cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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smsc47b397.rst (5302B)


      1Kernel driver smsc47b397
      2========================
      3
      4Supported chips:
      5
      6  * SMSC LPC47B397-NC
      7
      8  * SMSC SCH5307-NS
      9
     10  * SMSC SCH5317
     11
     12    Prefix: 'smsc47b397'
     13
     14    Addresses scanned: none, address read from Super I/O config space
     15
     16    Datasheet: In this file
     17
     18Authors:
     19
     20       - Mark M. Hoffman <mhoffman@lightlink.com>
     21       - Utilitek Systems, Inc.
     22
     23November 23, 2004
     24
     25The following specification describes the SMSC LPC47B397-NC [1]_ sensor chip
     26(for which there is no public datasheet available). This document was
     27provided by Craig Kelly (In-Store Broadcast Network) and edited/corrected
     28by Mark M. Hoffman <mhoffman@lightlink.com>.
     29
     30.. [1] And SMSC SCH5307-NS and SCH5317, which have different device IDs but are
     31       otherwise compatible.
     32
     33-------------------------------------------------------------------------
     34
     35Methods for detecting the HP SIO and reading the thermal data on a dc7100
     36-------------------------------------------------------------------------
     37
     38The thermal information on the dc7100 is contained in the SIO Hardware Monitor
     39(HWM). The information is accessed through an index/data pair. The index/data
     40pair is located at the HWM Base Address + 0 and the HWM Base Address + 1. The
     41HWM Base address can be obtained from Logical Device 8, registers 0x60 (MSB)
     42and 0x61 (LSB). Currently we are using 0x480 for the HWM Base Address and
     430x480 and 0x481 for the index/data pair.
     44
     45Reading temperature information.
     46The temperature information is located in the following registers:
     47
     48=============== ======= =======================================================
     49Temp1		0x25	(Currently, this reflects the CPU temp on all systems).
     50Temp2		0x26
     51Temp3		0x27
     52Temp4		0x80
     53=============== ======= =======================================================
     54
     55Programming Example
     56The following is an example of how to read the HWM temperature registers::
     57
     58	MOV	DX,480H
     59	MOV	AX,25H
     60	OUT	DX,AL
     61	MOV	DX,481H
     62	IN	AL,DX
     63
     64AL contains the data in hex, the temperature in Celsius is the decimal
     65equivalent.
     66
     67Ex: If AL contains 0x2A, the temperature is 42 degrees C.
     68
     69Reading tach information.
     70The fan speed information is located in the following registers:
     71
     72=============== ======= ======= =================================
     73		LSB	MSB
     74Tach1		0x28	0x29	(Currently, this reflects the CPU
     75				fan speed on all systems).
     76Tach2		0x2A	0x2B
     77Tach3		0x2C	0x2D
     78Tach4		0x2E	0x2F
     79=============== ======= ======= =================================
     80
     81.. Important::
     82
     83	Reading the tach LSB locks the tach MSB.
     84	The LSB Must be read first.
     85
     86How to convert the tach reading to RPM
     87--------------------------------------
     88
     89The tach reading (TCount) is given by: (Tach MSB * 256) + (Tach LSB)
     90The SIO counts the number of 90kHz (11.111us) pulses per revolution.
     91RPM = 60/(TCount * 11.111us)
     92
     93Example::
     94
     95	Reg 0x28 = 0x9B
     96	Reg 0x29 = 0x08
     97
     98TCount = 0x89B = 2203
     99
    100RPM = 60 / (2203 * 11.11111 E-6) = 2451 RPM
    101
    102Obtaining the SIO version.
    103
    104Configuration Sequence
    105----------------------
    106
    107To program the configuration registers, the following sequence must be followed:
    1081. Enter Configuration Mode
    1092. Configure the Configuration Registers
    1103. Exit Configuration Mode.
    111
    112Enter Configuration Mode
    113^^^^^^^^^^^^^^^^^^^^^^^^
    114
    115To place the chip into the Configuration State The config key (0x55) is written
    116to the CONFIG PORT (0x2E).
    117
    118Configuration Mode
    119^^^^^^^^^^^^^^^^^^
    120
    121In configuration mode, the INDEX PORT is located at the CONFIG PORT address and
    122the DATA PORT is at INDEX PORT address + 1.
    123
    124The desired configuration registers are accessed in two steps:
    125
    126a.	Write the index of the Logical Device Number Configuration Register
    127	(i.e., 0x07) to the INDEX PORT and then write the number of the
    128	desired logical device to the DATA PORT.
    129
    130b.	Write the address of the desired configuration register within the
    131	logical device to the INDEX PORT and then write or read the config-
    132	uration register through the DATA PORT.
    133
    134Note:
    135	If accessing the Global Configuration Registers, step (a) is not required.
    136
    137Exit Configuration Mode
    138^^^^^^^^^^^^^^^^^^^^^^^
    139
    140To exit the Configuration State the write 0xAA to the CONFIG PORT (0x2E).
    141The chip returns to the RUN State.  (This is important).
    142
    143Programming Example
    144^^^^^^^^^^^^^^^^^^^
    145
    146The following is an example of how to read the SIO Device ID located at 0x20:
    147
    148	; ENTER CONFIGURATION MODE
    149	MOV	DX,02EH
    150	MOV	AX,055H
    151	OUT	DX,AL
    152	; GLOBAL CONFIGURATION  REGISTER
    153	MOV	DX,02EH
    154	MOV	AL,20H
    155	OUT	DX,AL
    156	; READ THE DATA
    157	MOV	DX,02FH
    158	IN	AL,DX
    159	; EXIT CONFIGURATION MODE
    160	MOV	DX,02EH
    161	MOV	AX,0AAH
    162	OUT	DX,AL
    163
    164The registers of interest for identifying the SIO on the dc7100 are Device ID
    165(0x20) and Device Rev  (0x21).
    166
    167The Device ID will read 0x6F (0x81 for SCH5307-NS, and 0x85 for SCH5317)
    168The Device Rev currently reads 0x01
    169
    170Obtaining the HWM Base Address
    171------------------------------
    172
    173The following is an example of how to read the HWM Base Address located in
    174Logical Device 8::
    175
    176	; ENTER CONFIGURATION MODE
    177	MOV	DX,02EH
    178	MOV	AX,055H
    179	OUT	DX,AL
    180	; CONFIGURE REGISTER CRE0,
    181	; LOGICAL DEVICE 8
    182	MOV	DX,02EH
    183	MOV	AL,07H
    184	OUT	DX,AL ;Point to LD# Config Reg
    185	MOV	DX,02FH
    186	MOV	AL, 08H
    187	OUT	DX,AL;Point to Logical Device 8
    188	;
    189	MOV	DX,02EH
    190	MOV	AL,60H
    191	OUT	DX,AL	; Point to HWM Base Addr MSB
    192	MOV	DX,02FH
    193	IN	AL,DX	; Get MSB of HWM Base Addr
    194	; EXIT CONFIGURATION MODE
    195	MOV	DX,02EH
    196	MOV	AX,0AAH
    197	OUT	DX,AL