Commit 091be550 authored Jan 30, 2015 by Paul Burton Committed by Ralf Baechle Mar 27, 2015

MIPS: clear MSACSR cause bits when handling MSA FP exception



Much like for traditional scalar FP exceptions, the cause bits in the
MSACSR register need to be cleared following an MSA FP exception.
Without doing so the exception will simply be raised again whenever
the kernel restores MSACSR from a tasks saved context, leading to
undesirable spurious exceptions. Clear the cause bits from the
handle_msa_fpe function, mirroring the way handle_fpe clears the
cause bits in FCSR.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9164/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

parent e1bebbab

arch/mips/kernel/genex.S

+10 −1

Original line number	Diff line number	Diff line
		@@ -368,6 +368,15 @@ NESTED(nmi_handler, PT_SIZE, sp)
		STI
		.endm

		.macro __build_clear_msa_fpe
		_cfcmsa a1, MSA_CSR
		li a2, ~(0x3f << 12)
		and a1, a1, a2
		_ctcmsa MSA_CSR, a1
		TRACE_IRQS_ON
		STI
		.endm

		.macro __build_clear_ade
		MFC0 t0, CP0_BADVADDR
		PTR_S t0, PT_BVADDR(sp)
		@@ -426,7 +435,7 @@ NESTED(nmi_handler, PT_SIZE, sp)
		BUILD_HANDLER cpu cpu sti silent /* #11 */
		BUILD_HANDLER ov ov sti silent /* #12 */
		BUILD_HANDLER tr tr sti silent /* #13 */
		BUILD_HANDLER msa_fpe msa_fpe sti silent /* #14 */
		BUILD_HANDLER msa_fpe msa_fpe msa_fpe silent /* #14 */
		BUILD_HANDLER fpe fpe fpe silent /* #15 */
		BUILD_HANDLER ftlb ftlb none silent /* #16 */
		BUILD_HANDLER msa msa sti silent /* #21 */

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