Commit 24b647a0 authored by Catalin Marinas's avatar Catalin Marinas
Browse files

ARMv7: Branch over conditional undefined instructions in vfphw.S 



On ARMv7, conditional undefined instructions may generate exceptions
even if the condition is not met. The vfphw.S contains the FPINST and
FPINST2 access instructions which may not be present on processors with
synchronous VFP exceptions.

Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent c30c2f99

arch/arm/vfp/vfphw.S

+18 −9
Original line number Diff line number Diff line
@@ -101,9 +101,12 @@ ENTRY(vfp_support_entry) 
	VFPFSTMIA r4, r5		@ save the working registers

	VFPFMRX	r5, FPSCR		@ current status

	tst	r1, #FPEXC_EX		@ is there additional state to save?

	VFPFMRX	r6, FPINST, NE		@ FPINST (only if FPEXC.EX is set)

	tstne	r1, #FPEXC_FP2V		@ is there an FPINST2 to read?

	VFPFMRX	r8, FPINST2, NE		@ FPINST2 if needed (and present)

	beq	1f

	VFPFMRX	r6, FPINST		@ FPINST (only if FPEXC.EX is set)

	tst	r1, #FPEXC_FP2V		@ is there an FPINST2 to read?

	beq	1f

	VFPFMRX	r8, FPINST2		@ FPINST2 if needed (and present)

1:

	stmia	r4, {r1, r5, r6, r8}	@ save FPEXC, FPSCR, FPINST, FPINST2

					@ and point r4 at the word at the

					@ start of the register dump
@@ -117,9 +120,12 @@ no_old_VFP_process: 
					@ FPEXC is in a safe state

	ldmia	r10, {r1, r5, r6, r8}	@ load FPEXC, FPSCR, FPINST, FPINST2

	tst	r1, #FPEXC_EX		@ is there additional state to restore?

	VFPFMXR	FPINST, r6, NE		@ restore FPINST (only if FPEXC.EX is set)

	tstne	r1, #FPEXC_FP2V		@ is there an FPINST2 to write?

	VFPFMXR	FPINST2, r8, NE		@ FPINST2 if needed (and present)

	beq	1f

	VFPFMXR	FPINST, r6		@ restore FPINST (only if FPEXC.EX is set)

	tst	r1, #FPEXC_FP2V		@ is there an FPINST2 to write?

	beq	1f

	VFPFMXR	FPINST2, r8		@ FPINST2 if needed (and present)

1:

	VFPFMXR	FPSCR, r5		@ restore status



check_for_exception:
@@ -175,9 +181,12 @@ ENTRY(vfp_save_state) 
	VFPFSTMIA r0, r2		@ save the working registers

	VFPFMRX	r2, FPSCR		@ current status

	tst	r1, #FPEXC_EX		@ is there additional state to save?

	VFPFMRX	r3, FPINST, NE		@ FPINST (only if FPEXC.EX is set)

	tstne	r1, #FPEXC_FP2V		@ is there an FPINST2 to read?

	VFPFMRX	r12, FPINST2, NE	@ FPINST2 if needed (and present)

	beq	1f

	VFPFMRX	r3, FPINST		@ FPINST (only if FPEXC.EX is set)

	tst	r1, #FPEXC_FP2V		@ is there an FPINST2 to read?

	beq	1f

	VFPFMRX	r12, FPINST2		@ FPINST2 if needed (and present)

1:

	stmia	r0, {r1, r2, r3, r12}	@ save FPEXC, FPSCR, FPINST, FPINST2

	mov	pc, lr

ENDPROC(vfp_save_state)

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