347 lines
30 KiB
VHDL
347 lines
30 KiB
VHDL
---------------------------------------------------------------------------------------------------------
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--
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-- Name: zpu_soc_pkg.vhd
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-- Created: January 2019
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-- Author(s): Philip Smart
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-- Description: ZPU System On a Chip Configuration
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--
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-- This module contains the System on a Chip configuration for the ZPU.
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--
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-- Credits:
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-- Copyright: (c) 2018 Philip Smart <philip.smart@net2net.org>
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--
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-- History: January 2019 - Initial creation.
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--
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---------------------------------------------------------------------------------------------------------
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-- This source file is free software: you can redistribute it and-or modify
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-- it under the terms of the GNU General Public License as published
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-- by the Free Software Foundation, either version 3 of the License, or
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-- (at your option) any later version.
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--
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-- This source file is distributed in the hope that it will be useful,
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-- but WITHOUT ANY WARRANTY; without even the implied warranty of
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-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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-- GNU General Public License for more details.
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--
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-- You should have received a copy of the GNU General Public License
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-- along with this program. If not, see <http:--www.gnu.org-licenses->.
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---------------------------------------------------------------------------------------------------------
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library ieee;
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library pkgs;
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use ieee.std_logic_1164.all;
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use ieee.numeric_std.all;
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use work.zpu_pkg.all;
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package zpu_soc_pkg is
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-- Choose which CPU to instantiate depending on requirements. Warning, keep the below 5 lines exactly the same
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-- or ensure you update the Makefile as they are set by the Makefile to generate zpu_soc_pkg.vhd
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--
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constant ZPU_SMALL : integer := 0; -- Use the SMALL CPU.
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constant ZPU_MEDIUM : integer := 0; -- Use the MEDIUM CPU.
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constant ZPU_FLEX : integer := 0; -- Use the FLEX CPU.
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constant ZPU_EVO : integer := 1; -- Use the EVOLUTION CPU.
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constant ZPU_EVO_MINIMAL : integer := 0; -- Use the Minimalist EVOLUTION CPU.
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-- Target board declaration.
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--
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constant BOARD_E115 : boolean := false; -- E115 FPGA Board
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constant BOARD_QMV : boolean := true; -- QMTECH Cyclone V FPGA Board
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constant BOARD_DE0 : boolean := false; -- DE0-Nano FPGA Board
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constant BOARD_DE10 : boolean := false; -- DE10-Nano FPGA Board
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constant BOARD_CYC1000 : boolean := false; -- Trenz CYC1000 FPGA Board
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-- Frequencies for the various boards.
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--
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constant SYSCLK_E115_FREQ : integer := 100000000; -- E115 FPGA Board
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constant SYSCLK_QMV_FREQ : integer := 100000000; -- QMTECH Cyclone V FPGA Board
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constant SYSCLK_DE0_FREQ : integer := 100000000; -- DE0-Nano FPGA Board
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constant SYSCLK_DE10_FREQ : integer := 100000000; -- DE10-Nano FPGA Board
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constant SYSCLK_CYC1000_FREQ : integer := 100000000; -- Trenz CYC1000 FPGA Board
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-- ID for the various ZPU models. The format is 2 bytes, MSB=<Model>, LSB=<Revision>
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constant ZPU_ID_SMALL : integer := 16#0101#; -- ID for the ZPU Small in this package.
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constant ZPU_ID_MEDIUM : integer := 16#0201#; -- ID for the ZPU Medium in this package.
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constant ZPU_ID_FLEX : integer := 16#0301#; -- ID for the ZPU Flex in this package.
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constant ZPU_ID_EVO : integer := 16#0401#; -- ID for the ZPU Evo in this package.
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constant ZPU_ID_EVO_MINIMAL : integer := 16#0501#; -- ID for the ZPU Evo Minimal in this package.
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-- EVO CPU specific configuration.
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constant MAX_EVO_L1CACHE_BITS : integer := 5; -- Maximum size in instructions of the Level 0 instruction cache governed by the number of bits, ie. 8 = 256 instruction cache.
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constant MAX_EVO_L2CACHE_BITS : integer := 12; -- Maximum bit size in bytes of the Level 2 instruction cache governed by the number of bits, ie. 8 = 256 byte cache.
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constant MAX_EVO_MXCACHE_BITS : integer := 3; -- Maximum size of the memory transaction cache governed by the number of bits.
