freebsd-skq/sys/sparc64/include/wstate.h
marius 86c825f191 - The firmware of Sun Fire V1280 has a misfeature of setting %wstate to
7 which corresponds to WSTATE_KMIX in OpenSolaris whenever calling into
  it which totally screws us even when restoring %wstate afterwards as
  spill/fill traps can happen while in OFW. The rather hackish OpenBSD
  approach of just setting the equivalent of WSTATE_KERNEL to 7 also is
  no option as we treat %wstate as a bit field. So in order to deal with
  this problem actually implement spill/fill handlers for %wstate 7 which
  just act as the WSTATE_KERNEL ones except of theoretically also handling
  32-bit, turn off interrupts completely so we don't even take IPIs while
  in OFW which should ensure we only take spill/fill traps at most and
  restore %wstate after calling into OFW once we have taken over the trap
  table. While at it, actually set WSTATE_{,PROM}_KMIX before calling into
  OFW just like OpenSolaris does, which should at least help testing this
  change on non-V1280.
- Remove comments referring to the %wstate usage in BSD/OS.
- Remove the no longer used RSF_ALIGN_RETRY macro.
- Correct some trap table addresses in comments.
- Ensure %wstate is set to WSTATE_KERNEL when taking over the trap table.
- Ensure PSTATE_AM is off when entering or exiting to OFW as well as that
  interrupts are also completely off when exiting to OFW as the firmware
  trap table shouldn't be used to handle our interrupts.
2010-03-21 13:09:54 +00:00

67 lines
2.8 KiB
C

/*-
* Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Berkeley Software Design Inc's name may not be used to endorse or
* promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: BSDI: wstate.h,v 1.4 1997/09/18 13:05:51 torek Exp
* $FreeBSD$
*/
#ifndef _MACHINE_WSTATE_H_
#define _MACHINE_WSTATE_H_
/*
* Window state register bits
*
* There really are no bits per se, just the two fields WSTATE.NORMAL
* and WSTATE.OTHER. The rest is up to software.
*
* We use WSTATE_NORMAL to represent user mode or kernel mode saves
* (whichever is currently in effect) and WSTATE_OTHER to represent
* user mode saves (only).
*
* Note that locore.s assumes this same bit layout (since the translation
* from "bits" to "{spill,fill}_N_{normal,other}" is done in hardware).
*/
#define WSTATE_NORMAL_MASK 1 /* wstate normal minus transition */
#define WSTATE_OTHER_SHIFT 3 /* for wstate other / user */
#define WSTATE_OTHER_MASK /* wstate other minus nested */ \
(WSTATE_NORMAL_MASK << WSTATE_OTHER_SHIFT)
#define WSTATE_KERNEL 0 /* normal kernel wstate */
#define WSTATE_USER_64 0 /* normal 64bit user wstate */
#define WSTATE_USER_32 1 /* normal 32bit user wstate */
#define WSTATE_TRANSITION 2 /* if set, force user window */
#define WSTATE_NESTED /* if set, spill must not fault */ \
(WSTATE_TRANSITION << WSTATE_OTHER_SHIFT)
/* Values used by the PROM and (Open)Solaris */
#define WSTATE_PROM_KMIX 7
#define WSTATE_PROM_MASK 7
#endif /* !_MACHINE_WSTATE_H_ */