[net-next,v4,0/5,pull,request] add v2 FW logging for ice driver

Message

Tony Nguyen Oct. 5, 2023, 5:01 p.m. UTC

Paul Stillwell says:

Firmware (FW) log support was added to the ice driver, but that version is
no longer supported. There is a newer version of FW logging (v2) that
adds more control knobs to get the exact data out of the FW
for debugging.

The interface for FW logging is debugfs. This was chosen based on a
discussion here:
https://lore.kernel.org/netdev/[e-mail]/
We talked about using devlink in a variety of ways, but none of those
options made any sense for the way the FW reports data. We briefly talked
about using ethtool, but that seemed to go by the wayside. Ultimately it
seems like using debugfs is the way to go so re-implement the code to use
that.

FW logging is across all the PFs on the device so restrict the commands to
only PF0.

If FW logging is supported then a directory named 'fwlog' will be created
under '/sys/kernel/debug/ice/<pci_dev>'. A variety of files will be created
to manage the behavior of logging. The following files will be created:
- modules
- resolution
- enable
- nr_buffs
- data

where modules is used to read/write the configuration for FW logging

resolution is used to determine how often to send FW logging events to the
driver

enable is used to start/stop FW logging. This is a boolean value so only 1
or 0 are permissible values

nr_buffs is used to configure the number of data buffers the driver uses
for log data

data is used to read/clear the log data

Generally there is a lot of data and dumping that data to syslog will
result in a loss of data. This causes problems when decoding the data and
the user doesn't know that data is missing until later. Instead of dumping
the FW log output to syslog use debugfs. This ensures that all the data the
driver has gets retrieved correctly.

The FW log data is binary data that the FW team decodes to determine what
happened in firmware. The binary blob is sent to Intel for decoding.
---
v4: 
- removed CONFIG_DEBUG_FS wrapper around code because the debugfs calls handle
  this case already
- moved ice_debugfs_exit() call to remove unreachable code issue
- minor changes to documentation based on feedback

v3: https://lore.kernel.org/netdev/[e-mail]/
- Adjust error path cleanup in ice_module_init() for unreachable code.

v2: https://lore.kernel.org/netdev/[e-mail]/
- Rewrote code to use debugfs instead of devlink

v1: https://lore.kernel.org/netdev/[e-mail]/

Previous discussion:
https://lore.kernel.org/netdev/[e-mail]/

The following are changes since commit 49e7265fd098fdade2bbdd9331e6b914cda7fa83:
  net_sched: sch_fq: add TCA_FQ_WEIGHTS attribute
and are available in the git repository at:
  git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/next-queue 100GbE

Paul M Stillwell Jr (5):
  ice: remove FW logging code
  ice: configure FW logging
  ice: enable FW logging
  ice: add ability to read FW log data and configure the number of log
    buffers
  ice: add documentation for FW logging

 .../device_drivers/ethernet/intel/ice.rst     | 117 +++
 drivers/net/ethernet/intel/ice/Makefile       |   4 +-
 drivers/net/ethernet/intel/ice/ice.h          |   7 +
 .../net/ethernet/intel/ice/ice_adminq_cmd.h   | 161 ++--
 drivers/net/ethernet/intel/ice/ice_common.c   | 219 +----
 drivers/net/ethernet/intel/ice/ice_common.h   |   1 -
 drivers/net/ethernet/intel/ice/ice_debugfs.c  | 807 ++++++++++++++++++
 drivers/net/ethernet/intel/ice/ice_fwlog.c    | 450 ++++++++++
 drivers/net/ethernet/intel/ice/ice_fwlog.h    |  78 ++
 drivers/net/ethernet/intel/ice/ice_main.c     |  51 +-
 drivers/net/ethernet/intel/ice/ice_type.h     |  23 +-
 11 files changed, 1603 insertions(+), 315 deletions(-)
 create mode 100644 drivers/net/ethernet/intel/ice/ice_debugfs.c
 create mode 100644 drivers/net/ethernet/intel/ice/ice_fwlog.c
 create mode 100644 drivers/net/ethernet/intel/ice/ice_fwlog.h