[PATCH v6 0/4] iMC SMBUS driver and DIMM bus probing

Andy Lutomirski
2013-12-21T01:45:23Z

Intel LGA2011 machines have dedicated SMBUS controllers for DIMM
sockets. Because they're dedicated, they can be safely and accurately
probed, since all devices on them are known to be attached to DIMMs.
The devices found are:
- SPD EEPROMs
- TSODs (Temperature Sensor on DIMMs)
- Other interesting things, with drivers hopefully to follow...

This patch series adds a simple generic layer for probing for DIMMs over
SMBUS and an i2c bus driver for the iMC controller found on Intel
LGA2011 chips.

It now uses only modern infrastructure -- new-style I2C probing and the
at24 (instead of eeprom) driver.

I've tested this on a Core i7 Extreme and on a Xeon E5 server. I haven't
tested it on an LGA2011 Ivy Bridge box, since I don't have one.

Patches 1-3 are useful even without patch 4. I'm still hoping for feedback
on patch 4.

Changes from v5:
- Rebase to a6ddeee32dad (i.e. -linus from today) and re-test

Changes from v4:
- Added the sb_edac changes -- i2c_imc and sb_edac can now coexist
- Added some paranoid race detection.
- The driver now confirms its ability to claim software control of the SMBUS
master. This prevents unpleasant problems on systems that enable CLTT
(closed loop thermal throttling).
- Reordered the patches so that the DIMM bus code is last.

Changes from v3:
- Dropped redundant "tsod" driver
- Dropped eeprom modalias
- Switched to probing for the "eeprom" and "jc42"

Andy Lutomirski (4):
Move Intel SNB device ids from sb_edac to pci_ids.h
sb_edac: Claim a different PCI device
i2c_imc: New driver for Intel's iMC, found on LGA2011 chips
i2c, i2c_imc: Add DIMM bus code

drivers/edac/sb_edac.c | 32 +--
drivers/i2c/busses/Kconfig | 19 ++
drivers/i2c/busses/Makefile | 5 +
drivers/i2c/busses/dimm-bus.c | 97 ++++++++
drivers/i2c/busses/i2c-imc.c | 562 ++++++++++++++++++++++++++++++++++++++++++
include/linux/i2c/dimm-bus.h | 24 ++
include/linux/pci_ids.h | 15 ++
7 files changed, 723 insertions(+), 31 deletions(-)
create mode 100644 drivers/i2c/busses/dimm-bus.c
create mode 100644 drivers/i2c/busses/i2c-imc.c
create mode 100644 include/linux/i2c/dimm-bus.h

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1.8.3.1