1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2014 Linaro Ltd. 4 * 5 * Author: Linus Walleij <linus.walleij@linaro.org> 6 */ 7 #include <linux/device.h> 8 #include <linux/init.h> 9 #include <linux/io.h> 10 #include <linux/slab.h> 11 #include <linux/sys_soc.h> 12 #include <linux/platform_device.h> 13 #include <linux/mfd/syscon.h> 14 #include <linux/regmap.h> 15 #include <linux/of.h> 16 17 /* System ID in syscon */ 18 #define REALVIEW_SYS_ID_OFFSET 0x00 19 20 static const struct of_device_id realview_soc_of_match[] = { 21 { .compatible = "arm,realview-eb-soc", }, 22 { .compatible = "arm,realview-pb1176-soc", }, 23 { .compatible = "arm,realview-pb11mp-soc", }, 24 { .compatible = "arm,realview-pba8-soc", }, 25 { .compatible = "arm,realview-pbx-soc", }, 26 { } 27 }; 28 29 static u32 realview_coreid; 30 31 static const char *realview_arch_str(u32 id) 32 { 33 switch ((id >> 8) & 0xf) { 34 case 0x04: 35 return "AHB"; 36 case 0x05: 37 return "Multi-layer AXI"; 38 default: 39 return "Unknown"; 40 } 41 } 42 43 static ssize_t 44 manufacturer_show(struct device *dev, struct device_attribute *attr, char *buf) 45 { 46 return sprintf(buf, "%02x\n", realview_coreid >> 24); 47 } 48 49 static DEVICE_ATTR_RO(manufacturer); 50 51 static ssize_t 52 board_show(struct device *dev, struct device_attribute *attr, char *buf) 53 { 54 return sprintf(buf, "HBI-%03x\n", ((realview_coreid >> 16) & 0xfff)); 55 } 56 57 static DEVICE_ATTR_RO(board); 58 59 static ssize_t 60 fpga_show(struct device *dev, struct device_attribute *attr, char *buf) 61 { 62 return sprintf(buf, "%s\n", realview_arch_str(realview_coreid)); 63 } 64 65 static DEVICE_ATTR_RO(fpga); 66 67 static ssize_t 68 build_show(struct device *dev, struct device_attribute *attr, char *buf) 69 { 70 return sprintf(buf, "%02x\n", (realview_coreid & 0xFF)); 71 } 72 73 static DEVICE_ATTR_RO(build); 74 75 static struct attribute *realview_attrs[] = { 76 &dev_attr_manufacturer.attr, 77 &dev_attr_board.attr, 78 &dev_attr_fpga.attr, 79 &dev_attr_build.attr, 80 NULL 81 }; 82 83 ATTRIBUTE_GROUPS(realview); 84 85 static void realview_soc_socdev_release(void *data) 86 { 87 struct soc_device *soc_dev = data; 88 89 soc_device_unregister(soc_dev); 90 } 91 92 static int realview_soc_probe(struct platform_device *pdev) 93 { 94 struct regmap *syscon_regmap; 95 struct soc_device *soc_dev; 96 struct soc_device_attribute *soc_dev_attr; 97 struct device_node *np = pdev->dev.of_node; 98 int ret; 99 100 syscon_regmap = syscon_regmap_lookup_by_phandle(np, "regmap"); 101 if (IS_ERR(syscon_regmap)) 102 return PTR_ERR(syscon_regmap); 103 104 soc_dev_attr = devm_kzalloc(&pdev->dev, sizeof(*soc_dev_attr), GFP_KERNEL); 105 if (!soc_dev_attr) 106 return -ENOMEM; 107 108 ret = of_property_read_string(np, "compatible", 109 &soc_dev_attr->soc_id); 110 if (ret) 111 return -EINVAL; 112 113 soc_dev_attr->machine = "RealView"; 114 soc_dev_attr->family = "Versatile"; 115 soc_dev_attr->custom_attr_group = realview_groups[0]; 116 soc_dev = soc_device_register(soc_dev_attr); 117 if (IS_ERR(soc_dev)) 118 return -ENODEV; 119 120 ret = devm_add_action_or_reset(&pdev->dev, realview_soc_socdev_release, 121 soc_dev); 122 if (ret) 123 return ret; 124 125 ret = regmap_read(syscon_regmap, REALVIEW_SYS_ID_OFFSET, 126 &realview_coreid); 127 if (ret) 128 return -ENODEV; 129 130 dev_info(&pdev->dev, "RealView Syscon Core ID: 0x%08x, HBI-%03x\n", 131 realview_coreid, 132 ((realview_coreid >> 16) & 0xfff)); 133 /* FIXME: add attributes for SoC to sysfs */ 134 return 0; 135 } 136 137 static struct platform_driver realview_soc_driver = { 138 .probe = realview_soc_probe, 139 .driver = { 140 .name = "realview-soc", 141 .of_match_table = realview_soc_of_match, 142 }, 143 }; 144 builtin_platform_driver(realview_soc_driver); 145