[PATCH 2/2] ARC: add SMP_CACHE_BYTES value validate

From: Eugeniy Paltsev
Date: Thu Jul 26 2018 - 07:08:53 EST


Check that SMP_CACHE_BYTES (and hence ARCH_DMA_MINALIGN) is larger
or equal to any cache line length by comparing it with values
previously read from ARC cache BCR registers.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
---
arch/arc/mm/cache.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index 9dbe645ee127..b95365e1253a 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -1246,6 +1246,16 @@ void __init arc_cache_init_master(void)
}
}

+ /*
+ * Check that SMP_CACHE_BYTES (and hence ARCH_DMA_MINALIGN) is larger
+ * or equal to any cache line length.
+ */
+ BUILD_BUG_ON_MSG(L1_CACHE_BYTES > SMP_CACHE_BYTES,
+ "SMP_CACHE_BYTES must be >= any cache line length");
+ if (is_isa_arcv2() && (l2_line_sz > SMP_CACHE_BYTES))
+ panic("L2 Cache line [%d] > kernel Config [%d]\n",
+ l2_line_sz, SMP_CACHE_BYTES);
+
/* Note that SLC disable not formally supported till HS 3.0 */
if (is_isa_arcv2() && l2_line_sz && !slc_enable)
arc_slc_disable();
--
2.14.4