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