aboutsummaryrefslogtreecommitdiffstats
path: root/common
diff options
context:
space:
mode:
Diffstat (limited to 'common')
-rw-r--r--common/nextpnr.h5
-rw-r--r--common/placer1.cc13
-rw-r--r--common/router1.cc2
-rw-r--r--common/timing.cc96
-rw-r--r--common/timing.h4
5 files changed, 52 insertions, 68 deletions
diff --git a/common/nextpnr.h b/common/nextpnr.h
index c4c05ae0..38a313fd 100644
--- a/common/nextpnr.h
+++ b/common/nextpnr.h
@@ -204,6 +204,11 @@ struct DecalXY
{
DecalId decal;
float x = 0, y = 0;
+
+ bool operator==(const DecalXY &other) const
+ {
+ return (decal == other.decal && x == other.x && y == other.y);
+ }
};
struct BelPin
diff --git a/common/placer1.cc b/common/placer1.cc
index 264f1eba..d0771e5c 100644
--- a/common/placer1.cc
+++ b/common/placer1.cc
@@ -75,10 +75,10 @@ class SAPlacer
bool place()
{
log_break();
+ ctx->lock();
size_t placed_cells = 0;
// Initial constraints placer
- ctx->lock();
for (auto &cell_entry : ctx->cells) {
CellInfo *cell = cell_entry.second.get();
auto loc = cell->attrs.find(ctx->id("BEL"));
@@ -112,6 +112,7 @@ class SAPlacer
}
int constr_placed_cells = placed_cells;
log_info("Placed %d cells based on constraints.\n", int(placed_cells));
+ ctx->yield();
// Sort to-place cells for deterministic initial placement
std::vector<CellInfo *> autoplaced;
@@ -123,28 +124,25 @@ class SAPlacer
}
std::sort(autoplaced.begin(), autoplaced.end(), [](CellInfo *a, CellInfo *b) { return a->name < b->name; });
ctx->shuffle(autoplaced);
- ctx->unlock();
// Place cells randomly initially
log_info("Creating initial placement for remaining %d cells.\n", int(autoplaced.size()));
for (auto cell : autoplaced) {
- ctx->lock();
place_initial(cell);
placed_cells++;
if ((placed_cells - constr_placed_cells) % 500 == 0)
log_info(" initial placement placed %d/%d cells\n", int(placed_cells - constr_placed_cells),
int(autoplaced.size()));
- ctx->unlock();
}
if ((placed_cells - constr_placed_cells) % 500 != 0)
log_info(" initial placement placed %d/%d cells\n", int(placed_cells - constr_placed_cells),
int(autoplaced.size()));
+ ctx->yield();
log_info("Running simulated annealing placer.\n");
// Calculate metric after initial placement
- ctx->lock();
curr_metric = 0;
curr_tns = 0;
for (auto &net : ctx->nets) {
@@ -152,7 +150,6 @@ class SAPlacer
metrics[net.first] = wl;
curr_metric += wl;
}
- ctx->unlock();
int n_no_progress = 0;
wirelen_t min_metric = curr_metric;
@@ -257,7 +254,7 @@ class SAPlacer
ctx->yield();
}
// Final post-pacement validitiy check
- ctx->lock();
+ ctx->yield();
for (auto bel : ctx->getBels()) {
IdString cell = ctx->getBoundBelCell(bel);
if (!ctx->isBelLocationValid(bel)) {
@@ -275,7 +272,7 @@ class SAPlacer
}
}
}
- compute_fmax(ctx, true /* print_fmax */);
+ timing_analysis(ctx, true /* print_fmax */);
ctx->unlock();
return true;
}
diff --git a/common/router1.cc b/common/router1.cc
index 2ae54245..d1551363 100644
--- a/common/router1.cc
+++ b/common/router1.cc
@@ -814,7 +814,7 @@ bool router1(Context *ctx)
#ifndef NDEBUG
ctx->check();
#endif
- compute_fmax(ctx, true /* print_fmax */, true /* print_path */);
+ timing_analysis(ctx, true /* print_fmax */, true /* print_path */);
ctx->unlock();
return true;
} catch (log_execution_error_exception) {
diff --git a/common/timing.cc b/common/timing.cc
index f720b772..20cfd1b5 100644
--- a/common/timing.cc
+++ b/common/timing.cc
@@ -26,14 +26,13 @@
NEXTPNR_NAMESPACE_BEGIN
-typedef std::unordered_map<const PortInfo *, delay_t> UpdateMap;
typedef std::list<const PortRef *> PortRefList;
-static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t slack, UpdateMap *updates,
+static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t slack, bool update,
delay_t &min_slack, PortRefList *current_path, PortRefList *crit_path);
// Follow a path, returning budget to annotate
-static delay_t follow_user_port(Context *ctx, PortRef &user, int path_length, delay_t slack, UpdateMap *updates,
+static delay_t follow_user_port(Context *ctx, PortRef &user, int path_length, delay_t slack, bool update,
delay_t &min_slack, PortRefList *current_path, PortRefList *crit_path)
{
delay_t value;
@@ -58,7 +57,7 @@ static delay_t follow_user_port(Context *ctx, PortRef &user, int path_length, de
if (is_path) {
NetInfo *net = port.second.net;
if (net) {
- delay_t path_budget = follow_net(ctx, net, path_length, slack - comb_delay, updates, min_slack,
+ delay_t path_budget = follow_net(ctx, net, path_length, slack - comb_delay, update, min_slack,
current_path, crit_path);
value = std::min(value, path_budget);
}
@@ -66,16 +65,10 @@ static delay_t follow_user_port(Context *ctx, PortRef &user, int path_length, de
}
}
}
-
- if (updates) {
- auto ret = updates->emplace(&user.cell->ports.at(user.port), value);
- if (!ret.second)
