LXR linux/arch/mips/include/asm/war.h

   1/*
   2 * This file is subject to the terms and conditions of the GNU General Public
   3 * License.  See the file "COPYING" in the main directory of this archive
   4 * for more details.
   5 *
   6 * Copyright (C) 2002, 2004, 2007 by Ralf Baechle
   7 * Copyright (C) 2007  Maciej W. Rozycki
   8 */
   9#ifndef _ASM_WAR_H
  10#define _ASM_WAR_H
  11
  12/*
  13 * Work around certain R4000 CPU errata (as implemented by GCC):
  14 *
  15 * - A double-word or a variable shift may give an incorrect result
  16 *   if executed immediately after starting an integer division:
  17 *   "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0",
  18 *   erratum #28
  19 *   "MIPS R4000MC Errata, Processor Revision 2.2 and 3.0", erratum
  20 *   #19
  21 *
  22 * - A double-word or a variable shift may give an incorrect result
  23 *   if executed while an integer multiplication is in progress:
  24 *   "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0",
  25 *   errata #16 & #28
  26 *
  27 * - An integer division may give an incorrect result if started in
  28 *   a delay slot of a taken branch or a jump:
  29 *   "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0",
  30 *   erratum #52
  31 */
  32#ifdef CONFIG_CPU_R4000_WORKAROUNDS
  33#define R4000_WAR 1
  34#else
  35#define R4000_WAR 0
  36#endif
  37
  38/*
  39 * Work around certain R4400 CPU errata (as implemented by GCC):
  40 *
  41 * - A double-word or a variable shift may give an incorrect result
  42 *   if executed immediately after starting an integer division:
  43 *   "MIPS R4400MC Errata, Processor Revision 1.0", erratum #10
  44 *   "MIPS R4400MC Errata, Processor Revision 2.0 & 3.0", erratum #4
  45 */
  46#ifdef CONFIG_CPU_R4400_WORKAROUNDS
  47#define R4400_WAR 1
  48#else
  49#define R4400_WAR 0
  50#endif
  51
  52/*
  53 * Work around the "daddi" and "daddiu" CPU errata:
  54 *
  55 * - The `daddi' instruction fails to trap on overflow.
  56 *   "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0",
  57 *   erratum #23
  58 *
  59 * - The `daddiu' instruction can produce an incorrect result.
  60 *   "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0",
  61 *   erratum #41
  62 *   "MIPS R4000MC Errata, Processor Revision 2.2 and 3.0", erratum
  63 *   #15
  64 *   "MIPS R4400PC/SC Errata, Processor Revision 1.0", erratum #7
  65 *   "MIPS R4400MC Errata, Processor Revision 1.0", erratum #5
  66 */
  67#ifdef CONFIG_CPU_DADDI_WORKAROUNDS
  68#define DADDI_WAR 1
  69#else
  70#define DADDI_WAR 0
  71#endif
  72
  73#endif /* _ASM_WAR_H */
  74