diff options
| author | Maciej W. Rozycki <macro@linux-mips.org> | 2007-10-23 12:43:11 +0100 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2008-01-29 10:14:54 +0000 |
| commit | 20d60d9973c3b441902b0a3f4f6f7e7ade08f77d (patch) | |
| tree | 2dbadcb5600fcb486612ec30d972e6c29195ee1d /arch/mips/kernel/setup.c | |
| parent | 2b22c034d04d3632a339d14d5803c8f94e412608 (diff) | |
[MIPS] R4000/R4400 errata workarounds
This is the gereric part of R4000/R4400 errata workarounds. They include
compiler and assembler support as well as some source code modifications
to address the problems with some combinations of multiply/divide+shift
instructions as well as the daddi and daddiu instructions.
Changes included are as follows:
1. New Kconfig options to select workarounds by platforms as necessary.
2. Arch top-level Makefile to pass necessary options to the compiler; also
incompatible configurations are detected (-mno-sym32 unsupported as
horribly intrusive for little gain).
3. Bug detection updated and shuffled -- the multiply/divide+shift problem
is lethal enough that if not worked around it makes the kernel crash in
time_init() because of a division by zero; the daddiu erratum might
also trigger early potentially, though I have not observed it. On the
other hand the daddi detection code requires the exception subsystem to
have been initialised (and is there mainly for information).
4. r4k_daddiu_bug() added so that the existence of the erratum can be
queried by code at the run time as necessary; useful for generated code
like TLB fault and copy/clear page handlers.
5. __udelay() updated as it uses multiplication in inline assembly.
Note that -mdaddi requires modified toolchain (which has been maintained
by myself and available from my site for ~4years now -- versions covered
are GCC 2.95.4 - 4.1.2 and binutils from 2.13 onwards). The -mfix-r4000
and -mfix-r4400 have been standard for a while though.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel/setup.c')
| -rw-r--r-- | arch/mips/kernel/setup.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index f8a535afce39..7b4418dd5857 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -8,7 +8,7 @@ * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 01, 02, 03 Ralf Baechle * Copyright (C) 1996 Stoned Elipot * Copyright (C) 1999 Silicon Graphics, Inc. - * Copyright (C) 2000 2001, 2002 Maciej W. Rozycki + * Copyright (C) 2000, 2001, 2002, 2007 Maciej W. Rozycki */ #include <linux/init.h> #include <linux/ioport.h> @@ -24,6 +24,7 @@ #include <asm/addrspace.h> #include <asm/bootinfo.h> +#include <asm/bugs.h> #include <asm/cache.h> #include <asm/cpu.h> #include <asm/sections.h> @@ -561,6 +562,7 @@ void __init setup_arch(char **cmdline_p) } #endif cpu_report(); + check_bugs_early(); #if defined(CONFIG_VT) #if defined(CONFIG_VGA_CONSOLE) |