Messages in this thread | | | Date | Sun, 26 Feb 2023 23:09:40 +0100 | Subject | Re: [PATCH 2/2] MIPS: ebpf jit: Implement R4000 workarounds | From | Philippe Mathieu-Daudé <> |
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On 22/2/23 17:12, Jiaxun Yang wrote: > For R4000 erratas around multiplication and division instructions, > as our use of those instructions are always followed by mflo/mfhi > instructions, the only issue we need care is > > "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0" Errata 28: > "A double-word or a variable shift may give an incorrect result if > executed while an integer multiplication is in progress." > > We just emit a mfhi $0 to ensure the operation is completed after > every multiplication instruction accorading to workaround suggestion
Typo "according"
> in the document. > > Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> > --- > arch/mips/Kconfig | 4 +--- > arch/mips/net/bpf_jit_comp32.c | 4 ++++ > arch/mips/net/bpf_jit_comp64.c | 3 +++ > 3 files changed, 8 insertions(+), 3 deletions(-)
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
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