bkram.txt

################################################################################
##
## Filename:	auto-data/bkram.txt
##
## Project:	AutoFPGA, a utility for composing FPGA designs from peripherals
## {{{
## Purpose:	To define the interface to a generic block RAM device for the
##		purposes of autofpga.
##
## Creator:	Dan Gisselquist, Ph.D.
##		Gisselquist Technology, LLC
##
################################################################################
## }}}
## Copyright (C) 2017-2024, Gisselquist Technology, LLC
## {{{
## This program is free software (firmware): you can redistribute it and/or
## modify it under the terms of the GNU General Public License as published
## by the Free Software Foundation, either version 3 of the License, or (at
## your option) any later version.
##
## This program is distributed in the hope that it will be useful, but WITHOUT
## ANY WARRANTY; without even the implied warranty of MERCHANTIBILITY or
## FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
## for more details.
##
## You should have received a copy of the GNU General Public License along
## with this program.  (It's in the $(ROOT)/doc directory.  Run make with no
## target there if the PDF file isn't present.)  If not, see
## <http://www.gnu.org/licenses/> for a copy.
## }}}
## License:	GPL, v3, as defined and found on www.gnu.org,
## {{{
##		http://www.gnu.org/licenses/gpl.html
##
##
################################################################################
##
## }}}
@PREFIX=bkram
@DEVID=BKRAM
@$LGMEMSZ=20
@LGMEMSZ.FORMAT=%d
@$NADDR=(1<<(@$(THIS.LGMEMSZ)))/(@$(SLAVE.BUS.WIDTH)/8)
@$NBYTES=(1<<(@$THIS.LGMEMSZ))
@NBYTES.FORMAT=0x%08x
@ACCESS=@$(DEVID)_ACCESS
@SLAVE.TYPE=MEMORY
@SLAVE.BUS=wbwide
@MAIN.INSERT=
	memdev #(
		.LGMEMSZ(@$(THIS.LGMEMSZ)),
		.DW(@$(SLAVE.BUS.WIDTH)),
		.EXTRACLOCK(1)
	) u_@$(PREFIX) (
		.i_clk(@$(SLAVE.BUS.CLOCK.WIRE)),
		.i_reset(@$(SLAVE.BUS.CLOCK.RESET)),
		@$(SLAVE.ANSIPORTLIST)
	);
@REGS.N=1
@REGS.0= 0 R_@$(DEVID) RAM
@REGDEFS.H.DEFNS=
#define	@$(DEVID)BASE	@$[0x%08x](REGBASE)
#define	@$(DEVID)LEN	@$NBYTES
@BDEF.OSDEF=_BOARD_HAS_@$(DEVID)
@MEM.NAME= @$(PREFIX)
@BDEF.OSVAL=extern char	_@$(MEM.NAME)[@$NBYTES];
@LD.PERM=	wx
@LD.NAME=	@$(MEM.NAME)
@RTL.MAKE.GROUP= @$(DEVID)
@RTL.MAKE.SUBD=
@RTL.MAKE.FILES= memdev.v
@$NADDRHX = @$NADDR
@NADDRHX.FORMAT= 0x%x
@SIM.INCLUDE=
#include "byteswap.h"
@SIM.DEFINES=
#ifndef VVAR
#ifdef  ROOT_VERILATOR
#include "Vmain___024root.h"

#define VVAR(A) rootp->main__DOT_ ## A
#elif	defined(NEW_VERILATOR)
#define VVAR(A) main__DOT_ ## A
#else
#define VVAR(A) v__DOT_ ## A
#endif
#endif

#define	block_ram	rootp->main__DOT__u_@$(PREFIX)__DOT__mem.m_storage

@$BUSBYTES=@$(SLAVE.BUS.WIDTH)/8
@SLAVE.ORDER=1
@SIM.LOAD=
			start = start & (-4);
			wlen = (wlen+3)&(-4);

			// Need to byte swap data to get it into the memory
			if (@$(SLAVE.BUS.WIDTH) == 32) {
				char	*bswapd = new char[len+8];
				memcpy(bswapd, &buf[offset], wlen);
				byteswapbuf(len>>2, (uint32_t *)bswapd);
				memcpy(&m_core->block_ram[start], bswapd, wlen);
				delete[] bswapd;
			} else {
				for(unsigned jk=0; jk<wlen; jk=jk+1) {
					unsigned word_addr, subword_addr;
					unsigned	*wp;
					char		*cp;

					word_addr = start+jk;
					word_addr /= @$(SLAVE.BUS.WIDTH)/8;
					wp = m_core->block_ram[word_addr];
					cp = (char *)wp;

					subword_addr = start+jk;
					subword_addr = ~subword_addr;
					subword_addr &= @$(SLAVE.BUS.WIDTH)/8-1;
					// subword_addr = @$(SLAVE.BUS.WIDTH)/8-subword_addr;
					cp[subword_addr] = buf[offset+jk];
				}
			}