Right SFP EEPROM config for DFP-34X-2C2 to work automatically work at 2500base-X?

[Headcrabed]

Edit: This procedure also works for ODI DFP-34X-2I3, more details here

Seems ODI has wrong configuration in DFP-34X-2C2's eeprom. And this blocks linux to use 2500base-X by default.

First, they set BR, Nominal value to 1300MBd, while it should be 3125MBd(Since 3125 cannot be set, it should be round off to 3100MBd).

Second, 1000base-LX is enabled by default, so that linux would prefer that speed (https://github.com/torvalds/linux/blob/cf1182944c7cc9f1c21a8a44e0d29abe12527412/drivers/net/phy/sfp-bus.c#L327)

After disabling 1000base-LX and set BR, Nominal value to 3100MBd in EEPROM, my device (Banana pi BPI-R3 + Openwrt 23.05.2) would use 2500base-X by default now.

For example:

Set addr 0x06 to 0x00(Disable 1000base-LX), addr 0x0c to 0x1f(3100MBd), addr 0x3f to 0x80(Checksum)

When using openwrt, you need to install ethtool-full and i2c-tools before operating. To dump eeprom, you can use ethtool -m *your sfp port here* raw on > dump.bin, then download the bin using winscp or something and open it using SFPTotal Wizard(It is used to calculate checksum, you can use other software instead)

[Anime4000]

to change this, do you use SFPTotal Whistle or Mini ?

[Anime4000]

based on this change:
torvalds/linux@466b97b
it committed on Nov 17, 2023

code change before if (bitmap_empty(modes, __ETHTOOL_LINK_MODE_MASK_NBITS) && br_nom) should give same results?

[Headcrabed]

I think it should behave the same before and after the commit you mentioned

[Anime4000]

@Headcrabed accroding to SFF-8472, at Addr 0x0a (Index 10) can identify fiber speed, I saw many DAC cable and 10G RJ45 SFP has this value filled 0x67 (0110 0111),

if this stick set to 0x05 (0000 0101) like this, OpenWRT will auto nego as well?

Addr	Value
0x06	0x00
0x0a	0x05
0x0c	0x1f

[Headcrabed]

@Headcrabed accroding to SFF-8472, at Addr 0x0a (Index 10) can identify fiber speed, I saw many DAC cable and 10G RJ45 SFP has this value filled 0x67 (0110 0111),

if this stick set to 0x05 (0000 0101) like this, OpenWRT will auto nego as well?
Addr Value
0x06 0x00
0x0a 0x05
0x0c 0x1f

I don't think so. That's a different speed mode, not 2.5gbps,

[Anime4000]

I see, I try play around that address LSB value, it did represent this:

there is another way to tell 2500Base-X ?

[duskyzaoKING]

Can you share the .bin of the entire firwmare with this modification ? will use a programer to flash direct in SOP

[Headcrabed]

Ok, I will do it later. But I still prefer you to do the modification by yourself, or you will lose your date code and serial number.

[duskyzaoKING]

Didnt thinked about it. I think its best i do. thanks

[Headcrabed]

dump_eeprom.zip
This is the dump of addr 0x50 of my eeprom

[lehoangnb]

I found this command can change EEPROM value, but eeprom content does not same as I read from chip using programer, anyone can check it work or not?
diag i2c set port 1 dev 0x50 reg 0x06 data 0x0
(For checksum, use diag i2c get port 1 dev 0x50 reg ... to dump all eeprom content from 0x00 to 0x3E and use SFPTotal to calculate)

[Anime4000]

I tried this, diag i2c wont write to it, I wonder if there easy way to write internally

[lehoangnb]

Yes, I think its is dummy eeprom, the value remain after reboot but doesn't same as real eeeprom
I have dump all value from i2c diag

[Anime4000]

I tried

Addr	Value
0x06	0x00
0x0c	0x1F

Mikrotik detect as this instance

The way Mikrotik show supported are different, I wonder what value to make 2.5G baseX in supported list

[Anime4000]

Checksum is good,
I talked to others indeed ROS' bug, what I test:
0x06 = 0x02 & 0x0c = 0x1f prints 10G baseSR LR together with 2.5G baseX
0x06 = 0x02 & 0x0c = 0x19 doesn't print 10G baseSR LR and 2.5G baseX
0x06 = 0x00 & 0x0c = 0x0d doesn't print 10G baseSR LR and 2.5G baseX

so, the Addr 0x0c >= 0x1f (>=3100) make ROS think is a 10G baseSR LR

[vuducdong]

Checksum is good, I talked to others indeed ROS' bug, what I test: 0x06 = 0x02 & 0x0c = 0x1f prints 10G baseSR LR 0x06 = 0x02 & 0x0c = 0x19 doesn't print 10G baseSR LR 0x06 = 0x00 & 0x0c = 0x0d doesn't print 10G baseSR LR

so, the Addr 0x0c >= 0x1f (>=3100) make ROS think is a 10G baseSR LR

Please send report it to Mikrotik technical support.

[Anime4000]

Checksum is good, I talked to others indeed ROS' bug, what I test: 0x06 = 0x02 & 0x0c = 0x1f prints 10G baseSR LR 0x06 = 0x02 & 0x0c = 0x19 doesn't print 10G baseSR LR 0x06 = 0x00 & 0x0c = 0x0d doesn't print 10G baseSR LR
so, the Addr 0x0c >= 0x1f (>=3100) make ROS think is a 10G baseSR LR

Please send report it to Mikrotik technical support.

Forum or on this page?

[vuducdong]

Checksum is good, I talked to others indeed ROS' bug, what I test: 0x06 = 0x02 & 0x0c = 0x1f prints 10G baseSR LR 0x06 = 0x02 & 0x0c = 0x19 doesn't print 10G baseSR LR 0x06 = 0x00 & 0x0c = 0x0d doesn't print 10G baseSR LR

so, the Addr 0x0c >= 0x1f (>=3100) make ROS think is a 10G baseSR LR

Please send report it to Mikrotik technical support.

Forum or on this page?

Yes, this page

[Anime4000]

Alright, I need to craft the support and detailed documentation, I use MA5671a EEPROM instead since can be edit via SSH

[ifplusor]

I test this on Banana Pi BPI-R4, it's work.

[Hannabiann]

How to flashing modified firmware? Only programmer?

[Headcrabed]

Please check the discussion on 1st reply