• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 33 subscribers
  • Views 190 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

DP83869HM: GEN_CFG1 Register: bit11 and bit12

Noriyuki Takahashi
Genius 11050 points
Part Number: DP83869HM
Other Parts Discussed in Thread: DP83869

Tool/software:

Hi team,

Customer understands that if 1000BASE-T mode is selected, PHYs can select Master and Slave via auto-negotiatin. And they also understand that the selection of Master and Slave can be set on manual using registers below.

GEN_CFG1 register

bit12: MASTER_SLAVE_MAN_CFG_EN

bit11: MASTER_SLAVE_MAN_CFG_VAL

So if they select Master and Slave on manual, they think they need to set bit12 and bit11. However, lookign at the driver in bleow link, only bit11 is set. Could you tell the reason why the driver set only bit11?

https://github.com/TexasInstruments/ti-ethernet-software/blob/main/linux_drivers/dp83869.c#L92

the below is the portion of the driver they mention.

/* CFG1 bits */#define DP83869_CFG1_DEFAULT             (ADVERTISE_1000HALF | \                                                    ADVERTISE_1000FULL | \                                                CTL1000_AS_MASTER)　　★#define CTL1000_AS_MASTER        0x0800　(this means that this driver sets only bit11: MASTER_SLAVE_MAN_CFG_VAL)

 

Regards,

Noriyuki Takahshi

  • 0
    TI__Mastermind 24998 points

    Hi Takahashi-san,

    Thank you for the query.

    I understand the concern here, please allow me some time to verify if 0x9[12] is required for manual master/slave configuration and update the driver accordingly.

    Is manual configuration required for customer's application? Master/slave resolution through auto-negotiation is expected to work without driver configuration.

    Thank you,

    Evan

  • 0 in reply to Evan Mayhew
    TI__Genius 11050 points

    Evan,

    Manual configuration is not required. 

    They just would like to confirm that they do not need to set bits 11 and 12 of the Gen_CFG1 register when they use the device with AutoNegotiation.

    Hopefully, they want the driver to be modified correctly.

    Regards,

    Noriyuki Takahashi

  • +1 in reply to Noriyuki Takahashi
    TI__Mastermind 24998 points

    Hi Takahashi,

    GEN_CFG1[12:11] are not required for using the device with auto-negotiation enabled, these bits only apply to manual master/slave configuration.

    Thank you,

    Evan