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Commit 85100936 authored by Pepping's avatar Pepping
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Added generic for bypassing the prefilter.

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libraries/dsp/wpfb/src/vhdl/wpfb_unit.vhd
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− 166
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......@@ -20,170 +20,171 @@
-- along with this program. If not, see <http://www.gnu.org/licenses/>.
--
--------------------------------------------------------------------------------
-- Purpose: Wideband FFT with Subband Statistics and streaming interfaces.
-- Purpose: Wideband FFT with Subband Statistics and streaming interfaces.
--
-- Description: This unit connects an incoming array of streaming interfaces
-- to the wideband fft. The output of the wideband fft is
-- to the wideband fft. The output of the wideband fft is
-- connected to a set of subband statistics units. The statistics
-- can be read via the memory mapped interface.
-- can be read via the memory mapped interface.
-- A control unit takes care of the correct composition of the
-- output streams(sop,eop,sync,bsn,err).
--
-- Remarks: . The unit can handle only one sync at a time. Therfor the
-- Remarks: . The unit can handle only one sync at a time. Therfor the
-- sync interval should be larger than the total pipeline
-- stages of the wideband fft.
-- stages of the wideband fft.
--
-- . The g_coefs_file_prefix points to the location where the files
-- with the initial content for the coefficients memories are located.
-- These files can be created using the python script: create_mifs.py
-- create_mifs.py is located in $UNB/Firmware/dsp/filter/src/python/
-- It is possible to create the mif files based on every possible
-- create_mifs.py is located in $UNB/Firmware/dsp/filter/src/python/
-- It is possible to create the mif files based on every possible
-- configuration of the filterbank in terms of:
-- * wb_factor
-- * nof points
-- * nof_taps
-- * nof_taps
-- . The wbfb unit can handle a wideband factor > 1 (g_wpfb.wb_factor) or
-- a narrowband factor > 1 (g_wpfb.nof_chan). Both factors can NOT be
-- used at the same time.
-- a narrowband factor > 1 (g_wpfb.nof_chan). Both factors can NOT be
-- used at the same time.
library ieee, common_lib, dp_lib, rTwoSDF_lib, st_lib, filter_lib, fft_lib, diag_lib;
use IEEE.std_logic_1164.all;
use STD.textio.all;
use common_lib.common_pkg.all;
use common_lib.common_mem_pkg.all;
use dp_lib.dp_stream_pkg.ALL;
use dp_lib.dp_stream_pkg.ALL;
use rTwoSDF_lib.rTwoSDFPkg.all;
use st_lib.all;
use st_lib.all;
use filter_lib.all;
use filter_lib.fil_pkg.all;
use fft_lib.all;
use fft_lib.fft_pkg.all;
use fft_lib.fft_pkg.all;
use work.wpfb_pkg.all;
entity wpfb_unit is
generic (
g_wpfb : t_wpfb := c_wpfb;
g_stats_ena : boolean := TRUE; -- Enables the statistics unit
g_use_prefilter : boolean := TRUE;
g_stats_ena : boolean := TRUE; -- Enables the statistics unit
g_use_bg : boolean := FALSE;
g_file_index_arr : t_nat_natural_arr := array_init(0, 128, 1);
g_coefs_file_prefix : string := "../../../../filter/build/data/coefs_wide" -- File prefix for the coefficients files.
g_coefs_file_prefix : string := "../../../../filter/build/data/coefs_wide" -- File prefix for the coefficients files.
