drivers/soc/versatile/soc-realview.c

   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 realview_get_manf(struct device *dev,
  43                               struct device_attribute *attr,
  44                               char *buf)
  45 {
  46         return sprintf(buf, "%02x\n", realview_coreid >> 24);
  47 }
  48
  49 static struct device_attribute realview_manf_attr =
  50         __ATTR(manufacturer,  S_IRUGO, realview_get_manf,  NULL);
  51
  52 static ssize_t realview_get_board(struct device *dev,
  53                               struct device_attribute *attr,
  54                               char *buf)
  55 {
  56         return sprintf(buf, "HBI-%03x\n", ((realview_coreid >> 16) & 0xfff));
  57 }
  58
  59 static struct device_attribute realview_board_attr =
  60         __ATTR(board,  S_IRUGO, realview_get_board,  NULL);
  61
  62 static ssize_t realview_get_arch(struct device *dev,
  63                               struct device_attribute *attr,
  64                               char *buf)
  65 {
  66         return sprintf(buf, "%s\n", realview_arch_str(realview_coreid));
  67 }
  68
  69 static struct device_attribute realview_arch_attr =
  70         __ATTR(fpga,  S_IRUGO, realview_get_arch,  NULL);
  71
  72 static ssize_t realview_get_build(struct device *dev,
  73                                struct device_attribute *attr,
  74                                char *buf)
  75 {
  76         return sprintf(buf, "%02x\n", (realview_coreid & 0xFF));
  77 }
  78
  79 static struct device_attribute realview_build_attr =
  80         __ATTR(build,  S_IRUGO, realview_get_build,  NULL);
  81
  82 static int realview_soc_probe(struct platform_device *pdev)
  83 {
  84         struct regmap *syscon_regmap;
  85         struct soc_device *soc_dev;
  86         struct soc_device_attribute *soc_dev_attr;
  87         struct device_node *np = pdev->dev.of_node;
  88         int ret;
  89
  90         syscon_regmap = syscon_regmap_lookup_by_phandle(np, "regmap");
  91         if (IS_ERR(syscon_regmap))
  92                 return PTR_ERR(syscon_regmap);
  93
  94         soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
  95         if (!soc_dev_attr)
  96                 return -ENOMEM;
  97
  98         ret = of_property_read_string(np, "compatible",
  99                                       &soc_dev_attr->soc_id);
 100         if (ret)
 101                 return -EINVAL;
 102
 103         soc_dev_attr->machine = "RealView";
 104         soc_dev_attr->family = "Versatile";
 105         soc_dev = soc_device_register(soc_dev_attr);
 106         if (IS_ERR(soc_dev)) {
 107                 kfree(soc_dev_attr);
 108                 return -ENODEV;
 109         }
 110         ret = regmap_read(syscon_regmap, REALVIEW_SYS_ID_OFFSET,
 111                           &realview_coreid);
 112         if (ret)
 113                 return -ENODEV;
 114
 115         device_create_file(soc_device_to_device(soc_dev), &realview_manf_attr);
 116         device_create_file(soc_device_to_device(soc_dev), &realview_board_attr);
 117         device_create_file(soc_device_to_device(soc_dev), &realview_arch_attr);
 118         device_create_file(soc_device_to_device(soc_dev), &realview_build_attr);
 119
 120         dev_info(&pdev->dev, "RealView Syscon Core ID: 0x%08x, HBI-%03x\n",
 121                  realview_coreid,
 122                  ((realview_coreid >> 16) & 0xfff));
 123         /* FIXME: add attributes for SoC to sysfs */
 124         return 0;
 125 }
 126
 127 static struct platform_driver realview_soc_driver = {
 128         .probe = realview_soc_probe,
 129         .driver = {
 130                 .name = "realview-soc",
 131                 .of_match_table = realview_soc_of_match,
 132         },
 133 };
 134 builtin_platform_driver(realview_soc_driver);