1@startuml
2skinparam ParticipantPadding 10
3skinparam BoxPadding 10
4box RSS
5participant RSS_BL1_1
6participant RSS_BL1_2
7participant RSS_BL2
8participant RSS_S
9endbox
10box SCP
11participant SCP_BL1
12endbox
13box AP
14participant AP_BL1
15participant AP_BL2
16participant AP_BL31
17endbox
18
19== RSS Boot phase ==
20-> RSS_BL1_1: Reset
21Rnote over RSS_BL1_1: ROM code, XIP
22Rnote over RSS_BL1_2: OTP code, XIP
23Rnote over RSS_BL2, AP_BL31: Stored in flash, loaded and executed in RAM
24activate RSS_BL1_1 #Green
25RSS_BL1_1 -->> RSS_BL1_2: Validate, measure
26Rnote over RSS_BL1_1: BL1_2 measurement\n\ saved to a shared buffer
27RSS_BL1_1 -> RSS_BL1_2: Pass execution
28deactivate RSS_BL1_1
29activate RSS_BL1_2 #Green
30RSS_BL1_2 -->> RSS_BL2: Validate, measure, load
31Rnote over RSS_BL1_2: RSS_BL2 measurement\n\ saved to a shared buffer
32RSS_BL1_2 -> RSS_BL2: Pass execution
33deactivate RSS_BL1_2
34activate RSS_BL2 #Green
35RSS_BL2 -->> RSS_S: Validate, measure, load
36RSS_BL2 -->> SCP_BL1: Validate, measure, load
37Rnote over RSS_BL2: RSS_S and SCP_BL1\n\ measurements saved\n\ to a shared buffer
38RSS_BL2 -> SCP_BL1: Release from reset
39activate SCP_BL1 #Green
40Rnote over RSS_BL2, SCP_BL1: MHU init between RSS and SCP
41Rnote over SCP_BL1: Configure memory
42Rnote over RSS_BL2: Waits for SCP
43SCP_BL1 --> RSS_BL2: Done
44RSS_BL2 -->> AP_BL1: Validate, measure, load
45Rnote over RSS_BL2: AP_BL1 measurement\n\ saved to a shared buffer
46RSS_BL2 -> AP_BL1: Release from reset
47activate AP_BL1 #Green
48RSS_BL2 -> RSS_S: Pass execution
49deactivate RSS_BL2
50activate RSS_S #Green
51Rnote over RSS_S: Measurements read from\n\ shared buffer and saved by\n\
52Measured Boot service to\n\ measurement slots.
53
54== RSS Runtime / AP Boot phase ==
55Rnote over RSS_S, AP_BL1: MHU init between RSS and AP
56Rnote over AP_BL1: Measure and load:\n\ FW_CONFIG\n\ TB_FW_CONFIG
57AP_BL1 -> RSS_S: Extend measurement
58Rnote over RSS_S: Measured Boot:\n\ store measurement
59AP_BL1 -->> AP_BL2: Validate, measure,load
60AP_BL1 -> RSS_S: Extend measurement
61Rnote over RSS_S: Measured Boot:\n\ store measurement
62AP_BL1 -> AP_BL2: Pass execution
63deactivate AP_BL1
64activate AP_BL2 #Green
65Rnote over AP_BL2: Measure and load:\n\ HW_CONFIG
66AP_BL2 -> RSS_S: Extend measurement
67Rnote over RSS_S: Measured Boot:\n\ store measurement
68AP_BL2 -->> AP_BL31: Validate, measure,load
69Rnote over AP_BL2: Measure and load:\n\ BL31
70AP_BL2 -> RSS_S: Extend measurement
71Rnote over RSS_S: Measured Boot:\n\ store measurement
72Rnote over AP_BL2: Measure and load:\n\ RMM
73AP_BL2 -> RSS_S: Extend measurement
74Rnote over RSS_S: Measured Boot:\n\ store measurement
75AP_BL2 -> AP_BL31: Pass execution
76deactivate AP_BL2
77activate AP_BL31 #Green
78== RSS / AP Runtime ==
79@enduml
80