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(cpumod_part,       HV_CONFSTR_CPUMOD_PART_NUM)
  97 HV_CONF_ATTR(cpumod_serial,     HV_CONFSTR_CPUMOD_SERIAL_NUM)
  98 HV_CONF_ATTR(cpumod_revision,   HV_CONFSTR_CPUMOD_REV)
  99 HV_CONF_ATTR(cpumod_description,HV_CONFSTR_CPUMOD_DESC)
 100 HV_CONF_ATTR(switch_control,    HV_CONFSTR_SWITCH_CONTROL)
 101
 102 static struct attribute *board_attrs[] = {
 103         &dev_attr_board_part.attr,
 104         &dev_attr_board_serial.attr,
 105         &dev_attr_board_revision.attr,
 106         &dev_attr_board_description.attr,
 107         &dev_attr_mezz_part.attr,
 108         &dev_attr_mezz_serial.attr,
 109         &dev_attr_mezz_revision.attr,
 110         &dev_attr_mezz_description.attr,
 111         &dev_attr_cpumod_part.attr,
 112         &dev_attr_cpumod_serial.attr,
 113         &dev_attr_cpumod_revision.attr,
 114         &dev_attr_cpumod_description.attr,
 115         &dev_attr_switch_control.attr,
 116         NULL
 117 };
 118
 119 static struct attribute_group board_attr_group = {
 120         .name   = "board",
 121         .attrs  = board_attrs,
 122 };
 123
 124
 125 static struct bin_attribute hvconfig_bin;
 126
 127 static ssize_t
 128 hvconfig_bin_read(struct file *filp, struct kobject *kobj,
 129                   struct bin_attribute *bin_attr,
 130                   char *buf, loff_t off, size_t count)
 131 {
 132         static size_t size;
 133
 134         /* Lazily learn the true size (minus the trailing NUL). */
 135         if (size == 0)
 136                 size = hv_confstr(HV_CONFSTR_HV_CONFIG, 0, 0) - 1;
 137
 138         /* Check and adjust input parameters. */
 139         if (off > size)
 140                 return -EINVAL;
 141         if (count > size - off)
 142                 count = size - off;
 143
 144         if (count) {
 145                 /* Get a copy of the hvc and copy out the relevant portion. */
 146                 char *hvc;
 147
 148                 size = off + count;
 149                 hvc = kmalloc(size, GFP_KERNEL);
 150                 if (hvc == NULL)
 151                         return -ENOMEM;
 152                 hv_confstr(HV_CONFSTR_HV_CONFIG, (unsigned long)hvc, size);
 153                 memcpy(buf, hvc + off, count);
 154                 kfree(hvc);
 155         }
 156
 157         return count;
 158 }
 159
 160 static ssize_t hv_stats_show(struct device *dev,
 161                              struct device_attribute *attr,
 162                              char *page)
 163 {
 164         int cpu = dev->id;
 165         long lotar = HV_XY_TO_LOTAR(cpu_x(cpu), cpu_y(cpu));
 166
 167         ssize_t n = hv_confstr(HV_CONFSTR_HV_STATS,
 168                                (unsigned long)page, PAGE_SIZE - 1,
 169                                lotar, 0);
 170         n = n < 0 ? 0 : min(n, (ssize_t)PAGE_SIZE - 1);
 171         page[n] = '\0';
 172         return n;
 173 }
 174
 175 static ssize_t hv_stats_store(struct device *dev,
 176                               struct device_attribute *attr,
 177                               const char *page,
 178                               size_t count)
 179 {
 180         int cpu = dev->id;
 181         long lotar = HV_XY_TO_LOTAR(cpu_x(cpu), cpu_y(cpu));
 182
 183         ssize_t n = hv_confstr(HV_CONFSTR_HV_STATS, 0, 0, lotar, 1);
 184         return n < 0 ? n : count;
 185 }
 186
 187 static DEVICE_ATTR(hv_stats, 0644, hv_stats_show, hv_stats_store);
 188
 189 static int hv_stats_device_add(struct device *dev, struct subsys_interface *sif)
 190 {
 191         int err, cpu = dev->id;
 192
 193         if (!cpu_online(cpu))
 194                 return 0;
 195
 196         err = sysfs_create_file(&dev->kobj, &dev_attr_hv_stats.attr);
 197
 198         return err;
 199 }
 200
 201 static int hv_stats_device_remove(struct device *dev,
 202                                   struct subsys_interface *sif)
 203 {
 204         int cpu = dev->id;
 205
 206         if (!cpu_online(cpu))
 207                 return 0;
 208
 209         sysfs_remove_file(&dev->kobj, &dev_attr_hv_stats.attr);
 210         return 0;
 211 }
 212
 213
 214 static struct subsys_interface hv_stats_interface = {
 215         .name                   = "hv_stats",
 216         .subsys                 = &cpu_subsys,
 217         .add_dev                = hv_stats_device_add,
 218         .remove_dev             = hv_stats_device_remove,
 219 };
 220
 221 static int __init create_sysfs_entries(void)
 222 {
 223         int err = 0;
 224
 225 #define create_cpu_attr(name)                                           \
 226         if (!err)                                                       \
 227                 err = device_create_file(cpu_subsys.dev_root, &dev_attr_##name);
 228         create_cpu_attr(chip_width);
 229         create_cpu_attr(chip_height);
 230         create_cpu_attr(chip_serial);
 231         create_cpu_attr(chip_revision);
 232
 233 #define create_hv_attr(name)                                            \
 234         if (!err)                                                       \
 235                 err = sysfs_create_file(hypervisor_kobj, &dev_attr_##name.attr);
 236         create_hv_attr(type);
 237         create_hv_attr(version);
 238         create_hv_attr(config_version);
 239
 240         if (!err)
 241                 err = sysfs_create_group(hypervisor_kobj, &board_attr_group);
 242
 243         if (!err) {
 244                 sysfs_bin_attr_init(&hvconfig_bin);
 245                 hvconfig_bin.attr.name = "hvconfig";
 246                 hvconfig_bin.attr.mode = S_IRUGO;
 247                 hvconfig_bin.read = hvconfig_bin_read;
 248                 hvconfig_bin.size = PAGE_SIZE;
 249                 err = sysfs_create_bin_file(hypervisor_kobj, &hvconfig_bin);
 250         }
 251
 252         if (!err) {
 253                 /*
 254                  * Don't bother adding the hv_stats files on each CPU if
 255                  * our hypervisor doesn't supply statistics.
 256                  */
 257                 int cpu = raw_smp_processor_id();
 258                 long lotar = HV_XY_TO_LOTAR(cpu_x(cpu), cpu_y(cpu));
 259                 char dummy;
 260                 ssize_t n = hv_confstr(HV_CONFSTR_HV_STATS,
 261                                        (unsigned long) &dummy, 1,
 262                                        lotar, 0);
 263                 if (n >= 0)
 264                         err = subsys_interface_register(&hv_stats_interface);
 265         }
 266
 267         return err;
 268 }
 269 subsys_initcall(create_sysfs_entries);