MIPS: Fix MSA assembly with big thread offsets
When lockdep is enabled on a 64-bit kernel the FPR offset into the thread structure exceeds the maximum range of the MSA ld.d/st.d instructions. For example THREAD_FPR31 = 4644 (instead of 2448), while the signed immediate field is only 10 bits with an implicit multiply by 8, giving a maximum offset of 511*8 = 4088. This isn't a problem when the toolchain doesn't support MSA as the ld_*/st_* macros perform the addition separately into $1 with [d]addui which has a 16bit signed immediate field. Fix the case where the toolchain does support MSA by doing a single addition of THREAD_FPR0 into $1 with [d]addui, and doing the ld_*/st_* relative to that. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13064/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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