drivers/soc/versatile/soc-realview.c

   1 /*
   2  * Copyright (C) 2014 Linaro Ltd.
   3  *
   4  * Author: Linus Walleij <linus.walleij@linaro.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2, as
   8  * published by the Free Software Foundation.
   9  *
  10  */
  11 #include <linux/init.h>
  12 #include <linux/io.h>
  13 #include <linux/slab.h>
  14 #include <linux/sys_soc.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/mfd/syscon.h>
  17 #include <linux/regmap.h>
  18 #include <linux/of.h>
  19
  20 /* System ID in syscon */
  21 #define REALVIEW_SYS_ID_OFFSET 0x00
  22
  23 static const struct of_device_id realview_soc_of_match[] = {
  24         { .compatible = "arm,realview-eb-soc",  },
  25         { .compatible = "arm,realview-pb1176-soc", },
  26         { .compatible = "arm,realview-pb11mp-soc", },
  27         { .compatible = "arm,realview-pba8-soc", },
  28         { .compatible = "arm,realview-pbx-soc", },
  29         { }
  30 };
  31
  32 static u32 realview_coreid;
  33
  34 static const char *realview_board_str(u32 id)
  35 {
  36         switch ((id >> 16) & 0xfff) {
  37         case 0x0147:
  38                 return "HBI-0147";
  39         case 0x0159:
  40                 return "HBI-0159";
  41         default:
  42                 return "Unknown";
  43         }
  44 }
  45
  46 static const char *realview_arch_str(u32 id)
  47 {
  48         switch ((id >> 8) & 0xf) {
  49         case 0x04:
  50                 return "AHB";
  51         case 0x05:
  52                 return "Multi-layer AXI";
  53         default:
  54                 return "Unknown";
  55         }
  56 }
  57
  58 static ssize_t realview_get_manf(struct device *dev,
  59                               struct device_attribute *attr,
  60                               char *buf)
  61 {
  62         return sprintf(buf, "%02x\n", realview_coreid >> 24);
  63 }
  64
  65 static struct device_attribute realview_manf_attr =
  66         __ATTR(manufacturer,  S_IRUGO, realview_get_manf,  NULL);
  67
  68 static ssize_t realview_get_board(struct device *dev,
  69                               struct device_attribute *attr,
  70                               char *buf)
  71 {
  72         return sprintf(buf, "%s\n", realview_board_str(realview_coreid));
  73 }
  74
  75 static struct device_attribute realview_board_attr =
  76         __ATTR(board,  S_IRUGO, realview_get_board,  NULL);
  77
  78 static ssize_t realview_get_arch(struct device *dev,
  79                               struct device_attribute *attr,
  80                               char *buf)
  81 {
  82         return sprintf(buf, "%s\n", realview_arch_str(realview_coreid));
  83 }
  84
  85 static struct device_attribute realview_arch_attr =
  86         __ATTR(fpga,  S_IRUGO, realview_get_arch,  NULL);
  87
  88 static ssize_t realview_get_build(struct device *dev,
  89                                struct device_attribute *attr,
  90                                char *buf)
  91 {
  92         return sprintf(buf, "%02x\n", (realview_coreid & 0xFF));
  93 }
  94
  95 static struct device_attribute realview_build_attr =
  96         __ATTR(build,  S_IRUGO, realview_get_build,  NULL);
  97
  98 static int realview_soc_probe(struct platform_device *pdev)
  99 {
 100         static struct regmap *syscon_regmap;
 101         struct soc_device *soc_dev;
 102         struct soc_device_attribute *soc_dev_attr;
 103         struct device_node *np = pdev->dev.of_node;
 104         int ret;
 105
 106         syscon_regmap = syscon_regmap_lookup_by_phandle(np, "regmap");
 107         if (IS_ERR(syscon_regmap))
 108                 return PTR_ERR(syscon_regmap);
 109
 110         soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
 111         if (!soc_dev_attr)
 112                 return -ENOMEM;
 113
 114         ret = of_property_read_string(np, "compatible",
 115                                       &soc_dev_attr->soc_id);
 116         if (ret)
 117                 return -EINVAL;
 118
 119         soc_dev_attr->machine = "RealView";
 120         soc_dev_attr->family = "Versatile";
 121         soc_dev = soc_device_register(soc_dev_attr);
 122         if (IS_ERR(soc_dev)) {
 123                 kfree(soc_dev_attr);
 124                 return -ENODEV;
 125         }
 126         ret = regmap_read(syscon_regmap, REALVIEW_SYS_ID_OFFSET,
 127                           &realview_coreid);
 128         if (ret)
 129                 return -ENODEV;
 130
 131         device_create_file(soc_device_to_device(soc_dev), &realview_manf_attr);
 132         device_create_file(soc_device_to_device(soc_dev), &realview_board_attr);
 133         device_create_file(soc_device_to_device(soc_dev), &realview_arch_attr);
 134         device_create_file(soc_device_to_device(soc_dev), &realview_build_attr);
 135
 136         dev_info(&pdev->dev, "RealView Syscon Core ID: 0x%08x\n",
 137                  realview_coreid);
 138         /* FIXME: add attributes for SoC to sysfs */
 139         return 0;
 140 }
 141
 142 static struct platform_driver realview_soc_driver = {
 143         .probe = realview_soc_probe,
 144         .driver = {
 145                 .name = "realview-soc",
 146                 .of_match_table = realview_soc_of_match,
 147         },
 148 };
 149 builtin_platform_driver(realview_soc_driver);