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timing: remove the articial clock delay inflation

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Rowan Goemans 2024-09-19 18:15:53 +02:00 committed by myrtle
parent 0fce4b8f4e
commit 098dcaedec
2 changed files with 4 additions and 19 deletions
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20
common/kernel/timing.cc
View File

@ -573,10 +573,7 @@ void TimingAnalyser::walk_forward()
init_arrival += fanin.value.delayPair(); init_arrival += fanin.value.delayPair();
// Include the clock delay if clock_skew analysis is enabled // Include the clock delay if clock_skew analysis is enabled
if (with_clock_skew) { if (with_clock_skew) {
auto clock_delay = ports.at(CellPortKey(sp.first.cell, fanin.other_port)).route_delay; init_arrival += ports.at(CellPortKey(sp.first.cell, fanin.other_port)).route_delay;
clock_delay.min_delay = clock_delay_fac * clock_delay.min_delay;
clock_delay.max_delay = clock_delay_fac * clock_delay.max_delay;
init_arrival += clock_delay;
} }
break; break;
} }
@ -633,10 +630,7 @@ void TimingAnalyser::walk_backward()
if (fanin.type == CellArc::SETUP && fanin.other_port == ep.second) { if (fanin.type == CellArc::SETUP && fanin.other_port == ep.second) {
if (with_clock_skew) { if (with_clock_skew) {
auto clock_delay = ports.at(CellPortKey(ep.first.cell, fanin.other_port)).route_delay; init_required += ports.at(CellPortKey(ep.first.cell, fanin.other_port)).route_delay;
clock_delay.min_delay = clock_delay_fac * clock_delay.min_delay;
clock_delay.max_delay = clock_delay_fac * clock_delay.max_delay;
init_required += clock_delay;
} }
init_required.min_delay -= fanin.value.maxDelay(); init_required.min_delay -= fanin.value.maxDelay();
} }
@ -707,8 +701,6 @@ dict<domain_id_t, delay_t> TimingAnalyser::max_delay_by_domain_pairs()
for (auto &fanin : ep_port.cell_arcs) { for (auto &fanin : ep_port.cell_arcs) {
if (fanin.type == CellArc::SETUP) { if (fanin.type == CellArc::SETUP) {
auto clock_delay = ports.at(CellPortKey(ep.first.cell, fanin.other_port)).route_delay; auto clock_delay = ports.at(CellPortKey(ep.first.cell, fanin.other_port)).route_delay;
clock_delay.min_delay = clock_delay_fac * clock_delay.min_delay;
clock_delay.max_delay = clock_delay_fac * clock_delay.max_delay;
delay += clock_delay.minDelay(); delay += clock_delay.minDelay();
} }
} }
@ -722,8 +714,6 @@ dict<domain_id_t, delay_t> TimingAnalyser::max_delay_by_domain_pairs()
for (auto &fanin : sp_port.cell_arcs) { for (auto &fanin : sp_port.cell_arcs) {
if (fanin.type == CellArc::CLK_TO_Q) { if (fanin.type == CellArc::CLK_TO_Q) {
auto clock_delay = ports.at(CellPortKey(sp.cell->name, fanin.other_port)).route_delay; auto clock_delay = ports.at(CellPortKey(sp.cell->name, fanin.other_port)).route_delay;
clock_delay.min_delay = clock_delay_fac * clock_delay.min_delay;
clock_delay.max_delay = clock_delay_fac * clock_delay.max_delay;
delay -= clock_delay.maxDelay(); delay -= clock_delay.maxDelay();
} }
} }
@ -1000,10 +990,8 @@ CriticalPath TimingAnalyser::build_critical_path_report(domain_id_t domain_pair,
if (with_clock_skew && register_start && register_end && (same_clock || related_clock)) { if (with_clock_skew && register_start && register_end && (same_clock || related_clock)) {
auto clock_delay_launch = auto clock_delay_launch = ctx->getNetinfoRouteDelay(sp_clk_net, PortRef{sp_cell, sp_clk_info.clock_port});
clock_delay_fac * ctx->getNetinfoRouteDelay(sp_clk_net, PortRef{sp_cell, sp_clk_info.clock_port}); auto clock_delay_capture = ctx->getNetinfoRouteDelay(ep_clk_net, PortRef{ep_cell, ep_clk_info.clock_port});
auto clock_delay_capture =
clock_delay_fac * ctx->getNetinfoRouteDelay(ep_clk_net, PortRef{ep_cell, ep_clk_info.clock_port});
delay_t clock_skew = clock_delay_launch - clock_delay_capture; delay_t clock_skew = clock_delay_launch - clock_delay_capture;

3
common/kernel/timing.h
View File

@ -101,9 +101,6 @@ struct TimingAnalyser
// Enable analysis of clock skew between FFs. // Enable analysis of clock skew between FFs.
bool with_clock_skew = false; bool with_clock_skew = false;
// REMOVE ME once approved
delay_t clock_delay_fac = 1;
bool setup_only = false; bool setup_only = false;
bool have_loops = false; bool have_loops = false;
bool updated_domains = false; bool updated_domains = false;