freebsd-skq/sys/powerpc/include/sr.h
grehan 1ae35df349 Increase kernel VA from 256Mb to 512Mb by shifting the segment used
for user copyinout down to 12, and keeping segments 13/14 for
kernel VA.

It would be nice to have more available, but segments lower than
this are reserved for either memory or 1:1 mapped device i/o,
and seg 15 is OpenFirmware ROM. Also, the effort to keep OpenFirmware
available for callbacks limits the use of VA-mapped segments.
Fortunately UMA_MD_SMALL_ALLOC takes away a lot of VM pressure.

Obtained from:  NetBSD
2004-03-02 06:49:21 +00:00

57 lines
2.2 KiB
C

/*
* Copyright (C) 2002 Benno Rice.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY Benno Rice ``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 TOOLS GMBH 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.
*
* $FreeBSD$
*/
#ifndef _MACHINE_SR_H_
#define _MACHINE_SR_H_
/*
* Bit definitions for segment registers.
*
* PowerPC Microprocessor Family: The Programming Environments for 32-bit
* Microprocessors, section 2.3.5
*/
#define SR_TYPE 0x80000000 /* Type selector */
#define SR_KS 0x40000000 /* Supervisor-state protection key */
#define SR_KP 0x20000000 /* User-state protection key */
#define SR_N 0x10000000 /* No-execute protection */
#define SR_VSID_MASK 0x00ffffff /* Virtual Segment ID mask */
/* Kernel segment register usage */
#define USER_SR 12
#define KERNEL_SR 13
#define KERNEL2_SR 14
#define KERNEL_VSIDBITS 0xfffff
#define KERNEL_SEGMENT (0xfffff0 + KERNEL_SR)
#define KERNEL2_SEGMENT (0xfffff0 + KERNEL2_SR)
#define EMPTY_SEGMENT 0xfffff0
#define USER_ADDR ((void *)(USER_SR << ADDR_SR_SHFT))
#define SEGMENT_LENGTH 0x10000000
#define SEGMENT_MASK 0xf0000000
#endif /* !_MACHINE_SR_H_ */