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[DOC] Update I3C integration specifications regarding PID and DCR registers #1023

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[DOC] Update I3C integration specifications regarding PID and DCR registers #1023

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Update I3C integration specifications regarding PID and DCR registers
clayton8 Jan 16, 2026
90f940b
Update docs/CaliptraSSIntegrationSpecification.md
clayton8 Jan 16, 2026
ac57296
Update I3C configuration recommendations
clayton8 Jan 16, 2026
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4 changes: 4 additions & 0 deletions docs/CaliptraSSIntegrationSpecification.md
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Expand Up @@ -2423,6 +2423,10 @@ The I3C core can be configured as an [AXI Recovery interface](CaliptraSSHardware
3. Follow the programming sequence described in [Programming Sequence from AXI Side](#programming-sequence-from-axi-side) **Point#2** to set both I3C target device with static addresses. **Note**, this is not required if I3C Host device is using the CCC `ENTDAA` for initializing the dynamic address to both targets.
4. If no external I3C connect `cptra_ss_i3c_recovery_image_activated_o` directly to `cptra_ss_i3c_recovery_image_activated_i`. If there is an external I3C `cptra_ss_i3c_recovery_image_activated_o` can be combined with or completely replaced with SOC logic and connected to `cptra_ss_i3c_recovery_image_activated_i`.
5. If no external I3C connect `cptra_ss_i3c_recovery_payload_available_o` directly to `cptra_ss_i3c_recovery_payload_available_i`. If there is an external I3C `cptra_ss_i3c_recovery_payload_available_o` can be combined with or completely replaced with SOC logic and connected to `cptra_ss_i3c_recovery_payload_available_i`.
6. It is the integrator’s responsibility to correctly set the I3C core’s PID and DCR registers to unique values to support I3C ENTDAA mode. If two devices on the bus share the same PID, DCR, and BCR values, ENTDAA will fail. Unique values can be assigned in one of two ways:
1. FW: Before enabling the I3C core, MCU FW can program these registers with the appropriate values for the device.
2. HW: Modify the I3C RDL and regenerate the I3C‑Core RDL collateral.
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7. The I3C static address is disabled on reset. If your design requires a static address before dynamic address assignment occurs, the MCU must program the static address as part of the I3C configuration flow.

Copilot AI Jan 16, 2026

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The line has a trailing space after "flow." which should be removed for consistency with markdown formatting best practices.

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7. The I3C static address is disabled on reset. If your design requires a static address before dynamic address assignment occurs, the MCU must program the static address as part of the I3C configuration flow.
7. The I3C static address is disabled on reset. If your design requires a static address before dynamic address assignment occurs, the MCU must program the static address as part of the I3C configuration flow.

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@calebofearth calebofearth Jan 16, 2026

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I do like to remove trailing whitespaces... but other than this change I'd approve the PR :)


## Programming Sequence

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