A.5.3 Intra-bridge signals

The upstream and downstream sides of each bridge component (ACG, SDB, or SUB) communicate using intra-bridge interfaces. Each intra-bridge interface has an AXI5 interface, a Q-Channel device interface, two wakeup signals, and a gating signal.

The following table lists the AXI5 interface signals that connect the upstream side to the downstream side of the bridge component.

Table A-49 Intra-bridge AXI5 interface signals

Signal Direction Description
AW channel signals:
awvalid_i Upstream to downstream Write address valid signal.
awaddr_i[ADDR_WIDTH−1:0] Upstream to downstream Write address signal.
awburst_i[1:0] Upstream to downstream Write burst type signal.
awid_i[ID_WIDTH−1:0] Upstream to downstream Write request ID signal.
awlen_i[7:0] Upstream to downstream Write burst length signal.
awsize_i[2:0] Upstream to downstream Write burst size signal.
awlock_i Upstream to downstream Write lock type signal.
awprot_i[2:0] Upstream to downstream Write protection type signal.
awready_i Downstream to upstream Write address ready signal.
awcache_i[3:0] Upstream to downstream Indicates how transactions are required to progress through a system.
awqos_i[3:0] Upstream to downstream QoS identifier.
awregion_i[3:0] Upstream to downstream Permits a single physical interface on a slave to be used for multiple logical interfaces.
awuser_i[AWUSER_WIDTH−1:0] Upstream to downstream Write address channel User signal.
AR channel signals:
arvalid_i Upstream to downstream Read address valid signal.
araddr_i[ADDR_WIDTH−1:0] Upstream to downstream Read address signal.
arburst_i[1:0] Upstream to downstream Read burst type signal.
arid_i[ID_WIDTH−1:0] Upstream to downstream Read request ID signal.
arlen_i[7:0] Upstream to downstream Read address burst length signal.
arsize_i[2:0] Upstream to downstream Read burst size signal.
arlock_i Upstream to downstream Read lock type signal.
arprot_i[2:0] Upstream to downstream Read protection type signal.
arready_i Downstream to upstream Read address ready signal.
arcache_i[3:0] Upstream to downstream Indicates how transactions are required to progress through a system.
arqos_i[3:0] Upstream to downstream QoS identifier.
arregion_i[3:0] Upstream to downstream Permits a single physical interface on a slave to be used for multiple logical interfaces.
aruser_i[ARUSER_WIDTH−1:0] Upstream to downstream Read address channel User signal.
W channel signals:
wvalid_i Upstream to downstream Write data valid signal.
wlast_i Upstream to downstream Indicates last transfer in a write burst.
wstrb_i[(DATA_WIDTH/8)−1:0] Upstream to downstream Write byte lane strobes.
wdata_i[DATA_WIDTH−1:0] Upstream to downstream Write data signal.
wpoison_i[(DATA_WIDTH−1)/64:0] Upstream to downstream 64-bit data granule corruption indicator.
wuser_i[WUSER_WIDTH−1:0] Upstream to downstream Write data User signal.
wready_i Downstream to upstream Write data ready signal.
R channel signals:
rvalid_i Downstream to upstream Read data valid signal.
rid_i[ID_WIDTH−1:0] Downstream to upstream Read data ID.
rlast_i Downstream to upstream Indicates last transfer in read data.
rdata_i[DATA_WIDTH−1:0] Downstream to upstream Read data.
rresp_i[1:0] Downstream to upstream Read data response.
rready_i Upstream to downstream Read data ready signal.
ruser_i[RUSER_WIDTH−1:0] Downstream to upstream Read data User signal.
rpoison_i[(DATA_WIDTH−1)/64:0] Downstream to upstream 64-bit data granule corruption indicator.
B channel signals:
bvalid_i Downstream to upstream Write response valid signal.
bid_i[ID_WIDTH−1:0] Downstream to upstream Write response ID signal.
buser_i[BUSER_WIDTH−1:0] Downstream to upstream Write response User signal.
bresp_i[1:0] Downstream to upstream Write response signal.
bready_i Upstream to downstream Write response ready signal.

The following table lists the intra-bridge wakeup signals.

Table A-50 Intra-bridge wakeup signals

Signal Direction Description
awakeup_i Upstream to downstream When this signal is HIGH, it indicates that the bridge is initiating activity on this interface.
clk_wake_i Upstream to downstream Forwards a wakeup request for the clock to be active for the downstream side of the bridge.

The following table lists the intra-bridge gating signals.

Table A-51 Intra-bridge gating signal

Signal Direction Description
eg_on_i Downstream to upstream This signal indicates when the downstream side of the bridge component receives an external gating request:

1 = The source of the intra-bridge quiescence request is an external gating request. The bridge cannot deny this request.

0 = The source of the intra-bridge quiescence request is not an external gating request. The bridge can deny the request.

The following table lists the intra-bridge Q-Channel device signals.

Table A-52 Intra-bridge Q-Channel signals

Signal Direction Description
ib_qreqn_i Downstream to upstream This signal indicates when the downstream side of the bridge component issues a quiescence entry or exit request to the upstream side of the bridge component.
ib_qacceptn_i Upstream to downstream This signal indicates when the bridge component accepts the quiescence request.
ib_qdeny_i Upstream to downstream This signal indicates when the bridge component denies the quiescence request.
ib_qactive_i Upstream to downstream This signal indicates when the bridge component is active and also when it requests to exit from quiescence.
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