mv_ddr armada-18.09 for ECC DIMM

[nanasiParticipant]

Hi,
Version armada-18.09 has been released.
An inexplicable behavior was resolved in this version(mv_ddr-devel-18.09.1).

I replaced the 4GB NonECC DIMM with a 16GB ECC DIMM two months ago.
Linux kernel was frequently logging errors since that.
[ 351.562134] Synchronous External Abort: synchronous external abort (0x92000210) at 0x0000007fa4f5e6e0
After occurrence of an error,
the register MC6_CH0_ECC_1BIT_ERR_COUNTER_REG has been incremented by several hundreds or more.

It does not happen if I modify mv_ddr source to disable ECC.

diff --git a/mv_ddr_topology.c b/mv_ddr_topology.c
index eb1b47e..80e7b18 100644
--- a/mv_ddr_topology.c
+++ b/mv_ddr_topology.c
@@ -295,6 +295,10 @@ unsigned short mv_ddr_bus_bit_mask_get(void)
                        pri_and_ext_bus_width = 0x0;
                }

+#if 1
+               bus_width_ext = MV_DDR_BUS_WIDTH_EXT_0;
+               printf("mv_ddr: ECC disabled.\n");
+#endif
                if (bus_width_ext == MV_DDR_BUS_WIDTH_EXT_8)
                        pri_and_ext_bus_width |= 1 << (octets_per_if_num - 1);
        }

Also, it occurs only after a reboot or reset by signal CP_MR#.
It does not occur after a power-on reset.

This
commit fixed it.

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