xref: /openbmc/linux/drivers/watchdog/nv_tco.h (revision 827634ad)
1 /*
2  *	nv_tco:	TCO timer driver for nVidia chipsets.
3  *
4  *	(c) Copyright 2005 Google Inc., All Rights Reserved.
5  *
6  *	Supported Chipsets:
7  *		- MCP51/MCP55
8  *
9  *	(c) Copyright 2000 kernel concepts <nils@kernelconcepts.de>, All Rights
10  *	Reserved.
11  *				http://www.kernelconcepts.de
12  *
13  *	This program is free software; you can redistribute it and/or
14  *	modify it under the terms of the GNU General Public License
15  *	as published by the Free Software Foundation; either version
16  *	2 of the License, or (at your option) any later version.
17  *
18  *	Neither kernel concepts nor Nils Faerber admit liability nor provide
19  *	warranty for any of this software. This material is provided
20  *	"AS-IS" and at no charge.
21  *
22  *	(c) Copyright 2000	kernel concepts <nils@kernelconcepts.de>
23  *				developed for
24  *                              Jentro AG, Haar/Munich (Germany)
25  *
26  *	TCO timer driver for NV chipsets
27  *	based on softdog.c by Alan Cox <alan@redhat.com>
28  */
29 
30 /*
31  * Some address definitions for the TCO
32  */
33 
34 #define TCO_RLD(base)	((base) + 0x00)	/* TCO Timer Reload and Current Value */
35 #define TCO_TMR(base)	((base) + 0x01)	/* TCO Timer Initial Value	*/
36 
37 #define TCO_STS(base)	((base) + 0x04)	/* TCO Status Register		*/
38 /*
39  * TCO Boot Status bit: set on TCO reset, reset by software or standby
40  * power-good (survives reboots), unfortunately this bit is never
41  * set.
42  */
43 #  define TCO_STS_BOOT_STS	(1 << 9)
44 /*
45  * first and 2nd timeout status bits, these also survive a warm boot,
46  * and they work, so we use them.
47  */
48 #  define TCO_STS_TCO_INT_STS	(1 << 1)
49 #  define TCO_STS_TCO2TO_STS	(1 << 10)
50 #  define TCO_STS_RESET		(TCO_STS_BOOT_STS | TCO_STS_TCO2TO_STS | \
51 				 TCO_STS_TCO_INT_STS)
52 
53 #define TCO_CNT(base)	((base) + 0x08)	/* TCO Control Register	*/
54 #  define TCO_CNT_TCOHALT	(1 << 12)
55 
56 #define MCP51_SMBUS_SETUP_B 0xe8
57 #  define MCP51_SMBUS_SETUP_B_TCO_REBOOT (1 << 25)
58 
59 /*
60  * The SMI_EN register is at the base io address + 0x04,
61  * while TCOBASE is + 0x40.
62  */
63 #define MCP51_SMI_EN(base)	((base) - 0x40 + 0x04)
64 #  define MCP51_SMI_EN_TCO	((1 << 4) | (1 << 5))
65