[PATCH] ARC: guard dsp early init against non ARCv2

From: Eugeniy Paltsev
Date: Tue Apr 28 2020 - 14:50:43 EST


As of today we guard early DSP init code with
ARC_AUX_DSP_BUILD (0x7A) BCR check to verify that we have
CPU with DSP configured. However that's not enough as in
ARCv1 CPU the same BCR (0x7A) is used for checking MUL/MAC
instructions presence.

So, let's guard DSP early init against non ARCv2.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
---
arch/arc/include/asm/dsp-impl.h | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/arc/include/asm/dsp-impl.h b/arch/arc/include/asm/dsp-impl.h
index e1aa212ca6eb..e64d945ae7df 100644
--- a/arch/arc/include/asm/dsp-impl.h
+++ b/arch/arc/include/asm/dsp-impl.h
@@ -15,12 +15,14 @@

/* clobbers r5 register */
.macro DSP_EARLY_INIT
+#if defined(CONFIG_ISA_ARCV2)
lr r5, [ARC_AUX_DSP_BUILD]
bmsk r5, r5, 7
breq r5, 0, 1f
mov r5, DSP_CTRL_DISABLED_ALL
sr r5, [ARC_AUX_DSP_CTRL]
1:
+#endif
.endm

/* clobbers r10, r11 registers pair */
--
2.21.1