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 static u32 realview_coreid;
  32
  33 static const char *realview_board_str(u32 id)
  34 {
  35         switch ((id >> 16) & 0xfff) {
  36         case 0x0147:
  37                 return "HBI-0147";
  38         default:
  39                 return "Unknown";
  40         }
  41 }
  42
  43 static const char *realview_arch_str(u32 id)
  44 {
  45         switch ((id >> 8) & 0xf) {
  46         case 0x05:
  47                 return "Multi-layer AXI";
  48         default:
  49                 return "Unknown";
  50         }
  51 }
  52
  53 static ssize_t realview_get_manf(struct device *dev,
  54                               struct device_attribute *attr,
  55                               char *buf)
  56 {
  57         return sprintf(buf, "%02x\n", realview_coreid >> 24);
  58 }
  59
  60 static struct device_attribute realview_manf_attr =
  61         __ATTR(manufacturer,  S_IRUGO, realview_get_manf,  NULL);
  62
  63 static ssize_t realview_get_board(struct device *dev,
  64                               struct device_attribute *attr,
  65                               char *buf)
  66 {
  67         return sprintf(buf, "%s\n", realview_board_str(realview_coreid));
  68 }
  69
  70 static struct device_attribute realview_board_attr =
  71         __ATTR(board,  S_IRUGO, realview_get_board,  NULL);
  72
  73 static ssize_t realview_get_arch(struct device *dev,
  74                               struct device_attribute *attr,
  75                               char *buf)
  76 {
  77         return sprintf(buf, "%s\n", realview_arch_str(realview_coreid));
  78 }
  79
  80 static struct device_attribute realview_arch_attr =
  81         __ATTR(fpga,  S_IRUGO, realview_get_arch,  NULL);
  82
  83 static ssize_t realview_get_build(struct device *dev,
  84                                struct device_attribute *attr,
  85                                char *buf)
  86 {
  87         return sprintf(buf, "%02x\n", (realview_coreid & 0xFF));
  88 }
  89
  90 static struct device_attribute realview_build_attr =
  91         __ATTR(build,  S_IRUGO, realview_get_build,  NULL);
  92
  93 static int realview_soc_probe(struct platform_device *pdev)
  94 {
  95         static struct regmap *syscon_regmap;
  96         struct soc_device *soc_dev;
  97         struct soc_device_attribute *soc_dev_attr;
  98         struct device_node *np = pdev->dev.of_node;
  99         int ret;
 100
 101         syscon_regmap = syscon_regmap_lookup_by_phandle(np, "regmap");
 102         if (IS_ERR(syscon_regmap))
 103                 return PTR_ERR(syscon_regmap);
 104
 105         soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
 106         if (!soc_dev_attr)
 107                 return -ENOMEM;
 108
 109         ret = of_property_read_string(np, "compatible",
 110                                       &soc_dev_attr->soc_id);
 111         if (ret)
 112                 return -EINVAL;
 113
 114         soc_dev_attr->machine = "RealView";
 115         soc_dev_attr->family = "Versatile";
 116         soc_dev = soc_device_register(soc_dev_attr);
 117         if (IS_ERR(soc_dev)) {
 118                 kfree(soc_dev_attr);
 119                 return -ENODEV;
 120         }
 121         ret = regmap_read(syscon_regmap, REALVIEW_SYS_ID_OFFSET,
 122                           &realview_coreid);
 123         if (ret)
 124                 return -ENODEV;
 125
 126         device_create_file(soc_device_to_device(soc_dev), &realview_manf_attr);
 127         device_create_file(soc_device_to_device(soc_dev), &realview_board_attr);
 128         device_create_file(soc_device_to_device(soc_dev), &realview_arch_attr);
 129         device_create_file(soc_device_to_device(soc_dev), &realview_build_attr);
 130
 131         dev_info(&pdev->dev, "RealView Syscon Core ID: 0x%08x\n",
 132                  realview_coreid);
 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 module_platform_driver(realview_soc_driver);