);
port (
dp_rst : in std_logic := '0';
dp_clk : in std_logic;
dp_clk : in std_logic;
mm_rst : in std_logic;
mm_clk : in std_logic;
ram_fil_coefs_mosi : in t_mem_mosi;
ram_fil_coefs_mosi : in t_mem_mosi;
ram_fil_coefs_miso : out t_mem_miso := c_mem_miso_rst;
ram_st_sst_mosi : in t_mem_mosi; -- Subband statistics registers
ram_st_sst_miso : out t_mem_miso := c_mem_miso_rst;
reg_bg_ctrl_mosi : in t_mem_mosi;
reg_bg_ctrl_miso : out t_mem_miso;
ram_bg_data_mosi : in t_mem_mosi;
ram_bg_data_miso : out t_mem_miso;
in_sosi_arr : in t_dp_sosi_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
out_sosi_arr : out t_dp_sosi_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0)
ram_st_sst_miso : out t_mem_miso := c_mem_miso_rst;
reg_bg_ctrl_mosi : in t_mem_mosi;
reg_bg_ctrl_miso : out t_mem_miso;
ram_bg_data_mosi : in t_mem_mosi;
ram_bg_data_miso : out t_mem_miso;
in_sosi_arr : in t_dp_sosi_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
out_sosi_arr : out t_dp_sosi_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0)
);
end entity wpfb_unit;
architecture str of wpfb_unit is
constant c_nof_stats : natural := g_wpfb.nof_points/g_wpfb.wb_factor;
constant c_fil_ppf : t_fil_ppf := (g_wpfb.wb_factor,
constant c_nof_stats : natural := 2**g_wpfb.nof_chan * g_wpfb.nof_points/g_wpfb.wb_factor;
constant c_fil_ppf : t_fil_ppf := (g_wpfb.wb_factor,
g_wpfb.nof_chan,
g_wpfb.nof_points,
g_wpfb.nof_points,
g_wpfb.nof_taps,
c_nof_complex*g_wpfb.nof_wb_streams, -- Complex FFT always requires 2 filter streams: real and imaginary
g_wpfb.fil_in_dat_w,
g_wpfb.fil_out_dat_w,
g_wpfb.coef_dat_w);
g_wpfb.fil_in_dat_w,
g_wpfb.fil_out_dat_w,
g_wpfb.coef_dat_w);
constant c_fft : t_fft := (g_wpfb.use_reorder,
g_wpfb.use_separate,
g_wpfb.nof_chan,
g_wpfb.wb_factor,
0,
g_wpfb.nof_points,
g_wpfb.fft_in_dat_w,
g_wpfb.fft_out_dat_w,
g_wpfb.stage_dat_w,
g_wpfb.nof_points,
g_wpfb.fft_in_dat_w,
g_wpfb.fft_out_dat_w,
g_wpfb.stage_dat_w,
g_wpfb.guard_w,
g_wpfb.guard_enable,
g_wpfb.stat_data_w,
g_wpfb.stat_data_sz);
g_wpfb.guard_enable,
g_wpfb.stat_data_w,
g_wpfb.stat_data_sz);
constant c_bg_buf_adr_w : natural := ceil_log2(g_wpfb.nof_points/g_wpfb.wb_factor);
constant c_bg_data_file_index_arr : t_nat_natural_arr := array_init(0, 4, 1);
constant c_bg_data_file_prefix : string := "UNUSED";
-- Constants for the configuration of the requantizers between the filter and the fft.
constant c_prod_w : positive := g_wpfb.fil_in_dat_w + g_wpfb.coef_dat_w;
constant c_add_bit_growth : natural := ceil_log2(g_wpfb.nof_taps);
constant c_sum_w : positive := c_prod_w + c_add_bit_growth;
constant c_bg_data_file_prefix : string := "UNUSED";
-- Constants for the configuration of the requantizers between the filter and the fft.
