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1// SPDX-License-Identifier: GPL-2.02//3// Exynos Generic power domain support.4//5// Copyright (c) 2012 Samsung Electronics Co., Ltd.6// http://www.samsung.com7//8// Implementation of Exynos specific power domain control which is used in9// conjunction with runtime-pm. Support for both device-tree and non-device-tree10// based power domain support is included.11 12#include <linux/io.h>13#include <linux/err.h>14#include <linux/platform_device.h>15#include <linux/slab.h>16#include <linux/pm_domain.h>17#include <linux/delay.h>18#include <linux/of.h>19#include <linux/of_address.h>20#include <linux/pm_runtime.h>21 22struct exynos_pm_domain_config {23 /* Value for LOCAL_PWR_CFG and STATUS fields for each domain */24 u32 local_pwr_cfg;25};26 27/*28 * Exynos specific wrapper around the generic power domain29 */30struct exynos_pm_domain {31 void __iomem *base;32 struct generic_pm_domain pd;33 u32 local_pwr_cfg;34};35 36static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)37{38 struct exynos_pm_domain *pd;39 void __iomem *base;40 u32 timeout, pwr;41 char *op;42 43 pd = container_of(domain, struct exynos_pm_domain, pd);44 base = pd->base;45 46 pwr = power_on ? pd->local_pwr_cfg : 0;47 writel_relaxed(pwr, base);48 49 /* Wait max 1ms */50 timeout = 10;51 52 while ((readl_relaxed(base + 0x4) & pd->local_pwr_cfg) != pwr) {53 if (!timeout) {54 op = (power_on) ? "enable" : "disable";55 pr_err("Power domain %s %s failed\n", domain->name, op);56 return -ETIMEDOUT;57 }58 timeout--;59 cpu_relax();60 usleep_range(80, 100);61 }62 63 return 0;64}65 66static int exynos_pd_power_on(struct generic_pm_domain *domain)67{68 return exynos_pd_power(domain, true);69}70 71static int exynos_pd_power_off(struct generic_pm_domain *domain)72{73 return exynos_pd_power(domain, false);74}75 76static const struct exynos_pm_domain_config exynos4210_cfg = {77 .local_pwr_cfg = 0x7,78};79 80static const struct exynos_pm_domain_config exynos5433_cfg = {81 .local_pwr_cfg = 0xf,82};83 84static const struct of_device_id exynos_pm_domain_of_match[] = {85 {86 .compatible = "samsung,exynos4210-pd",87 .data = &exynos4210_cfg,88 }, {89 .compatible = "samsung,exynos5433-pd",90 .data = &exynos5433_cfg,91 },92 { },93};94 95static const char *exynos_get_domain_name(struct device_node *node)96{97 const char *name;98 99 if (of_property_read_string(node, "label", &name) < 0)100 name = kbasename(node->full_name);101 return kstrdup_const(name, GFP_KERNEL);102}103 104static int exynos_pd_probe(struct platform_device *pdev)105{106 const struct exynos_pm_domain_config *pm_domain_cfg;107 struct device *dev = &pdev->dev;108 struct device_node *np = dev->of_node;109 struct of_phandle_args child, parent;110 struct exynos_pm_domain *pd;111 int on, ret;112 113 pm_domain_cfg = of_device_get_match_data(dev);114 pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);115 if (!pd)116 return -ENOMEM;117 118 pd->pd.name = exynos_get_domain_name(np);119 if (!pd->pd.name)120 return -ENOMEM;121 122 pd->base = of_iomap(np, 0);123 if (!pd->base) {124 kfree_const(pd->pd.name);125 return -ENODEV;126 }127 128 pd->pd.power_off = exynos_pd_power_off;129 pd->pd.power_on = exynos_pd_power_on;130 pd->local_pwr_cfg = pm_domain_cfg->local_pwr_cfg;131 132 on = readl_relaxed(pd->base + 0x4) & pd->local_pwr_cfg;133 134 pm_genpd_init(&pd->pd, NULL, !on);135 ret = of_genpd_add_provider_simple(np, &pd->pd);136 137 if (ret == 0 && of_parse_phandle_with_args(np, "power-domains",138 "#power-domain-cells", 0, &parent) == 0) {139 child.np = np;140 child.args_count = 0;141 142 if (of_genpd_add_subdomain(&parent, &child))143 pr_warn("%pOF failed to add subdomain: %pOF\n",144 parent.np, child.np);145 else146 pr_info("%pOF has as child subdomain: %pOF.\n",147 parent.np, child.np);148 }149 150 pm_runtime_enable(dev);151 return ret;152}153 154static struct platform_driver exynos_pd_driver = {155 .probe = exynos_pd_probe,156 .driver = {157 .name = "exynos-pd",158 .of_match_table = exynos_pm_domain_of_match,159 .suppress_bind_attrs = true,160 }161};162 163static __init int exynos4_pm_init_power_domain(void)164{165 return platform_driver_register(&exynos_pd_driver);166}167core_initcall(exynos4_pm_init_power_domain);168