mirror of https://github.com/efabless/caravel.git
335 lines
10 KiB
Verilog
335 lines
10 KiB
Verilog
// SPDX-FileCopyrightText: 2022 Efabless Corporation
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
// SPDX-License-Identifier: Apache-2.0
|
|
|
|
/*
|
|
* gpio_signal_buffering_alt ---
|
|
*
|
|
* This macro buffers long wires between housekeeping and the GPIO control
|
|
* blocks at the top level of caravan. The rule of thumb is to limit any
|
|
* single wire length to approximately 1.3mm. The physical (manhattan)
|
|
* distances and required buffering are as follows:
|
|
*
|
|
* Breakpoints: 1.3, 2.6, 3.9, 5.2, 6.5, 7.8 (mm)
|
|
* # buffers: 1, 2, 3, 4, 5, 6
|
|
*
|
|
* GPIO # wire length (mm) # buffers
|
|
*------------------------------------------------------
|
|
* GPIO 0 0.4 0
|
|
* GPIO 1 0.2 0
|
|
* GPIO 2 0.0 0
|
|
* GPIO 3 0.3 0
|
|
* GPIO 4 0.5 0
|
|
* GPIO 5 0.7 0
|
|
* GPIO 6 1.0 0
|
|
* GPIO 7 1.4 1
|
|
* GPIO 8 1.6 1
|
|
* GPIO 9 1.8 1
|
|
* GPIO 10 2.1 1
|
|
* GPIO 11 2.3 1
|
|
* GPIO 12 2.5 1
|
|
* GPIO 13 2.7 2 RHS
|
|
*-------------------------------------------------------
|
|
* GPIO 25 6.1 4 LHS
|
|
* GPIO 26 5.9 4
|
|
* GPIO 27 5.7 4
|
|
* GPIO 28 5.5 4
|
|
* GPIO 29 5.3 4
|
|
* GPIO 30 5.1 3
|
|
* GPIO 31 4.8 3
|
|
* GPIO 32 4.2 3
|
|
* GPIO 33 4.0 3
|
|
* GPIO 34 3.8 2
|
|
* GPIO 35 3.5 2
|
|
* GPIO 36 3.3 2
|
|
* GPIO 37 3.4 2
|
|
*------------------------------------------------------
|
|
* total number of buffers: 48 (x2 for input and output)
|
|
*
|
|
* OEB lines go to GPIO 0 and 1 (no buffers needed) and GPIO 35-37
|
|
* (2 buffers needed), so OEB lines need 6 additional buffers.
|
|
*
|
|
* The assumption is that all GPIOs on the left-hand side of the chip are
|
|
* routed by taking wires left from the housekeeping across the top of the
|
|
* SoC to the left side, and then up to the destination. Right-hand side
|
|
* connections go directly up the right side from the housekeeping block.
|
|
*
|
|
* Note that signal names are related to the signal being passed through;
|
|
* "in" and "out" refer to the direction of the signal relative to the
|
|
* housekeeping block in the top level. For this macro, unbuffered signals
|
|
* "unbuf" are the inputs, and buffered signals "buf" are the outputs.
