1 #pragma once 2 3 #include <filesystem> 4 #include <string> 5 #include <vector> 6 7 namespace witherspoon 8 { 9 namespace pmbus 10 { 11 12 namespace fs = std::filesystem; 13 14 // The file name Linux uses to capture the STATUS_WORD from pmbus. 15 constexpr auto STATUS_WORD = "status0"; 16 17 // The file name Linux uses to capture the STATUS_INPUT from pmbus. 18 constexpr auto STATUS_INPUT = "status0_input"; 19 20 // Voltage out status. 21 // Overvoltage fault or warning, Undervoltage fault or warning, maximum or 22 // minimum warning, .... 23 // Uses Page substitution 24 constexpr auto STATUS_VOUT = "statusP_vout"; 25 26 namespace status_vout 27 { 28 // Mask of bits that are only warnings 29 constexpr auto WARNING_MASK = 0x6A; 30 } // namespace status_vout 31 32 // Current output status bits. 33 constexpr auto STATUS_IOUT = "status0_iout"; 34 35 // Manufacturing specific status bits 36 constexpr auto STATUS_MFR = "status0_mfr"; 37 38 // Reports on the status of any fans installed in position 1 and 2. 39 constexpr auto STATUS_FANS_1_2 = "status0_fans12"; 40 41 // Reports on temperature faults or warnings. Overtemperature fault, 42 // overtemperature warning, undertemperature warning, undertemperature fault. 43 constexpr auto STATUS_TEMPERATURE = "status0_temp"; 44 45 namespace status_word 46 { 47 constexpr auto VOUT_FAULT = 0x8000; 48 49 // The IBM CFF power supply driver does map this bit to power1_alarm in the 50 // hwmon space, but since the other bits that need to be checked do not have 51 // a similar mapping, the code will just read STATUS_WORD and use bit masking 52 // to see if the INPUT FAULT OR WARNING bit is on. 53 constexpr auto INPUT_FAULT_WARN = 0x2000; 54 55 // The bit mask representing the POWER_GOOD Negated bit of the STATUS_WORD. 56 constexpr auto POWER_GOOD_NEGATED = 0x0800; 57 58 // The bit mask representing the FAN FAULT or WARNING bit of the STATUS_WORD. 59 // Bit 2 of the high byte of STATUS_WORD. 60 constexpr auto FAN_FAULT = 0x0400; 61 62 // The bit mask representing the UNITI_IS_OFF bit of the STATUS_WORD. 63 constexpr auto UNIT_IS_OFF = 0x0040; 64 65 // Bit 5 of the STATUS_BYTE, or lower byte of STATUS_WORD is used to indicate 66 // an output overvoltage fault. 67 constexpr auto VOUT_OV_FAULT = 0x0020; 68 69 // The bit mask representing that an output overcurrent fault has occurred. 70 constexpr auto IOUT_OC_FAULT = 0x0010; 71 72 // The IBM CFF power supply driver does map this bit to in1_alarm, however, 73 // since a number of the other bits are not mapped that way for STATUS_WORD, 74 // this code will just read the entire STATUS_WORD and use bit masking to find 75 // out if that fault is on. 76 constexpr auto VIN_UV_FAULT = 0x0008; 77 78 // The bit mask representing the TEMPERATURE FAULT or WARNING bit of the 79 // STATUS_WORD. Bit 2 of the low byte (STATUS_BYTE). 80 constexpr auto TEMPERATURE_FAULT_WARN = 0x0004; 81 82 } // namespace status_word 83 84 namespace status_temperature 85 { 86 // Overtemperature Fault 87 constexpr auto OT_FAULT = 0x80; 88 } // namespace status_temperature 89 90 /** 91 * Where the access should be done 92 */ 93 enum class Type 94 { 95 Base, // base device directory 96 Hwmon, // hwmon directory 97 Debug, // pmbus debug directory 98 DeviceDebug, // device debug directory 99 HwmonDeviceDebug // hwmon device debug directory 100 }; 101 102 /** 103 * @class PMBus 104 * 105 * This class is an interface to communicating with PMBus devices 106 * by reading and writing sysfs files. 107 * 108 * Based on the Type parameter, the accesses can either be done 109 * in the base device directory (the one passed into the constructor), 110 * or in the hwmon directory for the device. 111 */ 112 class PMBus 113 { 114 public: 115 PMBus() = delete; 116 ~PMBus() = default; 117 PMBus(const PMBus&) = default; 118 PMBus& operator=(const PMBus&) = default; 119 PMBus(PMBus&&) = default; 120 PMBus& operator=(PMBus&&) = default; 121 122 /** 123 * Constructor 124 * 125 * @param[in] path - path to the sysfs directory 126 */ 127 PMBus(const std::string& path) : basePath(path) 128 { 129 findHwmonDir(); 130 } 131 132 /** 133 * Constructor 134 * 135 * This version is required when DeviceDebug 136 * access will be used. 137 * 138 * @param[in] path - path to the sysfs directory 139 * @param[in] driverName - the device driver name 140 * @param[in] instance - chip instance number 141 */ 142 PMBus(const std::string& path, const