Hi, > just an update, I enabled the debug prints and I saw two timeouts fired > with a lot > of time lost (~780ms between "init timer" and "Scan for VGA ..."), > putting other prints I discovered that a lot of time is spent in the > tpm_setup(), > during the probe of the 2 TPM devices: > > 00.548869 init timer > 00.549677 ./src/post.c:157 platform_hardware_setup > 00.550182 ./src/hw/tpm_drivers.c:579 tpmhw_probe > 01.300833 WARNING - Timeout at wait_reg8:81! > 01.301388 ./src/hw/tpm_drivers.c:579 tpmhw_probe > 01.331843 WARNING - Timeout at wait_reg8:81! > 01.332316 ./src/post.c:160 platform_hardware_setup > 01.333358 Scan for VGA option rom > > Indeed, in the probe of the TPM devices (TIS and CRB) there are timeouts of > 750 ms and 30 ms respectively. > > Then, statically disabling TPM and TCG (CONFIG_TCGBIOS) the time spent > in SeaBIOS goes down from ~846ms to ~56ms: > # SeaBIOS disabling CONFIG_TCGBIOS > BIOS=/home/stefano/repos/seabios/out_notcgbios/bios.bin > qemu_init_end: 40.658371 > fw_start: 40.850395 (+0.192024) > fw_do_boot: 96.750142 (+55.899747) > linux_start_boot: 98.880578 (+2.130436) > > The tpm_setup() is called after the qemu_cfg_init(), so I think we can > disable > this call using some fw_cfg parameters, if we will decide to implement a > runtime > approach.
Another possible option is to simply use shorter timeouts on qemu (using runningOnQEMU()), I'd suggest to check with the TPM maintainers whenever that is ok. Background: The drivers in seabios work on both virtual and physical hardware (you can run seabios as coreboot payload on physical hardware). There are quite a few places where are delays and timeouts which are required to work properly on physical hardware. But typically virtual hardware is alot faster. There is -- for example -- no time needed to establish a sata link. Link detection in ahci is instant on qemu. cheers, Gerd
