Reference clock register setting when use ENET_REF_CLK in RGMII

[ko-hey]

Hi all

I want to confirm register setting when use ENET_REF_CLK in RGMII.

I'll use i.MX6Q and input 125 MHz from the external crystal to ENET_REF_CLK (V 22) for use ethernet as RGMII.

Could you confirm the register setting in above case ?

Q1.

Are the following four registers only required to be set ?
Please let me know if it is added.

IOMUXC_SW_MUX_CTL_PAD_ENET_REF_CLK
IOMUXC_ENET_REF_CLK_SELECT_INPUT
IOMUXC_SW_MUX_CTL_PAD_RGMII_TX_CTL
IOMUXC_SW_PAD_CTL_PAD_ENET_REF_CLK

Q2.

Please tell me the following settings are correct.

Q2-1: [IOMUXC_SW_MUX_CTL_PAD_ENET_REF_CLK]

SION = 0 (Disable)
MUX_MODE = 001 (ALT1)

Q2-2: [IOMUXC_ENET_REF_CLK_SELECT_INPUT]

DAISY = 0 (RGMII_TX_CTL_ALT7)

Q2-3: [IOMUXC_SW_MUX_CTL_PAD_RGMII_TX_CTL]

SION = 0 (Disable)
MUX_MODE = 111 (ALT7)

Q2-4: [IOMUXC_SW_PAD_CTL_PAD_ENET_REF_CLK]

Depends on user.

Ko-hey

[Yuri · Accepted solution]

Hello,

Q2-1 and Q2-4 are correct.

Q2-2 and Q2-3 relate to other pin : RGMII_TX_CTL (C23)

IOMUXC_ENET_REF_CLK_SELECT_INPUT

and

IOMUXC_SW_MUX_CTL_PAD_RGMII_TX_CTL

configure RGMII_TX_CTL (C23) pin.

  Note, Pin tools may be useful :

Pins Tool for i.MX Application Processors|NXP 

Have a great day,

Yuri

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[ko-hey]

Hi Yuri

I understand we have to set only IOMUXC_SW_MUX_CTL_PAD_ENET_REF_CLK and IOMUXC_SW_PAD_CTL_PAD_ENET_REF_CLK register for use ENET_REF_CLK.

Thank you.

Ko-hey