caiyu/nextpnr
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

router2: Hacky workaround for slow Cyclone V convergence

Browse Source 
Signed-off-by: gatecat <gatecat@ds0.me>
This commit is contained in:
gatecat 2021-05-15 13:22:49 +01:00
parent 7fbfd98b8a
commit f318898474
1 changed files with 3 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
common/router2.cc
View File

@ -835,9 +835,6 @@ struct Router2
// Ripup failed arcs to start with // Ripup failed arcs to start with
// Check if arc is already legally routed // Check if arc is already legally routed
if (check_arc_routing(net, i, j)) { if (check_arc_routing(net, i, j)) {
#if 0
ROUTE_LOG_DBG("Arc '%s' (user %zu, arc %zu) already routed skipping.\n", ctx->nameOf(net), i, j);
#endif
continue; continue;
} }
@ -904,10 +901,13 @@ struct Router2
++net_data.fail_count; ++net_data.fail_count;
if ((net_data.fail_count % 3) == 0) { if ((net_data.fail_count % 3) == 0) {
// Every three times a net fails to route, expand the bounding box to increase the search space // Every three times a net fails to route, expand the bounding box to increase the search space
#ifndef ARCH_MISTRAL
// This patch seems to make thing worse for CycloneV, as it slows down the resolution of TD congestion, disable it
net_data.bb.x0 = std::max(net_data.bb.x0 - 1, 0); net_data.bb.x0 = std::max(net_data.bb.x0 - 1, 0);
net_data.bb.y0 = std::max(net_data.bb.y0 - 1, 0); net_data.bb.y0 = std::max(net_data.bb.y0 - 1, 0);
net_data.bb.x1 = std::min(net_data.bb.x1 + 1, ctx->getGridDimX()); net_data.bb.x1 = std::min(net_data.bb.x1 + 1, ctx->getGridDimX());
net_data.bb.y1 = std::min(net_data.bb.y1 + 1, ctx->getGridDimY()); net_data.bb.y1 = std::min(net_data.bb.y1 + 1, ctx->getGridDimY());
#endif
} }
} }
} }