ARM: 8195/1: vfp: Bounce undefined instructions in vectored mode

Certain ARM CPU implementations (e.g. Cortex-A15) may not raise a
floating- point exception whenever deprecated short-vector VFP
instructions are executed. Instead these instructions are treated
as UNALLOCATED. Change the VFP exception handling code to emulate
short-vector instructions even if FPEXC exception bits are not
set.

Signed-off-by: Stepan Moskovchenko <[e-mail]>
Tested-by: Will Deacon <[e-mail]>
Tested-by: Rob Clark <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>
Signed-off-by: Russell King <[e-mail]>

arch/arm/vfp/vfphw.S

···
 	tst	r5, #FPSCR_IXE
 	bne	process_exception
 
+	tst	r5, #FPSCR_LENGTH_MASK
+	beq	skip
+	orr	r1, r1, #FPEXC_DEX
+	b	process_exception
+skip:
+
 	@ Fall into hand on to next handler - appropriate coproc instr
 	@ not recognised by VFP