PKA internal peripheral

Applicable for

1. Article purpose[edit source]

The purpose of this article is to:

briefly introduce the PKA peripheral and its main features
indicate the level of security supported by this hardware block
explain how it can be allocated to the three runtime contexts and linked to the corresponding software components
explain, when necessary, how to configure the PKA peripheral.

2. Peripheral overview[edit source]

The PKA (public key accelerator) is peripheral is used to ease computation of cryptographic public key primitives, specifically those related to RSA, Diffie-Hellmann or ECC (elliptic curve cryptography) over GF(p) (Galois fields).

2.1. Features[edit source]

Refer to the STM32MP13 reference manuals for the complete list of features, and to the software components, introduced below, to see which features are implemented.

2.2. Security support[edit source]

The PKA is a secure peripheral (under ETZPC control).

3. Peripheral usage and associated software[edit source]

3.1. Boot time[edit source]

PKA is a boot device that manage signature verification while a Flash programming with STM32CubeProgrammer, also while a boot from any device on a secured and closed device.

3.2. Runtime[edit source]

3.2.1. Overview[edit source]

PKA instance is allocated to:

the Arm^® Cortex^®-A7 secure core to be controlled in OP-TEE by the PKA OP-TEE driver through the ECC framework.

3.2.2. Software frameworks[edit source]

Internal peripherals software table template

| Security
| Peripheral (PKA internal peripheral)
| OP-TEE PKA driver
| 
| 
|
|-
|}

3.2.3. Peripheral configuration[edit source]

The configuration is applied by the firmware running in the context to which the peripheral is assigned. The configuration can be done alone via the STM32CubeMX tool for all internal peripherals, and then manually completed (particularly for external peripherals), according to the information given in the corresponding software framework article.

3.2.4. Peripheral assignment[edit source]

Internal peripherals assignment table template

| rowspan="2" | Security
| rowspan="2" | Peripheral (PKA internal peripheral)
| Instance1
| ☐
|☐
|
|
|-

|}