README specifies subset of SPI chips seen in the wild

[tlaurion]

Just a trace.

Here are the SPI chips observed in the wild to address/verify coherent WP guarantees/statements in README and move doc in heads-wiki altogether hereafter, not having duplicate to maintain and be clear on instructions to build, access CIs and documentation access altogether.

Bottom SPI chips (3):
"EN25QH64" "N25Q064..3E" "MX25L6436E/MX25L6445E/MX25L6465E/MX25L6473E"

Top SPI chips (2):
"MX25L3273E" "N25Q032..3E"

[Thrilleratplay]

I think I found where there is a list of comparable chips in the Lenovo BIOS upgrade. For the x230, these are the steps I took:

wget https://download.lenovo.com/pccbbs/mobiles/g2uj33us.exe   
innoextract g2uj33us.exe 

cd app/G2ETB7WW/
binwalk -reM '$01D3000.FL1'
cd _\$01D3000.FL1.extracted 
uefitool 239

Search for text: "flashpartsmm"

EN25QH128FlashPartSmm.efi
EN25QH32FlashPartSmm.efi
EN25QH64FlashPartSmm.efi
MX25L3206EFlashPartSmm.efi
MX25L64XFlashPartSmm.efi
N25Q032FlashPartSmm.efi
N25Q064FlashPartSmm.efi
W25Q32FlashPartSmm.efi
W25Q64FlashPartSmm.efi

These names correspond to the following devices on the flashrom supported hardware page

EFI name	Vendor	Device	size in bytes
EN25QH128	Eon	EN25QH128	16384
EN25QH32	Eon	EN25QH32	4096
EN25QH64	Eon	EN25QH64	8192
MX25L3206E	Macronix	MX25L3206E - MX25L3206E/MX25L3208E	4096
MX25L64X	Macronix	MX25L6405,MX25L6405D, MX25L6406E/MX25L6408E, MX25L6436E/MX25L6445E/MX25L6465E/MX25L6473E/MX25L6473F, MX25L6495F	8192
N25Q032	Micron/Numonyx/ST	N25Q032..1E, N25Q032..3E	4096
N25Q064	Micron/Numonyx/ST	N25Q064..1E, N25Q064..3E	8192
W25Q32	Winbond	W25Q32.V, W25Q32.W	4096
W25Q64	Winbond	W25Q64.V, W25Q32.W	8192

The 16M chip is odd, maybe they used them in later versions?

[t-anon]

My x230 (non-T) has a cFeon QH64-104HIP, is this the same as the Eon EN25QH64?

[tlaurion]

@t-anon sorry for lack of update, unfortunately flashrom would tell.

It will provide a list of detected chips as per documentation. It has low impact on backup, where write function will differ.

As per doc, it is suggested to backup (-r) and verify (-v) backups prior flashing (-w)

If really doubtful, just take a couple of backups specifying different chips (-c) and compare those backups with sha256sum or whatever you feel like (*) to reduce anxiety.

And please update us!