current position:Home>bios memory training

bios memory training

2022-11-24 22:06:12Han Xinwu

The function of bios is not only to fill in many registers, but also to do the work of memory training.

So, what is memory training?

Memory is the well-known ddr3, ddr4 and so on.

The definition of memory training is relatively esoteric. Simply put, it is to get a set of alignment, compensation and reference voltage parameters to balance and hedge the difference of the line and the noise of the signal.

As for why memory needs training, you can read this hardcore article

Why does the memory need Training? Why is the memory initialization code an alternative in the BIOS?- Zhihu (zhihu.com)

The memory initialization code is generally provided by the chip manufacturer, and Intel calls it MRC (memory reference code).

Memory training will only run when the motherboard runs the bios program for the first time, and the data after training will be stored in the bios and stored in fmap in coreboot.If you don't move the memory stick, you don't need to train the memory again.

If you pull out the memory stick at this time, it will be recorded by gpio, and you can start training again next time.

copyright notice
author[Han Xinwu],Please bring the original link to reprint, thank you.
https://en.cdmana.com/2022/328/202211242204384983.html

Random recommended