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-rw-r--r--Documentation/drivers/edac/edac.txt34
1 files changed, 17 insertions, 17 deletions
diff --git a/Documentation/drivers/edac/edac.txt b/Documentation/drivers/edac/edac.txt
index d37191fe5681..70d96a62e5e1 100644
--- a/Documentation/drivers/edac/edac.txt
+++ b/Documentation/drivers/edac/edac.txt
@@ -21,7 +21,7 @@ within the computer system. In the initial release, memory Correctable Errors
21 21
22Detecting CE events, then harvesting those events and reporting them, 22Detecting CE events, then harvesting those events and reporting them,
23CAN be a predictor of future UE events. With CE events, the system can 23CAN be a predictor of future UE events. With CE events, the system can
24continue to operate, but with less safety. Preventive maintainence and 24continue to operate, but with less safety. Preventive maintenance and
25proactive part replacement of memory DIMMs exhibiting CEs can reduce 25proactive part replacement of memory DIMMs exhibiting CEs can reduce
26the likelihood of the dreaded UE events and system 'panics'. 26the likelihood of the dreaded UE events and system 'panics'.
27 27
@@ -29,13 +29,13 @@ the likelihood of the dreaded UE events and system 'panics'.
29In addition, PCI Bus Parity and SERR Errors are scanned for on PCI devices 29In addition, PCI Bus Parity and SERR Errors are scanned for on PCI devices
30in order to determine if errors are occurring on data transfers. 30in order to determine if errors are occurring on data transfers.
31The presence of PCI Parity errors must be examined with a grain of salt. 31The presence of PCI Parity errors must be examined with a grain of salt.
32There are several addin adapters that do NOT follow the PCI specification 32There are several add-in adapters that do NOT follow the PCI specification
33with regards to Parity generation and reporting. The specification says 33with regards to Parity generation and reporting. The specification says
34the vendor should tie the parity status bits to 0 if they do not intend 34the vendor should tie the parity status bits to 0 if they do not intend
35to generate parity. Some vendors do not do this, and thus the parity bit 35to generate parity. Some vendors do not do this, and thus the parity bit
36can "float" giving false positives. 36can "float" giving false positives.
37 37
38The PCI Parity EDAC device has the ability to "skip" known flakey 38The PCI Parity EDAC device has the ability to "skip" known flaky
39cards during the parity scan. These are set by the parity "blacklist" 39cards during the parity scan. These are set by the parity "blacklist"
40interface in the sysfs for PCI Parity. (See the PCI section in the sysfs 40interface in the sysfs for PCI Parity. (See the PCI section in the sysfs
41section below.) There is also a parity "whitelist" which is used as 41section below.) There is also a parity "whitelist" which is used as
@@ -101,7 +101,7 @@ Memory Controller (mc) Model
101 101
102First a background on the memory controller's model abstracted in EDAC. 102First a background on the memory controller's model abstracted in EDAC.
103Each mc device controls a set of DIMM memory modules. These modules are 103Each mc device controls a set of DIMM memory modules. These modules are
104layed out in a Chip-Select Row (csrowX) and Channel table (chX). There can 104laid out in a Chip-Select Row (csrowX) and Channel table (chX). There can
105be multiple csrows and two channels. 105be multiple csrows and two channels.
106 106
107Memory controllers allow for several csrows, with 8 csrows being a typical value. 107Memory controllers allow for several csrows, with 8 csrows being a typical value.
@@ -131,7 +131,7 @@ for memory DIMMs:
131 DIMM_B1 131 DIMM_B1
132 132
133Labels for these slots are usually silk screened on the motherboard. Slots 133Labels for these slots are usually silk screened on the motherboard. Slots
134labeled 'A' are channel 0 in this example. Slots labled 'B' 134labeled 'A' are channel 0 in this example. Slots labeled 'B'
135are channel 1. Notice that there are two csrows possible on a 135are channel 1. Notice that there are two csrows possible on a
136physical DIMM. These csrows are allocated their csrow assignment 136physical DIMM. These csrows are allocated their csrow assignment
137based on the slot into which the memory DIMM is placed. Thus, when 1 DIMM 137based on the slot into which the memory DIMM is placed. Thus, when 1 DIMM
@@ -140,7 +140,7 @@ is placed in each Channel, the csrows cross both DIMMs.
140Memory DIMMs come single or dual "ranked". A rank is a populated csrow. 140Memory DIMMs come single or dual "ranked". A rank is a populated csrow.