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constant MAX_EVO_MIN_L1CACHE_BITS : integer := 4; -- Maximum size in instructions of the Level 0 instruction cache governed by the number of bits, ie. 8 = 256 instruction cache.
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constant MAX_EVO_MIN_L2CACHE_BITS : integer := 12; -- Maximum bit size in bytes of the Level 2 instruction cache governed by the number of bits, ie. 8 = 256 byte cache.
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constant MAX_EVO_MIN_MXCACHE_BITS : integer := 3; -- Maximum size of the memory transaction cache governed by the number of bits.
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-- Settings for various IO devices.
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--
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constant MAX_RX_FIFO_BITS : integer := 8; -- Size of UART RX Fifo.
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constant MAX_TX_FIFO_BITS : integer := 8; -- Size of UART TX Fifo.
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constant MAX_UART_DIVISOR_BITS : integer := 16; -- Maximum number of bits for the UART clock rate generator divisor.
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constant INTR_MAX : integer := 16; -- Maximum number of interrupt inputs.
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constant SYSTEM_FREQUENCY : integer := 100000000; -- Default system clock frequency if not overriden by top level.
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-- SoC specific options.
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--
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constant SOC_IMPL_WB : boolean := EVO_USE_WB_BUS; -- Implement the Wishbone bus and all enabled devices.
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constant SOC_IMPL_WB_I2C : boolean := false; -- Implement I2C over wishbone interface.
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constant SOC_IMPL_TIMER1 : boolean := true; -- Implement Timer 1, an array of prescaled downcounter with enable.
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constant SOC_TIMER1_COUNTERS : integer := 0; -- Number of downcounters in Timer 1. Value is a 2^ array of counters, so 0 = 1 counter.
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constant SOC_IMPL_PS2 : boolean := false; -- Implement PS2 keyboard and mouse hardware.
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constant SOC_IMPL_SPI : boolean := false; -- Implement Serial Peripheral Inteface(s).
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constant SOC_IMPL_SD : boolean := true; -- Implement SD Card interface.
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constant SOC_SD_DEVICES : integer := 1; -- Number of SD card channels implemented.
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constant SOC_IMPL_INTRCTL : boolean := true; -- Implement the prioritised interrupt controller.
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constant SOC_IMPL_IOCTL : boolean := false; -- Implement the IOCTL controller (specific to the MiSTer project).
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constant SOC_IMPL_SOCCFG : boolean := true; -- Implement the SoC Configuration information registers.
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-- Main Boot BRAM on sysbus, contains startup firmware.
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constant SOC_IMPL_BRAM : boolean := true; -- Implement BRAM for the BIOS and initial Stack.
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constant SOC_IMPL_INSN_BRAM : boolean := true; -- Implement dedicated instruction BRAM for the EVO CPU. Any addr access beyond the BRAM size goes to normal memory.
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constant SOC_MAX_ADDR_BRAM_BIT : integer := 16; -- Max address bit of the System BRAM ROM/Stack in bytes, ie. 15 = 32KB or 8K 32bit words. NB. For non evo CPUS you must adjust the maxMemBit parameter in zpu_pkg.vhd to be the same.
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constant SOC_ADDR_BRAM_START : integer := 0; -- Start address of BRAM.
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constant SOC_ADDR_BRAM_END : integer := SOC_ADDR_BRAM_START+(2**SOC_MAX_ADDR_BRAM_BIT); -- End address of BRAM = START + 2^SOC_MAX_ADDR_INSN_BRAM_BIT.
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-- Secondary block of sysbus RAM, typically implemented in BRAM.
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constant SOC_IMPL_RAM : boolean := false; -- Implement RAM using BRAM, typically for Application programs seperate to BIOS.
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constant SOC_MAX_ADDR_RAM_BIT : integer := 13; -- Max address bit of the System RAM.
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constant SOC_ADDR_RAM_START : integer := 32768; -- Start address of RAM.
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constant SOC_ADDR_RAM_END : integer := SOC_ADDR_RAM_START+(2**SOC_MAX_ADDR_RAM_BIT); -- End address of RAM = START + 2^SOC_MAX_ADDR_INSN_BRAM_BIT.
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-- SDRAM on sysbus.
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constant SOC_IMPL_SDRAM : boolean := false; -- Implement Dynamic RAM and controller.
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constant SOC_MAX_ADDR_SDRAM_BIT : integer := 22; -- Max address bit of the System RAM.
