[TF-A] Re: Measured boot and external TPM modules

On 6/4/22 8:53 AM, Ramon Fried wrote:

Hi Stuart, The problem with implementing a driver for a specific TPM in BL1 is that you're stuck with that specific 3rd party TPM for life (or until the next tapeout). I would like to minimize the 3rd party drivers (outside the SOC) in BL1.

With the interface I described you shouldn't need any vendor specific TPM driver in BL1. The locations of the TPM_HASH_START/DATA/END registers are standard. BL1 simply needs to be able access the TPM via the SPI or I2C bus.

Stuart