From eeeecf5af9e6bddfc35dd218994f4cb9dca8cfcd Mon Sep 17 00:00:00 2001 From: Eric Kooistra <kooistra@astron.nl> Date: Thu, 19 Jan 2023 16:18:07 +0100 Subject: [PATCH] Try c_sdp_W_fft_stage_dat = 25b. --- .../lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/applications/lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd b/applications/lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd index 07d8faf127..f23ce1bf86 100644 --- a/applications/lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd +++ b/applications/lofar2/libraries/sdp/src/vhdl/sdp_pkg.vhd @@ -194,11 +194,18 @@ PACKAGE sdp_pkg is -- fft_out_gain_w + 6b = 26b. -- . The raw_dat_w for FFT output of real input is fft_stage_dat_w + 1, -- because the use_separate in the FFT feature does not divide by 2. - -- This implies that preferrably fft_stage_dat_w <= 26, to fit the 18x27 + -- This implies that preferrably fft_stage_dat_w <= 26, to fit the 27b -- multiplier resources. + -- . Increasing fft_stage_dat_w from 24b to 26b does increase M20K usage: + -- 24b 26b + -- FFT 6 x 27 M20K, 6 x 28 M20K, due to separate + -- BF 2 x 403 M20K, 2 x 397 M20K, due to reorder_col + -- where 6 = c_sdp_P_pfb and 2 = c_sdp_N_beamsets. + -- The total design increase is 18 m20K = 2.5 % and 4000 FF = 1.2 %. The + -- nof DSP remains 611. CONSTANT c_sdp_W_fil_backoff : NATURAL := 1; CONSTANT c_sdp_W_fft_guard : NATURAL := 1; - CONSTANT c_sdp_W_fft_stage_dat : NATURAL := 24; -- TODO try 26b, compare synthesis results + CONSTANT c_sdp_W_fft_stage_dat : NATURAL := 25; -- TODO try 26b, compare synthesis results CONSTANT c_sdp_W_fft_in_dat : NATURAL := c_sdp_W_fft_stage_dat - c_sdp_W_fft_guard; CONSTANT c_sdp_W_fft_out_gain : NATURAL := 2; CONSTANT c_sdp_W_stat_data : NATURAL := c_sdp_W_subband * 2 + ceil_log2(c_sdp_N_int_sub_hi); -- = 54 -- GitLab