1===================== 2Kernel driver asc7621 3===================== 4 5Supported chips: 6 7 Andigilog aSC7621 and aSC7621a 8 9 Prefix: 'asc7621' 10 11 Addresses scanned: I2C 0x2c, 0x2d, 0x2e 12 13 Datasheet: http://www.fairview5.com/linux/asc7621/asc7621.pdf 14 15Author: 16 George Joseph 17 18Description provided by Dave Pivin @ Andigilog: 19 20Andigilog has both the PECI and pre-PECI versions of the Heceta-6, as 21Intel calls them. Heceta-6e has high frequency PWM and Heceta-6p has 22added PECI and a 4th thermal zone. The Andigilog aSC7611 is the 23Heceta-6e part and aSC7621 is the Heceta-6p part. They are both in 24volume production, shipping to Intel and their subs. 25 26We have enhanced both parts relative to the governing Intel 27specification. First enhancement is temperature reading resolution. We 28have used registers below 20h for vendor-specific functions in addition 29to those in the Intel-specified vendor range. 30 31Our conversion process produces a result that is reported as two bytes. 32The fan speed control uses this finer value to produce a "step-less" fan 33PWM output. These two bytes are "read-locked" to guarantee that once a 34high or low byte is read, the other byte is locked-in until after the 35next read of any register. So to get an atomic reading, read high or low 36byte, then the very next read should be the opposite byte. Our data 37sheet says 10-bits of resolution, although you may find the lower bits 38are active, they are not necessarily reliable or useful externally. We 39chose not to mask them. 40 41We employ significant filtering that is user tunable as described in the 42data sheet. Our temperature reports and fan PWM outputs are very smooth 43when compared to the competition, in addition to the higher resolution 44temperature reports. The smoother PWM output does not require user 45intervention. 46 47We offer GPIO features on the former VID pins. These are open-drain 48outputs or inputs and may be used as general purpose I/O or as alarm 49outputs that are based on temperature limits. These are in 19h and 1Ah. 50 51We offer flexible mapping of temperature readings to thermal zones. Any 52temperature may be mapped to any zone, which has a default assignment 53that follows Intel's specs. 54 55Since there is a fan to zone assignment that allows for the "hotter" of 56a set of zones to control the PWM of an individual fan, but there is no 57indication to the user, we have added an indicator that shows which zone 58is currently controlling the PWM for a given fan. This is in register 5900h. 60 61Both remote diode temperature readings may be given an offset value such 62that the reported reading as well as the temperature used to determine 63PWM may be offset for system calibration purposes. 64 65PECI Extended configuration allows for having more than two domains per 66PECI address and also provides an enabling function for each PECI 67address. One could use our flexible zone assignment to have a zone 68assigned to up to 4 PECI addresses. This is not possible in the default 69Intel configuration. This would be useful in multi-CPU systems with 70individual fans on each that would benefit from individual fan control. 71This is in register 0Eh. 72 73The tachometer measurement system is flexible and able to adapt to many 74fan types. We can also support pulse-stretched PWM so that 3-wire fans 75may be used. These characteristics are in registers 04h to 07h. 76 77Finally, we have added a tach disable function that turns off the tach 78measurement system for individual tachs in order to save power. That is 79in register 75h. 80 81-------------------------------------------------------------------------- 82 83aSC7621 Product Description 84=========================== 85 86The aSC7621 has a two wire digital interface compatible with SMBus 2.0. 87Using a 10-bit ADC, the aSC7621 measures the temperature of two remote diode 88connected transistors as well as its own die. Support for Platform 89Environmental Control Interface (PECI) is included. 90 91Using temperature information from these four zones, an automatic fan speed 92control algorithm is employed to minimize acoustic impact while achieving 93recommended CPU temperature under varying operational loads. 94 95To set fan speed, the aSC7621 has three independent pulse width modulation 96(PWM) outputs that are controlled by one, or a combination of three, 97temperature zones. Both high- and low-frequency PWM ranges are supported. 98 99The aSC7621 also includes a digital filter that can be invoked to smooth 100temperature readings for better control of fan speed and minimum acoustic 101impact. 102 103The aSC7621 has tachometer inputs to measure fan speed on up to four fans. 104Limit and status registers for all measured values are included to alert 105the system host that any measurements are outside of programmed limits 106via status registers. 107 108System voltages of VCCP, 2.5V, 3.3V, 5.0V, and 12V motherboard power are 109monitored efficiently with internal scaling resistors. 110 111Features 112-------- 113 114- Supports PECI interface and monitors internal and remote thermal diodes 115- 2-wire, SMBus 2.0 compliant, serial interface 116- 10-bit ADC 117- Monitors VCCP, 2.5V, 3.3V, 5.0V, and 12V motherboard/processor supplies 118- Programmable autonomous fan control based on temperature readings 119- Noise filtering of temperature reading for fan speed control 120- 0.25C digital temperature sensor resolution 121- 3 PWM fan speed control outputs for 2-, 3- or 4-wire fans and up to 4 fan 122 tachometer inputs 123- Enhanced measured temperature to Temperature Zone assignment. 