linux-kernel - Re: [PATCH 0/2] tpm: add driver for cr50 on SPI

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20160715032814.GG9347@obsidianresearch.com>
Date:	Thu, 14 Jul 2016 21:28:14 -0600
From:	Jason Gunthorpe <jgunthorpe@...idianresearch.com>
To:	Andrey Pronin <apronin@...omium.org>
Cc:	Peter Huewe <peterhuewe@....de>,
	Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>,
	Marcel Selhorst <tpmdd@...horst.net>,
	tpmdd-devel@...ts.sourceforge.net, linux-kernel@...r.kernel.org,
	groeck@...omium.org, smbarber@...omium.org, dianders@...omium.org
Subject: Re: [PATCH 0/2] tpm: add driver for cr50 on SPI

On Thu, Jul 14, 2016 at 07:50:26PM -0700, Andrey Pronin wrote:
> Yes, it has a TCG-compliant interface, however, there are several things
> specific to this device:
>  - need to ensure a certain delay between spi transactions, or else
>    the chip can miss several first bytes.
>  - if there is no spi activity for this chip, it may go to sleep, and
>    needs to be waken up before sending further commands.
>  - it has some vendor-specific registers accessible from spi bus.

This all needs to be commented clearly in the driver..

The chip sounds pretty broken...

Jason