From 1db1af84d6df99a8e5d6ddea8c7b5c1327c9a620 Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Mon, 27 Jan 2014 15:23:11 +0000 Subject: MIPS: Basic MSA context switching support This patch adds support for context switching the MSA vector registers. These 128 bit vector registers are aliased with the FP registers - an FP register accesses the least significant bits of the vector register with which it is aliased (ie. the register with the same index). Due to both this & the requirement that the scalar FPU must be 64-bit (FR=1) if enabled at the same time as MSA the kernel will enable MSA & scalar FP at the same time for tasks which use MSA. If we restore the MSA vector context then we might as well enable the scalar FPU since the reason it was left disabled was to allow for lazy FP context restoring - but we just restored the FP context as it's a subset of the vector context. If we restore the FP context and have previously used MSA then we have to restore the whole vector context anyway (see comment in enable_restore_fp_context for details) so similarly we might as well enable MSA. Thus if a task does not use MSA then it will continue to behave as without this patch - the scalar FP context will be saved & restored as usual. But if a task executes an MSA instruction then it will save & restore the vector context forever more. Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6431/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/asmmacro.h | 70 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) (limited to 'arch/mips/include/asm/asmmacro.h') diff --git a/arch/mips/include/asm/asmmacro.h b/arch/mips/include/asm/asmmacro.h index f571db371b3e..fe3b03c793e5 100644 --- a/arch/mips/include/asm/asmmacro.h +++ b/arch/mips/include/asm/asmmacro.h @@ -328,4 +328,74 @@ .endm #endif + .macro msa_save_all thread + st_d 0, THREAD_FPR0, \thread + st_d 1, THREAD_FPR1, \thread + st_d 2, THREAD_FPR2, \thread + st_d 3, THREAD_FPR3, \thread + st_d 4, THREAD_FPR4, \thread + st_d 5, THREAD_FPR5, \thread + st_d 6, THREAD_FPR6, \thread + st_d 7, THREAD_FPR7, \thread + st_d 8, THREAD_FPR8, \thread + st_d 9, THREAD_FPR9, \thread + st_d 10, THREAD_FPR10, \thread + st_d 11, THREAD_FPR11, \thread + st_d 12, THREAD_FPR12, \thread + st_d 13, THREAD_FPR13, \thread + st_d 14, THREAD_FPR14, \thread + st_d 15, THREAD_FPR15, \thread + st_d 16, THREAD_FPR16, \thread + st_d 17, THREAD_FPR17, \thread + st_d 18, THREAD_FPR18, \thread + st_d 19, THREAD_FPR19, \thread + st_d 20, THREAD_FPR20, \thread + st_d 21, THREAD_FPR21, \thread + st_d 22, THREAD_FPR22, \thread + st_d 23, THREAD_FPR23, \thread + st_d 24, THREAD_FPR24, \thread + st_d 25, THREAD_FPR25, \thread + st_d 26, THREAD_FPR26, \thread + st_d 27, THREAD_FPR27, \thread + st_d 28, THREAD_FPR28, \thread + st_d 29, THREAD_FPR29, \thread + st_d 30, THREAD_FPR30, \thread + st_d 31, THREAD_FPR31, \thread + .endm + + .macro msa_restore_all thread + ld_d 0, THREAD_FPR0, \thread + ld_d 1, THREAD_FPR1, \thread + ld_d 2, THREAD_FPR2, \thread + ld_d 3, THREAD_FPR3, \thread + ld_d 4, THREAD_FPR4, \thread + ld_d 5, THREAD_FPR5, \thread + ld_d 6, THREAD_FPR6, \thread + ld_d 7, THREAD_FPR7, \thread + ld_d 8, THREAD_FPR8, \thread + ld_d 9, THREAD_FPR9, \thread + ld_d 10, THREAD_FPR10, \thread + ld_d 11, THREAD_FPR11, \thread + ld_d 12, THREAD_FPR12, \thread + ld_d 13, THREAD_FPR13, \thread + ld_d 14, THREAD_FPR14, \thread + ld_d 15, THREAD_FPR15, \thread + ld_d 16, THREAD_FPR16, \thread + ld_d 17, THREAD_FPR17, \thread + ld_d 18, THREAD_FPR18, \thread + ld_d 19, THREAD_FPR19, \thread + ld_d 20, THREAD_FPR20, \thread + ld_d 21, THREAD_FPR21, \thread + ld_d 22, THREAD_FPR22, \thread + ld_d 23, THREAD_FPR23, \thread + ld_d 24, THREAD_FPR24, \thread + ld_d 25, THREAD_FPR25, \thread + ld_d 26, THREAD_FPR26, \thread + ld_d 27, THREAD_FPR27, \thread + ld_d 28, THREAD_FPR28, \thread + ld_d 29, THREAD_FPR29, \thread + ld_d 30, THREAD_FPR30, \thread + ld_d 31, THREAD_FPR31, \thread + .endm + #endif /* _ASM_ASMMACRO_H */ -- cgit v1.2.3