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constant SOC_ADDR_SDRAM_START : integer := 65536; -- Start address of RAM.
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constant SOC_ADDR_SDRAM_END : integer := SOC_ADDR_SDRAM_START+(2**SOC_MAX_ADDR_SDRAM_BIT); -- End address of RAM = START + 2^SOC_MAX_ADDR_INSN_BRAM_BIT.
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-- SDRAM on Wishbone bus.
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constant SOC_IMPL_WB_SDRAM : boolean := true; -- Implement SDRAM over wishbone interface.
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constant SOC_MAX_ADDR_WB_SDRAM_BIT: integer := 22; -- Max address bit of the System RAM.
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constant SOC_ADDR_WB_SDRAM_START : integer := 16777216; -- Start address of RAM.
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constant SOC_ADDR_WB_SDRAM_END : integer := SOC_ADDR_WB_SDRAM_START+(2**SOC_MAX_ADDR_WB_SDRAM_BIT); -- End address of RAM = START + 2^SOC_MAX_ADDR_INSN_BRAM_BIT.
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-- Instruction BRAM on sysbus, typically as a 2nd port on the main Boot BRAM (ie. dualport).
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constant SOC_MAX_ADDR_INSN_BRAM_BIT: integer := SOC_MAX_ADDR_BRAM_BIT; -- Max address bit of the dedicated instruction BRAM in bytes, ie. 15 = 32KB or 8K 32bit words.
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constant SOC_ADDR_INSN_BRAM_START : integer := 0; -- Start address of dedicated instrution BRAM.
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constant SOC_ADDR_INSN_BRAM_END : integer := SOC_ADDR_BRAM_START+(2**SOC_MAX_ADDR_INSN_BRAM_BIT); -- End address of dedicated instruction BRAM = START + 2^SOC_MAX_ADDR_INSN_BRAM_BIT.
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constant SOC_RESET_ADDR_CPU : integer := SOC_ADDR_BRAM_START; -- Initial address to start execution from after reset.
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constant SOC_START_ADDR_MEM : integer := SOC_ADDR_BRAM_START; -- Start location of program memory (BRAM/ROM/RAM).
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constant SOC_STACK_ADDR : integer := SOC_ADDR_BRAM_END - 8; -- Stack start address (BRAM/RAM).
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constant SOC_ADDR_IO_START : integer := (2**(maxAddrBit-WB_ACTIVE)) - (2**maxIOBit); -- Start address of the Evo Direct Memory Mapped IO region.
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constant SOC_ADDR_IO_END : integer := (2**(maxAddrBit-WB_ACTIVE)) - 1; -- End address of the Evo Direct Memory Mapped IO region.
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constant SOC_WB_IO_START : integer := 32505856; -- Start address of IO range.
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constant SOC_WB_IO_END : integer := 33554431; -- End address of IO range.
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-- ZPU Evo configuration
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--
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-- Optional Evo CPU hardware features to be implemented.
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constant IMPL_EVO_OPTIMIZE_IM : boolean := true; -- If the instruction cache is enabled, optimise Im instructions to gain speed.
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-- Optional Evo CPU instructions to be implemented in hardware:
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constant IMPL_EVO_ASHIFTLEFT : boolean := true; -- Arithmetic Shift Left (uses same logic so normally combined with ASHIFTRIGHT and LSHIFTRIGHT).
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constant IMPL_EVO_ASHIFTRIGHT : boolean := true; -- Arithmetic Shift Right.
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constant IMPL_EVO_CALL : boolean := true; -- Call to direct address.
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constant IMPL_EVO_CALLPCREL : boolean := true; -- Call to indirect address (add offset to program counter).
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constant IMPL_EVO_DIV : boolean := true; -- 32bit signed division.
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constant IMPL_EVO_EQ : boolean := true; -- Equality test.
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constant IMPL_EVO_EXTENDED_INSN : boolean := true; -- Extended multibyte instruction set.
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constant IMPL_EVO_FIADD32 : boolean := false; -- Fixed point Q17.15 addition.
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constant IMPL_EVO_FIDIV32 : boolean := false; -- Fixed point Q17.15 division.
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constant IMPL_EVO_FIMULT32 : boolean := false; -- Fixed point Q17.15 multiplication.
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constant IMPL_EVO_LOADB : boolean := true; -- Load single byte from memory.
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constant IMPL_EVO_LOADH : boolean := true; -- Load half word (16bit) from memory.
