NXP i.MX 8X
The NXP i.MX 8X are embedded multi-core processors consisting of one Cortex-M4, up to two Cortex-A53 and one Tensilica HiFi 4 DSP.
Contents
External Boot Devices
Programming of external boot media(eMMC, SDHC, QSPI/NAND Flash) is supported natively through USB Serial interface.
Watchdog Handling
System controller firmware handles watchdog during boot and programming of boot devices.
Multi-Core Support
Before proceeding with this article, please check out the generic article regarding Multi-Core debugging here.
The i.MX 8X family comes with a variety of multi-core options listed in the following table:
Core | J-Link Support |
---|---|
4 x Cortex-A35 | |
1 x Cortex-M4F | |
1 x HIFI4 DSP |
The i.MX 8X family processors have additional cores:
- System Controller Unit (SCU) Cortex-M4 - responsible for system initialization and boot, power and resource management, pad configuration.
- Security Controller (SECO) Cortex-M0 - implements various security and cryptography functions.
In below, the debug related multi-core behavior of the J-Link is described for each core:
Cortex-A35 core(s)
Init/Setup
The core(s) are enabled by SCU after boot.
Reset
Core reset is performed by SCU.
Attach
Attach is supported.
Cortex-M4F core(s)
Init/Setup
The core(s) are enabled by SCU after boot.
Reset
Core reset is performed by SCU.
Attach
Attach is supported.
Device Specific Handling
Connect
A boot image should contain System Controller Unit (SCU) and Security Controller (SECO) firmware images. After the boot stage J-Link can be attached to a running target. By default only the main A35 core is enable, the other cores can be enabled by the bootloader or operating system kernel. In order to have read/write accesse to system memory, MMU should be configured accordingly.
Reset
J-Link does not support reset of particular cores, as it is controlled by SCU.