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Diffstat (limited to 'Documentation/edac.txt')
| -rw-r--r-- | Documentation/edac.txt | 120 |
1 files changed, 12 insertions, 108 deletions
diff --git a/Documentation/edac.txt b/Documentation/edac.txt index 9ee774de57c..73fff13e848 100644 --- a/Documentation/edac.txt +++ b/Documentation/edac.txt @@ -6,7 +6,7 @@ Written by Doug Thompson <dougthompson@xmission.com> 7 Dec 2005 17 Jul 2007 Updated -(c) Mauro Carvalho Chehab <mchehab@redhat.com> +(c) Mauro Carvalho Chehab 05 Aug 2009 Nehalem interface EDAC is maintained and written by: @@ -232,116 +232,20 @@ EDAC control and attribute files. In 'mcX' directories are EDAC control and attribute files for -this 'X' instance of the memory controllers: - - -Counter reset control file: - - 'reset_counters' - - This write-only control file will zero all the statistical counters - for UE and CE errors. Zeroing the counters will also reset the timer - indicating how long since the last counter zero. This is useful - for computing errors/time. Since the counters are always reset at - driver initialization time, no module/kernel parameter is available. - - RUN TIME: echo "anything" >/sys/devices/system/edac/mc/mc0/counter_reset - - This resets the counters on memory controller 0 - - -Seconds since last counter reset control file: - - 'seconds_since_reset' - - This attribute file displays how many seconds have elapsed since the - last counter reset. This can be used with the error counters to - measure error rates. - - - -Memory Controller name attribute file: - - 'mc_name' - - This attribute file displays the type of memory controller - that is being utilized. - - -Total memory managed by this memory controller attribute file: - - 'size_mb' - - This attribute file displays, in count of megabytes, of memory - that this instance of memory controller manages. - - -Total Uncorrectable Errors count attribute file: - - 'ue_count' - - This attribute file displays the total count of uncorrectable - errors that have occurred on this memory controller. If panic_on_ue - is set this counter will not have a chance to increment, - since EDAC will panic the system. - - -Total UE count that had no information attribute fileY: - - 'ue_noinfo_count' - - This attribute file displays the number of UEs that have occurred - with no information as to which DIMM slot is having errors. - - -Total Correctable Errors count attribute file: - - 'ce_count' - - This attribute file displays the total count of correctable - errors that have occurred on this memory controller. This - count is very important to examine. CEs provide early - indications that a DIMM is beginning to fail. This count - field should be monitored for non-zero values and report - such information to the system administrator. - - -Total Correctable Errors count attribute file: - - 'ce_noinfo_count' - - This attribute file displays the number of CEs that - have occurred wherewith no informations as to which DIMM slot - is having errors. Memory is handicapped, but operational, - yet no information is available to indicate which slot - the failing memory is in. This count field should be also - be monitored for non-zero values. - -Device Symlink: - - 'device' - - Symlink to the memory controller device. - -Sdram memory scrubbing rate: - - 'sdram_scrub_rate' - - Read/Write attribute file that controls memory scrubbing. The scrubbing - rate is set by writing a minimum bandwidth in bytes/sec to the attribute - file. The rate will be translated to an internal value that gives at - least the specified rate. - - Reading the file will return the actual scrubbing rate employed. - - If configuration fails or memory scrubbing is not implemented, the value - of the attribute file will be -1. +this 'X' instance of the memory controllers. +For a description of the sysfs API, please see: + Documentation/ABI/testing/sysfs/devices-edac ============================================================================ 'csrowX' DIRECTORIES +When CONFIG_EDAC_LEGACY_SYSFS is enabled, the sysfs will contain the +csrowX directories. As this API doesn't work properly for Rambus, FB-DIMMs +and modern Intel Memory Controllers, this is being deprecated in favor +of dimmX directories. + In the 'csrowX' directories are EDAC control and attribute files for this 'X' instance of csrow: @@ -646,7 +550,7 @@ installs itself as: /sys/devices/systm/edac/test-instance in this directory are various controls, a symlink and one or more 'instance' -directorys. +directories. The standard default controls are: @@ -734,14 +638,14 @@ were done at i7core_edac driver. This chapter will cover those differences associated with a physical CPU socket. Each MC have 3 physical read channels, 3 physical write channels and - 3 logic channels. The driver currenty sees it as just 3 channels. + 3 logic channels. The driver currently sees it as just 3 channels. Each channel can have up to 3 DIMMs. The minimum known unity is DIMMs. There are no information about csrows. As EDAC API maps the minimum unity is csrows, the driver sequencially maps channel/dimm into different csrows. - For example, suposing the following layout: + For example, supposing the following layout: Ch0 phy rd0, wr0 (0x063f4031): 2 ranks, UDIMMs dimm 0 1024 Mb offset: 0, bank: 8, rank: 1, row: 0x4000, col: 0x400 dimm 1 1024 Mb offset: 4, bank: 8, rank: 1, row: 0x4000, col: 0x400 |