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| author |   Scott Wood <scottwood@freescale.com> | 2013-08-20 19:33:12 -0500 |
|---|---|---|
| committer | Scott Wood <scottwood@freescale.com> | 2013-08-20 19:33:12 -0500 |
| commit | beb2dc0a7a84be003ce54e98b95d65cc66e6e536 (patch) | |
| tree | a30c97effb8f723cccbc343306df4c7b6ab0047b /arch/powerpc/kernel/vdso32 | |
| parent | powerpc/fsl-booke: Work around erratum A-006958 (diff) | |
| download | linux-dev-beb2dc0a7a84be003ce54e98b95d65cc66e6e536.tar.xz linux-dev-beb2dc0a7a84be003ce54e98b95d65cc66e6e536.zip | |
powerpc: Convert some mftb/mftbu into mfspr
Some CPUs (such as e500v1/v2) don't implement mftb and will take a
trap. mfspr should work on everything that has a timebase, and is the
preferred instruction according to ISA v2.06.
Currently we get away with mftb on 85xx because the assembler converts
it to mfspr due to -Wa,-me500. However, that flag has other effects
that are undesireable for certain targets (e.g. lwsync is converted to
sync), and is hostile to multiplatform kernels. Thus we would like to
stop setting it for all e500-family builds.
mftb/mftbu instances which are in 85xx code or common code are
converted. Instances which will never run on 85xx are left alone.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Diffstat (limited to 'arch/powerpc/kernel/vdso32')
| -rw-r--r-- | arch/powerpc/kernel/vdso32/gettimeofday.S | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S index 27e2f623210b..6b1f2a6d5517 100644 --- a/arch/powerpc/kernel/vdso32/gettimeofday.S +++ b/arch/powerpc/kernel/vdso32/gettimeofday.S @@ -232,9 +232,9 @@ __do_get_tspec: lwz r6,(CFG_TB_ORIG_STAMP+4)(r9) /* Get a stable TB value */ -2: mftbu r3 - mftbl r4 - mftbu r0 +2: mfspr r3, SPRN_TBRU + mfspr r4, SPRN_TBRL + mfspr r0, SPRN_TBRU cmplw cr0,r3,r0 bne- 2b |