projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 65afb4c8 VP |
1 | Kernel driver mlxreg-fan |
| 2 | ======================== | |
| 3 | ||
| 4 | Provides FAN control for the next Mellanox systems: | |
| 5 | QMB700, equipped with 40x200GbE InfiniBand ports; | |
| 6 | MSN3700, equipped with 32x200GbE or 16x400GbE Ethernet ports; | |
| 7 | MSN3410, equipped with 6x400GbE plus 48x50GbE Ethernet ports; | |
| 8 | MSN3800, equipped with 64x1000GbE Ethernet ports; | |
| 9 | These are the Top of the Rack systems, equipped with Mellanox switch | |
| 10 | board with Mellanox Quantum or Spectrume-2 devices. | |
| 11 | FAN controller is implemented by the programmable device logic. | |
| 12 | ||
| 13 | The default registers offsets set within the programmable device is as | |
| 14 | following: | |
| 15 | - pwm1 0xe3 | |
| 16 | - fan1 (tacho1) 0xe4 | |
| 17 | - fan2 (tacho2) 0xe5 | |
| 18 | - fan3 (tacho3) 0xe6 | |
| 19 | - fan4 (tacho4) 0xe7 | |
| 20 | - fan5 (tacho5) 0xe8 | |
| 21 | - fan6 (tacho6) 0xe9 | |
| 22 | - fan7 (tacho7) 0xea | |
| 23 | - fan8 (tacho8) 0xeb | |
| 24 | - fan9 (tacho9) 0xec | |
| 25 | - fan10 (tacho10) 0xed | |
| 26 | - fan11 (tacho11) 0xee | |
| 27 | - fan12 (tacho12) 0xef | |
| 28 | This setup can be re-programmed with other registers. | |
| 29 | ||
| 30 | Author: Vadim Pasternak <vadimp@mellanox.com> | |
| 31 | ||
| 32 | Description | |
| 33 | ----------- | |
| 34 | ||
| 35 | The driver implements a simple interface for driving a fan connected to | |
| 36 | a PWM output and tachometer inputs. | |
| 37 | This driver obtains PWM and tachometers registers location according to | |
| 38 | the system configuration and creates FAN/PWM hwmon objects and a cooling | |
| 39 | device. PWM and tachometers are sensed through the on-board programmable | |
| 40 | device, which exports its register map. This device could be attached to | |
| 41 | any bus type, for which register mapping is supported. | |
| 42 | Single instance is created with one PWM control, up to 12 tachometers and | |
| 43 | one cooling device. It could be as many instances as programmable device | |
| 44 | supports. | |
| 45 | The driver exposes the fan to the user space through the hwmon's and | |
| 46 | thermal's sysfs interfaces. | |
| 47 | ||
| 48 | /sys files in hwmon subsystem | |
| 49 | ----------------------------- | |
| 50 | ||
| 51 | fan[1-12]_fault - RO files for tachometers TACH1-TACH12 fault indication | |
| 52 | fan[1-12]_input - RO files for tachometers TACH1-TACH12 input (in RPM) | |
| 53 | pwm1 - RW file for fan[1-12] target duty cycle (0..255) | |
| 54 | ||
| 55 | /sys files in thermal subsystem | |
| 56 | ------------------------------- | |
| 57 | ||
| 58 | cur_state - RW file for current cooling state of the cooling device | |
| 59 | (0..max_state) | |
| 60 | max_state - RO file for maximum cooling state of the cooling device |