E3650 Bootloader

This repository contains the standalone simple_bootloader project for the E3650 platform.

It provides a minimal CR52 boot flow for E3650 that:

• Initializes the basic platform state, including clocks, reset signals, pinmux, optional MPU setup, and MRAM access
• Brings up the debug console on UART15 and also enables additional debug output on UART18 and UART19
• Reads the application boot package table (BPT) from MRAM flash
• Validates and loads the target CR52P0 image from the BPT
• Obtains the application entry point and remaps the CR52 cores to start the loaded image
• Produces .bin and .pac boot artifacts for deployment with the SemiDrive image generation flow

The official SSDK provides multiple build environments, including IAR and GHS. This repository currently keeps and maintains the GCC build flow only, so the project-specific build files are placed under GCC/.

Project layout:

• main.c
• configs/
• board/
• common/
• GCC/

Supported debug UARTs in the current configuration:

• UART15
• UART18
• UART19

Prerequisites

Required SSDK version: E3 SSDK PTG5.2 release

Linux:

• GNU Arm Embedded Toolchain with arm-none-eabi-gcc in PATH
• make
• bash
• Standard Unix utilities used by the build and PAC flow, including chmod, cp, mkdir, and rm
• Execute permission for the Linux image generation tools under $(SDK_ROOT)/tools/common/image_gen/builtin_tools/sdtools/linux/

Windows:

• GNU Arm Embedded Toolchain with arm-none-eabi-gcc in PATH
• mingw32-make.exe
• cmd.exe environment for running image_gen.bat
• A checkout of E3 SSDK PTG5.2 release available through SDK_ROOT
• SDToolBox_R2.25.1401 or later for the PTG5.2 release tool flow

Documentation and release packages:

• Documentation and images are distributed through the customer support system: http://support.semidrive.com/account/login
• Contact the SemiDrive marketing or product support team to request access permission

Source code and tools:

• E3 SSDK PTG5.2 release requires SDToolBox_R2.25.1401 or later
• The required tools can be obtained from the SemiDrive customer support system through the appropriate support contact

Build

From e3650_bootloader/GCC:

Windows:

mingw32-make.exe SDK_ROOT=D:/path/to/ssdk all pac

Linux:

make SDK_ROOT=/path/to/ssdk all pac

Outputs

• build/simple_bootloader.elf
• build/simple_bootloader.bin
• build/simple_bootloader.pac

Notes

• Windows PAC generation uses tools/common/image_gen/image_gen.bat.
• Linux PAC generation uses tools/common/image_gen/image_gen.sh.
• SDK_ROOT points to the external SSDK checkout that provides arch/, devices/, drivers/, middleware/, and tools/.
• The current Makefile and PAC generation flow were validated against E3 SSDK PTG5.2 release.
• The expected tool package version for this setup is SDToolBox_R2.25.1401 or later.
• The Linux path was validated with a Makefile dry-run in this workspace; Windows build and PAC generation were executed end-to-end.