[PATCH 08/18] EDAC/synopsys: Parse ADDRMAP[0] CSR for multi-ranks case only

[Serge Semin]

The ADDRMAP[0] CSR contains the SDRAM Rank bits mapping. Obviously it's
applicable for the multi-ranked memory only. If either the attached memory
isn't multi-ranked or the controller simply doesn't support the multi-rank
memory, parsing the ADDRMAP[0] CSR will be not just pointless, but in the
later case erroneous since the CSR may contain garbage data. So make sure
the ADDRMAP[0] register is only parsed if the multi-ranked memory setup
has been detected.

Signed-off-by: Serge Semin <Sergey.Semin at baikalelectronics.ru>
---
 drivers/edac/synopsys_edac.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/edac/synopsys_edac.c b/drivers/edac/synopsys_edac.c
index 998600670c75..e7f8d448850b 100644
--- a/drivers/edac/synopsys_edac.c
+++ b/drivers/edac/synopsys_edac.c
@@ -1143,9 +1143,12 @@ static void snps_setup_bg_address_map(struct snps_edac_priv *priv, u32 *addrmap)
 
 static void snps_setup_rank_address_map(struct snps_edac_priv *priv, u32 *addrmap)
 {
-	priv->rank_shift[0] = ((addrmap[0] & RANK_MAX_VAL_MASK) ==
-				RANK_MAX_VAL_MASK) ? 0 : ((addrmap[0] &
-				RANK_MAX_VAL_MASK) + RANK_B0_BASE);
+	/* Ranks mapping is unavailable for the single-ranked memory */
+	if (priv->info.ranks > 1) {
+		priv->rank_shift[0] = ((addrmap[0] & RANK_MAX_VAL_MASK) ==
+					RANK_MAX_VAL_MASK) ? 0 : ((addrmap[0] &
+					RANK_MAX_VAL_MASK) + RANK_B0_BASE);
+	}
 }
 
 /**
-- 
2.35.1