freebsd-dev/sys/powerpc/include/sr.h
Nathan Whitehorn ab73970649 Reduce KVA pressure on OEA64 systems running in bridge mode by mapping
UMA segments at their physical addresses instead of into KVA. This emulates
the direct mapping behavior of OEA32 in an ad-hoc way. To make this work
properly required sharing the entire kernel PMAP with Open Firmware, so
ofw_pmap is transformed into a stub on 64-bit CPUs.

Also implement some more tweaks to get more mileage out of our limited
amount of KVA, principally by extending KVA into segment 16 until the
beginning of the first OFW mapping.

Reported by:	linimon
2010-02-20 16:23:29 +00:00

58 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 KERNEL3_SR 15
#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_ */