root/drivers/watchdog/nv_tco.h
/* SPDX-License-Identifier: GPL-2.0+ */
/*
 *      nv_tco: TCO timer driver for nVidia chipsets.
 *
 *      (c) Copyright 2005 Google Inc., All Rights Reserved.
 *
 *      Supported Chipsets:
 *              - MCP51/MCP55
 *
 *      (c) Copyright 2000 kernel concepts <nils@kernelconcepts.de>, All Rights
 *      Reserved.
 *                              https://www.kernelconcepts.de
 *
 *      Neither kernel concepts nor Nils Faerber admit liability nor provide
 *      warranty for any of this software. This material is provided
 *      "AS-IS" and at no charge.
 *
 *      (c) Copyright 2000      kernel concepts <nils@kernelconcepts.de>
 *                              developed for
 *                              Jentro AG, Haar/Munich (Germany)
 *
 *      TCO timer driver for NV chipsets
 *      based on softdog.c by Alan Cox <alan@redhat.com>
 */

/*
 * Some address definitions for the TCO
 */

#define TCO_RLD(base)   ((base) + 0x00) /* TCO Timer Reload and Current Value */
#define TCO_TMR(base)   ((base) + 0x01) /* TCO Timer Initial Value      */

#define TCO_STS(base)   ((base) + 0x04) /* TCO Status Register          */
/*
 * TCO Boot Status bit: set on TCO reset, reset by software or standby
 * power-good (survives reboots), unfortunately this bit is never
 * set.
 */
#  define TCO_STS_BOOT_STS      (1 << 9)
/*
 * first and 2nd timeout status bits, these also survive a warm boot,
 * and they work, so we use them.
 */
#  define TCO_STS_TCO_INT_STS   (1 << 1)
#  define TCO_STS_TCO2TO_STS    (1 << 10)
#  define TCO_STS_RESET         (TCO_STS_BOOT_STS | TCO_STS_TCO2TO_STS | \
                                 TCO_STS_TCO_INT_STS)

#define TCO_CNT(base)   ((base) + 0x08) /* TCO Control Register */
#  define TCO_CNT_TCOHALT       (1 << 12)

#define MCP51_SMBUS_SETUP_B 0xe8
#  define MCP51_SMBUS_SETUP_B_TCO_REBOOT (1 << 25)

/*
 * The SMI_EN register is at the base io address + 0x04,
 * while TCOBASE is + 0x40.
 */
#define MCP51_SMI_EN(base)      ((base) - 0x40 + 0x04)
#  define MCP51_SMI_EN_TCO      ((1 << 4) | (1 << 5))