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authorEddie Hung <eddieh@ece.ubc.ca>2018-07-28 14:10:48 -0700
committerEddie Hung <eddieh@ece.ubc.ca>2018-07-28 14:10:48 -0700
commitde6d0d20d7d8e4d79fe1f96bc44945326c230fc4 (patch)
tree6217bbd667d6186ffa9dc89c5dda2aaeac357009 /common/timing.cc
parent0eaa92bd6a160696c2f221501d610c99d9231bef (diff)
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Merge update_budget into assign_budget; update as we go along
Diffstat (limited to 'common/timing.cc')
-rw-r--r--common/timing.cc57
1 files changed, 14 insertions, 43 deletions
diff --git a/common/timing.cc b/common/timing.cc
index 20cfd1b5..5a9d8c02 100644
--- a/common/timing.cc
+++ b/common/timing.cc
@@ -83,11 +83,12 @@ static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t s
net_budget = budget;
pl = std::max(1, path_length);
}
+ auto delay = ctx->getNetinfoRouteDelay(net, i);
net_budget = std::min(net_budget,
- follow_user_port(ctx, usr, pl, slack - ctx->getNetinfoRouteDelay(net, i),
+ follow_user_port(ctx, usr, pl, slack - delay,
update, min_slack, current_path, crit_path));
if (update)
- usr.budget = std::min(usr.budget, net_budget);
+ usr.budget = std::min(usr.budget, delay + net_budget);
if (crit_path)
current_path->pop_back();
}
@@ -123,10 +124,13 @@ static delay_t walk_paths(Context *ctx, bool update, PortRefList *crit_path)
return min_slack;
}
-void assign_budget(Context *ctx)
+void assign_budget(Context *ctx, bool quiet)
{
- log_break();
- log_info("Annotating ports with timing budgets\n");
+ if (!quiet) {
+ log_break();
+ log_info("Annotating ports with timing budgets\n");
+ }
+
// Clear delays to a very high value first
delay_t default_slack = delay_t(1.0e12 / ctx->target_freq);
for (auto &net : ctx->nets) {
@@ -137,42 +141,7 @@ void assign_budget(Context *ctx)
delay_t min_slack = walk_paths(ctx, true, nullptr);
- for (auto &net : ctx->nets) {
- for (auto &user : net.second->users) {
- // Post-update check
- if (ctx->user_freq && 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));
- if (ctx->verbose)
- log_info("port %s.%s, connected to net '%s', has "
- "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));
- }
- }
-
- // If user has not specified a frequency, adjust the target frequency dynamically
- // TODO(eddieh): Tune these factors
- if (!ctx->user_freq) {
- if (min_slack < 0)
- ctx->target_freq = 1e12 / (default_slack - 0.95 * min_slack);
- else
- ctx->target_freq = 1e12 / (default_slack - 1.2 * min_slack);
- if (ctx->verbose)
- log_info("minimum slack for this assign = %d, target Fmax for next update = %.2f MHz\n", min_slack,
- ctx->target_freq / 1e6);
- }
-
- log_info("Checksum: 0x%08x\n", ctx->checksum());
-}
-
-void update_budget(Context *ctx)
-{
- delay_t min_slack = walk_paths(ctx, true, nullptr);
-
- if (ctx->verbose) {
+ if (!quiet || ctx->verbose) {
for (auto &net : ctx->nets) {
for (auto &user : net.second->users) {
// Post-update check
@@ -181,7 +150,7 @@ void update_budget(Context *ctx)
"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));
- else
+ else if (ctx->verbose)
log_info("port %s.%s, connected to net '%s', has "
"timing budget of %fns\n",
user.cell->name.c_str(ctx), user.port.c_str(ctx), net.first.c_str(ctx),
@@ -193,7 +162,6 @@ void update_budget(Context *ctx)
// If user has not specified a frequency, adjust the target frequency dynamically
// TODO(eddieh): Tune these factors
if (!ctx->user_freq) {
- delay_t default_slack = delay_t(1.0e12 / ctx->target_freq);
if (min_slack < 0)
ctx->target_freq = 1e12 / (default_slack - 0.95 * min_slack);
else
@@ -202,6 +170,9 @@ void update_budget(Context *ctx)
log_info("minimum slack for this assign = %d, target Fmax for next update = %.2f MHz\n", min_slack,
ctx->target_freq / 1e6);
}
+
+ if (!quiet)
+ log_info("Checksum: 0x%08x\n", ctx->checksum());
}
delay_t timing_analysis(Context *ctx, bool print_fmax, bool print_path)