w83627ehf.rst (8637B)
1Kernel driver w83627ehf 2======================= 3 4Supported chips: 5 6 * Winbond W83627EHF/EHG (ISA access ONLY) 7 8 Prefix: 'w83627ehf' 9 10 Addresses scanned: ISA address retrieved from Super I/O registers 11 12 Datasheet: not available 13 14 * Winbond W83627DHG 15 16 Prefix: 'w83627dhg' 17 18 Addresses scanned: ISA address retrieved from Super I/O registers 19 20 Datasheet: not available 21 22 * Winbond W83627DHG-P 23 24 Prefix: 'w83627dhg' 25 26 Addresses scanned: ISA address retrieved from Super I/O registers 27 28 Datasheet: not available 29 30 * Winbond W83627UHG 31 32 Prefix: 'w83627uhg' 33 34 Addresses scanned: ISA address retrieved from Super I/O registers 35 36 Datasheet: available from www.nuvoton.com 37 38 * Winbond W83667HG 39 40 Prefix: 'w83667hg' 41 42 Addresses scanned: ISA address retrieved from Super I/O registers 43 44 Datasheet: not available 45 46 * Winbond W83667HG-B 47 48 Prefix: 'w83667hg' 49 50 Addresses scanned: ISA address retrieved from Super I/O registers 51 52 Datasheet: Available from Nuvoton upon request 53 54 * Nuvoton NCT6775F/W83667HG-I 55 56 Prefix: 'nct6775' 57 58 Addresses scanned: ISA address retrieved from Super I/O registers 59 60 Datasheet: Available from Nuvoton upon request 61 62 * Nuvoton NCT6776F 63 64 Prefix: 'nct6776' 65 66 Addresses scanned: ISA address retrieved from Super I/O registers 67 68 Datasheet: Available from Nuvoton upon request 69 70 71Authors: 72 73 - Jean Delvare <jdelvare@suse.de> 74 - Yuan Mu (Winbond) 75 - Rudolf Marek <r.marek@assembler.cz> 76 - David Hubbard <david.c.hubbard@gmail.com> 77 - Gong Jun <JGong@nuvoton.com> 78 79Description 80----------- 81 82This driver implements support for the Winbond W83627EHF, W83627EHG, 83W83627DHG, W83627DHG-P, W83627UHG, W83667HG, W83667HG-B, W83667HG-I 84(NCT6775F), and NCT6776F super I/O chips. We will refer to them collectively 85as Winbond chips. 86 87The chips implement 3 to 4 temperature sensors (9 for NCT6775F and NCT6776F), 882 to 5 fan rotation speed sensors, 8 to 10 analog voltage sensors, one VID 89(except for 627UHG), alarms with beep warnings (control unimplemented), 90and some automatic fan regulation strategies (plus manual fan control mode). 91 92The temperature sensor sources on W82677HG-B, NCT6775F, and NCT6776F are 93configurable. temp4 and higher attributes are only reported if its temperature 94source differs from the temperature sources of the already reported temperature 95sensors. The configured source for each of the temperature sensors is provided 96in tempX_label. 97 98Temperatures are measured in degrees Celsius and measurement resolution is 1 99degC for temp1 and 0.5 degC for temp2 and temp3. For temp4 and higher, 100resolution is 1 degC for W83667HG-B and 0.0 degC for NCT6775F and NCT6776F. 101An alarm is triggered when the temperature gets higher than high limit; 102it stays on until the temperature falls below the hysteresis value. 103Alarms are only supported for temp1, temp2, and temp3. 104 105Fan rotation speeds are reported in RPM (rotations per minute). An alarm is 106triggered if the rotation speed has dropped below a programmable limit. Fan 107readings can be divided by a programmable divider (1, 2, 4, 8, 16, 32, 64 or 108128) to give the readings more range or accuracy. The driver sets the most 109suitable fan divisor itself. Some fans might not be present because they 110share pins with other functions. 111 112Voltage sensors (also known as IN sensors) report their values in millivolts. 113An alarm is triggered if the voltage has crossed a programmable minimum 114or maximum limit. 115 116The driver supports automatic fan control mode known as Thermal Cruise. 117In this mode, the chip attempts to keep the measured temperature in a 118predefined temperature range. If the temperature goes out of range, fan 119is driven slower/faster to reach the predefined range again. 