From e45508f6c41273830312a5b88c5e25f266dc67ae Mon Sep 17 00:00:00 2001 From: David Shah Date: Wed, 20 Jun 2018 15:15:51 +0200 Subject: Improving timing annotator Signed-off-by: David Shah --- common/timing.cc | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'common/timing.cc') diff --git a/common/timing.cc b/common/timing.cc index 5ffd4ea7..a4bda3bb 100644 --- a/common/timing.cc +++ b/common/timing.cc @@ -79,6 +79,14 @@ static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, void assign_budget(Context *ctx, float default_clock) { log_info("Annotating ports with timing budgets\n"); + // Clear delays to a very high value first + delay_t default_slack = delay_t(1.0e12 / default_clock); + for (auto net : ctx->nets) { + for (auto &usr : net.second->users) { + usr.budget = default_slack; + } + } + // Go through all clocked drivers and set up paths for (auto cell : ctx->cells) { for (auto port : cell.second->ports) { if (port.second.type == PORT_OUT) { @@ -93,6 +101,16 @@ void assign_budget(Context *ctx, float default_clock) } } } + // Post-allocation check + for (auto net : ctx->nets) { + for (auto user : net.second->users) { + if (user.budget < 0) + log_warning("port %s.%s, connected to net '%s', has negative " + "timing budget of %fns\n", + user.cell->name.c_str(ctx), user.port.c_str(ctx), + net.first.c_str(ctx), ctx->getDelayNS(user.budget)); + } + } } NEXTPNR_NAMESPACE_END -- cgit v1.2.3