EDAC/sb_edac: Fix computation of channel address
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.luck@intel.com>
Acked-by: Aristeu Rozanski <arozansk@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-edac@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/drivers/edac/sb_edac.c b/drivers/edac/sb_edac.c
index e438ee5..34e54a3 100644
--- a/drivers/edac/sb_edac.c
+++ b/drivers/edac/sb_edac.c
@@ -1839,8 +1839,8 @@
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),
@@ -2118,7 +2118,7 @@
}
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;
@@ -2175,7 +2175,7 @@
n_tads,
addr,
limit,
- (u32)TAD_SOCK(reg),
+ sck_way,
ch_way,
offset,
idx,
@@ -2190,18 +2190,12 @@
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