tjh.dev
Linux kernel mirror (for testing)
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kernel
os
linux
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