u-Boot changing ethernet speed with i.MX6

[_Anthony]

Hello,

I hope you're going well in this period,

I permit to contact you because I've got a question about how to change the ethernet connection flow from 100 to 1000 Mb/s in u-boot environment.

So Actually, I know the following commands permit to limit connexion flow to 100 Mb/s:

=> mdio write FEC 9 0
=> mdio write FEC 0 3300

But I would like to reverse the operation to limit connexion flow to 1000Mb/s.

The mmi dump command shows we're in 100Mb/s.

=> mii dump          
0.     (3100)                 -- PHY control register --
  (8000:0000) 0.15    =     0    reset
  (4000:0000) 0.14    =     0    loopback
  (2040:2000) 0. 6,13 =   b01    speed selection = 100 Mbps
  (1000:1000) 0.12    =     1    A/N enable
  (0800:0000) 0.11    =     0    power-down
  (0400:0000) 0.10    =     0    isolate
  (0200:0000) 0. 9    =     0    restart A/N
  (0100:0100) 0. 8    =     1    duplex = full
  (0080:0000) 0. 7    =     0    collision test enable
  (003f:0000) 0. 5- 0 =     0    (reserved)

Do you know how can I switch to 1000Mb/s mode? What are the mdio FEC commands?

Thanks for all and best reguards.

Anthony.

[igorpadykov · Accepted solution]

Hi Anthony

one can try to set bits 6,13 = b10 speed selection = 1000 Mbps
/* Basic mode control register. */
#define BMCR_SPEED1000 0x0040 /* MSB of Speed (1000)
#define BMCR_SPEED100 0x2000 /* Select 100Mbps 

https://source.codeaurora.org/external/imx/uboot-imx/tree/include/linux/mii.h?h=imx_v2020.04_5.4.70_...

Best regards
igor

[_Anthony]

Hello,

Thanks for your response.

So I success to do it with theses commands:

mdio write FEC 9 300

mdio write FEC 0 1340

Best reguards.