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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2018-2019, Intel Corporation.4 * Copyright (C) 2012 Freescale Semiconductor, Inc.5 * Copyright (C) 2012 Linaro Ltd.6 *7 * Based on syscon driver.8 */9 10#include <linux/arm-smccc.h>11#include <linux/err.h>12#include <linux/io.h>13#include <linux/mfd/altera-sysmgr.h>14#include <linux/mfd/syscon.h>15#include <linux/module.h>16#include <linux/of.h>17#include <linux/platform_device.h>18#include <linux/regmap.h>19#include <linux/slab.h>20 21/**22 * struct altr_sysmgr - Altera SOCFPGA System Manager23 * @regmap: the regmap used for System Manager accesses.24 */25struct altr_sysmgr {26 struct regmap *regmap;27};28 29static struct platform_driver altr_sysmgr_driver;30 31/**32 * s10_protected_reg_write33 * Write to a protected SMC register.34 * @base: Base address of System Manager35 * @reg: Address offset of register36 * @val: Value to write37 * Return: INTEL_SIP_SMC_STATUS_OK (0) on success38 * INTEL_SIP_SMC_REG_ERROR on error39 * INTEL_SIP_SMC_RETURN_UNKNOWN_FUNCTION if not supported40 */41static int s10_protected_reg_write(void *base,42 unsigned int reg, unsigned int val)43{44 struct arm_smccc_res result;45 unsigned long sysmgr_base = (unsigned long)base;46 47 arm_smccc_smc(INTEL_SIP_SMC_REG_WRITE, sysmgr_base + reg,48 val, 0, 0, 0, 0, 0, &result);49 50 return (int)result.a0;51}52 53/**54 * s10_protected_reg_read55 * Read the status of a protected SMC register56 * @base: Base address of System Manager.57 * @reg: Address of register58 * @val: Value read.59 * Return: INTEL_SIP_SMC_STATUS_OK (0) on success60 * INTEL_SIP_SMC_REG_ERROR on error61 * INTEL_SIP_SMC_RETURN_UNKNOWN_FUNCTION if not supported62 */63static int s10_protected_reg_read(void *base,64 unsigned int reg, unsigned int *val)65{66 struct arm_smccc_res result;67 unsigned long sysmgr_base = (unsigned long)base;68 69 arm_smccc_smc(INTEL_SIP_SMC_REG_READ, sysmgr_base + reg,70 0, 0, 0, 0, 0, 0, &result);71 72 *val = (unsigned int)result.a1;73 74 return (int)result.a0;75}76 77static struct regmap_config altr_sysmgr_regmap_cfg = {78 .name = "altr_sysmgr",79 .reg_bits = 32,80 .reg_stride = 4,81 .val_bits = 32,82 .fast_io = true,83 .use_single_read = true,84 .use_single_write = true,85};86 87/**88 * altr_sysmgr_regmap_lookup_by_phandle89 * Find the sysmgr previous configured in probe() and return regmap property.90 * Return: regmap if found or error if not found.91 *92 * @np: Pointer to device's Device Tree node93 * @property: Device Tree property name which references the sysmgr94 */95struct regmap *altr_sysmgr_regmap_lookup_by_phandle(struct device_node *np,96 const char *property)97{98 struct device *dev;99 struct altr_sysmgr *sysmgr;100 struct device_node *sysmgr_np;101 102 if (property)103 sysmgr_np = of_parse_phandle(np, property, 0);104 else105 sysmgr_np = np;106 107 if (!sysmgr_np)108 return ERR_PTR(-ENODEV);109 110 dev = driver_find_device_by_of_node(&altr_sysmgr_driver.driver,111 (void *)sysmgr_np);112 if (property)113 of_node_put(sysmgr_np);114 115 if (!dev)116 return ERR_PTR(-EPROBE_DEFER);117 118 sysmgr = dev_get_drvdata(dev);119 120 return sysmgr->regmap;121}122EXPORT_SYMBOL_GPL(altr_sysmgr_regmap_lookup_by_phandle);123 124static int sysmgr_probe(struct platform_device *pdev)125{126 struct altr_sysmgr *sysmgr;127 struct regmap *regmap;128 struct resource *res;129 struct regmap_config sysmgr_config = altr_sysmgr_regmap_cfg;130 struct device *dev = &pdev->dev;131 struct device_node *np = dev->of_node;132 void __iomem *base;133 134 sysmgr = devm_kzalloc(dev, sizeof(*sysmgr), GFP_KERNEL);135 if (!sysmgr)136 return -ENOMEM;137 138 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);139 if (!res)140 return -ENOENT;141 142 sysmgr_config.max_register = resource_size(res) -143 sysmgr_config.reg_stride;144 if (of_device_is_compatible(np, "altr,sys-mgr-s10")) {145 sysmgr_config.reg_read = s10_protected_reg_read;146 sysmgr_config.reg_write = s10_protected_reg_write;147 148 /* Need physical address for SMCC call */149 regmap = devm_regmap_init(dev, NULL,150 (void *)(uintptr_t)res->start,151 &sysmgr_config);152 } else {153 base = devm_ioremap(dev, res->start, resource_size(res));154 if (!base)155 return -ENOMEM;156 157 sysmgr_config.max_register = resource_size(res) - 4;158 regmap = devm_regmap_init_mmio(dev, base, &sysmgr_config);159 }160 161 if (IS_ERR(regmap)) {162 pr_err("regmap init failed\n");163 return PTR_ERR(regmap);164 }165 166 sysmgr->regmap = regmap;167 168 platform_set_drvdata(pdev, sysmgr);169 170 return 0;171}172 173static const struct of_device_id altr_sysmgr_of_match[] = {174 { .compatible = "altr,sys-mgr" },175 { .compatible = "altr,sys-mgr-s10" },176 {},177};178MODULE_DEVICE_TABLE(of, altr_sysmgr_of_match);179 180static struct platform_driver altr_sysmgr_driver = {181 .probe = sysmgr_probe,182 .driver = {183 .name = "altr,system_manager",184 .of_match_table = altr_sysmgr_of_match,185 },186};187 188static int __init altr_sysmgr_init(void)189{190 return platform_driver_register(&altr_sysmgr_driver);191}192core_initcall(altr_sysmgr_init);193 194static void __exit altr_sysmgr_exit(void)195{196 platform_driver_unregister(&altr_sysmgr_driver);197}198module_exit(altr_sysmgr_exit);199 200MODULE_AUTHOR("Thor Thayer <>");201MODULE_DESCRIPTION("SOCFPGA System Manager driver");202