tlul_socket_1n

Steer one TL-UL host onto N device ports.

Route each A-channel request to tl_d_o[dev_select_i] through optional host and per-device FIFOs; dev_select_i travels through the host FIFO with its request. Ports that are not selected see a_valid low, blanked a_data and deliberately bad integrity. Maximum N is 63.

Stall switching to another device until all outstanding responses from other devices have returned: keep a counter of outstanding requests and wait until it is zero before switching.

Return an error response from an internal tlul_err_resp when dev_select_i is outside 0..N-1. The instantiator may force an error with any illegal select; all ones is recommended for visibility. When EXPLICIT_ERRS is set, size dev_select_i as $clog2(N+1) bits so value N is always representable and can request that error.

FIFO parameters:

H_REQ_PASS/H_RSP_PASS and D_REQ_PASS/D_RSP_PASS allow fall-through when the corresponding FIFO is empty.
H_REQ_DEPTH/H_RSP_DEPTH and D_REQ_DEPTH/D_RSP_DEPTH set FIFO depths; the D* depths pack one nibble per device.

Parameters

Table 1. Parameters
Name	Type	Default	Description
`N`	`int unsigned`	`4`	Number of device ports (max 63).
`H_REQ_PASS`	`bit`	`1'b1`	Host request FIFO fall-through.
`H_RSP_PASS`	`bit`	`1'b1`	Host response FIFO fall-through.
`D_REQ_PASS`	`bit [N-1:0]`	`{N{1'b1}}`	Per-device request FIFO fall-through.
`D_RSP_PASS`	`bit [N-1:0]`	`{N{1'b1}}`	Per-device response FIFO fall-through.
`H_REQ_DEPTH`	`bit [3:0]`	`4'h1`	Host request FIFO depth.
`H_RSP_DEPTH`	`bit [3:0]`	`4'h1`	Host response FIFO depth.
`D_REQ_DEPTH`	`bit [N*4-1:0]`	`{N{4'h1}}`	Packed per-device request FIFO depths.
`D_RSP_DEPTH`	`bit [N*4-1:0]`	`{N{4'h1}}`	Packed per-device response FIFO depths.
`EXPLICIT_ERRS`	`bit`	`1'b1`	Widen select so N can request an error.
`Nwd`	`int unsigned`	`$clog2(EXPLICIT_ERRS ? N+1 : N)`	Width of dev_select_i.

Ports

Table 2. Ports
Name	Direction	Type	Description
`clk_i`	input		System clock.
`rst_ni`	input		Active-low reset.
`tl_h_i`	input	`tlul_pkg::tl_h2d_t`	Host-side TL-UL request.
`tl_h_o`	output	`tlul_pkg::tl_d2h_t`	Host-side TL-UL response.
`tl_d_o`	output	`tlul_pkg::tl_h2d_t`	Per-device TL-UL requests.
`tl_d_i`	input	`tlul_pkg::tl_d2h_t`	Per-device TL-UL responses.
`dev_select_i`	input	`[Nwd-1:0]`	Device index; N and above return an error.