141Thus, 2 single ranked DIMMs, placed in slots DIMM_A0 and DIMM_B0 above 141Thus, 2 single ranked DIMMs, placed in slots DIMM_A0 and DIMM_B0 above
142will have 1 csrow, csrow0. csrow1 will be empty. On the other hand, 142will have 1 csrow, csrow0. csrow1 will be empty. On the other hand,
143when 2 dual ranked DIMMs are similiaryly placed, then both csrow0 and 143when 2 dual ranked DIMMs are similarly placed, then both csrow0 and
144csrow1 will be populated. The pattern repeats itself for csrow2 and 144csrow1 will be populated. The pattern repeats itself for csrow2 and
145csrow3. 145csrow3.
146 146
@@ -246,7 +246,7 @@ Module Version read-only attribute file:
246 246
247 'mc_version' 247 'mc_version'
248 248
249 The EDAC CORE modules's version and compile date are shown here to 249 The EDAC CORE module's version and compile date are shown here to
250 indicate what EDAC is running. 250 indicate what EDAC is running.
251 251
252 252
@@ -423,7 +423,7 @@ Total memory managed by this csrow attribute file:
423 'size_mb' 423 'size_mb'
424 424
425 This attribute file displays, in count of megabytes, of memory 425 This attribute file displays, in count of megabytes, of memory
426 that this csrow contatins. 426 that this csrow contains.
427 427
428 428
429Memory Type attribute file: 429Memory Type attribute file:
@@ -557,7 +557,7 @@ On Header Type 00 devices the primary status is looked at
557for any parity error regardless of whether Parity is enabled on the 557for any parity error regardless of whether Parity is enabled on the
558device. (The spec indicates parity is generated in some cases). 558device. (The spec indicates parity is generated in some cases).
559On Header Type 01 bridges, the secondary status register is also 559On Header Type 01 bridges, the secondary status register is also
560looked at to see if parity ocurred on the bus on the other side of 560looked at to see if parity occurred on the bus on the other side of
561the bridge. 561the bridge.
562 562
563 563
@@ -588,7 +588,7 @@ Panic on PCI PARITY Error:
588 'panic_on_pci_parity' 588 'panic_on_pci_parity'
589 589
590 590
591 This control files enables or disables panic'ing when a parity 591 This control files enables or disables panicking when a parity
592 error has been detected. 592 error has been detected.
593 593
594 594
@@ -616,12 +616,12 @@ PCI Device Whitelist:
616 616
617 This control file allows for an explicit list of PCI devices to be 617 This control file allows for an explicit list of PCI devices to be
618 scanned for parity errors. Only devices found on this list will 618 scanned for parity errors. Only devices found on this list will
619 be examined. The list is a line of hexadecimel VENDOR and DEVICE 619 be examined. The list is a line of hexadecimal VENDOR and DEVICE
620 ID tuples: 620 ID tuples:
621 621
622 1022:7450,1434:16a6 622 1022:7450,1434:16a6
623 623
624 One or more can be inserted, seperated by a comma. 624 One or more can be inserted, separated by a comma.
625 625
626 To write the above list doing the following as one command line: 626 To write the above list doing the following as one command line:
627 627
@@ -639,11 +639,11 @@ PCI Device Blacklist:
639 639
640 This control file allows for a list of PCI devices to be 640 This control file allows for a list of PCI devices to be
641 skipped for scanning. 641 skipped for scanning.
642 The list is a line of hexadecimel VENDOR and DEVICE ID tuples: 642 The list is a line of hexadecimal VENDOR and DEVICE ID tuples:
643 643
644 1022:7450,1434:16a6 644 1022:7450,1434:16a6
645 645
646 One or more can be inserted, seperated by a comma. 646 One or more can be inserted, separated by a comma.
647 647
648 To write the above list doing the following as one command line: 648 To write the above list doing the following as one command line:
649 649
@@ -651,14 +651,14 @@ PCI Device Blacklist:
651 > /sys/devices/system/edac/pci/pci_parity_blacklist 651 > /sys/devices/system/edac/pci/pci_parity_blacklist
652 652
653 653
654 To display what the whitelist current contatins, 654 To display what the whitelist currently contains,
655 simply 'cat' the same file. 655 simply 'cat' the same file.
656 656
657======================================================================= 657=======================================================================
658 658
659PCI Vendor and Devices IDs can be obtained with the lspci command. Using 659PCI Vendor and Devices IDs can be obtained with the lspci command. Using
660the -n option lspci will display the vendor and device IDs. The system 660the -n option lspci will display the vendor and device IDs. The system
661adminstrator will have to determine which devices should be scanned or 661administrator will have to determine which devices should be scanned or
662skipped. 662skipped.
663 663
664 664
@@ -669,5 +669,5 @@ Turn OFF a whitelist by an empty echo command:
669 669
670 echo > /sys/devices/system/edac/pci/pci_parity_whitelist 670 echo > /sys/devices/system/edac/pci/pci_parity_whitelist
671 671
672and any previous blacklist will be utililzed. 672and any previous blacklist will be utilized.
673 673