constant c_prod_w : positive := g_wpfb.fil_in_dat_w + g_wpfb.coef_dat_w;
constant c_add_bit_growth : natural := ceil_log2(g_wpfb.nof_taps);
constant c_sum_w : positive := c_prod_w + c_add_bit_growth;
constant c_requant_lsb_w : natural := c_sum_w - g_wpfb.fil_out_dat_w - c_add_bit_growth;
signal ram_st_sst_mosi_arr : t_mem_mosi_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal ram_st_sst_miso_arr : t_mem_miso_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0) := (others => c_mem_miso_rst);
signal ram_st_sst_mosi_arr : t_mem_mosi_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal ram_st_sst_miso_arr : t_mem_miso_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0) := (others => c_mem_miso_rst);
signal fil_in_arr : t_fil_slv_arr(c_nof_complex*g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal fil_out_arr : t_fil_slv_arr(c_nof_complex*g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal fil_out_val : std_logic;
signal fil_out_val : std_logic;
signal fft_in_re_arr : t_fft_slv_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal fft_in_im_arr : t_fft_slv_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal fft_in_val : std_logic;
signal fft_in_val : std_logic;
signal fft_out_re_arr_i : t_fft_slv_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal fft_out_im_arr_i : t_fft_slv_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal fft_out_im_arr_i : t_fft_slv_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal fft_out_re_arr : t_fft_slv_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal fft_out_im_arr : t_fft_slv_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal fft_out_val : std_logic_vector(g_wpfb.nof_wb_streams-1 downto 0);
signal fft_out_sosi_arr : t_dp_sosi_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0) := (others => c_dp_sosi_rst);
signal bg_siso_arr : t_dp_siso_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0) := (others => c_dp_siso_rdy);
signal fft_out_im_arr : t_fft_slv_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
signal fft_out_val : std_logic_vector(g_wpfb.nof_wb_streams-1 downto 0);
signal fft_out_sosi_arr : t_dp_sosi_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0) := (others => c_dp_sosi_rst);
signal bg_siso_arr : t_dp_siso_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0) := (others => c_dp_siso_rdy);
type reg_type is record
in_sosi_arr : t_dp_sosi_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
in_sosi_arr : t_dp_sosi_arr(g_wpfb.nof_wb_streams*g_wpfb.wb_factor-1 downto 0);
end record;
signal r, rin : reg_type;
begin
begin
---------------------------------------------------------------
-- CHECK IF PROVIDED GENERICS ARE ALLOWED.
-- CHECK IF PROVIDED GENERICS ARE ALLOWED.
---------------------------------------------------------------
assert not(g_wpfb.nof_chan /= 0 and g_wpfb.wb_factor /= 1 and rising_edge(dp_clk)) report "nof_chan must be 0 when wb_factor > 1" severity FAILURE;
---------------------------------------------------------------
-- INPUT REGISTER FOR THE SOSI ARRAY
---------------------------------------------------------------
-- The complete input sosi arry is registered.
-- The complete input sosi arry is registered.
comb : process(r, in_sosi_arr)
variable v : reg_type;
begin
v := r;
v.in_sosi_arr := in_sosi_arr;
rin <= v;
v.in_sosi_arr := in_sosi_arr;
rin <= v;
end process comb;
regs : process(dp_clk)
begin
if rising_edge(dp_clk) then
r <= rin;
end if;
end process;
begin
if rising_edge(dp_clk) then
r <= rin;
end if;
end process;
---------------------------------------------------------------
-- COMBINE MEMORY MAPPED INTERFACES
---------------------------------------------------------------
-- Combine the internal array of mm interfaces for the subband
-- statistics to one array that is connected to the port of the
-- Combine the internal array of mm interfaces for the subband
-- statistics to one array that is connected to the port of the
-- fft_wide_unit.
u_mem_mux_sst : entity common_lib.common_mem_mux
generic map (
generic map (
g_nof_mosi => g_wpfb.nof_wb_streams*g_wpfb.wb_factor,
g_mult_addr_w => ceil_log2(g_wpfb.stat_data_sz*c_nof_stats)
)
......@@ -193,21 +194,21 @@ begin
mosi_arr => ram_st_sst_mosi_arr,
miso_arr => ram_st_sst_miso_arr
);
gen_pfb : if g_use_bg = FALSE generate
---------------------------------------------------------------
-- PREPARE INPUT DATA FOR WIDEBAND POLY PHASE FILTER
---------------------------------------------------------------
-- Extract the data from the in_sosi_arr records and resize it
-- Extract the data from the in_sosi_arr records and resize it
-- to fit the format for the fil_ppf_wide unit. The reordering
-- is done in such a way that the filtercoeficients are reused.
