On Wed, Nov 07, 2012 at 04:23:14PM +0100, Mathias LEBLANC wrote: > Hi Kent, > > Sorry for sending new driver, it was a mistake. > Today, I will upload the new version of the Linux driver without the errors > that you have mentioned in your previous mail.
Ok, np. > > About : > > +/* > > + * tpm_st33_i2c_ioctl provides 2 handles: > > + * - TPMIOC_CANCEL: allow to CANCEL a TPM commands execution. > > + * See tpm_stm_i2c_cancel description above > > + * - TPMIOC_TRANSMIT: allow to transmit a TPM commands. > > + * - TPMIOC_HASH: allow to compute a locality 4 hash > > + * - TPMIOC_CHANGELOCALITY: allow to change the current locality > > Can we get rid of the ioctl path? cancel and transmit are available > through read/write already, but I need help understanding what hash and > change locality would be useful for. If the kernel is running you can > just use the crypto api for a hash operation, right? > > As for changing locality, what's the idea there? If you can just > switch localities at any time with an ioctl and no DRTM, why have it? > > [cut] > > +static const struct file_operations tpm_st33_i2c_fops = { > > + .owner = THIS_MODULE, > > + .llseek = no_llseek, > > + .read = tpm_read, > > + .write = tpm_write, > > + .open = tpm_open, > > + .release = tpm_release, > > +}; > > The TPM specification, specifies all four localities used for different levels > LOCALITY4_HASH by a CPU instruction to start > LOCALITY3 for BIOS > LOCALITY2 for MBR > LOCALITY1 for operation login > LOCALITY0 for common OS tasks. > > The use of these localities is agreement with the specifications and must > always be down (4, 3, 2, 1, 0) to be sure that the verification steps lower > levels will never be altered to ensure "sustainability". > If once the OS loaded, I am able to use the locality 4, I could potentially > alter the values of the starting steps below ... > Access to these localities in the driver * Linux * has been given only for > the purpose of validation. Ok cool, so it can be removed? :-) Kent > ________________________________________ > From: Kent Yoder [k...@linux.vnet.ibm.com] > Sent: 07 November 2012 16:02 > To: Mathias LEBLANC > Cc: Rajiv Andrade; Marcel Selhorst; Sirrix AG; > tpmdd-de...@lists.sourceforge.net; linux-kernel@vger.kernel.org; Jean-Luc > BLANC > Subject: Re: [PATCH 1/1] TPM: STMicroelectronics ST33 I2C > > On Wed, Nov 07, 2012 at 01:15:09PM +0100, Mathias Leblanc wrote: > > * STMicroelectronics version 1.2.0, Copyright (C) 2010 > > * STMicroelectronics comes with ABSOLUTELY NO WARRANTY. > > * This is free software, and you are welcome to redistribute it > > * under certain conditions. > > > > This is the driver for TPM chip from ST Microelectronics. > > > > If you have a TPM security chip from STMicroelectronics working with > > an I2C, in menuconfig or .config choose the tpm driver on > > device --> tpm and activate the protocol of your choice before compiling > > the kernel. > > The driver will be accessible from within Linux. > > > > Tested on linux x86/x64, beagleboard REV B & XM REV C and CHROMIUM OS > > > > Signed-off-by: Mathias Leblanc <mathias.lebl...@st.com> > > Hi Mathias, > > I didn't see a reply to my mail from Oct 31, and very little has > changed here. Did I miss something? > > Kent -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/