATION, All Rights Reserved.
  3 *
  4 * This program is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License version 2 as
  6 * published by the Free Software Foundation.
  7 *
  8 * This program is distributed in the hope that it will be useful,
  9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 11 * GNU General Public License for more details.
 12 *
 13 * You should have received a copy of the GNU General Public License
 14 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 15 */
 16#include <linux/module.h>
 17#include <linux/clk.h>
 18#include <linux/of_device.h>
 19#include <linux/of_irq.h>
 20#include <linux/irqchip/arm-gic.h>
 21#include <linux/platform_device.h>
 22#include <linux/pm_clock.h>
 23#include <linux/pm_runtime.h>
 24#include <linux/slab.h>
 25
 26struct gic_clk_data {
 27	unsigned int num_clocks;
 28	const char *const *clocks;
 29};
 30
 31static int gic_runtime_resume(struct device *dev)
 32{
 33	struct gic_chip_data *gic = dev_get_drvdata(dev);
 34	int ret;
 35
 36	ret = pm_clk_resume(dev);
 37	if (ret)
 38		return ret;
 39
 40	/*
 41	 * On the very first resume, the pointer to the driver data
 42	 * will be NULL and this is intentional, because we do not
 43	 * want to restore the GIC on the very first resume. So if
 44	 * the pointer is not valid just return.
 45	 */
 46	if (!gic)
 47		return 0;
 48
 49	gic_dist_restore(gic);
 50	gic_cpu_restore(gic);
 51
 52	return 0;
 53}
 54
 55static int gic_runtime_suspend(struct device *dev)
 56{
 57	struct gic_chip_data *gic = dev_get_drvdata(dev);
 58
 59	gic_dist_save(gic);
 60	gic_cpu_save(gic);
 61
 62	return pm_clk_suspend(dev);
 63}
 64
 65static int gic_get_clocks(struct device *dev, const struct gic_clk_data *data)
 66{
 67	unsigned int i;
 68	int ret;
 69
 70	if (!dev || !data)
 71		return -EINVAL;
 72
 73	ret = pm_clk_create(dev);
 74	if (ret)
 75		return ret;
 76
 77	for (i = 0; i < data->num_clocks; i++) {
 78		ret = of_pm_clk_add_clk(dev, data->clocks[i]);
 79		if (ret) {
 80			dev_err(dev, "failed to add clock %s\n",
 81				data->clocks[i]);
 82			pm_clk_destroy(dev);
 83			return ret;
 84		}
 85	}
 86
 87	return 0;
 88}
 89
 90static int gic_probe(struct platform_device *pdev)
 91{
 92	struct device *dev = &pdev->dev;
 93	const struct gic_clk_data *data;
 94	struct gic_chip_data *gic;
 95	int ret, irq;
 96
 97	data = of_device_get_match_data(&pdev->dev);
 98	if (!data) {
 99		dev_err(&pdev->dev, "no device match found\n");
100		return -ENODEV;
101	}
102
103	irq = irq_of_parse_and_map(dev->of_node, 0);
104	if (!irq) {
105		dev_err(dev, "no parent interrupt found!\n");
106		return -EINVAL;
107	}
108
109	ret = gic_get_clocks(dev, data);
110	if (ret)
111		goto irq_dispose;
112
113	pm_runtime_enable(dev);
114
115	ret = pm_runtime_get_sync(dev);
116	if (ret < 0)
117		goto rpm_disable;
118
119	ret = gic_of_init_child(dev, &gic, irq);
120	if (ret)
121		goto rpm_put;
122
123	platform_set_drvdata(pdev, gic);
124
125	pm_runtime_put(dev);
126
127	dev_info(dev, "GIC IRQ controller registered\n");
128
129	return 0;
130
131rpm_put:
132	pm_runtime_put_sync(dev);
133rpm_disable:
134	pm_runtime_disable(dev);
135	pm_clk_destroy(dev);
136irq_dispose:
137	irq_dispose_mapping(irq);
138
139	return ret;
140}
141
142static const struct dev_pm_ops gic_pm_ops = {
143	SET_RUNTIME_PM_OPS(gic_runtime_suspend,
144			   gic_runtime_resume, NULL)
145};
146
147static const char * const gic400_clocks[] = {
148	"clk",
149};
150
151static const struct gic_clk_data gic400_data = {
152	.num_clocks = ARRAY_SIZE(gic400_clocks),
153	.clocks = gic400_clocks,
154};
155
156static const struct of_device_id gic_match[] = {
157	{ .compatible = "nvidia,tegra210-agic",	.data = &gic400_data },
158	{},
159};
160MODULE_DEVICE_TABLE(of, gic_match);
161
162static struct platform_driver gic_driver = {
163	.probe		= gic_probe,
164	.driver		= {
165		.name	= "gic",
166		.of_match_table	= gic_match,
167		.pm	= &gic_pm_ops,
168	}
169};
170
171builtin_platform_driver(gic_driver);