mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-24 05:04:00 +08:00
ede7fbdf52
Part 3: Move the drivers documentation, plus two general documentation files. Note that the patch "adds trailing whitespace", because it does move the files as-is, and some files happen to have trailing whitespace. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
170 lines
6.0 KiB
Plaintext
170 lines
6.0 KiB
Plaintext
Kernel driver fscher
|
|
====================
|
|
|
|
Supported chips:
|
|
* Fujitsu-Siemens Hermes chip
|
|
Prefix: 'fscher'
|
|
Addresses scanned: I2C 0x73
|
|
|
|
Authors:
|
|
Reinhard Nissl <rnissl@gmx.de> based on work
|
|
from Hermann Jung <hej@odn.de>,
|
|
Frodo Looijaard <frodol@dds.nl>,
|
|
Philip Edelbrock <phil@netroedge.com>
|
|
|
|
Description
|
|
-----------
|
|
|
|
This driver implements support for the Fujitsu-Siemens Hermes chip. It is
|
|
described in the 'Register Set Specification BMC Hermes based Systemboard'
|
|
from Fujitsu-Siemens.
|
|
|
|
The Hermes chip implements a hardware-based system management, e.g. for
|
|
controlling fan speed and core voltage. There is also a watchdog counter on
|
|
the chip which can trigger an alarm and even shut the system down.
|
|
|
|
The chip provides three temperature values (CPU, motherboard and
|
|
auxiliary), three voltage values (+12V, +5V and battery) and three fans
|
|
(power supply, CPU and auxiliary).
|
|
|
|
Temperatures are measured in degrees Celsius. The resolution is 1 degree.
|
|
|
|
Fan rotation speeds are reported in RPM (rotations per minute). The value
|
|
can be divided by a programmable divider (1, 2 or 4) which is stored on
|
|
the chip.
|
|
|
|
Voltage sensors (also known as "in" sensors) report their values in volts.
|
|
|
|
All values are reported as final values from the driver. There is no need
|
|
for further calculations.
|
|
|
|
|
|
Detailed description
|
|
--------------------
|
|
|
|
Below you'll find a single line description of all the bit values. With
|
|
this information, you're able to decode e. g. alarms, wdog, etc. To make
|
|
use of the watchdog, you'll need to set the watchdog time and enable the
|
|
watchdog. After that it is necessary to restart the watchdog time within
|
|
the specified period of time, or a system reset will occur.
|
|
|
|
* revision
|
|
READING & 0xff = 0x??: HERMES revision identification
|
|
|
|
* alarms
|
|
READING & 0x80 = 0x80: CPU throttling active
|
|
READING & 0x80 = 0x00: CPU running at full speed
|
|
|
|
READING & 0x10 = 0x10: software event (see control:1)
|
|
READING & 0x10 = 0x00: no software event
|
|
|
|
READING & 0x08 = 0x08: watchdog event (see wdog:2)
|
|
READING & 0x08 = 0x00: no watchdog event
|
|
|
|
READING & 0x02 = 0x02: thermal event (see temp*:1)
|
|
READING & 0x02 = 0x00: no thermal event
|
|
|
|
READING & 0x01 = 0x01: fan event (see fan*:1)
|
|
READING & 0x01 = 0x00: no fan event
|
|
|
|
READING & 0x13 ! 0x00: ALERT LED is flashing
|
|
|
|
* control
|
|
READING & 0x01 = 0x01: software event
|
|
READING & 0x01 = 0x00: no software event
|
|
|
|
WRITING & 0x01 = 0x01: set software event
|
|
WRITING & 0x01 = 0x00: clear software event
|
|
|
|
* watchdog_control
|
|
READING & 0x80 = 0x80: power off on watchdog event while thermal event
|
|
READING & 0x80 = 0x00: watchdog power off disabled (just system reset enabled)
|
|
|
|
READING & 0x40 = 0x40: watchdog timebase 60 seconds (see also wdog:1)
|
|
READING & 0x40 = 0x00: watchdog timebase 2 seconds
|
|
|
|
READING & 0x10 = 0x10: watchdog enabled
|
|
