raspi-pacs

Peripheral access crates for the Broadcom microprocessors used in the Raspberry Pi boards.

This repository contains the scripts to generate the PACs for the following MCUs:

• BCM2835, found in the Raspberry Pi 1 and Zero
• BCM2837, found in the Raspberry Pi 3 and Zero 2W
• BCM2711, found in the Raspberry Pi 4

These PACs are generated by svd2rust from the SVD files in adafruit/broadcom-peripherals, save that patches are applied to add the missing tags required by svd2rust.

A Note on Virtual Memory

The PACs expect the memory-mapped registers of the peripherals to be present on their physical addresses; therefore, the PACs integrate poorly with virtual memory. If the register files are offset-mapped to a different base address, it is advised to generate the PACs by yourself from our patched SVD files and using the --base-address-shift option of svd2rust.

Feature Flags of the PACs

• atomic: Extends the register API with operations to atomically set, clear, and toggle specific bits.
• defmt: Include defmt::Format implementations.

Generating the PACs

Prerequisites for the PACs

• make
• patch
• Jinja2 CLI
• A Rust toolchain with cargo and rustfmt
• svd2rust (The latest version that works with our SVD files is 0.31.5.)
• form (≥ 0.11 is required for the generated PACs to be compilable on Windows.)

Also, the submodule broadcom-peripherals must be checked out.

Steps to Generate the PACs

To generate the PAC for a particular MCU, run:

make build/pacs/<mcu_name>-lpa

where <mcu_name> is one of bcm2835, bcm2837, or bcm2711. The generated PAC will be located in build/pacs/<mcu_name>-lpa. This step also generates the patched SVD file, which is located in build/svds/<mcu_name>.svd.

Or, to generate the PACs for all MCUs at once, run:

make pacs

Generating Just the SVD Files

Prerequisites for the SVD Files

• make
• patch

Also, the submodule broadcom-peripherals must be checked out.

Steps to Generate the SVD Files

To generate the SVD file for a particular MCU, run:

make build/svds/<mcu_name>.svd

where <mcu_name> is one of bcm2835, bcm2837, or bcm2711. The generated SVD file will be located in build/svds/<mcu_name>.svd.

Or, to generate the SVD files for all MCUs at once, run:

make svds