Commits
Mauro Carvalho Chehab committed 24bef66e74d
edac: Fix the dimm filling for csrows-based layouts
The driver is currently filling data in a wrong way, on drivers
for csrows-based memory controller, when the first layer is a
csrow.
This is not easily to notice, as, in general, memories are
filed in dual, interleaved, symetric mode, as very few memory
controllers support asymetric modes.
While digging into a bug for i82795_edac driver, the asymetric
mode there is now working, allowing us to fill the machine with
4x1GB ranks at channel 0, and 2x512GB at channel 1:
Channel 0 ranks:
EDAC DEBUG: i82975x_init_csrows: DIMM A0: from page 0x00000000 to 0x0003ffff (size: 0x00040000 pages)
EDAC DEBUG: i82975x_init_csrows: DIMM A1: from page 0x00040000 to 0x0007ffff (size: 0x00040000 pages)
EDAC DEBUG: i82975x_init_csrows: DIMM A2: from page 0x00080000 to 0x000bffff (size: 0x00040000 pages)
EDAC DEBUG: i82975x_init_csrows: DIMM A3: from page 0x000c0000 to 0x000fffff (size: 0x00040000 pages)
Channel 1 ranks:
EDAC DEBUG: i82975x_init_csrows: DIMM B0: from page 0x00100000 to 0x0011ffff (size: 0x00020000 pages)
EDAC DEBUG: i82975x_init_csrows: DIMM B1: from page 0x00120000 to 0x0013ffff (size: 0x00020000 pages)
Instead of properly showing the memories as such, before this patch, it
shows the memory layout as:
+-----------------------------------+
| mc0 |
| csrow0 | csrow1 | csrow2 |
----------+-----------------------------------+
channel1: | 1024 MB | 1024 MB | 512 MB |
channel0: | 1024 MB | 1024 MB | 512 MB |
----------+-----------------------------------+
as if both channels were symetric, grouping the DIMMs on a wrong
layout.
After this patch, the memory is correctly represented.
So, for csrows at layers[0], it shows:
+-----------------------------------------------+
| mc0 |
| csrow0 | csrow1 | csrow2 | csrow3 |
----------+-----------------------------------------------+
channel1: | 512 MB | 512 MB | 0 MB | 0 MB |
channel0: | 1024 MB | 1024 MB | 1024 MB | 1024 MB |
----------+-----------------------------------------------+
For csrows at layers[1], it shows:
+-----------------------+
| mc0 |
| channel0 | channel1 |
--------+-----------------------+
csrow3: | 1024 MB | 0 MB |
csrow2: | 1024 MB | 0 MB |
--------+-----------------------+
csrow1: | 1024 MB | 512 MB |
csrow0: | 1024 MB | 512 MB |
--------+-----------------------+
So, no matter of what comes first, the information between
channel and csrow will be properly represented.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>