3.19.8-ckt18 -stable review patch. If anyone has any objections, please let me
know.
---8<------------------------------------------------------------
From: "Luck, Tony" <tony.l...@intel.com>
commit eb1af3b71f9d83e45f2fd2fd649356e98e1c582c upstream.
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 <tony.l...@intel.com>
Acked-by: Aristeu Rozanski <aroza...@redhat.com>
Cc: Borislav Petkov <b...@alien8.de>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Mauro Carvalho Chehab <mche...@osg.samsung.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: linux-e...@vger.kernel.org
Signed-off-by: Ingo Molnar <mi...@kernel.org>
Signed-off-by: Kamal Mostafa <ka...@canonical.com>
---
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 1acf57b..0af67b5 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
