diff options
| author | David Howells <dhowells@redhat.com> | 2008-04-10 16:10:55 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-04-10 13:41:29 -0700 |
| commit | e31c243f984628d02f045dc4b622f1e2827860dc (patch) | |
| tree | cd2ac2f33c7da86b515087260d93179b31fd1671 /arch/frv/kernel/entry.S | |
| parent | 0c93d8e4d342b1b5cda1037f2527fcf443c80fbc (diff) | |
FRV: Add support for emulation of userspace atomic ops [try #2]
Use traps 120-126 to emulate atomic cmpxchg32, xchg32, and XOR-, OR-, AND-, SUB-
and ADD-to-memory operations for userspace.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/frv/kernel/entry.S')
| -rw-r--r-- | arch/frv/kernel/entry.S | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/frv/kernel/entry.S b/arch/frv/kernel/entry.S index f36d7f4a7c25..b8a4b94779b1 100644 --- a/arch/frv/kernel/entry.S +++ b/arch/frv/kernel/entry.S @@ -656,6 +656,26 @@ __entry_debug_exception: ############################################################################### # +# handle atomic operation emulation for userspace +# +############################################################################### + .globl __entry_atomic_op +__entry_atomic_op: + LEDS 0x6012 + sethi.p %hi(atomic_operation),gr5 + setlo %lo(atomic_operation),gr5 + movsg esfr1,gr8 + movsg epcr0,gr9 + movsg esr0,gr10 + + # now that we've accessed the exception regs, we can enable exceptions + movsg psr,gr4 + ori gr4,#PSR_ET,gr4 + movgs gr4,psr + jmpl @(gr5,gr0) ; call atomic_operation(esfr1,epcr0,esr0) + +############################################################################### +# # handle media exception # ############################################################################### |