120 121The mode works for fan1-fan4. Mapping of temperatures to pwm outputs is as 122follows:: 123 124 temp1 -> pwm1 125 temp2 -> pwm2 126 temp3 -> pwm3 (not on 627UHG) 127 prog -> pwm4 (not on 667HG and 667HG-B; the programmable setting is not 128 supported by the driver) 129 130/sys files 131---------- 132 133name 134 this is a standard hwmon device entry, it contains the name of 135 the device (see the prefix in the list of supported devices at 136 the top of this file) 137 138pwm[1-4] 139 this file stores PWM duty cycle or DC value (fan speed) in range: 140 141 0 (stop) to 255 (full) 142 143pwm[1-4]_enable 144 this file controls mode of fan/temperature control: 145 146 * 1 Manual mode, write to pwm file any value 0-255 (full speed) 147 * 2 "Thermal Cruise" mode 148 * 3 "Fan Speed Cruise" mode 149 * 4 "Smart Fan III" mode 150 * 5 "Smart Fan IV" mode 151 152 SmartFan III mode is not supported on NCT6776F. 153 154 SmartFan IV mode is configurable only if it was configured at system 155 startup, and is only supported for W83677HG-B, NCT6775F, and NCT6776F. 156 SmartFan IV operational parameters can not be configured at this time, 157 and the various pwm attributes are not used in SmartFan IV mode. 158 The attributes can be written to, which is useful if you plan to 159 configure the system for a different pwm mode. However, the information 160 returned when reading pwm attributes is unrelated to SmartFan IV 161 operation. 162 163pwm[1-4]_mode 164 controls if output is PWM or DC level 165 166 * 0 DC output (0 - 12v) 167 * 1 PWM output 168 169Thermal Cruise mode 170------------------- 171 172If the temperature is in the range defined by: 173 174pwm[1-4]_target 175 set target temperature, unit millidegree Celsius 176 (range 0 - 127000) 177pwm[1-4]_tolerance 178 tolerance, unit millidegree Celsius (range 0 - 15000) 179 180there are no changes to fan speed. Once the temperature leaves the interval, 181fan speed increases (temp is higher) or decreases if lower than desired. 182There are defined steps and times, but not exported by the driver yet. 183 184pwm[1-4]_min_output 185 minimum fan speed (range 1 - 255), when the temperature 186 is below defined range. 187pwm[1-4]_stop_time 188 how many milliseconds [ms] must elapse to switch 189 corresponding fan off. (when the temperature was below 190 defined range). 191pwm[1-4]_start_output 192 minimum fan speed (range 1 - 255) when spinning up 193pwm[1-4]_step_output 194 rate of fan speed change (1 - 255) 195pwm[1-4]_stop_output 196 minimum fan speed (range 1 - 255) when spinning down 197pwm[1-4]_max_output 198 maximum fan speed (range 1 - 255), when the temperature 199 is above defined range. 200 201Note: last six functions are influenced by other control bits, not yet exported 202 by the driver, so a change might not have any effect. 203 204Implementation Details 205---------------------- 206 207Future driver development should bear in mind that the following registers have 208different functions on the 627EHF and the 627DHG. Some registers also have 209different power-on default values, but BIOS should already be loading 210appropriate defaults. Note that bank selection must be performed as is currently 211done in the driver for all register addresses. 212 213========================= ===================================================== 214Register(s) Meaning 215========================= ===================================================== 2160x49 only on DHG, selects temperature source for AUX fan, 217 CPU fan0 2180x4a not completely documented for the EHF and the DHG 219 documentation assigns different behavior to bits 7 220 and 6, including extending the temperature input 221 selection to SmartFan I, not just SmartFan III. 222 Testing on the EHF will reveal whether they are 223 compatible or not. 2240x58 Chip ID: 0xa1=EHF 0xc1=DHG 2250x5e only on DHG, has bits to enable "current mode" 226 temperature detection and critical temperature 227 protection 2280x45b only on EHF, bit 3, vin4 alarm (EHF supports 10 229 inputs, only 9 on DHG) 2300x552 only on EHF, vin4 2310x558 only on EHF, vin4 high limit 2320x559 only on EHF, vin4 low limit 2330x6b only on DHG, SYS fan critical temperature 2340x6c only on DHG, CPU fan0 critical temperature 2350x6d only on DHG, AUX fan critical temperature 2360x6e only on DHG, CPU fan1 critical temperature 2370x50-0x55 and 0x650-0x657 marked as: 238 239 - "Test Register" for the EHF 240 - "Reserved Register" for the DHG 241========================= ===================================================== 242 243The DHG also supports PECI, where the DHG queries Intel CPU temperatures, and 244the ICH8 southbridge gets that data via PECI from the DHG, so that the 245southbridge drives the fans. And the DHG supports SST, a one-wire serial bus. 246 247The DHG-P has an additional automatic fan speed control mode named Smart Fan 248(TM) III+. This mode is not yet supported by the driver.