|
|
*/
|
|
|
|
module gpio_signal_buffering_alt (
|
|
`ifdef USE_POWER_PINS
|
|
vccd,
|
|
vssd,
|
|
`endif
|
|
mgmt_io_in_unbuf,
|
|
mgmt_io_out_unbuf,
|
|
mgmt_io_oeb_buf,
|
|
mgmt_io_in_buf,
|
|
mgmt_io_out_buf,
|
|
mgmt_io_oeb_unbuf
|
|
);
|
|
|
|
`ifdef USE_POWER_PINS
|
|
input vccd;
|
|
input vssd;
|
|
`endif
|
|
|
|
input [`MPRJ_IO_PADS-1:0] mgmt_io_in_unbuf;
|
|
input [`MPRJ_IO_PADS-1:0] mgmt_io_out_unbuf;
|
|
input [`MPRJ_IO_PADS-1:0] mgmt_io_oeb_unbuf;
|
|
output [`MPRJ_IO_PADS-1:0] mgmt_io_oeb_buf;
|
|
output [`MPRJ_IO_PADS-1:0] mgmt_io_in_buf;
|
|
output [`MPRJ_IO_PADS-1:0] mgmt_io_out_buf;
|
|
|
|
/* Instantiate 48 + 48 + 6 = 101 buffers of size 8 */
|
|
|
|
wire [100:0] buf_in;
|
|
wire [100:0] buf_out;
|
|
|
|
sky130_fd_sc_hd__buf_8 signal_buffers [100:0] (
|
|
`ifdef USE_POWER_PINS
|
|
.VPWR(vccd),
|
|
.VGND(vssd),
|
|
.VPB(vccd),
|
|
.VNB(vssd),
|
|
`endif
|
|
.A(buf_in),
|
|
.X(buf_out)
|
|
);
|
|
|
|
/* First 7 GPIOs have no buffering, so just connect with assignments */
|
|
|
|
assign mgmt_io_in_buf[6:0] = mgmt_io_in_unbuf[6:0];
|
|
assign mgmt_io_out_buf[6:0] = mgmt_io_out_unbuf[6:0];
|
|
|
|
/* Only the last two OEB lines have buffering. All the rest are either */
|
|
/* unbuffered or else unrouted (no-connects at housekeeping) */
|
|
assign mgmt_io_oeb_buf[34:0] = mgmt_io_oeb_unbuf[34:0];
|
|
|
|
/* Now chain them all together */
|
|
|
|
//----------------------------------------
|
|
// mgmt_io_in, right-hand side
|
|
//----------------------------------------
|
|
|
|
assign buf_in[0] = mgmt_io_in_unbuf[7];
|
|
assign mgmt_io_in_buf[7] = buf_out[0];
|
|
|
|
assign buf_in[1] = mgmt_io_in_unbuf[8];
|
|
assign mgmt_io_in_buf[8] = buf_out[1];
|
|
|
|
assign buf_in[2] = mgmt_io_in_unbuf[9];
|
|
assign mgmt_io_in_buf[9] = buf_out[2];
|
|
|
|
assign buf_in[3] = mgmt_io_in_unbuf[10];
|
|
assign mgmt_io_in_buf[10] = buf_out[3];
|
|
|
|
assign buf_in[4] = mgmt_io_in_unbuf[11];
|
|
assign mgmt_io_in_buf[11] = buf_out[4];
|
|
|
|
assign buf_in[5] = mgmt_io_in_unbuf[12];
|
|
assign mgmt_io_in_buf[12] = buf_out[5];
|
|
|
|
assign buf_in[6] = mgmt_io_in_unbuf[13];
|
|
assign buf_in[7] = buf_out[6];
|
|
assign mgmt_io_in_buf[13] = buf_out[7];
|
|
|
|
//----------------------------------------
|
|
// mgmt_io_in, left-hand side
|
|
//----------------------------------------
|
|
|
|
assign buf_in[8] = mgmt_io_in_unbuf[25];
|
|
assign buf_in[9] = buf_out[8];
|
|
assign buf_in[10] = buf_out[9];
|
|
assign buf_in[11] = buf_out[10];
|
|
assign mgmt_io_in_buf[25] = buf_out[11];
|
|
|
|
assign buf_in[12] = mgmt_io_in_unbuf[26];
|
|
assign buf_in[13] = buf_out[12];
|
|
assign buf_in[14] = buf_out[13];
|
|
assign buf_in[15] = buf_out[14];
|
|
assign mgmt_io_in_buf[26] = buf_out[15];
|
|
|
|
assign buf_in[16] = mgmt_io_in_unbuf[27];
|
|
