From b314ace942506718f3c3bc2787f700bf49d84ea2 Mon Sep 17 00:00:00 2001 From: "Luck, Tony" Date: Wed, 9 Mar 2016 16:40:48 -0800 Subject: [PATCH] EDAC/sb_edac: Fix computation of channel address [ Upstream commit eb1af3b71f9d83e45f2fd2fd649356e98e1c582c ] Large memory Haswell-EX systems with multiple DIMMs per channel were sometimes reporting the wrong DIMM. Found three problems: 1) Debug printouts for socket and channel interleave were not interpreting the register fields correctly. The socket interleave field is a 2^X value (0=1, 1=2, 2=4, 3=8). The channel interleave is X+1 (0=1, 1=2, 2=3. 3=4). 2) Actual use of the socket interleave value didn't interpret as 2^X 3) Conversion of address to channel address was complicated, and wrong. Signed-off-by: Tony Luck Acked-by: Aristeu Rozanski Cc: Borislav Petkov Cc: Linus Torvalds Cc: Mauro Carvalho Chehab Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-edac@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- drivers/edac/sb_edac.c | 26 ++++++++++---------------- 1 file changed, 10 insertions(+), 16 deletions(-) diff --git a/drivers/edac/sb_edac.c b/drivers/edac/sb_edac.c index cd6b9c7..adcc628 100644 --- a/drivers/edac/sb_edac.c +++ b/drivers/edac/sb_edac.c @@ -1043,8 +1043,8 @@ static void get_memory_layout(const struct mem_ctl_info *mci) edac_dbg(0, "TAD#%d: up to %u.%03u GB (0x%016Lx), socket interleave %d, memory interleave %d, TGT: %d, %d, %d, %d, reg=0x%08x\n", n_tads, gb, (mb*1000)/1024, ((u64)tmp_mb) << 20L, - (u32)TAD_SOCK(reg), - (u32)TAD_CH(reg), + (u32)(1 << TAD_SOCK(reg)), + (u32)TAD_CH(reg) + 1, (u32)TAD_TGT0(reg), (u32)TAD_TGT1(reg), (u32)TAD_TGT2(reg), @@ -1316,7 +1316,7 @@ static int get_memory_error_data(struct mem_ctl_info *mci, } ch_way = TAD_CH(reg) + 1; - sck_way = TAD_SOCK(reg) + 1; + sck_way = 1 << TAD_SOCK(reg); if (ch_way == 3) idx = addr >> 6; @@ -1373,7 +1373,7 @@ static int get_memory_error_data(struct mem_ctl_info *mci, n_tads, addr, limit, - (u32)TAD_SOCK(reg), + sck_way, ch_way, offset, idx, @@ -1388,18 +1388,12 @@ static int get_memory_error_data(struct mem_ctl_info *mci, offset, addr); return -EINVAL; } - addr -= offset; - /* Store the low bits [0:6] of the addr */ - ch_addr = addr & 0x7f; - /* Remove socket wayness and remove 6 bits */ - addr >>= 6; - addr = div_u64(addr, sck_xch); -#if 0 - /* Divide by channel way */ - addr = addr / ch_way; -#endif - /* Recover the last 6 bits */ - ch_addr |= addr << 6; + + ch_addr = addr - offset; + ch_addr >>= (6 + shiftup); + ch_addr /= ch_way * sck_way; + ch_addr <<= (6 + shiftup); + ch_addr |= addr & ((1 << (6 + shiftup)) - 1); /* * Step 3) Decode rank -- 2.7.4