MemTest86+ multi-arch version

This is a MemTest86+ v5.1 refactored to support multiple hardware architectures.

DISCLAIMER: USE AT YOUR OWN RISK. DO NOT USE AT ALL ON REAL HARDWARE UNLESS YOU KNOW WHAT YOU ARE DOING.

WARNING: This is a Work-in-Progress yet, so be prepared to false-positives and false-negatives.

This repository includes the RISC-V port for my build of RocketChip for an FPGA board from AliExpress. This board has a regular DDR2-SODIMM slot, so testing memory can be not only a "model example".

While I was trying to parse FDT when possible instead of hardcoding memory map, there may still exist some "magic numbers". Especially, it does not handle reserved memory areas. I have none on my soft-processor but running such code on real-life CPU may probably cause some damage.

Usage

Build it with

make ARCH=riscv

In case some tools cannot be found (and this would probably be the case), edit arch/riscv/config.mk.

You will get

• memtest_shared -- an ELF shared object for use with GDB
• memtest_shared.bin -- a raw image to be loaded into memory
• memtest.uboot -- an U-Boot image pretending to be Linux kernel

For my board, boot command looks like this

run mmcsetup; run fdtsetup; fdt set /chosen bootargs "console=ttyS0"; fatload mmc 0:1 82000000 memtest.uboot; bootm fdt; bootm 82000000 - ${fdtaddr}

For manual startup, place memtest_shared.bin anywhere into your board RAM. Set registers as follows:

• $pc -- the load address of memtest_shared.bin
• $a0 -- hart id. Not used for now (SMP is NOT yet supported) but just for compatibility with other boot protocols
• $a1 -- load address of FDT, ask your bootloader for it :)
  • please note that the command line will be taken from /chosen/bootargs variable. Place something like console=ttyS0 there

Other info

See original README for more details.

See README.source-layout.md if you would like to implement another port.

License: GPL 2.

TODO

• Move all platform-specific code to arch/
• Make RISC-V port SMP-aware. Now it does not support SMP and may even malfunction in multi-core setups.
• Implement more information fetching from the RISC-V hardware and support for non-SiFive UART, RTC, etc. when needed