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Merge pull request #902 from antmicro/nexus-osc-tolerance-2

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Honor nexus OSCA frequency tolerance (corrected)
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gatecat 2022-02-02 08:49:31 +00:00 committed by GitHub
commit 6fceac95c0
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1 changed files with 2 additions and 2 deletions
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nexus/pack.cc
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@ -1988,8 +1988,8 @@ struct NexusPacker
} else if (ci->type == id_OSC_CORE) { } else if (ci->type == id_OSC_CORE) {
int div = int_or_default(ci->params, ctx->id("HF_CLK_DIV"), 128); int div = int_or_default(ci->params, ctx->id("HF_CLK_DIV"), 128);
const float tol = 1.15f; // OSCA has +/-15% frequency tolerance, assume the worst case. const float tol = 1.15f; // OSCA has +/-15% frequency tolerance, assume the worst case.
set_period(ci, id_HFCLKOUT, delay_t(tol * (1.0e6 / 450) * (div + 1))); set_period(ci, id_HFCLKOUT, delay_t((1.0e6 / 450) * (div + 1) / tol));
set_period(ci, id_LFCLKOUT, delay_t(tol * (1.0e3 / 10))); set_period(ci, id_LFCLKOUT, delay_t((1.0e3 / 10) / tol));
} else if (ci->type == id_PLL_CORE) { } else if (ci->type == id_PLL_CORE) {
static const std::array<IdString, 6> div{id_DIVA, id_DIVB, id_DIVC, id_DIVD, id_DIVE, id_DIVF}; static const std::array<IdString, 6> div{id_DIVA, id_DIVB, id_DIVC, id_DIVD, id_DIVE, id_DIVF};
static const std::array<IdString, 6> output{id_CLKOP, id_CLKOS, id_CLKOS2, static const std::array<IdString, 6> output{id_CLKOP, id_CLKOS, id_CLKOS2,