-- Note that both the real part and the imaginary part have
-- their own filterchannel.
-- When wb_factor = 4 and nof_wb_streams = 2 the mapping is as
-- follows (S = wb stream number, W = wideband stream number):
-- Note that both the real part and the imaginary part have
-- their own filterchannel.
-- When wb_factor = 4 and nof_wb_streams = 2 the mapping is as
-- follows (S = wb stream number, W = wideband stream number):
--
-- in_sosi_arr | fil_in_arr | fft_in_re_arr | fft_in_im_arr
-- S W | S W | S W | S W
-- in_sosi_arr | fil_in_arr | fft_in_re_arr | fft_in_im_arr
-- S W | S W | S W | S W
-- 0 0 0 | 0 0 0 RE |0 0 0 0 RE |1 0 0 0 IM
-- 1 0 1 | 1 0 0 IM |4 1 0 1 RE |5 1 0 1 IM
-- 2 0 2 | 2 1 0 RE |8 2 0 2 RE |9 2 0 2 IM
......@@ -216,14 +217,14 @@ begin
-- 5 1 1 | 5 0 1 IM |6 5 1 1 RE |7 5 1 1 IM
-- 6 1 2 | 6 1 1 RE |10 6 1 2 RE |11 6 1 2 IM
-- 7 1 3 | 7 1 1 IM |14 7 1 3 RE |15 7 1 3 IM
-- | 8 0 2 RE | |
-- | 9 0 2 IM | |
-- | 10 1 2 RE | |
-- | 11 1 2 IM | |
-- | 12 0 3 RE | |
-- | 13 0 3 IM | |
-- | 14 1 3 RE | |
-- | 15 1 3 IM | |
-- | 8 0 2 RE | |
-- | 9 0 2 IM | |
-- | 10 1 2 RE | |
-- | 11 1 2 IM | |
-- | 12 0 3 RE | |
-- | 13 0 3 IM | |
-- | 14 1 3 RE | |
-- | 15 1 3 IM | |
--
gen_prep_filter_wb_factor: for I in 0 to g_wpfb.wb_factor-1 generate
gen_prep_filter_streams: for J in 0 to g_wpfb.nof_wb_streams-1 generate
......@@ -233,35 +234,42 @@ begin
end generate;
---------------------------------------------------------------
-- THE POLY PHASE FILTER
-- THE POLY PHASE FILTER
---------------------------------------------------------------
u_filter : entity filter_lib.fil_ppf_wide
generic map (
g_fil_ppf => c_fil_ppf,
g_fil_ppf_pipeline => g_wpfb.fil_pipeline,
g_file_index_arr => g_file_index_arr,
g_coefs_file_prefix => g_coefs_file_prefix
)
port map (
dp_clk => dp_clk,
dp_rst => dp_rst,
mm_clk => mm_clk,
mm_rst => mm_rst,
ram_coefs_mosi => ram_fil_coefs_mosi,
ram_coefs_miso => ram_fil_coefs_miso,
in_dat_arr => fil_in_arr,
in_val => r.in_sosi_arr(0).valid,
out_dat_arr => fil_out_arr,
out_val => fil_out_val
);
gen_prefilter : IF g_use_prefilter = TRUE generate
u_filter : entity filter_lib.fil_ppf_wide
generic map (
g_fil_ppf => c_fil_ppf,
g_fil_ppf_pipeline => g_wpfb.fil_pipeline,
g_file_index_arr => g_file_index_arr,
g_coefs_file_prefix => g_coefs_file_prefix
)
port map (
dp_clk => dp_clk,
dp_rst => dp_rst,
mm_clk => mm_clk,
mm_rst => mm_rst,
ram_coefs_mosi => ram_fil_coefs_mosi,
ram_coefs_miso => ram_fil_coefs_miso,
in_dat_arr => fil_in_arr,
in_val => r.in_sosi_arr(0).valid,
out_dat_arr => fil_out_arr,
out_val => fil_out_val
);
end generate;
-- Bypass filter
gen_no_prefilter : if g_use_prefilter = FALSE generate
fil_out_arr <= fil_in_arr;
fil_out_val <= r.in_sosi_arr(0).valid;
end generate;
fft_in_val <= fil_out_val;
fft_in_val <= fil_out_val;
