linux/arch/sparc64/lib/VISsave.S
David S. Miller ba6399334d [SPARC64]: Fix userland FPU state corruption.
We need to use stricter memory barriers around the block
load and store instructions we use to save and restore the
FPU register file.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-07 13:30:49 -07:00

145 lines
2.9 KiB
ArmAsm

/* $Id: VISsave.S,v 1.6 2002/02/09 19:49:30 davem Exp $
* VISsave.S: Code for saving FPU register state for
* VIS routines. One should not call this directly,
* but use macros provided in <asm/visasm.h>.
*
* Copyright (C) 1998 Jakub Jelinek (jj@ultra.linux.cz)
*/
#include <asm/asi.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/visasm.h>
#include <asm/thread_info.h>
.text
.globl VISenter, VISenterhalf
/* On entry: %o5=current FPRS value, %g7 is callers address */
/* May clobber %o5, %g1, %g2, %g3, %g7, %icc, %xcc */
/* Nothing special need be done here to handle pre-emption, this
* FPU save/restore mechanism is already preemption safe.
*/
.align 32
VISenter:
ldub [%g6 + TI_FPDEPTH], %g1
brnz,a,pn %g1, 1f
cmp %g1, 1
stb %g0, [%g6 + TI_FPSAVED]
stx %fsr, [%g6 + TI_XFSR]
9: jmpl %g7 + %g0, %g0
nop
1: bne,pn %icc, 2f
srl %g1, 1, %g1
vis1: ldub [%g6 + TI_FPSAVED], %g3
stx %fsr, [%g6 + TI_XFSR]
or %g3, %o5, %g3
stb %g3, [%g6 + TI_FPSAVED]
rd %gsr, %g3
clr %g1
ba,pt %xcc, 3f
stx %g3, [%g6 + TI_GSR]
2: add %g6, %g1, %g3
cmp %o5, FPRS_DU
be,pn %icc, 6f
sll %g1, 3, %g1
stb %o5, [%g3 + TI_FPSAVED]
rd %gsr, %g2
add %g6, %g1, %g3
stx %g2, [%g3 + TI_GSR]
add %g6, %g1, %g2
stx %fsr, [%g2 + TI_XFSR]
sll %g1, 5, %g1
3: andcc %o5, FPRS_DL|FPRS_DU, %g0
be,pn %icc, 9b
add %g6, TI_FPREGS, %g2
andcc %o5, FPRS_DL, %g0
be,pn %icc, 4f
add %g6, TI_FPREGS+0x40, %g3
membar #Sync
stda %f0, [%g2 + %g1] ASI_BLK_P
stda %f16, [%g3 + %g1] ASI_BLK_P
membar #Sync
andcc %o5, FPRS_DU, %g0
be,pn %icc, 5f
4: add %g1, 128, %g1
membar #Sync
stda %f32, [%g2 + %g1] ASI_BLK_P
stda %f48, [%g3 + %g1] ASI_BLK_P
5: membar #Sync
ba,pt %xcc, 80f
nop
.align 32
80: jmpl %g7 + %g0, %g0
nop
6: ldub [%g3 + TI_FPSAVED], %o5
or %o5, FPRS_DU, %o5
add %g6, TI_FPREGS+0x80, %g2
stb %o5, [%g3 + TI_FPSAVED]
sll %g1, 5, %g1
add %g6, TI_FPREGS+0xc0, %g3
wr %g0, FPRS_FEF, %fprs
membar #Sync
stda %f32, [%g2 + %g1] ASI_BLK_P
stda %f48, [%g3 + %g1] ASI_BLK_P
membar #Sync
ba,pt %xcc, 80f
nop
.align 32
80: jmpl %g7 + %g0, %g0
nop
.align 32
VISenterhalf:
ldub [%g6 + TI_FPDEPTH], %g1
brnz,a,pn %g1, 1f
cmp %g1, 1
stb %g0, [%g6 + TI_FPSAVED]
stx %fsr, [%g6 + TI_XFSR]
clr %o5
jmpl %g7 + %g0, %g0
wr %g0, FPRS_FEF, %fprs
1: bne,pn %icc, 2f
srl %g1, 1, %g1
ba,pt %xcc, vis1
sub %g7, 8, %g7
2: addcc %g6, %g1, %g3
sll %g1, 3, %g1
andn %o5, FPRS_DU, %g2
stb %g2, [%g3 + TI_FPSAVED]
rd %gsr, %g2
add %g6, %g1, %g3
stx %g2, [%g3 + TI_GSR]
add %g6, %g1, %g2
stx %fsr, [%g2 + TI_XFSR]
sll %g1, 5, %g1
3: andcc %o5, FPRS_DL, %g0
be,pn %icc, 4f
add %g6, TI_FPREGS, %g2
add %g6, TI_FPREGS+0x40, %g3
membar #Sync
stda %f0, [%g2 + %g1] ASI_BLK_P
stda %f16, [%g3 + %g1] ASI_BLK_P
membar #Sync
ba,pt %xcc, 4f
nop
.align 32
4: and %o5, FPRS_DU, %o5
jmpl %g7 + %g0, %g0
wr %o5, FPRS_FEF, %fprs