diff options
| author | Akira Takeuchi <takeuchi.akr@jp.panasonic.com> | 2010-10-27 17:28:52 +0100 |
|---|---|---|
| committer | David Howells <dhowells@redhat.com> | 2010-10-27 17:28:52 +0100 |
| commit | 278d91c4609d55202c1e63d5fc5f01466cc7bbab (patch) | |
| tree | 8b0c863837508959430c1741e2e5a2d37d2890d4 /arch/mn10300/kernel/fpu-nofpu-low.S | |
| parent | 965ea4bbb9ae926358273368144ba838c561bc38 (diff) | |
MN10300: Make the FPU operate in non-lazy mode under SMP
Make the FPU operate in non-lazy mode under SMP so that when the process that
is currently using the FPU migrates to a different CPU, we don't have to ping
its previous CPU to flush the FPU context.
Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'arch/mn10300/kernel/fpu-nofpu-low.S')
| -rw-r--r-- | arch/mn10300/kernel/fpu-nofpu-low.S | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/arch/mn10300/kernel/fpu-nofpu-low.S b/arch/mn10300/kernel/fpu-nofpu-low.S new file mode 100644 index 000000000000..7ea087a549f4 --- /dev/null +++ b/arch/mn10300/kernel/fpu-nofpu-low.S @@ -0,0 +1,39 @@ +/* MN10300 Low level FPU management operations + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ +#include <linux/linkage.h> +#include <asm/cpu-regs.h> +#include <asm/smp.h> +#include <asm/thread_info.h> +#include <asm/asm-offsets.h> +#include <asm/frame.inc> + +############################################################################### +# +# void fpu_disabled(void) +# - handle an exception due to the FPU being disabled +# when CONFIG_FPU is disabled +# +############################################################################### + .type fpu_disabled,@function + .globl fpu_disabled +fpu_disabled: + add -4,sp + SAVE_ALL + mov -1,d0 + mov d0,(REG_ORIG_D0,fp) + + and ~EPSW_NMID,epsw + + mov fp,d0 + call unexpected_fpu_exception[],0 + jmp ret_from_exception + + .size fpu_disabled,.-fpu_disabled |