---------------------------------------------------------------
-- THE WIDEBAND FFT
---------------------------------------------------------------
gen_wide_band_fft: if g_wpfb.wb_factor > 1 generate
---------------------------------------------------------------
gen_wide_band_fft: if g_wpfb.wb_factor > 1 generate
---------------------------------------------------------------
-- PREPARE INPUT DATA FOR WIDEBAND FFT
---------------------------------------------------------------
......@@ -278,7 +286,7 @@ begin
generic map(
g_fft => c_fft, -- generics for the WFFT
g_pft_pipeline => g_wpfb.pft_pipeline,
g_fft_pipeline => g_wpfb.fft_pipeline
g_fft_pipeline => g_wpfb.fft_pipeline
)
port map(
clk => dp_clk,
......@@ -289,14 +297,14 @@ begin
out_re_arr => fft_out_re_arr((I+1)*g_wpfb.wb_factor-1 downto I*g_wpfb.wb_factor),
out_im_arr => fft_out_im_arr((I+1)*g_wpfb.wb_factor-1 downto I*g_wpfb.wb_factor),
out_val => fft_out_val(I)
);
end generate;
end generate;
);
end generate;
end generate;
---------------------------------------------------------------
---------------------------------------------------------------
-- THE PIPELINED FFT
---------------------------------------------------------------
gen_pipeline_fft: if g_wpfb.wb_factor = 1 generate
---------------------------------------------------------------
gen_pipeline_fft: if g_wpfb.wb_factor = 1 generate
---------------------------------------------------------------
-- PREPARE INPUT DATA FOR WIDEBAND FFT
---------------------------------------------------------------
......@@ -304,12 +312,12 @@ begin
fft_in_re_arr(I) <= fil_out_arr(I*c_nof_complex);
fft_in_im_arr(I) <= fil_out_arr(I*c_nof_complex+1);
end generate;
gen_prep_pipe_fft_streams: for I in 0 to g_wpfb.nof_wb_streams-1 generate
u_fft_pipe : entity fft_lib.fft_r2_pipe
generic map(
g_fft => c_fft,
g_pipeline => g_wpfb.fft_pipeline
g_fft => c_fft,
g_pipeline => g_wpfb.fft_pipeline
)
port map(
clk => dp_clk,
......@@ -320,17 +328,17 @@ begin
out_re => fft_out_re_arr_i(I)(c_fft.out_dat_w-1 downto 0),
out_im => fft_out_im_arr_i(I)(c_fft.out_dat_w-1 downto 0),
out_val => fft_out_val(I)
);
fft_out_re_arr(I) <= RESIZE_SVEC(fft_out_re_arr_i(I)(c_fft.out_dat_w-1 downto 0), fft_out_re_arr(I)'length);
fft_out_im_arr(I) <= RESIZE_SVEC(fft_out_im_arr_i(I)(c_fft.out_dat_w-1 downto 0), fft_out_im_arr(I)'length);
end generate;
end generate;
);
fft_out_re_arr(I) <= RESIZE_SVEC(fft_out_re_arr_i(I)(c_fft.out_dat_w-1 downto 0), fft_out_re_arr(I)'length);
fft_out_im_arr(I) <= RESIZE_SVEC(fft_out_im_arr_i(I)(c_fft.out_dat_w-1 downto 0), fft_out_im_arr(I)'length);
end generate;
end generate;
---------------------------------------------------------------
-- FFT CONTROL UNIT
---------------------------------------------------------------
-- The fft control unit composes the output array in the dp-
-- streaming format.
