Re: [PATCH v10 1/3] ipmi: ssif_bmc: Add SSIF BMC driver

[Quan Nguyen]

On 14/10/2022 20:05, Graeme Gregory wrote:
> On Mon, Oct 10, 2022 at 12:08:24PM +0100, Graeme Gregory wrote:
> > On 10/10/2022 02:28, Quan Nguyen wrote:
> > > On 07/10/2022 20:26, Graeme Gregory wrote:
> > > > On 04/10/2022 10:31, Quan Nguyen wrote:
> > > > > The SMBus system interface (SSIF) IPMI BMC driver can be used to
> > > > > perform
> > > > > in-band IPMI communication with their host in management (BMC) side.
> > > > >
> > > > > Thanks Dan for the copy_from_user() fix in the link below.
> > > > >
> > > > > Link: https://lore.kernel.org/linux-arm-kernel/20220310114119.13736-4-quan@xxxxxxxxxxxxxxxxxxxxxx/
> > > > > Signed-off-by: Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx>
> > > >
> > > > I have been testing this on our hardware and I don't seem to be able
> > > > to get this driver working. I was using an older version.
> > > >
> > > > I have hacked ssifbridged to deal with the change in len from u8 to
> > > > unsigned int.
> > > >
> > > > It works as long as I only ever send SSIF commands, any attempt to
> > > > read a response crashes the state machine and the driver never
> > > > recovers. No further SSIF comms is possible! (slave doesnt even ACK
> > > > writes).
> > > >
> > > > A couple of comments below on possible state machine errors.
> > > >
> > > > Its possible I am doing something wrong!
> > >
> > > Thanks Graeme for the test and the comments.
> > >
> > > What's your testing hardware?
> > >
> > > This was tested with Aspeed ast2500 and ast2600 with the patch series
> > > [1] below applied.
> > >
> > > If you use the same hw, could you pick the series and see if any thing
> > > improve ?
> > >
> > > [1] https://lore.kernel.org/all/20210616031046.2317-1-quan@xxxxxxxxxxxxxxxxxxxxxx/
> > Thanks, that patch series does stop the state machine crashing.
> >
> > I am testing on AST2600EVB with A1 rev, but we also have our own DC-SCM with
> > A3 chip.
> >
> > Responses are still not working for me, but I think that may be an error in
> > my ssifbridged hacks.
> >
> > Oct 10 10:54:55 qcom-evb-proto-ccf37d18ea0c ssifbridged[335]: Read ssif
> > request message with len=13 netfn=44 lun=0 cmd=2
> >
> > Oct 10 10:54:55 qcom-evb-proto-ccf37d18ea0c ipmid[312]: BootCode:
> > 000000000000000000
> >
> > Oct 10 10:54:55 qcom-evb-proto-ccf37d18ea0c ssifbridged[335]: Send ssif
> > respond message with len=4 netfn=45 lun=0 cmd=2 cc=0
> >
> > Oct 10 10:54:55 qcom-evb-proto-ccf37d18ea0c kernel: ipmi-ssif-host 0-0010:
> > Warn: on_read_requested_event unexpected READ REQUESTED in state=SSIF_READY
> >
> > Oct 10 10:54:55 qcom-evb-proto-ccf37d18ea0c kernel: ipmi-ssif-host 0-0010:
> > Warn: on_stop_event unexpected SLAVE STOP in state=SSIF_ABORTING
> Just to close the loop on this, I have now fully tested this driver on
> our setup internally.
>
> Final hitch turned out to be an aardvark not issuing STOP events between
> reads/writes.
>
> Thanks for the work.

Thanks a lot Graeme, for the test.

- Quan