On Tue, Mar 13, 2018 at 11:36:25AM -0400, Stephen Douthit wrote: > On 03/13/2018 10:40 AM, Stefan Berger wrote: > > I think that should be a first test, maybe also for CRB. > > I don't think we can make that the first test. If we don't wait for > tpmRegValidSts (qualified by some known zero bit), then we can't tell > the difference between no-TPM, and reading before the device is ready. > > Note 2 in section 6.6 of the TIS 1.3 spec: > > 2. Within 30 milliseconds of the completion of TPM_Init: > a. All fields within the access register and all other registers MUST > return with the state of all their fields valid (i.e. > TPM_ACCESS_x.tpmRegValidSts is set to ‘1’). > b. The TPM MUST be ready to receive a command
I'm not sure of the specifics with the TPM. But, as a general rule of thumb, the SeaBIOS code can assume it's been over 30ms since power was turned on to the machine. -Kevin _______________________________________________ SeaBIOS mailing list [email protected] https://mail.coreboot.org/mailman/listinfo/seabios
