| Line 16... |
Line 16... |
-- # This interface supports classic/standard Wishbone transactions (WB_PIPELINED_MODE = false) #
|
-- # This interface supports classic/standard Wishbone transactions (WB_PIPELINED_MODE = false) #
|
-- # and also pipelined transactions (WB_PIPELINED_MODE = true). #
|
-- # and also pipelined transactions (WB_PIPELINED_MODE = true). #
|
-- # ********************************************************************************************* #
|
-- # ********************************************************************************************* #
|
-- # BSD 3-Clause License #
|
-- # BSD 3-Clause License #
|
-- # #
|
-- # #
|
-- # Copyright (c) 2020, Stephan Nolting. All rights reserved. #
|
-- # Copyright (c) 2021, Stephan Nolting. All rights reserved. #
|
-- # #
|
-- # #
|
-- # Redistribution and use in source and binary forms, with or without modification, are #
|
-- # Redistribution and use in source and binary forms, with or without modification, are #
|
-- # permitted provided that the following conditions are met: #
|
-- # permitted provided that the following conditions are met: #
|
-- # #
|
-- # #
|
-- # 1. Redistributions of source code must retain the above copyright notice, this list of #
|
-- # 1. Redistributions of source code must retain the above copyright notice, this list of #
|
| Line 56... |
Line 56... |
|
|
entity neorv32_wishbone is
|
entity neorv32_wishbone is
|
generic (
|
generic (
|
WB_PIPELINED_MODE : boolean := false; -- false: classic/standard wishbone mode, true: pipelined wishbone mode
|
WB_PIPELINED_MODE : boolean := false; -- false: classic/standard wishbone mode, true: pipelined wishbone mode
|
-- Internal instruction memory --
|
-- Internal instruction memory --
|
MEM_INT_IMEM_USE : boolean := true; -- implement processor-internal instruction memory
|
MEM_INT_IMEM_EN : boolean := true; -- implement processor-internal instruction memory
|
MEM_INT_IMEM_SIZE : natural := 8*1024; -- size of processor-internal instruction memory in bytes
|
MEM_INT_IMEM_SIZE : natural := 8*1024; -- size of processor-internal instruction memory in bytes
|
-- Internal data memory --
|
-- Internal data memory --
|
MEM_INT_DMEM_USE : boolean := true; -- implement processor-internal data memory
|
MEM_INT_DMEM_EN : boolean := true; -- implement processor-internal data memory
|
MEM_INT_DMEM_SIZE : natural := 4*1024; -- size of processor-internal data memory in bytes
|
MEM_INT_DMEM_SIZE : natural := 4*1024; -- size of processor-internal data memory in bytes
|
-- Bus Timeout --
|
-- Bus Timeout --
|
BUS_TIMEOUT : natural := 63 -- cycles after an UNACKNOWLEDGED bus access triggers a bus fault exception
|
BUS_TIMEOUT : natural := 63 -- cycles after an UNACKNOWLEDGED bus access triggers a bus fault exception
|
);
|
);
|
port (
|
port (
|
| Line 146... |
Line 146... |
|
|
|
|
-- Access Control -------------------------------------------------------------------------
|
-- Access Control -------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- access to processor-internal IMEM or DMEM? --
|
-- access to processor-internal IMEM or DMEM? --
|
int_imem_acc <= '1' when (addr_i(31 downto index_size_f(MEM_INT_IMEM_SIZE)) = imem_base_c(31 downto index_size_f(MEM_INT_IMEM_SIZE))) and (MEM_INT_IMEM_USE = true) else '0';
|
int_imem_acc <= '1' when (addr_i(31 downto index_size_f(MEM_INT_IMEM_SIZE)) = imem_base_c(31 downto index_size_f(MEM_INT_IMEM_SIZE))) and (MEM_INT_IMEM_EN = true) else '0';
|
int_dmem_acc <= '1' when (addr_i(31 downto index_size_f(MEM_INT_DMEM_SIZE)) = dmem_base_c(31 downto index_size_f(MEM_INT_DMEM_SIZE))) and (MEM_INT_DMEM_USE = true) else '0';
|
int_dmem_acc <= '1' when (addr_i(31 downto index_size_f(MEM_INT_DMEM_SIZE)) = dmem_base_c(31 downto index_size_f(MEM_INT_DMEM_SIZE))) and (MEM_INT_DMEM_EN = true) else '0';
|
-- access to processor-internal BOOTROM or IO devices? --
|
-- access to processor-internal BOOTROM or IO devices? --
|
int_boot_acc <= '1' when (addr_i(31 downto 16) = boot_rom_base_c(31 downto 16)) else '0'; -- hacky!
|
int_boot_acc <= '1' when (addr_i(31 downto 16) = boot_rom_base_c(31 downto 16)) else '0'; -- hacky!
|
-- actual external bus access? --
|
-- actual external bus access? --
|
xbus_access <= (not int_imem_acc) and (not int_dmem_acc) and (not int_boot_acc);
|
xbus_access <= (not int_imem_acc) and (not int_dmem_acc) and (not int_boot_acc);
|
|
|
