Hi Alan,
I can answer this from the PSA Firmware Framework specification point of view, Ken (or others in the TF-M team) can clarify how closely the TF-M behaviour matches this.
In the manifest each service has a "signal" attribute which is a C identifier that is given the signal value for that service. The value is allocated by the TF-M tools and should be available to the SP source code via a generated header file - the specification places these definitions in the psa_manifest/<manifestfilename>.h header file, matching the name of the manifest file itself.
When the SP receives a set of signals from psa_wait(), it can identify which signals are asserted using these identifiers to test the signal bits.
The example RoT Service in Appendix D of the PSA Firmware Framework demonstrates this.
Regards, Andrew
-----Original Message----- From: TF-M tf-m-bounces@lists.trustedfirmware.org On Behalf Of DeMars, Alan via TF-M Sent: 08 March 2019 13:52 To: tf-m@lists.trustedfirmware.org Subject: [TF-M] multiple services within the same SP
In a multi-service SP, how does the SP know which SID has been used to connect to it? -- TF-M mailing list TF-M@lists.trustedfirmware.org https://lists.trustedfirmware.org/mailman/listinfo/tf-m IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
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