1 // SPDX-License-Identifier: GPL-2.0 2 /* 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 Manager 23 * @regmap: the regmap used for System Manager accesses. 24 */ 25 struct altr_sysmgr { 26 struct regmap *regmap; 27 }; 28 29 static struct platform_driver altr_sysmgr_driver; 30 31 /** 32 * s10_protected_reg_write 33 * Write to a protected SMC register. 34 * @base: Base address of System Manager 35 * @reg: Address offset of register 36 * @val: Value to write 37 * Return: INTEL_SIP_SMC_STATUS_OK (0) on success 38 * INTEL_SIP_SMC_REG_ERROR on error 39 * INTEL_SIP_SMC_RETURN_UNKNOWN_FUNCTION if not supported 40 */ 41 static 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_read 55 * Read the status of a protected SMC register 56 * @base: Base address of System Manager. 57 * @reg: Address of register 58 * @val: Value read. 59 * Return: INTEL_SIP_SMC_STATUS_OK (0) on success 60 * INTEL_SIP_SMC_REG_ERROR on error 61 * INTEL_SIP_SMC_RETURN_UNKNOWN_FUNCTION if not supported 62 */ 63 static 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 77 static 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_phandle 89 * 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 node 93 * @property: Device Tree property name which references the sysmgr 94 */ 95 struct 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 else 105 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 of_node_put(sysmgr_np); 113 if (!dev) 114 return ERR_PTR(-EPROBE_DEFER); 115 116 sysmgr = dev_get_drvdata(dev); 117 118 return sysmgr->regmap; 119 } 120 EXPORT_SYMBOL_GPL(altr_sysmgr_regmap_lookup_by_phandle); 121 122 static int sysmgr_probe(struct platform_device *pdev) 123 { 124 struct altr_sysmgr *sysmgr; 125 struct regmap *regmap; 126 struct resource *res; 127 struct regmap_config sysmgr_config = altr_sysmgr_regmap_cfg; 128 struct device *dev = &pdev->dev; 129 struct device_node *np = dev->of_node; 130 void __iomem *base; 131 132 sysmgr = devm_kzalloc(dev, sizeof(*sysmgr), GFP_KERNEL); 133 if (!sysmgr) 134 return -ENOMEM; 135 136 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 137 if (!res) 138 return -ENOENT; 139 140 sysmgr_config.max_register = resource_size(res) - 141 sysmgr_config.reg_stride; 142 if (of_device_is_compatible(np, "altr,sys-mgr-s10")) { 143 sysmgr_config.reg_read = s10_protected_reg_read; 144 sysmgr_config.reg_write = s10_protected_reg_write; 145 146 /* Need physical address for SMCC call */ 147 regmap = devm_regmap_init(dev, NULL, 148 (void *)(uintptr_t)res->start, 149 &sysmgr_config); 150 } else { 151 base = devm_ioremap(dev, res->start, resource_size(res)); 152 if (!base) 153 return -ENOMEM; 154 155 sysmgr_config.max_register = resource_size(res) - 4; 156 regmap = devm_regmap_init_mmio(dev, base, &sysmgr_config); 157 } 158 159 if (IS_ERR(regmap)) { 160 pr_err("regmap init failed\n"); 161 return PTR_ERR(regmap); 162 } 163 164 sysmgr->regmap = regmap; 165 166 platform_set_drvdata(pdev, sysmgr); 167 168 return 0; 169 } 170 171 static const struct of_device_id altr_sysmgr_of_match[] = { 172 { .compatible = "altr,sys-mgr" }, 173 { .compatible = "altr,sys-mgr-s10" }, 174 {}, 175 }; 176 MODULE_DEVICE_TABLE(of, altr_sysmgr_of_match); 177 178 static struct platform_driver altr_sysmgr_driver = { 179 .probe = sysmgr_probe, 180 .driver = { 181 .name = "altr,system_manager", 182 .of_match_table = altr_sysmgr_of_match, 183 }, 184 }; 185 186 static int __init altr_sysmgr_init(void) 187 { 188 return platform_driver_register(&altr_sysmgr_driver); 189 } 190 core_initcall(altr_sysmgr_init); 191 192 static void __exit altr_sysmgr_exit(void) 193 { 194 platform_driver_unregister(&altr_sysmgr_driver); 195 } 196 module_exit(altr_sysmgr_exit); 197 198 MODULE_AUTHOR("Thor Thayer <>"); 199 MODULE_DESCRIPTION("SOCFPGA System Manager driver"); 200