test: RX buffer pointer kept at zero on read from empty RX buffer.

test/feature/rx_buf_empty_read_feature_tb.vhd

+--------------------------------------------------------------------------------
+-- 
+-- CTU CAN FD IP Core
+-- Copyright (C) 2015-2018
+-- 
+-- Authors:
+--     Ondrej Ille <ondrej.ille@gmail.com>
+--     Martin Jerabek <martin.jerabek01@gmail.com>
+-- 
+-- Project advisors: 
+-- 	Jiri Novak <jnovak@fel.cvut.cz>
+-- 	Pavel Pisa <pisa@cmp.felk.cvut.cz>
+-- 
+-- Department of Measurement         (http://meas.fel.cvut.cz/)
+-- Faculty of Electrical Engineering (http://www.fel.cvut.cz)
+-- Czech Technical University        (http://www.cvut.cz/)
+-- 
+-- Permission is hereby granted, free of charge, to any person obtaining a copy
+-- of this VHDL component and associated documentation files (the "Component"),
+-- to deal in the Component without restriction, including without limitation
+-- the rights to use, copy, modify, merge, publish, distribute, sublicense,
+-- and/or sell copies of the Component, and to permit persons to whom the
+-- Component is furnished to do so, subject to the following conditions:
+-- 
+-- The above copyright notice and this permission notice shall be included in
+-- all copies or substantial portions of the Component.
+-- 
+-- THE COMPONENT IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+-- AUTHORS OR COPYRIGHTHOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+-- FROM, OUT OF OR IN CONNECTION WITH THE COMPONENT OR THE USE OR OTHER DEALINGS
+-- IN THE COMPONENT.
+-- 
+-- The CAN protocol is developed by Robert Bosch GmbH and protected by patents.
+-- Anybody who wants to implement this IP core on silicon has to obtain a CAN
+-- protocol license from Bosch.
+-- 
+--------------------------------------------------------------------------------
+
+--------------------------------------------------------------------------------
+-- Purpose:
+--  RX Buffer empty - read feature test
+--
+-- Verifies:
+--  1. Verifies that when reading from empty RX Buffer, RX pointer is not
+--     incremented!
+--
+-- Test sequence:
+--  1. Read pointers from RX Buffer, check pointers are 0 (DUT is post reset).
+--  2. Try to read CAN frame from RX Buffer. This should generate at least 4
+--     reads from RX DATA register.
+--  3. Read pointers from RX Buffer, check pointers are still 0.
+--
+--------------------------------------------------------------------------------
+-- Revision History:
+--    18.10.2019   Created file
+--------------------------------------------------------------------------------
+
+context work.ctu_can_synth_context;
+context work.ctu_can_test_context;
+
+use lib.pkg_feature_exec_dispath.all;
+
+package rx_buf_empty_read_feature is
+    procedure rx_buf_empty_read_feature_exec(
+        variable    o               : out    feature_outputs_t;
+        signal      so              : out    feature_signal_outputs_t;
+        signal      rand_ctr        : inout  natural range 0 to RAND_POOL_SIZE;
+        signal      iout            : in     instance_outputs_arr_t;
+        signal      mem_bus         : inout  mem_bus_arr_t;
+        signal      bus_level       : in     std_logic
+    );
+end package;
+
+
+package body rx_buf_empty_read_feature is
+    procedure rx_buf_empty_read_feature_exec(
+        variable    o               : out    feature_outputs_t;
+        signal      so              : out    feature_signal_outputs_t;
+        signal      rand_ctr        : inout  natural range 0 to RAND_POOL_SIZE;
+        signal      iout            : in     instance_outputs_arr_t;
+        signal      mem_bus         : inout  mem_bus_arr_t;
+        signal      bus_level       : in     std_logic
+    ) is
+        variable rand_value         :       real;
+        variable alc                :       natural;
+
+        -- Some unit lost the arbitration...
+        -- 0 - initial , 1-Node 1 turned rec, 2 - Node 2 turned rec
+        variable unit_rec           :     natural := 0;
+
+        variable ID_1               :     natural := 1;
+        variable ID_2               :     natural := 2;
+        variable r_data             :     std_logic_vector(31 downto 0) :=
+                                               (OTHERS => '0');
+        -- Generated frames
+        variable frame_1            :     SW_CAN_frame_type;
+        variable frame_2            :     SW_CAN_frame_type;
+        variable frame_rx           :     SW_CAN_frame_type;
+
+        -- Node status
+        variable stat_1             :     SW_status;
+        variable stat_2             :     SW_status;
+
+        variable pc_dbg             :     SW_PC_Debug;
+        
+        variable txt_buf_state      :     SW_TXT_Buffer_state_type;
+        variable rx_buf_info        :     SW_RX_Buffer_info;
+        variable frames_equal       :     boolean := false;        
+
+        variable id_vect            :     std_logic_vector(28 downto 0);
+    begin
+        o.outcome := true;
+
+        -----------------------------------------------------------------------
+        -- 1. Read pointers from RX Buffer, check pointers are 0 (DUT is post 
+        --    reset).
+        -----------------------------------------------------------------------
+        info("Step 1: Reading RX buffer pointers for first time");
+        get_rx_buf_state(rx_buf_info, ID_1, mem_bus(1));
+        check(rx_buf_info.rx_read_pointer = 0, "Read pointer 0!");
+        check(rx_buf_info.rx_write_pointer = 0, "Write pointer 0!");
+        
+        -----------------------------------------------------------------------
+        -- 2. Try to read CAN frame from RX Buffer. This should generate at 
+        --    least 4 reads from RX DATA register.
+        -----------------------------------------------------------------------
+        info("Step 2: Try to read frame from empty RX Buffer!");
+        CAN_read_frame(frame_rx, ID_1, mem_bus(1));
+
+        ------------------------------------------------------------------------
+        -- 3. Read pointers from RX Buffer, check pointers are still 0.
+        ------------------------------------------------------------------------
+        info("Step 3: Read RX Buffer pointers again!");
+        get_rx_buf_state(rx_buf_info, ID_1, mem_bus(1));
+        check(rx_buf_info.rx_read_pointer = 0, "Read pointer 0!");
+        check(rx_buf_info.rx_write_pointer = 0, "Write pointer 0!");
+
+        wait for 1000 ns;
+
+  end procedure;
+
+end package body;

test/tests_fast.yml

@@ -71,6 +71,7 @@ feature:
         one_shot:
         no_sof_tx:
         rx_status:
+        rx_buf_empty_read:
         tx_counter:
         rx_counter:
         # tran_delay:

test/tests_nightly.yml

@@ -98,6 +98,7 @@ feature:
         one_shot:
         no_sof_tx:
         rx_status:
+        rx_buf_empty_read:
         tx_counter:
         rx_counter:
         # tran_delay: