[PATCH v2 05/15] EDAC/synopsys: Add multi-ranked memory support

[Serge Semin]

DW uMCTL2 DDRC supports multi-rank memory attached to the controller. If
so the MSTR.active_ranks field will be set with the populated ranks
bitfield. It is permitted to have one, two or four ranks activated at a
time [1]. Since we now have the number of ranks determined in the
controller configuration detection procedure, it can be easily used for
accordingly extending the MCI chip-select layer. In case of the ECC errors
the affected rank will be read from the CE/UE address CSRs [2].

Note we need to drop the ranks from the total memory size calculation
since multiple ranks are taken into account by means of the layer[0]
definition.

[1] DesignWare® Cores Enhanced Universal DDR Memory Controller (uMCTL2)
    Databook, Version 3.91a, October 2020, p.739
[2] DesignWare® Cores Enhanced Universal DDR Memory Controller (uMCTL2)
    Databook, Version 3.91a, October 2020, p.821, p.832

Signed-off-by: Serge Semin <Sergey.Semin at baikalelectronics.ru>
---
 drivers/edac/synopsys_edac.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/edac/synopsys_edac.c b/drivers/edac/synopsys_edac.c
index e1e5468acbd2..d5d82531719b 100644
--- a/drivers/edac/synopsys_edac.c
+++ b/drivers/edac/synopsys_edac.c
@@ -23,9 +23,6 @@
 
 #include "edac_module.h"
 
-/* Number of cs_rows needed per memory controller */
-#define SNPS_EDAC_NR_CSROWS		1
-
 /* Number of channels per memory controller */
 #define SNPS_EDAC_NR_CHANS		1
 
@@ -795,7 +792,7 @@ static void snps_handle_error(struct mem_ctl_info *mci, struct snps_ecc_status *
 
 		edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, p->ce_cnt,
 				     PHYS_PFN(sys), offset_in_page(sys),
-				     pinf->syndrome, 0, 0, -1,
+				     pinf->syndrome, pinf->sdram.rank, 0, -1,
 				     priv->message, "");
 	}
 
@@ -812,7 +809,7 @@ static void snps_handle_error(struct mem_ctl_info *mci, struct snps_ecc_status *
 
 		edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, p->ue_cnt,
 				     PHYS_PFN(sys), offset_in_page(sys),
-				     pinf->syndrome, 0, 0, -1,
+				     pinf->syndrome, pinf->sdram.rank, 0, -1,
 				     priv->message, "");
 	}
 
@@ -1411,10 +1408,7 @@ static u64 snps_get_sdram_size(struct snps_edac_priv *priv)
 			size++;
 	}
 
-	for (i = 0; i < DDR_MAX_RANK_WIDTH; i++) {
-		if (map->rank[i] != DDR_ADDRMAP_UNUSED)
-			size++;
-	}
+	/* Skip the ranks since the multi-rankness is determined by layer[0] */
 
 	return 1ULL << (size + priv->info.dq_width);
 }
@@ -1468,7 +1462,7 @@ static struct mem_ctl_info *snps_mc_create(struct snps_edac_priv *priv)
 	struct mem_ctl_info *mci;
 
 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
-	layers[0].size = SNPS_EDAC_NR_CSROWS;
+	layers[0].size = priv->info.ranks;
 	layers[0].is_virt_csrow = true;
 	layers[1].type = EDAC_MC_LAYER_CHANNEL;
 	layers[1].size = SNPS_EDAC_NR_CHANS;
-- 
2.37.2