Re: [BUG] Nuvoton NCPT650 TPM 2.0 mode not working

From: Jarkko Sakkinen
Date: Mon Nov 19 2018 - 08:50:02 EST


On Sun, Nov 18, 2018 at 03:10:06PM +0100, Michael Niewöhner wrote:
> On Sun, 2018-11-18 at 10:18 +0200, Jarkko Sakkinen wrote:
> > On Fri, Nov 16, 2018 at 10:06:28PM +0100, Michael Niewöhner wrote:
> > > On Wed, 2018-11-14 at 21:46 +0100, Michael Niewöhner wrote:
> > > > Hi all,
> > > >
> > > > I tried that patch mentioned by Mimi but it does not change anything for
> > > > me.
> > > >
> > > > Then I did some more tests with different kernel configs and finally got
> > > > TPM
> > > > working by
> > > > a) compiling TPM as modules and rmmod tpm* and re-modprobe tpm_tis.
> > > >
> > > > (initramfs) dmesg | grep -i tpm
> > > > [ 0.000000] efi: ACPI 2.0=0x9ea7e000 ACPI=0x9ea7e000 SMBIOS=0x9f5eb000
> > > > SMBIOS 3.0=0x9f5ea000 ESRT=0x9c07d918 MEMATTR=0x9bea3018
> > > > TPMEventLog=0x97cbb018
> > > > [ 0.003793] ACPI: TPM2 0x000000009EAB7F70 000034 (v03 LENOVO TC-
> > > > S06 00001260 AMI 00000000)
> > > > (initramfs) rmmod tpm_crb tpm_tis tpm_tis_core tpm
> > > > (initramfs) modprobe tpm_tis
> > > > [ 44.956905] tpm_tis MSFT0101:00: 2.0 TPM (device-id 0xFE, rev-id 2)
> > > >
> > > > b) compiling TPM-support in-kernel and manually bind the ACPI device
> > > >
> > > > (initramfs) dmesg | grep -i tpm
> > > > [ 0.000000] efi: ACPI 2.0=0x9ea7e000 ACPI=0x9ea7e000 SMBIOS=0x9f5eb000
> > > > SMBIOS
> > > > 3.0=0x9f5ea000 ESRT=0x9c07d918 MEMATTR=0x9bea3018 TPMEventLog=0x97cbb018
> > > > [ 0.003546] ACPI: TPM2 0x000000009EAB7F70 000034 (v03 LENOVO TC-S06
> > > > 00001260
> > > > AMI 00000000)
> > > > (initramfs) echo MSFT0101:00 >/sys/bus/platform/drivers/tpm_tis/bind
> > > > [ 233.076079] tpm_tis MSFT0101:00: 2.0 TPM (device-id 0xFE, rev-id 2)
> > > >
> > > >
> > > > It seems to me, the kernel tries to enable the TPM to early...
> > > >
> > > >
> > > > Michael
> > >
> > > Looks like the manual driver bind works more or less but e.g reading hwrng
> > > does
> > > not work...
> > >
> > > # echo MSFT0101:00 >/sys/bus/platform/drivers/tpm_tis/bind
> > > [ 148.293302] tpm_tis MSFT0101:00: 2.0 TPM (device-id 0xFE, rev-id 2)
> > > # cat /sys/devices/virtual/misc/hw_random/rng_current
> > > tpm-rng-0
> > > # cat /dev/hwrng >/dev/null
> > > cat: /dev/hwrng: Operation not permitted
> >
> > Can you check with trace-cmd start -p function -l 'tpm*'?
> >
> > /Jarkko
>
>
> Hi Jarko,
>
> what output do you need exactly?

TPM gets added with tpm_add_hwrng() and the callback that is called by
hwrng subsystem is tpm_hwrng_read().

Obviously the former gets called (can be seen from the sysfs file). Just
wondering if it ever reaches tpm_hwrng_read().

/Jarkko