linux/include/asm-xtensa/regs.h
Chris Zankel c658eac628 [XTENSA] Add support for configurable registers and coprocessors
The Xtensa architecture allows to define custom instructions and
registers. Registers that are bound to a coprocessor are only
accessible if the corresponding enable bit is set, which allows
to implement a 'lazy' context switch mechanism. Other registers
needs to be saved and restore at the time of the context switch
or during interrupt handling.

This patch adds support for these additional states:

- save and restore registers that are used by the compiler upon
  interrupt entry and exit.
- context switch additional registers unbound to any coprocessor
- 'lazy' context switch of registers bound to a coprocessor
- ptrace interface to provide access to additional registers
- update configuration files in include/asm-xtensa/variant-fsf

Signed-off-by: Chris Zankel <chris@zankel.net>
2008-02-13 17:41:43 -08:00

145 lines
4.2 KiB
C

/*
* Copyright (c) 2006 Tensilica, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2.1 of the GNU Lesser General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* Further, this software is distributed without any warranty that it is
* free of the rightful claim of any third person regarding infringement
* or the like. Any license provided herein, whether implied or
* otherwise, applies only to this software file. Patent licenses, if
* any, provided herein do not apply to combinations of this program with
* other software, or any other product whatsoever.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, write the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307,
* USA.
*/
#ifndef _XTENSA_REGS_H
#define _XTENSA_REGS_H
/* Special registers. */
#define LBEG 0
#define LEND 1
#define LCOUNT 2
#define SAR 3
#define BR 4
#define SCOMPARE1 12
#define ACCHI 16
#define ACCLO 17
#define MR 32
#define WINDOWBASE 72
#define WINDOWSTART 73
#define PTEVADDR 83
#define RASID 90
#define ITLBCFG 91
#define DTLBCFG 92
#define IBREAKENABLE 96
#define DDR 104
#define IBREAKA 128
#define DBREAKA 144
#define DBREAKC 160
#define EPC 176
#define EPC_1 177
#define DEPC 192
#define EPS 192
#define EPS_1 193
#define EXCSAVE 208
#define EXCSAVE_1 209
#define INTERRUPT 226
#define INTENABLE 228
#define PS 230
#define THREADPTR 231
#define EXCCAUSE 232
#define DEBUGCAUSE 233
#define CCOUNT 234
#define PRID 235
#define ICOUNT 236
#define ICOUNTLEVEL 237
#define EXCVADDR 238
#define CCOMPARE 240
#define MISC 244
/* Special names for read-only and write-only interrupt registers. */
#define INTREAD 226
#define INTSET 226
#define INTCLEAR 227
/* EXCCAUSE register fields */
#define EXCCAUSE_EXCCAUSE_SHIFT 0
#define EXCCAUSE_EXCCAUSE_MASK 0x3F
#define EXCCAUSE_ILLEGAL_INSTRUCTION 0
#define EXCCAUSE_SYSTEM_CALL 1
#define EXCCAUSE_INSTRUCTION_FETCH_ERROR 2
#define EXCCAUSE_LOAD_STORE_ERROR 3
#define EXCCAUSE_LEVEL1_INTERRUPT 4
#define EXCCAUSE_ALLOCA 5
#define EXCCAUSE_INTEGER_DIVIDE_BY_ZERO 6
#define EXCCAUSE_SPECULATION 7
#define EXCCAUSE_PRIVILEGED 8
#define EXCCAUSE_UNALIGNED 9
#define EXCCAUSE_ITLB_MISS 16
#define EXCCAUSE_ITLB_MULTIHIT 17
#define EXCCAUSE_ITLB_PRIVILEGE 18
#define EXCCAUSE_ITLB_SIZE_RESTRICTION 19
#define EXCCAUSE_FETCH_CACHE_ATTRIBUTE 20
#define EXCCAUSE_DTLB_MISS 24
#define EXCCAUSE_DTLB_MULTIHIT 25
#define EXCCAUSE_DTLB_PRIVILEGE 26
#define EXCCAUSE_DTLB_SIZE_RESTRICTION 27
#define EXCCAUSE_LOAD_CACHE_ATTRIBUTE 28
#define EXCCAUSE_STORE_CACHE_ATTRIBUTE 29
#define EXCCAUSE_COPROCESSOR0_DISABLED 32
#define EXCCAUSE_COPROCESSOR1_DISABLED 33
#define EXCCAUSE_COPROCESSOR2_DISABLED 34
#define EXCCAUSE_COPROCESSOR3_DISABLED 35
#define EXCCAUSE_COPROCESSOR4_DISABLED 36
#define EXCCAUSE_COPROCESSOR5_DISABLED 37
#define EXCCAUSE_COPROCESSOR6_DISABLED 38
#define EXCCAUSE_COPROCESSOR7_DISABLED 39
/* PS register fields. */
#define PS_WOE_BIT 18
#define PS_CALLINC_SHIFT 16
#define PS_CALLINC_MASK 0x00030000
#define PS_OWB_SHIFT 8
#define PS_OWB_MASK 0x00000F00
#define PS_RING_SHIFT 6
#define PS_RING_MASK 0x000000C0
#define PS_UM_BIT 5
#define PS_EXCM_BIT 4
#define PS_INTLEVEL_SHIFT 0
#define PS_INTLEVEL_MASK 0x0000000F
/* DBREAKCn register fields. */
#define DBREAKC_MASK_BIT 0
#define DBREAKC_MASK_MASK 0x0000003F
#define DBREAKC_LOAD_BIT 30
#define DBREAKC_LOAD_MASK 0x40000000
#define DBREAKC_STOR_BIT 31
#define DBREAKC_STOR_MASK 0x80000000
/* DEBUGCAUSE register fields. */
#define DEBUGCAUSE_DEBUGINT_BIT 5 /* External debug interrupt */
#define DEBUGCAUSE_BREAKN_BIT 4 /* BREAK.N instruction */
#define DEBUGCAUSE_BREAK_BIT 3 /* BREAK instruction */
#define DEBUGCAUSE_DBREAK_BIT 2 /* DBREAK match */
#define DEBUGCAUSE_IBREAK_BIT 1 /* IBREAK match */
#define DEBUGCAUSE_ICOUNT_BIT 0 /* ICOUNT would incr. to zero */
#endif /* _XTENSA_SPECREG_H */