Information

Enhanced Three-Speed Ethernet Controllers
MPC8308 PowerQUICC II Pro Processor Reference Manual, Rev. 1
Freescale Semiconductor 16-149
16.6.4.2.3 Special-Case Rules
It is frequently useful to create rules that are guaranteed to succeed or fail, specifically to enforce a default
filing decision or act as null entries. Suggested constructions for such rules are shown in Table 16-139.
16.6.4.2.4 Filer Interrupt Events
The filer can produce three interrupt events in IEVENT. Event FIR indicates an error condition where the
filer was unable to provide a definite result, either because no rule in the table succeeded, or because
frames arrived too rapidly to complete searching of the table. Event FIQ indicates that the filer accepted a
frame to a RxBD ring that was not enabled in RQCTRL (this can also occur if the filer is disabled, but
RxBD ring 0—default queue or FSQEN mode queue—is not enabled). FIQ is also asserted in the case
where no rule in the entire table succeeded. The various combinations of these interrupt events and their
interpretation appear in Table 16-140.
A functional interrupt is provided via use of the general purpose interrupt (GPI) bit in the filer table. When
a property matches the value in the RQPROP entry at this index, and REJ = 0 and AND = 0, the filer will
set IEVENT[FGPI] when the corresponding receive frame is written to memory. This allows the user to
set up a filer rule where the core will be interrupted upon the reception of ‘special’ frames.
If the timer is enabled (TMR_CTRL[TE] = 1), then the interrupt dedicated for timer events (in addition to
the usual receive, transmit and error interrupts) will be asserted.
Table 16-139. Special Filer Rules
Rule Description
RQCTRL Fields
RQPROP Word
RQCTRL
Word
1
1
Hexadecimal digits qq denotes field Q shifted left 2 bits.
CLE REJ AND Q CMP PID
Default file—Always file frame to ring Q 0 0 0 Q 01 0000 0x0000_0000 0x0000_qq20
Default reject—Always discard frame 0 1 0 000_000 01 0000 0x0000_0000 0x0000_0120
Empty rule in AND—Always matches 0/1
2
2
Set CLE = 1 if the empty rule guards a cluster.
0 1 000_000 01 0000 0xFFFF_FFFF 0x0000_00A0
Empty rule in rule set—Always fails 0/1
3
3
Set CLE = 1 if the empty rule occurs at the end of a cluster.
0 0 000_000 11 0000 0xFFFF_FFFF 0x0000_0060
Table 16-140. Receive Queue Filer Interrupt Events
IEVENT[FIR] IEVENT[FIQ] Description
0 0 No error. The filer successfully rejected or filed a frame.
0 1 Illegal queue error. The filer accepted a frame to a RxBD ring that is disabled (including ring 0 if
filing is disabled).
1 0 Partial search error. The filer did not have sufficient time to complete its search of the filer table.
1 1 No matching rule error. The filer searched all 256 entries of the filer table without finding a rule
that succeeds.