ECE 441 · Week 1
Modern Computer: Secure Infrastructure
Public SoC sections a student may rely on, and questions those documents do not answer.
Week 1 of 10 · Solitude
ECE 441 · Week 1
The board: Solitude
- 5 V
- 3.3 V
- Ground
- I2C
- SPI
- UART
- PWM
- TDM
- PDM
- Console TX
- Console RX
- Console ground
Colours as on the Solitude pinout, where each pin's name is. The square pad is pin 1.
ECE 441 · Week 1 · In class
Public SoC sections a student may rely on, and questions those documents do not answer.
- Check a claim only against the running board.
- A section goes in the first column when you can point at the same fact on the board.
- A question the document does not answer stays in the second column.
- A section you will not rely on stays off the graded table.
ECE 441 · Week 1 · In class
The homework is one public section the lecture says a student may not treat as a register list, and why.
- Use a section title from the documents in front of you.
- These notes do not print a second table of section numbers.
ECE 441 · Week 1 · Lecture
What "secure" means in this course
- A stack you understand: every stage tied to a document you can read.
- A stack you can check: every claim matched against the running board.
- A stack you can rebuild: the same source gives the same bytes.
- Nothing on the board is taken on trust, including a document.
ECE 441 · Week 1 · Lecture
Public documents and what they are for
| Document | Good for |
|---|---|
| Chip datasheet | Features, pins, electrical limits |
| Reference manual sections | How a block behaves, when published |
| Board schematic | What is wired to what on this board |
| Open source trees | What the software actually assumes |
Public documents are on the resources page.
ECE 441 · Week 1 · Lecture
Checking a claim against the board
cat /proc/cpuinfo
lscpu
tr '\0' '\n' < /proc/device-tree/compatible
cat /proc/device-tree/model; echo
ls /sys/devices/system/cpu/cpu0/cpufreq/- If the document says it and the board shows it, it goes in the first column.
- If the board cannot show it, the claim waits, however official it looks.
ECE 441 · Week 1 · Lecture
Questions the documents do not answer
- The software on the board may set a block up differently from the document's default.
- A document can be silent on a revision, a default, or a limit the board ships with.
- Write the question down exactly; an unanswered question is a result, not a failure.
- Do not fill a gap with a guess from another chip's manual.
ECE 441 · Week 1 · Lab
Lab
- From public SoC documents only, list the sections a student may rely on and the questions those documents do not answer.
- Check each claim against the running board. Second pass: add one section you will not rely on, then leave it off the graded table.
- Assemble the lab hand-in: A table of public SoC document sections: what a student may rely on, and what the document does not say.
ECE 441 · Week 1 · Lab
Hand in
A table of public SoC document sections: what a student may rely on, and what the document does not say.
ECE 441 · Week 1 · Homework
Homework
- Pick one public section the lecture says a student may not treat as a register list, and write why.
ECE 441 · Week 1 · Homework
Turn in
The section title and that reason.
ECE 441 · Week 1 · Read
Read
On the lab site: the resources page lists public documents and schematics. The modules do not grade this table. This week does.
ECE 441 · Week 1 · Next
Week 2
Each boot stage needs one log line and one public paragraph.