arch/tile/kernel/sysfs.c

   1 /*
   2  * Copyright 2011 Tilera Corporation. All Rights Reserved.
   3  *
   4  *   This program is free software; you can redistribute it and/or
   5  *   modify it under the terms of the GNU General Public License
   6  *   as published by the Free Software Foundation, version 2.
   7  *
   8  *   This program is distributed in the hope that it will be useful, but
   9  *   WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  11  *   NON INFRINGEMENT.  See the GNU General Public License for
  12  *   more details.
  13  *
  14  * /sys entry support.
  15  */
  16
  17 #include <linux/device.h>
  18 #include <linux/cpu.h>
  19 #include <linux/slab.h>
  20 #include <linux/smp.h>
  21 #include <linux/stat.h>
  22 #include <hv/hypervisor.h>
  23
  24 /* Return a string queried from the hypervisor, truncated to page size. */
  25 static ssize_t get_hv_confstr(char *page, int query)
  26 {
  27         ssize_t n = hv_confstr(query, (unsigned long)page, PAGE_SIZE - 1);
  28         n = n < 0 ? 0 : min(n, (ssize_t)PAGE_SIZE - 1) - 1;
  29         if (n)
  30                 page[n++] = '\n';
  31         page[n] = '\0';
  32         return n;
  33 }
  34
  35 static ssize_t chip_width_show(struct device *dev,
  36                                struct device_attribute *attr,
  37                                char *page)
  38 {
  39         return sprintf(page, "%u\n", smp_width);
  40 }
  41 static DEVICE_ATTR(chip_width, 0444, chip_width_show, NULL);
  42
  43 static ssize_t chip_height_show(struct device *dev,
  44                                 struct device_attribute *attr,
  45                                 char *page)
  46 {
  47         return sprintf(page, "%u\n", smp_height);
  48 }
  49 static DEVICE_ATTR(chip_height, 0444, chip_height_show, NULL);
  50
  51 static ssize_t chip_serial_show(struct device *dev,
  52                                 struct device_attribute *attr,
  53                                 char *page)
  54 {
  55         return get_hv_confstr(page, HV_CONFSTR_CHIP_SERIAL_NUM);
  56 }
  57 static DEVICE_ATTR(chip_serial, 0444, chip_serial_show, NULL);
  58
  59 static ssize_t chip_revision_show(struct device *dev,
  60                                   struct device_attribute *attr,
  61                                   char *page)
  62 {
  63         return get_hv_confstr(page, HV_CONFSTR_CHIP_REV);
  64 }
  65 static DEVICE_ATTR(chip_revision, 0444, chip_revision_show, NULL);
  66
  67
  68 static ssize_t type_show(struct device *dev,
  69                             struct device_attribute *attr,
  70                             char *page)
  71 {
  72         return sprintf(page, "tilera\n");
  73 }
  74 static DEVICE_ATTR(type, 0444, type_show, NULL);
  75
  76 #define HV_CONF_ATTR(name, conf)                                        \
  77         static ssize_t name ## _show(struct device *dev,                \
  78                                      struct device_attribute *attr, \
  79                                      char *page)                        \
  80         {                                                               \
  81                 return get_hv_confstr(page, conf);                      \
  82         }                                                               \
  83         static DEVICE_ATTR(name, 0444, name ## _show, NULL);
  84
  85 HV_CONF_ATTR(version,           HV_CONFSTR_HV_SW_VER)
  86 HV_CONF_ATTR(config_version,    HV_CONFSTR_HV_CONFIG_VER)
  87
  88 HV_CONF_ATTR(board_part,        HV_CONFSTR_BOARD_PART_NUM)
  89 HV_CONF_ATTR(board_serial,      HV_CONFSTR_BOARD_SERIAL_NUM)
  90 HV_CONF_ATTR(board_revision,    HV_CONFSTR_BOARD_REV)
