On Fri, Jul 14, 2023 at 9:19 AM Stefan Berger <stef...@linux.ibm.com> wrote: > > > > > I don't know whether we would want multiple devices. tpm_find() usage is > certainly not prepared for multiple devices. Sorry, "multiple TPM interfaces" here does not mean "at the same time". Will clarify the description.
> > > Good for the consolidation. > > > Does moving the TIS to a different address help on aarch64? That was the first thing we tried and no it doesn't help. > > Can the size really be an option? I don't see it useful and if one gave the > wrong size it may break things. It was added for consistency (otherwise we have to determine the size by looking at the interface everywhere). Also, it is possible for the size to be larger than the constant. For example, Apple Silicon uses 16KiB page sizes and we may decide to force the device to be 16KiB aligned (not sure if this is needed yet while we still track down why the dual mapping was not working). In that case, we would need to inform the OS of the true region size to prevent any overlap issues. Both baseaddr and size should be provided only by the plug handler in the virt machine, otherwise things may break even if we get rid of size and have just an incorrect baseaddr. > > >