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constant IMPL_EVO_LSHIFTRIGHT : boolean := true; -- Logical shift right.
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constant IMPL_EVO_MOD : boolean := true; -- 32bit modulo (remainder after division).
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constant IMPL_EVO_MULT : boolean := true; -- 32bit signed multiplication.
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constant IMPL_EVO_NEG : boolean := true; -- Negate value in TOS.
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constant IMPL_EVO_NEQ : boolean := true; -- Not equal test.
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constant IMPL_EVO_POPPCREL : boolean := true; -- Pop a value into the Program Counter from a location relative to the Stack Pointer.
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constant IMPL_EVO_PUSHSPADD : boolean := true; -- Add a value to the Stack pointer and push it onto the stack.
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constant IMPL_EVO_STOREB : boolean := true; -- Store/Write a single byte to memory/IO.
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constant IMPL_EVO_STOREH : boolean := true; -- Store/Write a half word (16bit) to memory/IO.
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constant IMPL_EVO_SUB : boolean := true; -- 32bit signed subtract.
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constant IMPL_EVO_XOR : boolean := true; -- Exclusive or of value in TOS.
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-- ZPU Evo Minimal configuration
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--
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-- Optional Evo Minimal CPU hardware features to be implemented.
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constant IMPL_EVOM_OPTIMIZE_IM : boolean := true; -- If the instruction cache is enabled, optimise Im instructions to gain speed.
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-- Optional Evo Minimal CPU instructions to be implemented in hardware:
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constant IMPL_EVOM_ASHIFTLEFT : boolean := false; -- Arithmetic Shift Left (uses same logic so normally combined with ASHIFTRIGHT and LSHIFTRIGHT).
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constant IMPL_EVOM_ASHIFTRIGHT : boolean := false; -- Arithmetic Shift Right.
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constant IMPL_EVOM_CALL : boolean := false; -- Call to direct address.
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constant IMPL_EVOM_CALLPCREL : boolean := false; -- Call to indirect address (add offset to program counter).
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constant IMPL_EVOM_DIV : boolean := false; -- 32bit signed division.
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constant IMPL_EVOM_EQ : boolean := false; -- Equality test.
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constant IMPL_EVOM_EXTENDED_INSN : boolean := false; -- Extended multibyte instruction set.
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constant IMPL_EVOM_FIADD32 : boolean := false; -- Fixed point Q17.15 addition.
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constant IMPL_EVOM_FIDIV32 : boolean := false; -- Fixed point Q17.15 division.
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constant IMPL_EVOM_FIMULT32 : boolean := false; -- Fixed point Q17.15 multiplication.
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constant IMPL_EVOM_LOADB : boolean := false; -- Load single byte from memory.
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constant IMPL_EVOM_LOADH : boolean := false; -- Load half word (16bit) from memory.
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constant IMPL_EVOM_LSHIFTRIGHT : boolean := false; -- Logical shift right.
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constant IMPL_EVOM_MOD : boolean := false; -- 32bit modulo (remainder after division).
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constant IMPL_EVOM_MULT : boolean := false; -- 32bit signed multiplication.
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constant IMPL_EVOM_NEG : boolean := false; -- Negate value in TOS.
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constant IMPL_EVOM_NEQ : boolean := false; -- Not equal test.
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constant IMPL_EVOM_POPPCREL : boolean := false; -- Pop a value into the Program Counter from a location relative to the Stack Pointer.
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constant IMPL_EVOM_PUSHSPADD : boolean := false; -- Add a value to the Stack pointer and push it onto the stack.
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constant IMPL_EVOM_STOREB : boolean := false; -- Store/Write a single byte to memory/IO.
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constant IMPL_EVOM_STOREH : boolean := false; -- Store/Write a half word (16bit) to memory/IO.
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constant IMPL_EVOM_SUB : boolean := false; -- 32bit signed subtract.
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constant IMPL_EVOM_XOR : boolean := false; -- Exclusive or of value in TOS.
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-- Ranges used throughout the SOC source.