- ret.first->second = std::min(value, ret.first->second);
- }
return value;
}
-static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t slack, UpdateMap *updates,
+static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t slack, bool update,
delay_t &min_slack, PortRefList *current_path, PortRefList *crit_path)
{
delay_t net_budget = slack / (path_length + 1);
@@ -92,14 +85,16 @@ static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t s
}
net_budget = std::min(net_budget,
follow_user_port(ctx, usr, pl, slack - ctx->getNetinfoRouteDelay(net, i),
- updates, min_slack, current_path, crit_path));
+ update, min_slack, current_path, crit_path));
+ if (update)
+ usr.budget = std::min(usr.budget, net_budget);
if (crit_path)
current_path->pop_back();
}
return net_budget;
}
-static delay_t compute_min_slack(Context *ctx, UpdateMap *updates, PortRefList *crit_path)
+static delay_t walk_paths(Context *ctx, bool update, PortRefList *crit_path)
{
delay_t default_slack = delay_t(1.0e12 / ctx->target_freq);
delay_t min_slack = default_slack;
@@ -119,7 +114,7 @@ static delay_t compute_min_slack(Context *ctx, UpdateMap *updates, PortRefList *
if (ctx->getCellDelay(cell.second.get(), clock_domain, port.first, clkToQ))
slack -= clkToQ;
if (port.second.net)
- follow_net(ctx, port.second.net, 0, slack, updates, min_slack, &current_path, crit_path);
+ follow_net(ctx, port.second.net, 0, slack, update, min_slack, &current_path, crit_path);
}
}
}
@@ -140,32 +135,10 @@ void assign_budget(Context *ctx)
}
}
- UpdateMap updates;
- delay_t min_slack = compute_min_slack(ctx, &updates, nullptr);
+ delay_t min_slack = walk_paths(ctx, true, nullptr);
- // 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);
- }
-
- // Update the budgets
for (auto &net : ctx->nets) {
- for (size_t i = 0; i < net.second->users.size(); ++i) {
- auto &user = net.second->users[i];
- auto pi = &user.cell->ports.at(user.port);
- auto budget = ctx->getNetinfoRouteDelay(net.second.get(), i);
- auto it = updates.find(pi);
- if (it != updates.end())
- budget += it->second;
- user.budget = ctx->getBudgetOverride(net.second.get(), i, budget);
-
+ 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 "
@@ -180,27 +153,29 @@ void assign_budget(Context *ctx)
}
}
+ // 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)
{
- UpdateMap updates;
- delay_t min_slack = compute_min_slack(ctx, &updates, nullptr);
-
- // Update the budgets
- for (auto &net : ctx->nets) {
- for (size_t i = 0; i < net.second->users.size(); ++i) {
- auto &user = net.second->users[i];
- auto pi = &user.cell->ports.at(user.port);
- auto budget = ctx->getNetinfoRouteDelay(net.second.get(), i);
- auto it = updates.find(pi);
- if (it != updates.end())
- budget += it->second;
- user.budget = ctx->getBudgetOverride(net.second.get(), i, budget);
+ delay_t min_slack = walk_paths(ctx, true, nullptr);
- // Post-update check
- if (ctx->verbose) {
+ if (ctx->verbose) {
+ 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",
@@ -215,21 +190,25 @@ void update_budget(Context *ctx)
}
}
- // If user has not specified a frequency, adjust the frequency dynamically:
+ // 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);
- ctx->target_freq = 1e12 / (default_slack - min_slack);
+ 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 update = %d, target Fmax for next update = %.2f MHz\n", min_slack,
+ log_info("minimum slack for this assign = %d, target Fmax for next update = %.2f MHz\n", min_slack,
ctx->target_freq / 1e6);
}
}
-void compute_fmax(Context *ctx, bool print_fmax, bool print_path)
+delay_t timing_analysis(Context *ctx, bool print_fmax, bool print_path)
{
delay_t default_slack = delay_t(1.0e12 / ctx->target_freq);
PortRefList crit_path;
- delay_t min_slack = compute_min_slack(ctx, nullptr, &crit_path);
+ delay_t min_slack = walk_paths(ctx, false, &crit_path);
if (print_path) {
delay_t total = 0;
log_break();
@@ -267,6 +246,7 @@ void compute_fmax(Context *ctx, bool print_fmax, bool print_path)
}
if (print_fmax)
log_info("estimated Fmax = %.2f MHz\n", 1e6 / (default_slack - min_slack));
+ return min_slack;
}
NEXTPNR_NAMESPACE_END
diff --git a/common/timing.h b/common/timing.h
index a1e12ab3..de4f7bbe 100644
--- a/common/timing.h
+++ b/common/timing.h
@@ -30,7 +30,9 @@ void assign_budget(Context *ctx);
// Evenly redistribute the total path slack amongst all sinks on each path
void update_budget(Context *ctx);
-void compute_fmax(Context *ctx, bool print_fmax = false, bool print_path = false);
+// Perform timing analysis and return the minimum path slack,
+// optionally, print out the fmax and critical path
+delay_t timing_analysis(Context *ctx, bool print_fmax = false, bool print_path = false);
NEXTPNR_NAMESPACE_END
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-27 20:58:24 +0000