You are probably referring to NXP (formerly Philips) and Infineon (formerly Siemens), both of which have produced crypto processors, smartcards (including SIMs) and other secure elements for a really long time. Infineon is/was actually a really common supplier for the little 20-pin TPM/LPC modules.

Yes i think you're right. The nexus of sim, smart card and tpm seems strong. I e used thales and Luna (now also thales) HSM which are in hypothesis glamorous, but ultimately remarkably pedestrian secure devices. I wonder if they include logic from these companies. Supply chain behind FIPS120 class stuff would be an interesting story.