RM0321 Datasheet, PDF (191/584 Pages) STMicroelectronics – SPEAr320S address map and registers

RM0321
Fast Ethernet port (MII0)
updated - pass or fail - in the corresponding bits in the received frame status word
(Receive Descriptor 0, RDES0).
Clearing this bit, only frames that pass the SA/DA address filter are passed to the
application.
● HPF
When set, this bit configures the address filter to pass a frame if it matches either the
perfect filtering or the hash filtering as set by HMC or HUC bits. When low and if the
HUC/HMC bit is set, the frame is passed only if it matches the Hash filter.
● SAF
Setting this bit, the MAC drops frame when SA filter fails (that is, when SA field of
received frames doesn't match with the values programmed in the enabled SA
registers). Clearing this bit, the MAC Core forwards the received frame to the
application and with the updated received frame status word (Receive Descriptor 0,
RDES0, section 1.2.3.1) depending on the SA address comparison.
● SAIF
Setting this bit, the frames whose SA matches the SA registers will be marked as failing
the SA address filter (inverse filtering mode). Otherwise (bit cleared), frames whose SA
doesn't match the SA registers will be marked as failing the SA address filter (nominal
filtering mode).
● PCF
This 2 bit field controls the forwarding of all control frames (including unicast and
multicast PAUSE frames), according to encoding below:
Table 194. PCF field bit assignments
Value
Description
2‘b00
2‘b01
2‘b10
2‘b11
MAC filters all control frames from reaching application
MAC forwards all control frames to application even if they fail the address filter.
MAC forwards all control frames that pass the address filter.
● DBF
Setting this bit, the MAC address filtering module filters all incoming broadcast frames.
● PM
Setting this bit, all received frames with a multicast destination address (first bit in the
destination address is 1'b1) are passed. If this bit is cleared, filtering of multicast frames
depends on HMC field (bit [2]) in this register.
● DAIF
Setting this bit, the unicast/multicast frames whose DA matches the DA registers will be
marked as failing the DA address filter (inverse filtering mode). Otherwise (bit cleared),
frames whose DA doesn't match the DA registers will be marked as failing the DA
address filter (nominal filtering mode).
● HMC
Setting this bit, the MAC performs destination address filtering of received multicast
frames according to the hash table (as set in Register2, MAC, and Register3, MAC, in
section 1.4.2.16 and 1.4.2.17, respectively). Clearing this bit, the MAC performs a
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