Hi Ilias,
On Wed, 10 May 2023 at 01:44, Ilias Apalodimas ilias.apalodimas@linaro.org wrote:
For a TPM device to be operational we need to initialize it and perform its startup sequence. The 'tpm init' command currently calls tpm_init() which ends up calling the ->open() per-device callback and performs the initial hardware configuration as well as requesting locality 0 for the caller. We recently added tpm_auto_start() though, which automates the initialization process -- On top of that calling tpm_init() on selftests is a bit problematic, since calling it twice will return -EBUSY the second time although there is no actual problem with the TPM or the software stack.
So let's wire up the 'tpm init' command and call tpm_auto_start() which leaves the device in an operational state.
It's worth noting that calling tpm_init() only, doesn't allow a someone to use the TPM since the startup sequence is mandatory. We keep repeating the pattern of calling
- tpm_init
- tpm_startup
- tpm_self_test_full or tpm_continue_self_test
So we don't expect any regression or boot delays with the current change.
While at it fix the identation of test_tpm_autostart() comments as well
Signed-off-by: Ilias Apalodimas ilias.apalodimas@linaro.org
cmd/tpm-common.c | 3 ++- test/dm/tpm.c | 9 +++++---- 2 files changed, 7 insertions(+), 5 deletions(-)
We've been through this before. I do understand that EFI just does everything in U-Boot proper, but it is better for previous phases to set up the TPM, e.g. VPL, as we discussed on irc. In that case we cannot init the TPM twice.
I think what you want is a new 'tpm autostart' command, or something like that? You already have the tpm_auto_start() function so you can call that as needed.
Regards, Simon