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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
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downloadlinux-stericsson-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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+November 23, 2004
+
+The following specification describes the SMSC LPC47B397-NC sensor chip
+(for which there is no public datasheet available). This document was
+provided by Craig Kelly (In-Store Broadcast Network) and edited/corrected
+by Mark M. Hoffman <mhoffman@lightlink.com>.
+
+* * * * *
+
+Methods for detecting the HP SIO and reading the thermal data on a dc7100.
+
+The thermal information on the dc7100 is contained in the SIO Hardware Monitor
+(HWM). The information is accessed through an index/data pair. The index/data
+pair is located at the HWM Base Address + 0 and the HWM Base Address + 1. The
+HWM Base address can be obtained from Logical Device 8, registers 0x60 (MSB)
+and 0x61 (LSB). Currently we are using 0x480 for the HWM Base Address and
+0x480 and 0x481 for the index/data pair.
+
+Reading temperature information.
+The temperature information is located in the following registers:
+Temp1 0x25 (Currently, this reflects the CPU temp on all systems).
+Temp2 0x26
+Temp3 0x27
+Temp4 0x80
+
+Programming Example
+The following is an example of how to read the HWM temperature registers:
+MOV DX,480H
+MOV AX,25H
+OUT DX,AL
+MOV DX,481H
+IN AL,DX
+
+AL contains the data in hex, the temperature in Celsius is the decimal
+equivalent.
+
+Ex: If AL contains 0x2A, the temperature is 42 degrees C.
+
+Reading tach information.
+The fan speed information is located in the following registers:
+ LSB MSB
+Tach1 0x28 0x29 (Currently, this reflects the CPU
+ fan speed on all systems).
+Tach2 0x2A 0x2B
+Tach3 0x2C 0x2D
+Tach4 0x2E 0x2F
+
+Important!!!
+Reading the tach LSB locks the tach MSB.
+The LSB Must be read first.
+
+How to convert the tach reading to RPM.
+The tach reading (TCount) is given by: (Tach MSB * 256) + (Tach LSB)
+The SIO counts the number of 90kHz (11.111us) pulses per revolution.
+RPM = 60/(TCount * 11.111us)
+
+Example:
+Reg 0x28 = 0x9B
+Reg 0x29 = 0x08
+
+TCount = 0x89B = 2203
+
+RPM = 60 / (2203 * 11.11111 E-6) = 2451 RPM
+
+Obtaining the SIO version.
+
+CONFIGURATION SEQUENCE
+To program the configuration registers, the following sequence must be followed:
+1. Enter Configuration Mode
+2. Configure the Configuration Registers
+3. Exit Configuration Mode.
+
+Enter Configuration Mode
+To place the chip into the Configuration State The config key (0x55) is written
+to the CONFIG PORT (0x2E).
+
+Configuration Mode
+In configuration mode, the INDEX PORT is located at the CONFIG PORT address and
+the DATA PORT is at INDEX PORT address + 1.
+
+The desired configuration registers are accessed in two steps:
+a. Write the index of the Logical Device Number Configuration Register
+ (i.e., 0x07) to the INDEX PORT and then write the number of the
+ desired logical device to the DATA PORT.
+
+b. Write the address of the desired configuration register within the
+ logical device to the INDEX PORT and then write or read the config-
+ uration register through the DATA PORT.
+
+Note: If accessing the Global Configuration Registers, step (a) is not required.
+
+Exit Configuration Mode
+To exit the Configuration State the write 0xAA to the CONFIG PORT (0x2E).
+The chip returns to the RUN State. (This is important).
+
+Programming Example
+The following is an example of how to read the SIO Device ID located at 0x20
+
+; ENTER CONFIGURATION MODE
+MOV DX,02EH
+MOV AX,055H
+OUT DX,AL
+; GLOBAL CONFIGURATION REGISTER
+MOV DX,02EH
+MOV AL,20H
+OUT DX,AL
+; READ THE DATA
+MOV DX,02FH
+IN AL,DX
+; EXIT CONFIGURATION MODE
+MOV DX,02EH
+MOV AX,0AAH
+OUT DX,AL
+
+The registers of interest for identifying the SIO on the dc7100 are Device ID
+(0x20) and Device Rev (0x21).
+
+The Device ID will read 0X6F
+The Device Rev currently reads 0x01
+
+Obtaining the HWM Base Address.
+The following is an example of how to read the HWM Base Address located in
+Logical Device 8.
+
+; ENTER CONFIGURATION MODE
+MOV DX,02EH
+MOV AX,055H
+OUT DX,AL
+; CONFIGURE REGISTER CRE0,
+; LOGICAL DEVICE 8
+MOV DX,02EH
+MOV AL,07H
+OUT DX,AL ;Point to LD# Config Reg
+MOV DX,02FH
+MOV AL, 08H
+OUT DX,AL;Point to Logical Device 8
+;
+MOV DX,02EH
+MOV AL,60H
+OUT DX,AL ; Point to HWM Base Addr MSB
+MOV DX,02FH
+IN AL,DX ; Get MSB of HWM Base Addr
+; EXIT CONFIGURATION MODE
+MOV DX,02EH
+MOV AX,0AAH
+OUT DX,AL