124- Provides high and low PWM frequency ranges 125- 3 GPIO pins for custom use 126- 24-Lead QSOP package 127 128Configuration Notes 129=================== 130 131Except where noted below, the sysfs entries created by this driver follow 132the standards defined in "sysfs-interface". 133 134temp1_source 135 = =============================================== 136 0 (default) peci_legacy = 0, Remote 1 Temperature 137 peci_legacy = 1, PECI Processor Temperature 0 138 1 Remote 1 Temperature 139 2 Remote 2 Temperature 140 3 Internal Temperature 141 4 PECI Processor Temperature 0 142 5 PECI Processor Temperature 1 143 6 PECI Processor Temperature 2 144 7 PECI Processor Temperature 3 145 = =============================================== 146 147temp2_source 148 = =============================================== 149 0 (default) Internal Temperature 150 1 Remote 1 Temperature 151 2 Remote 2 Temperature 152 3 Internal Temperature 153 4 PECI Processor Temperature 0 154 5 PECI Processor Temperature 1 155 6 PECI Processor Temperature 2 156 7 PECI Processor Temperature 3 157 = =============================================== 158 159temp3_source 160 = =============================================== 161 0 (default) Remote 2 Temperature 162 1 Remote 1 Temperature 163 2 Remote 2 Temperature 164 3 Internal Temperature 165 4 PECI Processor Temperature 0 166 5 PECI Processor Temperature 1 167 6 PECI Processor Temperature 2 168 7 PECI Processor Temperature 3 169 = =============================================== 170 171temp4_source 172 = =============================================== 173 0 (default) peci_legacy = 0, PECI Processor Temperature 0 174 peci_legacy = 1, Remote 1 Temperature 175 1 Remote 1 Temperature 176 2 Remote 2 Temperature 177 3 Internal Temperature 178 4 PECI Processor Temperature 0 179 5 PECI Processor Temperature 1 180 6 PECI Processor Temperature 2 181 7 PECI Processor Temperature 3 182 = =============================================== 183 184temp[1-4]_smoothing_enable / temp[1-4]_smoothing_time 185 Smooths spikes in temp readings caused by noise. 186 Valid values in milliseconds are: 187 188 * 35000 189 * 17600 190 * 11800 191 * 7000 192 * 4400 193 * 3000 194 * 1600 195 * 800 196 197temp[1-4]_crit 198 When the corresponding zone temperature reaches this value, 199 ALL pwm outputs will got to 100%. 200 201temp[5-8]_input / temp[5-8]_enable 202 The aSC7621 can also read temperatures provided by the processor 203 via the PECI bus. Usually these are "core" temps and are relative 204 to the point where the automatic thermal control circuit starts 205 throttling. This means that these are usually negative numbers. 206 207pwm[1-3]_enable 208 =============== ======================================================== 209 0 Fan off. 210 1 Fan on manual control. 211 2 Fan on automatic control and will run at the minimum pwm 212 if the temperature for the zone is below the minimum. 213 3 Fan on automatic control but will be off if the 214 temperature for the zone is below the minimum. 215 4-254 Ignored. 216 255 Fan on full. 217 =============== ======================================================== 218 219pwm[1-3]_auto_channels 220 Bitmap as described in sysctl-interface with the following 221 exceptions... 222 223 Only the following combination of zones (and their corresponding masks) 224 are valid: 225 226 * 1 227 * 2 228 * 3 229 * 2,3 230 * 1,2,3 231 * 4 232 * 1,2,3,4 233 234 * Special values: 235 236 == ====================== 237 0 Disabled. 238 16 Fan on manual control. 239 31 Fan on full. 240 == ====================== 241 242 243pwm[1-3]_invert 244 When set, inverts the meaning of pwm[1-3]. 245 i.e. when pwm = 0, the fan will be on full and 246 when pwm = 255 the fan will be off. 247 248pwm[1-3]_freq 249 PWM frequency in Hz 250 Valid values in Hz are: 251 252 * 10 253 * 15 254 * 23 255 * 30 (default) 256 * 38 257 * 47 258 * 62 259 * 94 260 * 23000 261 * 24000 262 * 25000 263 * 26000 264 * 27000 265 * 28000 266 * 29000 267 * 30000 268 269 Setting any other value will be ignored. 270 271peci_enable 272 Enables or disables PECI 273 274peci_avg 275 Input filter average time. 276 277 * 0 0 Sec. (no Smoothing) (default) 278 * 1 0.25 Sec. 279 * 2 0.5 Sec. 280 * 3 1.0 Sec. 281 * 4 2.0 Sec. 282 * 5 4.0 Sec. 283 * 6 8.0 Sec. 284 * 7 0.0 Sec. 285 286peci_legacy 287 = ============================================ 288 0 Standard Mode (default) 289 Remote Diode 1 reading is associated with 290 Temperature Zone 1, PECI is associated with 291 Zone 4 292 293 1 Legacy Mode 294 PECI is associated with Temperature Zone 1, 295 Remote Diode 1 is associated with Zone 4 296 = ============================================ 297 298peci_diode 299 Diode filter 300 301 = ==================== 302 0 0.25 Sec. 303 1 1.1 Sec. 304 2 2.4 Sec. (default) 305 3 3.4 Sec. 306 4 5.0 Sec. 307 5 6.8 Sec. 308 6 10.2 Sec. 309 7 16.4 Sec. 310 = ==================== 311 312peci_4domain 313 Four domain enable 314 315 = =============================================== 316 0 1 or 2 Domains for enabled processors (default) 317 1 3 or 4 Domains for enabled processors 318 = =============================================== 319 320peci_domain 321 Domain 322 323 = ================================================== 324 0 Processor contains a single domain (0) (default) 325 1 Processor contains two domains (0,1) 326 = ================================================== 327