Data Sheet

Ethernet Controller I210 —Initialization
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The receive buffer size is controlled by RXPBSIZE.Rxpbsize register field. Refer to Section 4.5.9 for its
setting rules.
If DMA coalescing is enabled, to avoid packet loss, the FCRTC.RTH_Coal field should also be
programmed to a value equal to at least a single maximum packet size below the receive buffer size (a
value equal or less than FCRTH0.RTH + max size packet).
4.5.7 Link Setup Mechanisms and Control/Status Bit Summary
The CTRL_EXT.LINK_MODE value should be set to the desired mode prior to the setting of the other
fields in the link setup procedures.
4.5.7.1 PHY Initialization
Refer to the PHY documentation for the initialization and link setup steps. The software device driver
uses the MDIC register to initialize the PHY and setup the link. Section 3.7.4.4 describes the link setup
for the internal copper PHY. Section 3.7.2.2 Section describes the usage of the MDIC register.
4.5.7.2 MAC/PHY Link Setup (CTRL_EXT.LINK_MODE = 00b)
This section summarizes the various means of establishing proper MAC/PHY link setups, differences in
MAC CTRL register settings for each mechanism, and the relevant MAC status bits. The methods are
ordered in terms of preference (the first mechanism being the most preferred).
4.5.7.2.1 MAC Settings Automatically Based on Duplex and Speed Resolved by PHY
(CTRL.FRCDPLX = 0b, CTRL.FRCSPD = 0b,)
CTRL.FD Don't care; duplex setting is established from PHY's internal indication to the
MAC (FDX) after PHY has auto-negotiated a successful link-up.
CTRL.SLU Must be set to 1b by software to enable communications between MAC and PHY.
CTRL.RFCE Must be programmed by software after reading capabilities from PHY registers
and resolving the desired flow control setting.
CTRL.TFCE Must be programmed by software after reading capabilities from PHY registers
and resolving the desired flow control setting.
CTRL.SPEED Don't care; speed setting is established from PHY's internal indication to the MAC
(SPD_IND) after PHY has auto-negotiated a successful link-up.
STATUS.FD Reflects the actual duplex setting (FDX) negotiated by the PHY and indicated to
MAC.
STATUS.LU Reflects link indication (LINK) from PHY qualified with CTRL.SLU (set to 1b).
STATUS.SPEED Reflects actual speed setting negotiated by the PHY and indicated to the MAC
(SPD_IND).
4.5.7.2.2 MAC Duplex and Speed Settings Forced by Software Based on Resolution of PHY
(CTRL.FRCDPLX = 1b, CTRL.FRCSPD = 1b)
CTRL.FD Set by software based on reading PHY status register after PHY has auto-
negotiated a successful link-up.
CTRL.SLU Must be set to 1b by software to enable communications between MAC and PHY.