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rocket-chip/scripts/vlsi_mem_gen

196 lines
7.2 KiB
Python
Executable File

#! /usr/bin/env python
# See LICENSE.SiFive for license details.
# See LICENSE.Berkeley for license details.
import sys
import math
use_latches = 0
def parse_line(line):
name = ''
width = 0
depth = 0
ports = ''
mask_gran = 0
tokens = line.split()
i = 0
for i in range(0,len(tokens),2):
s = tokens[i]
if s == 'name':
name = tokens[i+1]
elif s == 'width':
width = int(tokens[i+1])
mask_gran = width # default setting
elif s == 'depth':
depth = int(tokens[i+1])
elif s == 'ports':
ports = tokens[i+1].split(',')
elif s == 'mask_gran':
mask_gran = int(tokens[i+1])
else:
sys.exit('%s: unknown argument %s' % (sys.argv[0], a))
return (name, width, depth, mask_gran, width//mask_gran, ports)
def gen_mem(name, width, depth, mask_gran, mask_seg, ports):
addr_width = max(math.ceil(math.log(depth)/math.log(2)),1)
port_spec = []
readports = []
writeports = []
latchports = []
rwports = []
decl = []
combinational = []
sequential = []
maskedports = {}
for pid in range(len(ports)):
ptype = ports[pid]
if ptype[0:1] == 'm':
ptype = ptype[1:]
maskedports[pid] = pid
if ptype == 'read':
prefix = 'R%d_' % len(readports)
port_spec.append('input %sclk' % prefix)
port_spec.append('input [%d:0] %saddr' % (addr_width-1, prefix))
port_spec.append('input %sen' % prefix)
port_spec.append('output [%d:0] %sdata' % (width-1, prefix))
readports.append(pid)
elif ptype == 'write':
prefix = 'W%d_' % len(writeports)
port_spec.append('input %sclk' % prefix)
port_spec.append('input [%d:0] %saddr' % (addr_width-1, prefix))
port_spec.append('input %sen' % prefix)
port_spec.append('input [%d:0] %sdata' % (width-1, prefix))
if pid in maskedports:
port_spec.append('input [%d:0] %smask' % (mask_seg-1, prefix))
if not use_latches or pid in maskedports:
writeports.append(pid)
else:
latchports.append(pid)
elif ptype == 'rw':
prefix = 'RW%d_' % len(rwports)
port_spec.append('input %sclk' % prefix)
port_spec.append('input [%d:0] %saddr' % (addr_width-1, prefix))
port_spec.append('input %sen' % prefix)
port_spec.append('input %swmode' % prefix)
if pid in maskedports:
port_spec.append('input [%d:0] %swmask' % (mask_seg-1, prefix))
port_spec.append('input [%d:0] %swdata' % (width-1, prefix))
port_spec.append('output [%d:0] %srdata' % (width-1, prefix))
rwports.append(pid)
else:
sys.exit('%s: unknown port type %s' % (sys.argv[0], ptype))
nr = len(readports)
nw = len(writeports)
nrw = len(rwports)
masked = len(maskedports)>0
tup = (depth, width, nr, nw, nrw, masked)
def emit_read(idx, rw):
prefix = ('RW%d_' if rw else 'R%d_') % idx
data = ('%srdata' if rw else '%sdata') % prefix
en = ('%sen && !%swmode' % (prefix, prefix)) if rw else ('%sen' % prefix)
decl.append('reg reg_%sren;' % prefix)
decl.append('reg [%d:0] reg_%saddr;' % (addr_width-1, prefix))
sequential.append('always @(posedge %sclk)' % prefix)
sequential.append(' reg_%sren <= %s;' % (prefix, en))
sequential.append('always @(posedge %sclk)' % prefix)
sequential.append(' if (%s) reg_%saddr <= %saddr;' % (en, prefix, prefix))
combinational.append('`ifdef RANDOMIZE_GARBAGE_ASSIGN')
combinational.append('reg [%d:0] %srandom;' % (((width-1)//32+1)*32-1, prefix))
combinational.append('`ifdef RANDOMIZE_MEM_INIT')
combinational.append(' initial begin')
combinational.append(' #0.002 begin end')
