SPRUII0F May 2019 – June 2024 TMS320F28384D , TMS320F28384D-Q1 , TMS320F28384S , TMS320F28384S-Q1 , TMS320F28386D , TMS320F28386D-Q1 , TMS320F28386S , TMS320F28386S-Q1 , TMS320F28388D , TMS320F28388S
The Extended Receive VLAN Filtering & Routing feature provides two status bits to indicate the comparison result of the VLAN tags.
By default, the MAC indicates the VLAN Filter Status through one bit in the status – VF in RDES2. When Extended RX VLAN filtering and routing is enabled, two status bits are used to indicate the comparison result of VLAN tags. The Outer VLAN Tag Filter Pass and Inner VLAN Tag Filter Pass bits are defined in the following positions The status indicated through these bits is highly dependent on the programming as explained.
In RDES2:
In ARI status: MAC Filter status:
In MRI Status:
Outer VLAN Tag Filter Status (OTS)
Inner VLAN Tag Filter Status (ITS)
The application must look at the status bits and the programming to determine if the Frame has passed or failed the VLAN Filter.
Table 43-20 and Table 43-21 show the possible Filter combinations and the corresponding filter results. These tables explain the scenarios when Double VLAN Processing and Hash VLAN filter are enabled in the design.
Table 43-20 show the possible values of status bits (OTS and ITS) when at least one Perfect filter is enabled.
VTIM | HFO | HFI | PFO | PFI | OTS | ITS |
---|---|---|---|---|---|---|
0 | 0 | 0 | 0 | 1 | 0 | 1/0 |
0 | 0 | 0 | 1 | 0 | 1/0 | 0 |
0 | 0 | 0 | 1 | 1 | 1/0 | 1/0 |
0 | 1 | 0 | 1 | 1 | 1/0 | 1/0 |
0 | 1 | 0 | 1 | 0 | 1/0 | 0 |
0 | 1 | 0 | 0 | 1 | 1/0 | 1/0 |
0 | 0 | 1 | 1 | 1 | 1/0 | 1/0 |
0 | 0 | 1 | 1 | 0 | 1/0 | 1/0 |
0 | 0 | 1 | 0 | 1 | 0 | 1/0 |
1 | 0 | 0 | 0 | 1 | 0 | 1/0 |
1 | 0 | 0 | 1 | 0 | 1/0 | 0 |
1 | 0 | 0 | 1 | 1 | 1/0 | 1/0 |
1 | 1 | 0 | 1 | 1 | 1/0 | 1/0 |
1 | 1 | 0 | 1 | 0 | 1/0 | 0 |
1 | 1 | 0 | 0 | 1 | 1/0 | 1/0 |
1 | 0 | 1 | 1 | 1 | 1/0 | 1/0 |
1 | 0 | 1 | 1 | 0 | 1/0 | 1/0 |
1 | 0 | 1 | 0 | 1 | 0 | 1/0 |
Table 43-21 shows the possible values of status bits (OTS and ITS) when none of the perfect filters are enabled and only the VLAN Hash Filter is enabled.
VTIM | HFO | HFI | OTS | ITS |
---|---|---|---|---|
0 | 0 | 0 | 0 | 0 |
0 | 1 | 0 | 1/0 | 0 |
0 | 0 | 1 | 1/0 | 1/0 |
1 | 0 | 0 | 1/0 | 0 |
1 | 1 | 0 | 1/0 | 0 |
1 | 0 | 1 | 1/0 | 1/0 |
With no Perfect Filters enabled, any VLAN packet is considered to have bypassed the Perfect Filter. If Hash Filter is enabled for one of the Tags, then the respective status bit depends on the Filter's result. The status bits are set to 0, if the VLAN Hash Filter is also not enabled.
If the value of ITS/OTS is shown as 1/0; then the value indicates that the final result is dependent on the enabled relevant filter's result.
Example 1: The second row of Table 43-20 indicates that at least one Perfect Filter is enabled for Outer VLAN tag comparison and none of the filters are enabled for Inner VLAN tag comparison. Inverse VLAN Filtering is not enabled. The bit OTS is given as 1/0. If the received frame passes at least one of the enabled Outer VLAN Tag filters then the bit is set to 1. If the frame does not pass any of the enabled Outer VLAN Tag filters, then the bit is set to 0.
Example 2: The last row of Table 43-20 indicates that Inverse Filtering is enabled, Hash Filter and at least one perfect filter is enabled for Inner VLAN Tag comparison, then if the received frame's Inner VLAN tag mismatches with both the Hash Filter and all the enabled Perfect filters, then the frame has the ITS bit set to 1 or else the ITS bit is set to 0. OTS is set to 0 as no comparison is performed.