Re: [PATCH 2/2 v2] tpm_tis: override durations for STM tpm with firmware 1.2.8.28

From: Jarkko Sakkinen
Date: Thu Aug 29 2019 - 10:42:04 EST


On Thu, Aug 29, 2019 at 05:40:40PM +0300, Jarkko Sakkinen wrote:
> On Tue, Aug 27, 2019 at 05:46:21PM -0700, Jerry Snitselaar wrote:
> > There was revealed a bug in the STM TPM chipset used in Dell R415s.
> > Bug is observed so far only on chipset firmware 1.2.8.28
> > (1.2 TPM, device-id 0x0, rev-id 78). After some number of
> > operations chipset hangs and stays in inconsistent state:
> >
> > tpm_tis 00:09: Operation Timed out
> > tpm_tis 00:09: tpm_transmit: tpm_send: error -5
> >
> > Durations returned by the chip are the same like on other
> > firmware revisions but apparently with specifically 1.2.8.28 fw
> > durations should be reset to 2 minutes to enable tpm chip work
> > properly. No working way of updating firmware was found.
> >
> > This patch adds implementation of ->update_durations method
> > that matches only STM devices with specific firmware version.
> >
> > Cc: Peter Huewe <peterhuewe@xxxxxx>
> > Cc: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > Cc: Jason Gunthorpe <jgg@xxxxxxxx>
> > Signed-off-by: Alexey Klimov <aklimov@xxxxxxxxxx>
> > Signed-off-by: Jerry Snitselaar <jsnitsel@xxxxxxxxxx>
> > ---
> > v2: Make suggested changes from Jarkko
> > - change struct field name to durations from durs
> > - formatting cleanups
> > - turn into void function like update_timeouts and
> > use chip->duration_adjusted to track whether adjustment occurred.
>
> The code repetition looks horrible so I wrote a patch that should help:
>
> https://patchwork.kernel.org/patch/11121475/
>
> Read the remar that prepends the diffstat.

Forgot from that remark that I did not have TPM 1.x available at hand
(WFH today) so please also review and test it.

/Jrakko