assign buf_in[17] = buf_out[16];
|
|
assign buf_in[18] = buf_out[17];
|
|
assign buf_in[19] = buf_out[18];
|
|
assign mgmt_io_in_buf[27] = buf_out[19];
|
|
|
|
assign buf_in[20] = mgmt_io_in_unbuf[28];
|
|
assign buf_in[21] = buf_out[20];
|
|
assign buf_in[22] = buf_out[21];
|
|
assign buf_in[23] = buf_out[22];
|
|
assign mgmt_io_in_buf[28] = buf_out[23];
|
|
|
|
assign buf_in[24] = mgmt_io_in_unbuf[29];
|
|
assign buf_in[25] = buf_out[24];
|
|
assign buf_in[26] = buf_out[25];
|
|
assign buf_in[27] = buf_out[26];
|
|
assign mgmt_io_in_buf[29] = buf_out[27];
|
|
|
|
assign buf_in[28] = mgmt_io_in_unbuf[30];
|
|
assign buf_in[29] = buf_out[28];
|
|
assign buf_in[30] = buf_out[29];
|
|
assign mgmt_io_in_buf[30] = buf_out[30];
|
|
|
|
assign buf_in[31] = mgmt_io_in_unbuf[31];
|
|
assign buf_in[32] = buf_out[31];
|
|
assign buf_in[33] = buf_out[32];
|
|
assign mgmt_io_in_buf[31] = buf_out[33];
|
|
|
|
assign buf_in[34] = mgmt_io_in_unbuf[32];
|
|
assign buf_in[35] = buf_out[34];
|
|
assign buf_in[36] = buf_out[35];
|
|
assign mgmt_io_in_buf[32] = buf_out[36];
|
|
|
|
assign buf_in[37] = mgmt_io_in_unbuf[33];
|
|
assign buf_in[38] = buf_out[37];
|
|
assign buf_in[39] = buf_out[38];
|
|
assign mgmt_io_in_buf[33] = buf_out[39];
|
|
|
|
assign buf_in[40] = mgmt_io_in_unbuf[34];
|
|
assign buf_in[41] = buf_out[40];
|
|
assign mgmt_io_in_buf[34] = buf_out[41];
|
|
|
|
assign buf_in[42] = mgmt_io_in_unbuf[35];
|
|
assign buf_in[43] = buf_out[42];
|
|
assign mgmt_io_in_buf[35] = buf_out[43];
|
|
|
|
assign buf_in[44] = mgmt_io_in_unbuf[36];
|
|
assign buf_in[45] = buf_out[44];
|
|
assign mgmt_io_in_buf[36] = buf_out[45];
|
|
|
|
assign buf_in[46] = mgmt_io_in_unbuf[37];
|
|
assign buf_in[47] = buf_out[46];
|
|
assign mgmt_io_in_buf[37] = buf_out[47];
|
|
|
|
//----------------------------------------
|
|
// mgmt_io_out, right-hand side
|
|
//----------------------------------------
|
|
|
|
assign buf_in[48] = mgmt_io_out_unbuf[7];
|
|
assign mgmt_io_out_buf[7] = buf_out[48];
|
|
|
|
assign buf_in[49] = mgmt_io_out_unbuf[8];
|
|
assign mgmt_io_out_buf[8] = buf_out[49];
|
|
|
|
assign buf_in[50] = mgmt_io_out_unbuf[9];
|
|
assign mgmt_io_out_buf[9] = buf_out[50];
|
|
|
|
assign buf_in[51] = mgmt_io_out_unbuf[10];
|
|
assign mgmt_io_out_buf[10] = buf_out[51];
|
|
|
|
assign buf_in[52] = mgmt_io_out_unbuf[11];
|
|
assign mgmt_io_out_buf[11] = buf_out[52];
|
|
|
|
assign buf_in[53] = mgmt_io_out_unbuf[12];
|
|
assign mgmt_io_out_buf[12] = buf_out[53];
|
|
|
|
assign buf_in[54] = mgmt_io_out_unbuf[13];
|
|
assign buf_in[55] = buf_out[54];
|
|
assign mgmt_io_out_buf[13] = buf_out[55];
|
|
|
|
//----------------------------------------
|
|
// mgmt_io_out, left-hand side
|
|
//----------------------------------------
|
|
|
|
assign buf_in[56] = mgmt_io_out_unbuf[25];