combinational.append(' %srandom = {%s};' % (prefix, ', '.join(['$random'] * ((width-1)//32+1))))
combinational.append(' reg_%sren = %srandom[0];' % (prefix, prefix))
combinational.append(' end')
combinational.append('`endif')
combinational.append('always @(posedge %sclk) %srandom <= {%s};' % (prefix, prefix, ', '.join(['$random'] * ((width-1)//32+1))))
combinational.append('assign %s = reg_%sren ? ram[reg_%saddr] : %srandom[%d:0];' % (data, prefix, prefix, prefix, width-1))
combinational.append('`else')
combinational.append('assign %s = ram[reg_%saddr];' % (data, prefix))
combinational.append('`endif')
for idx in range(nr):
emit_read(idx, False)
for idx in range(nrw):
emit_read(idx, True)
for idx in range(len(latchports)):
prefix = 'W%d_' % idx
decl.append('reg [%d:0] latch_%saddr;' % (addr_width-1, prefix))
decl.append('reg [%d:0] latch_%sdata;' % (width-1, prefix))
decl.append('reg latch_%sen;' % (prefix))
combinational.append('always @(*) begin')
combinational.append(' if (!%sclk && %sen) latch_%saddr <= %saddr;' % (prefix, prefix, prefix, prefix))
combinational.append(' if (!%sclk && %sen) latch_%sdata <= %sdata;' % (prefix, prefix, prefix, prefix))
combinational.append(' if (!%sclk) latch_%sen <= %sen;' % (prefix, prefix, prefix))
combinational.append('end')
combinational.append('always @(*)')
combinational.append(' if (%sclk && latch_%sen)' % (prefix, prefix))
combinational.append(' ram[latch_%saddr] <= latch_%sdata;' % (prefix, prefix))
decl.append('reg [%d:0] ram [%d:0];' % (width-1, depth-1))
decl.append('`ifdef RANDOMIZE_MEM_INIT')
decl.append(' integer initvar;')
decl.append(' initial begin')
decl.append(' #0.002 begin end')
decl.append(' for (initvar = 0; initvar < %d; initvar = initvar+1)' % depth)
decl.append(' ram[initvar] = {%d {$random}};' % ((width-1)//32+1))
for idx in range(nr):
prefix = 'R%d_' % idx
decl.append(' reg_%saddr = {%d {$random}};' % (prefix, ((addr_width-1)//32+1)))
for idx in range(nrw):
prefix = 'RW%d_' % idx
decl.append(' reg_%saddr = {%d {$random}};' % (prefix, ((addr_width-1)//32+1)))
decl.append(' end')
decl.append('`endif')
decl.append("integer i;")
for idx in range(nw):
prefix = 'W%d_' % idx
pid = writeports[idx]
sequential.append('always @(posedge %sclk)' % prefix)
sequential.append(" if (%sen) begin" % prefix)
for i in range(mask_seg):
mask = ('if (%smask[%d]) ' % (prefix, i)) if pid in maskedports else ''
ram_range = '%d:%d' % ((i+1)*mask_gran-1, i*mask_gran)
sequential.append(" %sram[%saddr][%s] <= %sdata[%s];" % (mask, prefix, ram_range, prefix, ram_range))
sequential.append(" end")
for idx in range(nrw):
pid = rwports[idx]
prefix = 'RW%d_' % idx
sequential.append('always @(posedge %sclk)' % prefix)
sequential.append(" if (%sen && %swmode) begin" % (prefix, prefix))
for i in range(mask_seg):
mask = ('if (%swmask[%d]) ' % (prefix, i)) if pid in maskedports else ''
ram_range = '%d:%d' % ((i+1)*mask_gran-1, i*mask_gran)
sequential.append(" %sram[%saddr][%s] <= %swdata[%s];" % (mask, prefix, ram_range, prefix, ram_range))
sequential.append(" end")
body = "\
%s\n\
%s\n\
%s\n" % ('\n '.join(decl), '\n '.join(sequential), '\n '.join(combinational))
s = "\nmodule %s(\n\
%s\n\
);\n\
\n\
%s\
\n\
endmodule" % (name, ',\n '.join(port_spec), body)
return s
def main():
if len(sys.argv) < 2:
sys.exit('Please give a .conf file as input')
for line in open(sys.argv[1]):
print(gen_mem(*parse_line(line)))
if __name__ == '__main__':
main()