CC: linux-wireless, wifi chips used to have similar problem On Wed, 11 Jul 2018 13:42:57 +0300, Alex Vesker wrote: > This is a proposal which will allow access to driver defined address > regions using devlink. Each device can create its supported address > regions and register them. A device which exposes a region will allow > access to it using devlink. > > The suggested implementation will allow exposing regions to the user, > reading and dumping snapshots taken from different regions. > A snapshot represents a memory image of a region taken by the driver. > > If a device collects a snapshot of an address region it can be later > exposed using devlink region read or dump commands. > This functionality allows for future analyses on the snapshots to be > done. > > The major benefit of this support is not only to provide access to > internal address regions which were inaccessible to the user but also > to provide an additional way to debug complex error states using the > region snapshots. > > Implemented commands: > $ devlink region help > $ devlink region show [ DEV/REGION ] > $ devlink region del DEV/REGION snapshot SNAPSHOT_ID > $ devlink region dump DEV/REGION [ snapshot SNAPSHOT_ID ] > $ devlink region read DEV/REGION [ snapshot SNAPSHOT_ID ] > address ADDRESS length length You got me excited with the read without snapshot but then you say below that it's future work :) > Show all of the exposed regions with region sizes: > $ devlink region show > pci/0000:00:05.0/cr-space: size 1048576 snapshot [1 2] > pci/0000:00:05.0/fw-health: size 64 snapshot [1 2] > > Delete a snapshot using: > $ devlink region del pci/0000:00:05.0/cr-space snapshot 1 > > Dump a snapshot: > $ devlink region dump pci/0000:00:05.0/fw-health snapshot 1 > 0000000000000000 0014 95dc 0014 9514 0035 1670 0034 db30 > 0000000000000010 0000 0000 ffff ff04 0029 8c00 0028 8cc8 > 0000000000000020 0016 0bb8 0016 1720 0000 0000 c00f 3ffc > 0000000000000030 bada cce5 bada cce5 bada cce5 bada cce5 > > Read a specific part of a snapshot: > $ devlink region read pci/0000:00:05.0/fw-health snapshot 1 address 0 > length 16 > 0000000000000000 0014 95dc 0014 9514 0035 1670 0034 db30 > > For more information you can check devlink-region.8 man page > > Future: > There is a plan to extend the support to include a write command > as well as performing read and dump live region Reading live region would be very interesting and alleviate the need for complicated ethtool dump marshalling a number of drivers started doing (incl. nfp). Any plans on that? Write support I'm less excited about :)
