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| author | Clifford Wolf <clifford@clifford.at> | 2019-04-22 09:11:13 +0200 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2019-04-22 09:11:13 +0200 |
| commit | 0e7901e45cc54a9bf76a86dd58092f310f72c90a (patch) | |
| tree | 171df18646f7576f4c804c83d25bf863edbb25e9 | |
| parent | c1dfc7ca963f13d10d4ba211f87bfe09851ae301 (diff) | |
| parent | 71da8363008159fed399ec74318d83e34642d1f2 (diff) | |
| download | yosys-0e7901e45cc54a9bf76a86dd58092f310f72c90a.tar.gz yosys-0e7901e45cc54a9bf76a86dd58092f310f72c90a.tar.bz2 yosys-0e7901e45cc54a9bf76a86dd58092f310f72c90a.zip | |
Merge pull request #941 from Wren6991/sim_lib_io_clke
ice40 cells_sim.v: update clock enable behaviour based on hardware experiments
| -rw-r--r-- | techlibs/ice40/cells_sim.v | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/techlibs/ice40/cells_sim.v b/techlibs/ice40/cells_sim.v index 62a28364b..00843b97c 100644 --- a/techlibs/ice40/cells_sim.v +++ b/techlibs/ice40/cells_sim.v @@ -27,18 +27,27 @@ module SB_IO ( reg dout_q_0, dout_q_1; reg outena_q; + // IO tile generates a constant 1'b1 internally if global_cen is not connected + wire clken_pulled = CLOCK_ENABLE || CLOCK_ENABLE === 1'bz; + reg clken_pulled_ri; + reg clken_pulled_ro; + generate if (!NEG_TRIGGER) begin - always @(posedge INPUT_CLK) if (CLOCK_ENABLE) din_q_0 <= PACKAGE_PIN; - always @(negedge INPUT_CLK) if (CLOCK_ENABLE) din_q_1 <= PACKAGE_PIN; - always @(posedge OUTPUT_CLK) if (CLOCK_ENABLE) dout_q_0 <= D_OUT_0; - always @(negedge OUTPUT_CLK) if (CLOCK_ENABLE) dout_q_1 <= D_OUT_1; - always @(posedge OUTPUT_CLK) if (CLOCK_ENABLE) outena_q <= OUTPUT_ENABLE; + always @(posedge INPUT_CLK) clken_pulled_ri <= clken_pulled; + always @(posedge INPUT_CLK) if (clken_pulled) din_q_0 <= PACKAGE_PIN; + always @(negedge INPUT_CLK) if (clken_pulled_ri) din_q_1 <= PACKAGE_PIN; + always @(posedge OUTPUT_CLK) clken_pulled_ro <= clken_pulled; + always @(posedge OUTPUT_CLK) if (clken_pulled) dout_q_0 <= D_OUT_0; + always @(negedge OUTPUT_CLK) if (clken_pulled_ro) dout_q_1 <= D_OUT_1; + always @(posedge OUTPUT_CLK) if (clken_pulled) outena_q <= OUTPUT_ENABLE; end else begin - always @(negedge INPUT_CLK) if (CLOCK_ENABLE) din_q_0 <= PACKAGE_PIN; - always @(posedge INPUT_CLK) if (CLOCK_ENABLE) din_q_1 <= PACKAGE_PIN; - always @(negedge OUTPUT_CLK) if (CLOCK_ENABLE) dout_q_0 <= D_OUT_0; - always @(posedge OUTPUT_CLK) if (CLOCK_ENABLE) dout_q_1 <= D_OUT_1; - always @(negedge OUTPUT_CLK) if (CLOCK_ENABLE) outena_q <= OUTPUT_ENABLE; + always @(negedge INPUT_CLK) clken_pulled_ri <= clken_pulled; + always @(negedge INPUT_CLK) if (clken_pulled) din_q_0 <= PACKAGE_PIN; + always @(posedge INPUT_CLK) if (clken_pulled_ri) din_q_1 <= PACKAGE_PIN; + always @(negedge OUTPUT_CLK) clken_pulled_ro <= clken_pulled; + always @(negedge OUTPUT_CLK) if (clken_pulled) dout_q_0 <= D_OUT_0; + always @(posedge OUTPUT_CLK) if (clken_pulled_ro) dout_q_1 <= D_OUT_1; + always @(negedge OUTPUT_CLK) if (clken_pulled) outena_q <= OUTPUT_ENABLE; end endgenerate always @* begin |