# AMD eMMC 5.0 controller device driver



## sham1810 (Oct 16, 2018)

Hi,

I'm trying to port the following linux patch for AMD eMMC 5.0 controller:
https://patchwork.kernel.org/patch/10086747/

What would be the optimal way to port this? Should I create a separate module for this controller or is there a way I can override some of the host ops like its done in the patch?

I tried using quirks but it doesn't seem to work as needed. I am able to switch to HS400 mode but when I try loading mmcsd, I get a EXT_CSD timeout error.

HS400 mode log: https://pastebin.com/zAPDYcM3
MMCSD timeout Log Log: https://pastebin.com/hTTb3hhi
Patch: https://pastebin.com/YSrh0B4W

Update:

I was able to get HS400 mode selected.
MMCSD loads successfully now and I can see the partitions usins `gpart show`
However, when I ran iozone tests, there was no improvement in read/write performance. This makes me doubt whether HS400 is working or not. How can I be sure?


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## Samuel Venable (Nov 29, 2021)

Anyone have this patch actually published in a built FreeBSD img or installable driver, or instructions on how to get it working?


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