Re: [tpmdd-devel] [PATCH] tpm: improve tpm_tis send() performance by ignoring burstcount

[Ken Goldman]

On 8/13/2017 7:53 PM, msuchanek wrote:
> About 500 out of 700 mainboards sold today has a PS/2 port which is
> probably due to prevalence of legacy devices and usbhid limitations.
>
> Similarily many boards have serial and parallel hardware ports.
>
> In all diagrams detailed enough to show these ports I have seen them
> attached to the LPC bus.

Do these boards have a TPM?  Remember that the TPM requires special LPC 
bus cycles.

Even if so, the TPM LPC bus wait states are less than a usec.  My 
thought is that  it's unlikely that any device (serial port, mouse, 
keyboard, printer) will be adversely affected.