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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:03 EST.

1	Kernel driver smsc47b397
2	========================
3	
4	Supported chips:
5	  * SMSC LPC47B397-NC
6	  * SMSC SCH5307-NS
7	  * SMSC SCH5317
8	    Prefix: 'smsc47b397'
9	    Addresses scanned: none, address read from Super I/O config space
10	    Datasheet: In this file
11	
12	Authors: Mark M. Hoffman <mhoffman@lightlink.com>
13	         Utilitek Systems, Inc.
14	
15	November 23, 2004
16	
17	The following specification describes the SMSC LPC47B397-NC[1] sensor chip
18	(for which there is no public datasheet available). This document was
19	provided by Craig Kelly (In-Store Broadcast Network) and edited/corrected
20	by Mark M. Hoffman <mhoffman@lightlink.com>.
21	
22	[1] And SMSC SCH5307-NS and SCH5317, which have different device IDs but are
23	otherwise compatible.
24	
25	* * * * *
26	
27	Methods for detecting the HP SIO and reading the thermal data on a dc7100.
28	
29	The thermal information on the dc7100 is contained in the SIO Hardware Monitor
30	(HWM). The information is accessed through an index/data pair. The index/data
31	pair is located at the HWM Base Address + 0 and the HWM Base Address + 1. The
32	HWM Base address can be obtained from Logical Device 8, registers 0x60 (MSB)
33	and 0x61 (LSB). Currently we are using 0x480 for the HWM Base Address and
34	0x480 and 0x481 for the index/data pair.
35	
36	Reading temperature information.
37	The temperature information is located in the following registers:
38	Temp1		0x25	(Currently, this reflects the CPU temp on all systems).
39	Temp2		0x26
40	Temp3		0x27
41	Temp4		0x80
42	
43	Programming Example
44	The following is an example of how to read the HWM temperature registers:
45	MOV	DX,480H
46	MOV	AX,25H
47	OUT	DX,AL
48	MOV	DX,481H
49	IN	AL,DX
50	
51	AL contains the data in hex, the temperature in Celsius is the decimal
52	equivalent.
53	
54	Ex: If AL contains 0x2A, the temperature is 42 degrees C.
55	
56	Reading tach information.
57	The fan speed information is located in the following registers:
58			LSB	MSB
59	Tach1		0x28	0x29	(Currently, this reflects the CPU
60					fan speed on all systems).
61	Tach2		0x2A	0x2B
62	Tach3		0x2C	0x2D
63	Tach4		0x2E	0x2F
64	
65	Important!!!
66	Reading the tach LSB locks the tach MSB.
67	The LSB Must be read first.
68	
69	How to convert the tach reading to RPM.
70	The tach reading (TCount) is given by: (Tach MSB * 256) + (Tach LSB)
71	The SIO counts the number of 90kHz (11.111us) pulses per revolution.
72	RPM = 60/(TCount * 11.111us)
73	
74	Example:
75	Reg 0x28 = 0x9B
76	Reg 0x29 = 0x08
77	
78	TCount = 0x89B = 2203
79	
80	RPM = 60 / (2203 * 11.11111 E-6) = 2451 RPM
81	
82	Obtaining the SIO version.
83	
84	CONFIGURATION SEQUENCE
85	To program the configuration registers, the following sequence must be followed:
86	1. Enter Configuration Mode
87	2. Configure the Configuration Registers
88	3. Exit Configuration Mode.
89	
90	Enter Configuration Mode
91	To place the chip into the Configuration State The config key (0x55) is written
92	to the CONFIG PORT (0x2E).
93	
94	Configuration Mode
95	In configuration mode, the INDEX PORT is located at the CONFIG PORT address and
96	the DATA PORT is at INDEX PORT address + 1.
97	
98	The desired configuration registers are accessed in two steps:
99	a.	Write the index of the Logical Device Number Configuration Register
100		(i.e., 0x07) to the INDEX PORT and then write the number of the
101		desired logical device to the DATA PORT.
102	
103	b.	Write the address of the desired configuration register within the
104		logical device to the INDEX PORT and then write or read the config-
105		uration register through the DATA PORT.
106	
107	Note: If accessing the Global Configuration Registers, step (a) is not required.
108	
109	Exit Configuration Mode
110	To exit the Configuration State the write 0xAA to the CONFIG PORT (0x2E).
111	The chip returns to the RUN State.  (This is important).
112	
113	Programming Example
114	The following is an example of how to read the SIO Device ID located at 0x20
115	
116	; ENTER CONFIGURATION MODE
117	MOV	DX,02EH
118	MOV	AX,055H
119	OUT	DX,AL
120	; GLOBAL CONFIGURATION  REGISTER
121	MOV	DX,02EH
122	MOV	AL,20H
123	OUT	DX,AL
124	; READ THE DATA
125	MOV	DX,02FH
126	IN	AL,DX
127	; EXIT CONFIGURATION MODE
128	MOV	DX,02EH
129	MOV	AX,0AAH
130	OUT	DX,AL
131	
132	The registers of interest for identifying the SIO on the dc7100 are Device ID
133	(0x20) and Device Rev  (0x21).
134	
135	The Device ID will read 0x6F (0x81 for SCH5307-NS, and 0x85 for SCH5317)
136	The Device Rev currently reads 0x01
137	
138	Obtaining the HWM Base Address.
139	The following is an example of how to read the HWM Base Address located in
140	Logical Device 8.
141	
142	; ENTER CONFIGURATION MODE
143	MOV	DX,02EH
144	MOV	AX,055H
145	OUT	DX,AL
146	; CONFIGURE REGISTER CRE0,
147	; LOGICAL DEVICE 8
148	MOV	DX,02EH
149	MOV	AL,07H
150	OUT	DX,AL ;Point to LD# Config Reg
151	MOV	DX,02FH
152	MOV	AL, 08H
153	OUT	DX,AL;Point to Logical Device 8
154	;
155	MOV	DX,02EH
156	MOV	AL,60H
157	OUT	DX,AL	; Point to HWM Base Addr MSB
158	MOV	DX,02FH
159	IN	AL,DX	; Get MSB of HWM Base Addr
160	; EXIT CONFIGURATION MODE
161	MOV	DX,02EH
162	MOV	AX,0AAH
163	OUT	DX,AL
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