1// SPDX-License-Identifier: GPL-2.0 2// 3// rcpm.c - Freescale QorIQ RCPM driver 4// 5// Copyright 2019-2020 NXP 6// 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 7 19 20struct rcpm { 21 unsigned int wakeup_cells; 22 void __iomem *ippdexpcr_base; 23 bool little_endian; 24}; 25 26#define SCFG_SPARECR8 0x051c 27 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 power 50 * 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 one 90 * 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 the 97 * number of IPPDEXPCR register cells, and "fsl,rcpm-wakeup" 98 * of wakeup source IP contains an integer array: <phandle to 99 * 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_IPPDEXPCR1 130 * always return zero. So save ippdexpcr1's value 131 * to register SCFG_SPARECR8.And the value of 132 * 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_ACPI 182static const struct acpi_device_id rcpm_acpi_ids[] = { 183 {"NXP0015",}, 184 { } 185}; 186MODULE_DEVICE_TABLE(acpi, rcpm_acpi_ids); 187#endif 188 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