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subtype ADDR_BIT_BRAM_RANGE is natural range SOC_MAX_ADDR_BRAM_BIT-1 downto 0; -- Address range of the onboard B(lock)RAM - 1 byte aligned
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subtype ADDR_BIT_BRAM_16BIT_RANGE is natural range SOC_MAX_ADDR_BRAM_BIT-1 downto 1; -- Address range of the onboard B(lock)RAM - 2 bytes aligned
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subtype ADDR_BIT_BRAM_32BIT_RANGE is natural range SOC_MAX_ADDR_BRAM_BIT-1 downto minAddrBit; -- Address range of the onboard B(lock)RAM - 4 bytes aligned
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subtype ADDR_BIT_RAM_RANGE is natural range SOC_MAX_ADDR_RAM_BIT-1 downto 0; -- Address range of external RAM (BRAM, Dynamic, Static etc) - 1 byte aligned
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subtype ADDR_BIT_RAM_16BIT_RANGE is natural range SOC_MAX_ADDR_RAM_BIT-1 downto 1; -- Address range of external RAM (BRAM, Dynamic, Static etc) - 2 bytes aligned
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subtype ADDR_BIT_RAM_32BIT_RANGE is natural range SOC_MAX_ADDR_RAM_BIT-1 downto minAddrBit; -- Address range of external RAM (BRAM, Dynamic, Static etc) - 4 bytes aligned
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subtype ADDR_BIT_SDRAM_RANGE is natural range SOC_MAX_ADDR_SDRAM_BIT-1 downto 0; -- Address range of external RAM (BRAM, Dynamic, Static etc) - 1 byte aligned
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subtype ADDR_BIT_SDRAM_16BIT_RANGE is natural range SOC_MAX_ADDR_SDRAM_BIT-1 downto 1; -- Address range of external RAM (BRAM, Dynamic, Static etc) - 2 bytes aligned
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subtype ADDR_BIT_SDRAM_32BIT_RANGE is natural range SOC_MAX_ADDR_SDRAM_BIT-1 downto minAddrBit; -- Address range of external RAM (BRAM, Dynamic, Static etc) - 4 bytes aligned
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subtype ADDR_BIT_WB_SDRAM_RANGE is natural range SOC_MAX_ADDR_WB_SDRAM_BIT-1 downto 0; -- Address range of external RAM (BRAM, Dynamic, Static etc) - 1 byte aligned
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subtype ADDR_BIT_WB_SDRAM_16BIT_RANGE is natural range SOC_MAX_ADDR_WB_SDRAM_BIT-1 downto 1; -- Address range of external RAM (BRAM, Dynamic, Static etc) - 2 bytes aligned
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subtype ADDR_BIT_WB_SDRAM_32BIT_RANGE is natural range SOC_MAX_ADDR_WB_SDRAM_BIT-1 downto minAddrBit; -- Address range of external RAM (BRAM, Dynamic, Static etc) - 4 bytes aligned
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-- subtype ADDR_DECODE_BRAM_RANGE is natural range maxAddrBit-1 downto SOC_MAX_ADDR_BRAM_BIT; -- Decode range for selection of the BRAM within the address space.
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-- subtype ADDR_DECODE_RAM_RANGE is natural range maxAddrBit-1 downto SOC_MAX_ADDR_RAM_BIT; -- Decode range for selection of the RAM within the address space.
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subtype IO_DECODE_RANGE is natural range maxAddrBit-WB_ACTIVE-1 downto maxIOBit; -- Upper bits in memory defining the IO block within the address space for the EVO cpu IO. All other models use ioBit.
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-- subtype WB_IO_DECODE_RANGE is natural range maxAddrBit-1 downto maxIOBit; -- Upper bits in memory defining the IO block within the address space for the EVO cpu IO. All other models use ioBit.
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-- Device options
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type CardType_t is (SD_CARD_E, SDHC_CARD_E); -- Define the different types of SD cards.
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------------------------------------------------------------
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-- Constants
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------------------------------------------------------------
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constant YES : std_logic := '1';
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constant NO : std_logic := '0';
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constant HI : std_logic := '1';
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constant LO : std_logic := '0';
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constant ONE : std_logic := '1';
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constant ZERO : std_logic := '0';
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constant HIZ : std_logic := 'Z';
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------------------------------------------------------------
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-- Function prototypes
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------------------------------------------------------------
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-- Find the maximum of two integers.
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function IntMax(a : in integer; b : in integer) return integer;
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-- Find the number of bits required to represent an integer.