|
|
assign buf_in[57] = buf_out[56];
|
|
assign buf_in[58] = buf_out[57];
|
|
assign buf_in[59] = buf_out[58];
|
|
assign mgmt_io_out_buf[25] = buf_out[59];
|
|
|
|
assign buf_in[60] = mgmt_io_out_unbuf[26];
|
|
assign buf_in[61] = buf_out[60];
|
|
assign buf_in[62] = buf_out[61];
|
|
assign buf_in[63] = buf_out[62];
|
|
assign mgmt_io_out_buf[26] = buf_out[63];
|
|
|
|
assign buf_in[64] = mgmt_io_out_unbuf[27];
|
|
assign buf_in[65] = buf_out[64];
|
|
assign buf_in[66] = buf_out[65];
|
|
assign buf_in[67] = buf_out[66];
|
|
assign mgmt_io_out_buf[27] = buf_out[67];
|
|
|
|
assign buf_in[68] = mgmt_io_out_unbuf[28];
|
|
assign buf_in[69] = buf_out[68];
|
|
assign buf_in[70] = buf_out[69];
|
|
assign buf_in[71] = buf_out[70];
|
|
assign mgmt_io_out_buf[28] = buf_out[71];
|
|
|
|
assign buf_in[72] = mgmt_io_out_unbuf[29];
|
|
assign buf_in[73] = buf_out[72];
|
|
assign buf_in[74] = buf_out[73];
|
|
assign buf_in[75] = buf_out[74];
|
|
assign mgmt_io_out_buf[29] = buf_out[75];
|
|
|
|
assign buf_in[76] = mgmt_io_out_unbuf[30];
|
|
assign buf_in[77] = buf_out[76];
|
|
assign buf_in[78] = buf_out[77];
|
|
assign mgmt_io_out_buf[30] = buf_out[78];
|
|
|
|
assign buf_in[79] = mgmt_io_out_unbuf[31];
|
|
assign buf_in[80] = buf_out[79];
|
|
assign buf_in[81] = buf_out[80];
|
|
assign mgmt_io_out_buf[31] = buf_out[81];
|
|
|
|
assign buf_in[82] = mgmt_io_out_unbuf[32];
|
|
assign buf_in[83] = buf_out[82];
|
|
assign buf_in[84] = buf_out[83];
|
|
assign mgmt_io_out_buf[32] = buf_out[84];
|
|
|
|
assign buf_in[85] = mgmt_io_out_unbuf[33];
|
|
assign buf_in[86] = buf_out[85];
|
|
assign buf_in[87] = buf_out[86];
|
|
assign mgmt_io_out_buf[33] = buf_out[87];
|
|
|
|
assign buf_in[88] = mgmt_io_out_unbuf[34];
|
|
assign buf_in[89] = buf_out[88];
|
|
assign mgmt_io_out_buf[34] = buf_out[89];
|
|
|
|
assign buf_in[90] = mgmt_io_out_unbuf[35];
|
|
assign buf_in[91] = buf_out[90];
|
|
assign mgmt_io_out_buf[35] = buf_out[91];
|
|
|
|
assign buf_in[92] = mgmt_io_out_unbuf[36];
|
|
assign buf_in[93] = buf_out[92];
|
|
assign mgmt_io_out_buf[36] = buf_out[93];
|
|
|
|
assign buf_in[94] = mgmt_io_out_unbuf[37];
|
|
assign buf_in[95] = buf_out[94];
|
|
assign mgmt_io_out_buf[37] = buf_out[95];
|
|
|
|
//----------------------------------------
|
|
// mgmt_io_oeb, left-hand side (only)
|
|
//----------------------------------------
|
|
|
|
assign buf_in[96] = mgmt_io_oeb_unbuf[35];
|
|
assign buf_in[97] = buf_out[96];
|
|
assign mgmt_io_oeb_buf[35] = buf_out[97];
|
|
|
|
assign buf_in[98] = mgmt_io_oeb_unbuf[36];
|
|
assign buf_in[99] = buf_out[98];
|
|
assign mgmt_io_oeb_buf[36] = buf_out[99];
|
|
|
|
assign buf_in[100] = mgmt_io_oeb_unbuf[37];
|
|
assign buf_in[101] = buf_out[100];
|
|
assign mgmt_io_oeb_buf[37] = buf_out[101];
|
|
|
|
endmodule
|