Move port_bit() to rtl837x_common.h as PORT_BIT(), a uint16_t shift,
and MAC_ADDR_LEN from rtl837x_lldp.h next to it, and use MAC_ADDR_LEN
for every address in the LACP code instead of a literal 6. Define
lacp_mux_update() before its first caller and drop the forward
declaration, declare variables at the top of their blocks, put the
operator at the end of a continued line, drop the field value comments
of the LACPDU struct, and leave lacp_port_lag to lacp_init() instead of
initialising it in the test environment.
The comments repeated the documentation, described tests or explained
the code to its author. What stays describes the LACPDU structures. The
timer constants are decimal, in units of the LACP timer.
The LACP test now compiles with the shared harness flags and
sdcc_shim.h against the firmware headers, so the copies under
test/lacp/shim are gone. test_port_tables already covers the trunk hash
seed that test/port_hash checked against its own register copies.
lacp_in() declares its locals at the top, which the stricter host build
needs.
The port and group of lacp_in(), the member mask passed to
lacp_lag_set() and the compiler temporaries both functions spilled took
six bytes of DSEG, and with them six bytes of stack. The locals and the
mask live in xdata now, the partner fields go through the scratch word,
and lacp_lag_set() records the new group of a port before it releases
the old one. One byte is left: the group number passed in.
The receive machine armed current_while from the partner's TIMEOUT bit,
so against a partner on the slow rate a port whose LACPDUs stopped with
the link still up stayed in the trunk for the long timeout, two minutes.
802.3ad 43.4.12 starts the timer from the actor's own LACP_Timeout, and
we always advertise the short one: the partner sends every second and is
let go after the short timeout.
Sandbox T23 plays a slow-rate partner that goes quiet and fails on the
code before this.
Dynamic link aggregation on top of the static LAGG, for RTL8372/8373:
receive, selection and mux state machines (coupled mux, one aggregator
per group), with "lacp show" to look inside. Each of the four trunk
groups runs its own aggregator on the candidate ports assigned with
"lag <n> lacp <ports>"; the engine starts with the first such group and
stops with the last.
LACPDUs reach the CPU through the reserved-multicast trap, so delivery
needs no L2 entry and nothing written per VLAN or per PVID. The trap
acts on the address before the VLAN lookup and before the ingress
filters, so a LACPDU also arrives on a port that admits tagged frames
only and on a port STP holds in blocking, neither of which a forwarded
one reaches. A trapped frame carries no VLAN tag,
so lacp_in() takes the offset of the PDU body from TRAP_RX_BODY(). The
action is set with trap_rma_set(), which leaves the flags sharing that
register alone, and "lacp off" puts the slow-protocols drop default
back. doc/lacp.md and doc/link_aggregation.md record what was measured,
including why the trap looked like a dead end at first.
The web UI gets a Static/LACP mode per group on the LAG page with live
status, and the startup-config validator knows the per-group syntax. A
host-side sandbox for the state machines runs in the test harness
together with the LAG hash check. It drives both forms of an incoming
LACPDU, so the body offset of a trapped one is covered as well.
The L2 table page iterated with the "next unicast" read method, so
static multicast entries such as an IGMP group were invisible. It now
iterates with "next address", skips L3 entries (their layout carries IP
addresses where a MAC is expected), and reports the lowest member of a
multicast entry's port mask, so such an entry shows up as a static
entry on that port.
A port taken out of LACP forgets its partner, so "lacp show" after
"lacp off" no longer reports one. Applying the same candidate set to a
group again, as the LAG page does on every Apply, leaves the trunk
alone instead of tearing it down for a second or two. lacp_in() checks
the frame length and ethertype before reading a LACPDU, so a runt or a
foreign frame on the slow-protocols address cannot leave stale buffer
bytes as a partner. The sandbox covers these three in T20-T22. On the
LAG page, LACP mode with no ports checked sends "lag N lacp off", and
the startup-config validator wants at least one port after "lacp".
d00f