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function log2ceil(arg : positive) return natural;
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------------------------------------------------------------
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-- Records
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------------------------------------------------------------
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------------------------------------------------------------
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-- Components
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------------------------------------------------------------
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component dualport_ram is
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port (
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clk : in std_logic;
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memAWriteEnable : in std_logic;
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memAAddr : in std_logic_vector(ADDR_32BIT_RANGE);
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memAWrite : in std_logic_vector(WORD_32BIT_RANGE);
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memARead : out std_logic_vector(WORD_32BIT_RANGE);
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memBWriteEnable : in std_logic;
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memBAddr : in std_logic_vector(ADDR_32BIT_RANGE);
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memBWrite : in std_logic_vector(WORD_32BIT_RANGE);
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memBRead : out std_logic_vector(WORD_32BIT_RANGE)
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);
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end component;
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component dpram
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generic (
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init_file : string;
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widthad_a : natural;
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width_a : natural;
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widthad_b : natural;
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width_b : natural;
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outdata_reg_a : string := "UNREGISTERED";
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outdata_reg_b : string := "UNREGISTERED"
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);
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port (
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clock_a : in std_logic := '1';
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clocken_a : in std_logic := '1';
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address_a : in std_logic_vector (widthad_a-1 downto 0);
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data_a : in std_logic_vector (width_a-1 downto 0);
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wren_a : in std_logic := '0';
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q_a : out std_logic_vector (width_a-1 downto 0);
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clock_b : in std_logic;
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clocken_b : in std_logic := '1';
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address_b : in std_logic_vector (widthad_b-1 downto 0);
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data_b : in std_logic_vector (width_b-1 downto 0);
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wren_b : in std_logic := '0';
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q_b : out std_logic_vector (width_b-1 downto 0)
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);
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end component;
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component SDCard is
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generic (
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FREQ_G : real := 100.0; -- Master clock frequency (MHz).
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INIT_SPI_FREQ_G : real := 0.4; -- Slow SPI clock freq. during initialization (MHz).
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SPI_FREQ_G : real := 25.0; -- Operational SPI freq. to the SD card (MHz).
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BLOCK_SIZE_G : natural := 512; -- Number of bytes in an SD card block or sector.
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CARD_TYPE_G : CardType_t := SD_CARD_E -- Type of SD card connected to this controller.
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);
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port (
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-- Host-side interface signals.
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clk_i : in std_logic; -- Master clock.
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reset_i : in std_logic := NO; -- active-high, synchronous reset.
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rd_i : in std_logic := NO; -- active-high read block request.
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wr_i : in std_logic := NO; -- active-high write block request.
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continue_i : in std_logic := NO; -- If true, inc address and continue R/W.
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addr_i : in std_logic_vector(31 downto 0) := x"00000000"; -- Block address.
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data_i : in std_logic_vector(7 downto 0) := x"00"; -- Data to write to block.
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data_o : out std_logic_vector(7 downto 0) := x"00"; -- Data read from block.
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busy_o : out std_logic; -- High when controller is busy performing some operation.
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hndShk_i : in std_logic; -- High when host has data to give or has taken data.
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hndShk_o : out std_logic; -- High when controller has taken data or has data to give.
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error_o : out std_logic_vector(15 downto 0) := (others => NO);
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-- I/O signals to the external SD card.
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cs_bo : out std_logic := HI; -- Active-low chip-select.
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sclk_o : out std_logic := LO; -- Serial clock to SD card.
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mosi_o : out std_logic := HI; -- Serial data output to SD card.
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miso_i : in std_logic := ZERO -- Serial data input from SD card.
|
|
);
|
|
end component;
|
|
|
|
end zpu_soc_pkg;
|
|
|
|
------------------------------------------------------------
|
|
-- Function definitions.
|
|
------------------------------------------------------------
|
|
package body zpu_soc_pkg is
|
|
|
|
-- Find the maximum of two integers.
|
|
function IntMax(a : in integer; b : in integer) return integer is
|
|
begin
|
|
if a > b then
|
|
return a;
|
|
else
|
|
return b;
|
|
end if;
|
|
return a;
|
|
end function IntMax;
|
|
|
|
-- Find the number of bits required to represent an integer.
|
|
function log2ceil(arg : positive) return natural is
|
|
variable tmp : positive := 1;
|
|
variable log : natural := 0;
|
|
begin
|
|
if arg = 1 then
|
|
return 0;
|
|
end if;
|
|
|
|
while arg > tmp loop
|
|
tmp := tmp * 2;
|
|
log := log + 1;
|
|
end loop;
|
|
return log;
|
|
end function;
|
|
|
|
end package body;
|