[PATCH 3/5] kvx: robustify i/d cache startup

[jvetter@kalrayinc.com]

From: Julian Hascoet <jhascoet@kalrayinc.com>

Make sure the i/d caches start clean after enabling them. Also, make
sure there are no outstanding loads and/or stores before enabling them.
This might fix incoherency issues between caches and memory during the
boot of barebox.

Signed-off-by: Julien Hascoet <jhascoet@kalrayinc.com>
Signed-off-by: Julian Vetter <jvetter@kalrayinc.com>
Reviewed-by: Yann Sionneau <ysionneau@kalrayinc.com>
Reviewed-by: Jonathan Borne <jborne@kalrayinc.com>
---
 arch/kvx/cpu/start.S | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/kvx/cpu/start.S b/arch/kvx/cpu/start.S
index 342c7d38a5..853676a836 100644
--- a/arch/kvx/cpu/start.S
+++ b/arch/kvx/cpu/start.S
@@ -50,10 +50,21 @@ ENTRY(kvx_start)
 	;;
 	/* Setup default processor status */
 	make $r25 = PS_WFXL_START_VALUE
+	/* Make sure there is no outstanding
+	 * load(s)/store(s) before dcache enable
+	 */
+	fence
 	;;
 	wfxl $ps, $r25
 	;;
+	/* Make sure icache starts clean */
+	i1inval
+	;;
+	barrier
+	;;
 	make $r25 = PCR_WFXM_START_VALUE
+	/* Make sure dcache starts clean */
+	d1inval
 	;;
 	wfxm $pcr, $r25
 	;;
-- 
2.34.1