std::string& driverName, 143 size_t instance) : 144 basePath(path), 145 driverName(driverName), instance(instance) 146 { 147 findHwmonDir(); 148 } 149 150 /** 151 * Reads a file in sysfs that represents a single bit, 152 * therefore doing a PMBus read. 153 * 154 * @param[in] name - path concatenated to 155 * basePath to read 156 * @param[in] type - Path type 157 * 158 * @return bool - false if result was 0, else true 159 */ 160 bool readBit(const std::string& name, Type type); 161 162 /** 163 * Reads a file in sysfs that represents a single bit, 164 * where the page number passed in is substituted 165 * into the name in place of the 'P' character in it. 166 * 167 * @param[in] name - path concatenated to 168 * basePath to read 169 * @param[in] page - page number 170 * @param[in] type - Path type 171 * 172 * @return bool - false if result was 0, else true 173 */ 174 bool readBitInPage(const std::string& name, size_t page, Type type); 175 /** 176 * Checks if the file for the given name and type exists. 177 * 178 * @param[in] name - path concatenated to basePath to read 179 * @param[in] type - Path type 180 * 181 * @return bool - True if file exists, false if it does not. 182 */ 183 bool exists(const std::string& name, Type type); 184 185 /** 186 * Read byte(s) from file in sysfs. 187 * 188 * @param[in] name - path concatenated to basePath to read 189 * @param[in] type - Path type 190 * 191 * @return uint64_t - Up to 8 bytes of data read from file. 192 */ 193 uint64_t read(const std::string& name, Type type); 194 195 /** 196 * Read a string from file in sysfs. 197 * 198 * @param[in] name - path concatenated to basePath to read 199 * @param[in] type - Path type 200 * 201 * @return string - The data read from the file. 202 */ 203 std::string readString(const std::string& name, Type type); 204 205 /** 206 * Read data from a binary file in sysfs. 207 * 208 * @param[in] name - path concatenated to basePath to read 209 * @param[in] type - Path type 210 * @param[in] length - length of data to read, in bytes 211 * 212 * @return vector<uint8_t> - The data read from the file. 213 */ 214 std::vector<uint8_t> readBinary(const std::string& name, Type type, 215 size_t length); 216 217 /** 218 * Writes an integer value to the file, therefore doing 219 * a PMBus write. 220 * 221 * @param[in] name - path concatenated to 222 * basePath to write 223 * @param[in] value - the value to write 224 * @param[in] type - Path type 225 */ 226 void write(const std::string& name, int value, Type type); 227 228 /** 229 * Returns the sysfs base path of this device 230 */ 231 inline const auto& path() const 232 { 233 return basePath; 234 } 235 236 /** 237 * Replaces the 'P' in the string passed in with 238 * the page number passed in. 239 * 240 * For example: 241 * insertPageNum("inP_enable", 42) 242 * returns "in42_enable" 243 * 244 * @param[in] templateName - the name string, with a 'P' in it 245 * @param[in] page - the page number to insert where the P was 246 * 247 * @return string - the new string with the page number in it 248 */ 249 static std::string insertPageNum(const std::string& templateName, 250 size_t page); 251 252 /** 253 * Finds the path relative to basePath to the hwmon directory 254 * for the device and stores it in hwmonRelPath. 255 */ 256 void findHwmonDir(); 257 258 /** 259 * Returns the path to use for the passed in type. 260 * 261 * @param[in] type - Path type 262 * 263 * @return fs::path - the full path 264 */ 265 fs::path getPath(Type type); 266 267 private: 268 /** 269 * Returns the device name 270 * 271 * This is found in the 'name' file in basePath. 272 * 273 * @return string - the device name 274 */ 275 std::string getDeviceName(); 276 277 /** 278 * The sysfs device path 279 */ 280 fs::path basePath; 281 282 /** 283 * The directory name under the basePath hwmon directory 284 */ 285 fs::path hwmonDir; 286 287 /** 288 * The device driver name. Used for finding the device 289 * debug directory. Not required if that directory 290 * isn't used. 291 */ 292 std::string driverName; 293 294 /** 295 * The device instance number. 296 * 297 * Used in conjunction with the driver name for finding 298 * the debug directory. Not required if that directory 299 * isn't used. 300 */ 301 size_t instance = 0; 302 303 /** 304 * The pmbus debug path with status files 305 */ 306 const fs::path debugPath = "/sys/kernel/debug/"; 307 }; 308 309 } // namespace pmbus 310 } // namespace witherspoon 311