READING & 0x10 = 0x00: watchdog disabled
|
|
|
|
WRITING & 0x80 = 0x80: enable "power off on watchdog event while thermal event"
|
|
WRITING & 0x80 = 0x00: disable "power off on watchdog event while thermal event"
|
|
|
|
WRITING & 0x40 = 0x40: set watchdog timebase to 60 seconds
|
|
WRITING & 0x40 = 0x00: set watchdog timebase to 2 seconds
|
|
|
|
WRITING & 0x20 = 0x20: disable watchdog
|
|
|
|
WRITING & 0x10 = 0x10: enable watchdog / restart watchdog time
|
|
|
|
* watchdog_state
|
|
READING & 0x02 = 0x02: watchdog system reset occurred
|
|
READING & 0x02 = 0x00: no watchdog system reset occurred
|
|
|
|
WRITING & 0x02 = 0x02: clear watchdog event
|
|
|
|
* watchdog_preset
|
|
READING & 0xff = 0x??: configured watch dog time in units (see wdog:3 0x40)
|
|
|
|
WRITING & 0xff = 0x??: configure watch dog time in units
|
|
|
|
* in* (0: +5V, 1: +12V, 2: onboard 3V battery)
|
|
READING: actual voltage value
|
|
|
|
* temp*_status (1: CPU sensor, 2: onboard sensor, 3: auxiliary sensor)
|
|
READING & 0x02 = 0x02: thermal event (overtemperature)
|
|
READING & 0x02 = 0x00: no thermal event
|
|
|
|
READING & 0x01 = 0x01: sensor is working
|
|
READING & 0x01 = 0x00: sensor is faulty
|
|
|
|
WRITING & 0x02 = 0x02: clear thermal event
|
|
|
|
* temp*_input (1: CPU sensor, 2: onboard sensor, 3: auxiliary sensor)
|
|
READING: actual temperature value
|
|
|
|
* fan*_status (1: power supply fan, 2: CPU fan, 3: auxiliary fan)
|
|
READING & 0x04 = 0x04: fan event (fan fault)
|
|
READING & 0x04 = 0x00: no fan event
|
|
|
|
WRITING & 0x04 = 0x04: clear fan event
|
|
|
|
* fan*_div (1: power supply fan, 2: CPU fan, 3: auxiliary fan)
|
|
Divisors 2,4 and 8 are supported, both for reading and writing
|
|
|
|
* fan*_pwm (1: power supply fan, 2: CPU fan, 3: auxiliary fan)
|
|
READING & 0xff = 0x00: fan may be switched off
|
|
READING & 0xff = 0x01: fan must run at least at minimum speed (supply: 6V)
|
|
READING & 0xff = 0xff: fan must run at maximum speed (supply: 12V)
|
|
READING & 0xff = 0x??: fan must run at least at given speed (supply: 6V..12V)
|
|
|
|
WRITING & 0xff = 0x00: fan may be switched off
|
|
WRITING & 0xff = 0x01: fan must run at least at minimum speed (supply: 6V)
|
|
WRITING & 0xff = 0xff: fan must run at maximum speed (supply: 12V)
|
|
WRITING & 0xff = 0x??: fan must run at least at given speed (supply: 6V..12V)
|
|
|
|
* fan*_input (1: power supply fan, 2: CPU fan, 3: auxiliary fan)
|
|
READING: actual RPM value
|
|
|
|
|
|
Limitations
|
|
-----------
|
|
|
|
* Measuring fan speed
|
|
It seems that the chip counts "ripples" (typical fans produce 2 ripples per
|
|
rotation while VERAX fans produce 18) in a 9-bit register. This register is
|
|
read out every second, then the ripple prescaler (2, 4 or 8) is applied and
|
|
the result is stored in the 8 bit output register. Due to the limitation of
|
|
the counting register to 9 bits, it is impossible to measure a VERAX fan
|
|
properly (even with a prescaler of 8). At its maximum speed of 3500 RPM the
|
|
fan produces 1080 ripples per second which causes the counting register to
|
|
overflow twice, leading to only 186 RPM.
|
|
|
|
* Measuring input voltages
|
|
in2 ("battery") reports the voltage of the onboard lithium battery and not
|
|
+3.3V from the power supply.
|
|
|
|
* Undocumented features
|
|
Fujitsu-Siemens Computers has not documented all features of the chip so
|
|
far. Their software, System Guard, shows that there are a still some
|
|
features which cannot be controlled by this implementation.
|