  91 HV_CONF_ATTR(board_description, HV_CONFSTR_BOARD_DESC)
  92 HV_CONF_ATTR(mezz_part,         HV_CONFSTR_MEZZ_PART_NUM)
  93 HV_CONF_ATTR(mezz_serial,       HV_CONFSTR_MEZZ_SERIAL_NUM)
  94 HV_CONF_ATTR(mezz_revision,     HV_CONFSTR_MEZZ_REV)
  95 HV_CONF_ATTR(mezz_description,  HV_CONFSTR_MEZZ_DESC)
  96 HV_CONF_ATTR(switch_control,    HV_CONFSTR_SWITCH_CONTROL)
  97
  98 static struct attribute *board_attrs[] = {
  99         &dev_attr_board_part.attr,
 100         &dev_attr_board_serial.attr,
 101         &dev_attr_board_revision.attr,
 102         &dev_attr_board_description.attr,
 103         &dev_attr_mezz_part.attr,
 104         &dev_attr_mezz_serial.attr,
 105         &dev_attr_mezz_revision.attr,
 106         &dev_attr_mezz_description.attr,
 107         &dev_attr_switch_control.attr,
 108         NULL
 109 };
 110
 111 static struct attribute_group board_attr_group = {
 112         .name   = "board",
 113         .attrs  = board_attrs,
 114 };
 115
 116
 117 static struct bin_attribute hvconfig_bin;
 118
 119 static ssize_t
 120 hvconfig_bin_read(struct file *filp, struct kobject *kobj,
 121                   struct bin_attribute *bin_attr,
 122                   char *buf, loff_t off, size_t count)
 123 {
 124         static size_t size;
 125
 126         /* Lazily learn the true size (minus the trailing NUL). */
 127         if (size == 0)
 128                 size = hv_confstr(HV_CONFSTR_HV_CONFIG, 0, 0) - 1;
 129
 130         /* Check and adjust input parameters. */
 131         if (off > size)
 132                 return -EINVAL;
 133         if (count > size - off)
 134                 count = size - off;
 135
 136         if (count) {
 137                 /* Get a copy of the hvc and copy out the relevant portion. */
 138                 char *hvc;
 139
 140                 size = off + count;
 141                 hvc = kmalloc(size, GFP_KERNEL);
 142                 if (hvc == NULL)
 143                         return -ENOMEM;
 144                 hv_confstr(HV_CONFSTR_HV_CONFIG, (unsigned long)hvc, size);
 145                 memcpy(buf, hvc + off, count);
 146                 kfree(hvc);
 147         }
 148
 149         return count;
 150 }
 151
 152 static int __init create_sysfs_entries(void)
 153 {
 154         int err = 0;
 155
 156 #define create_cpu_attr(name)                                           \
 157         if (!err)                                                       \
 158                 err = device_create_file(cpu_subsys.dev_root, &dev_attr_##name);
 159         create_cpu_attr(chip_width);
 160         create_cpu_attr(chip_height);
 161         create_cpu_attr(chip_serial);
 162         create_cpu_attr(chip_revision);
 163
 164 #define create_hv_attr(name)                                            \
 165         if (!err)                                                       \
 166                 err = sysfs_create_file(hypervisor_kobj, &dev_attr_##name.attr);
 167         create_hv_attr(type);
 168         create_hv_attr(version);
 169         create_hv_attr(config_version);
 170
 171         if (!err)
 172                 err = sysfs_create_group(hypervisor_kobj, &board_attr_group);
 173
 174         if (!err) {
 175                 sysfs_bin_attr_init(&hvconfig_bin);
 176                 hvconfig_bin.attr.name = "hvconfig";
 177                 hvconfig_bin.attr.mode = S_IRUGO;
 178                 hvconfig_bin.read = hvconfig_bin_read;
 179                 hvconfig_bin.size = PAGE_SIZE;
 180                 err = sysfs_create_bin_file(hypervisor_kobj, &hvconfig_bin);
 181         }
 182
 183         return err;
 184 }
 185 subsys_initcall(create_sysfs_entries);