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1// SPDX-License-Identifier: GPL-2.02//3// rcpm.c - Freescale QorIQ RCPM driver4//5// Copyright 2019-2020 NXP6//7// Author: Ran Wang <ran.wang_1@nxp.com>8 9#include <linux/init.h>10#include <linux/module.h>11#include <linux/platform_device.h>12#include <linux/of_address.h>13#include <linux/slab.h>14#include <linux/suspend.h>15#include <linux/kernel.h>16#include <linux/acpi.h>17 18#define RCPM_WAKEUP_CELL_MAX_SIZE 719 20struct rcpm {21 unsigned int wakeup_cells;22 void __iomem *ippdexpcr_base;23 bool little_endian;24};25 26#define SCFG_SPARECR8 0x051c27 28static void copy_ippdexpcr1_setting(u32 val)29{30 struct device_node *np;31 void __iomem *regs;32 u32 reg_val;33 34 np = of_find_compatible_node(NULL, NULL, "fsl,ls1021a-scfg");35 if (!np)36 return;37 38 regs = of_iomap(np, 0);39 if (!regs)40 return;41 42 reg_val = ioread32be(regs + SCFG_SPARECR8);43 iowrite32be(val | reg_val, regs + SCFG_SPARECR8);44 45 iounmap(regs);46}47 48/**49 * rcpm_pm_prepare - performs device-level tasks associated with power50 * management, such as programming related to the wakeup source control.51 * @dev: Device to handle.52 *53 */54static int rcpm_pm_prepare(struct device *dev)55{56 int i, ret, idx;57 void __iomem *base;58 struct wakeup_source *ws;59 struct rcpm *rcpm;60 struct device_node *np = dev->of_node;61 u32 value[RCPM_WAKEUP_CELL_MAX_SIZE + 1];62 u32 setting[RCPM_WAKEUP_CELL_MAX_SIZE] = {0};63 64 rcpm = dev_get_drvdata(dev);65 if (!rcpm)66 return -EINVAL;67 68 base = rcpm->ippdexpcr_base;69 idx = wakeup_sources_read_lock();70 71 /* Begin with first registered wakeup source */72 for_each_wakeup_source(ws) {73 74 /* skip object which is not attached to device */75 if (!ws->dev || !ws->dev->parent)76 continue;77 78 ret = device_property_read_u32_array(ws->dev->parent,79 "fsl,rcpm-wakeup", value,80 rcpm->wakeup_cells + 1);81 82 if (ret)83 continue;84 85 /*86 * For DT mode, would handle devices with "fsl,rcpm-wakeup"87 * pointing to the current RCPM node.88 *89 * For ACPI mode, currently we assume there is only one90 * RCPM controller existing.91 */92 if (is_of_node(dev->fwnode))93 if (np->phandle != value[0])94 continue;95 96 /* Property "#fsl,rcpm-wakeup-cells" of rcpm node defines the97 * number of IPPDEXPCR register cells, and "fsl,rcpm-wakeup"98 * of wakeup source IP contains an integer array: <phandle to99 * RCPM node, IPPDEXPCR0 setting, IPPDEXPCR1 setting,100 * IPPDEXPCR2 setting, etc>.101 *102 * So we will go thought them to collect setting data.103 */104 for (i = 0; i < rcpm->wakeup_cells; i++)105 setting[i] |= value[i + 1];106 }107 108 wakeup_sources_read_unlock(idx);109 110 /* Program all IPPDEXPCRn once */111 for (i = 0; i < rcpm->wakeup_cells; i++) {112 u32 tmp = setting[i];113 void __iomem *address = base + i * 4;114 115 if (!tmp)116 continue;117 118 /* We can only OR related bits */119 if (rcpm->little_endian) {120 tmp |= ioread32(address);121 iowrite32(tmp, address);122 } else {123 tmp |= ioread32be(address);124 iowrite32be(tmp, address);125 }126 /*127 * Workaround of errata A-008646 on SoC LS1021A:128 * There is a bug of register ippdexpcr1.129 * Reading configuration register RCPM_IPPDEXPCR1130 * always return zero. So save ippdexpcr1's value131 * to register SCFG_SPARECR8.And the value of132 * ippdexpcr1 will be read from SCFG_SPARECR8.133 */134 if (dev_of_node(dev) && (i == 1))135 if (of_device_is_compatible(np, "fsl,ls1021a-rcpm"))136 copy_ippdexpcr1_setting(tmp);137 }138 139 return 0;140}141 142static const struct dev_pm_ops rcpm_pm_ops = {143 .prepare = rcpm_pm_prepare,144};145 146static int rcpm_probe(struct platform_device *pdev)147{148 struct device *dev = &pdev->dev;149 struct rcpm *rcpm;150 int ret;151 152 rcpm = devm_kzalloc(dev, sizeof(*rcpm), GFP_KERNEL);153 if (!rcpm)154 return -ENOMEM;155 156 rcpm->ippdexpcr_base = devm_platform_ioremap_resource(pdev, 0);157 if (IS_ERR(rcpm->ippdexpcr_base)) {158 ret = PTR_ERR(rcpm->ippdexpcr_base);159 return ret;160 }161 162 rcpm->little_endian = device_property_read_bool(163 &pdev->dev, "little-endian");164 165 ret = device_property_read_u32(&pdev->dev,166 "#fsl,rcpm-wakeup-cells", &rcpm->wakeup_cells);167 if (ret)168 return ret;169 170 dev_set_drvdata(&pdev->dev, rcpm);171 172 return 0;173}174 175static const struct of_device_id rcpm_of_match[] = {176 { .compatible = "fsl,qoriq-rcpm-2.1+", },177 {}178};179MODULE_DEVICE_TABLE(of, rcpm_of_match);180 181#ifdef CONFIG_ACPI182static const struct acpi_device_id rcpm_acpi_ids[] = {183 {"NXP0015",},184 { }185};186MODULE_DEVICE_TABLE(acpi, rcpm_acpi_ids);187#endif188 189static struct platform_driver rcpm_driver = {190 .driver = {191 .name = "rcpm",192 .of_match_table = rcpm_of_match,193 .acpi_match_table = ACPI_PTR(rcpm_acpi_ids),194 .pm = &rcpm_pm_ops,195 },196 .probe = rcpm_probe,197};198 199module_platform_driver(rcpm_driver);200