-- streaming format.
u_fft_control : entity fft_lib.fft_wide_unit_control
generic map (
g_fft => c_fft,
......@@ -339,18 +347,18 @@ begin
port map(
rst => dp_rst,
clk => dp_clk,
in_re_arr => fft_out_re_arr,
in_im_arr => fft_out_im_arr,
in_val => fft_out_val(0),
ctrl_sosi => r.in_sosi_arr(0),
in_re_arr => fft_out_re_arr,
in_im_arr => fft_out_im_arr,
in_val => fft_out_val(0),
ctrl_sosi => r.in_sosi_arr(0),
out_sosi_arr => fft_out_sosi_arr
);
end generate;
end generate;
----------------------------------------------------------------------------
-- Source: block generator
----------------------------------------------------------------------------
----------------------------------------------------------------------------
gen_bg : if g_use_bg = TRUE generate
u_bg : entity diag_lib.mms_diag_block_gen
generic map(
......@@ -376,47 +384,47 @@ begin
out_siso_arr => bg_siso_arr,
out_sosi_arr => fft_out_sosi_arr
);
end generate;
end generate;
---------------------------------------------------------------
-- SUBBAND STATISTICS
-- SUBBAND STATISTICS
---------------------------------------------------------------
-- For all "wb_factor"x"nof_wb_streams" output streams of the
-- wideband FFT a subband statistics unit is placed if the
-- g_stats_ena is TRUE.
-- For all "wb_factor"x"nof_wb_streams" output streams of the
-- wideband FFT a subband statistics unit is placed if the
-- g_stats_ena is TRUE.
-- Since the subband statistics module uses embedded DSP blocks
-- for multiplication, the incoming data cannot be wider
-- for multiplication, the incoming data cannot be wider
-- than 18 bit.
gen_stats : if g_stats_ena = TRUE generate
gen_stats : if g_stats_ena = TRUE generate
gen_stats_streams: for I in 0 to g_wpfb.nof_wb_streams-1 generate
gen_stats_wb_factor: for J in 0 to g_wpfb.wb_factor-1 generate
u_subband_stats : entity st_lib.st_sst
generic map(
g_nof_stat => c_nof_stats,
g_nof_stat => c_nof_stats,
g_in_data_w => g_wpfb.fft_out_dat_w,
g_stat_data_w => g_wpfb.stat_data_w,
g_stat_data_w => g_wpfb.stat_data_w,
g_stat_data_sz => g_wpfb.stat_data_sz
)
port map (
mm_rst => mm_rst,
mm_clk => mm_clk,
mm_clk => mm_clk,
dp_rst => dp_rst,
dp_clk => dp_clk,
in_complex => fft_out_sosi_arr(I*g_wpfb.wb_factor+J),
ram_st_sst_mosi => ram_st_sst_mosi_arr(I*g_wpfb.wb_factor+J),
ram_st_sst_mosi => ram_st_sst_mosi_arr(I*g_wpfb.wb_factor+J),
ram_st_sst_miso => ram_st_sst_miso_arr(I*g_wpfb.wb_factor+J)
);
end generate;
end generate;
end generate;
-- Connect to the outside world
);
end generate;
end generate;
end generate;
-- Connect to the outside world
gen_output_streams: for I in 0 to g_wpfb.nof_wb_streams-1 generate
gen_output_wb_factor : for J in 0 to g_wpfb.wb_factor-1 generate
out_sosi_arr(I*g_wpfb.wb_factor+J) <= fft_out_sosi_arr(I*g_wpfb.wb_factor+J);
end generate;
end generate;
end generate;
end generate;
end str;
......
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