Use Wishbone SRAM component from Migen

milkymist/sram/__init__.py

@@ -1,29 +0,0 @@
-from migen.fhdl.structure import *
-from migen.bus import wishbone
-
-class SRAM:
-	def __init__(self, depth):
-		self.bus = wishbone.Interface()
-		self.depth = depth
-	
-	def get_fragment(self):
-		# memory
-		mem = Memory(32, self.depth)
-		port = mem.get_port(write_capable=True, we_granularity=8)
-		# generate write enable signal
-		comb = [port.we[i].eq(self.bus.cyc & self.bus.stb & self.bus.we & self.bus.sel[i])
-			for i in range(4)]
-		# address and data
-		comb += [
-			port.adr.eq(self.bus.adr[:len(port.adr)]),
-			port.dat_w.eq(self.bus.dat_w),
-			self.bus.dat_r.eq(port.dat_r)
-		]
-		# generate ack
-		sync = [
-			self.bus.ack.eq(0),
-			If(self.bus.cyc & self.bus.stb & ~self.bus.ack,
-				self.bus.ack.eq(1)
-			)
-		]
-		return Fragment(comb, sync, memories=[mem])

top.py

@@ -5,7 +5,7 @@ from migen.fhdl.structure import *
 from migen.fhdl import verilog, autofragment
 from migen.bus import wishbone, wishbone2asmi, csr, wishbone2csr, dfi
 
-from milkymist import m1crg, lm32, norflash, uart, sram, s6ddrphy, dfii, asmicon, \
+from milkymist import m1crg, lm32, norflash, uart, s6ddrphy, dfii, asmicon, \
 	identifier, timer, minimac3, framebuffer, asmiprobe
 from cmacros import get_macros
 from constraints import Constraints
@@ -81,7 +81,7 @@ def get():
 	#
 	cpu0 = lm32.LM32()
 	norflash0 = norflash.NorFlash(25, 12)
-	sram0 = sram.SRAM(sram_size//4)
+	sram0 = wishbone.SRAM(sram_size)
 	minimac0 = minimac3.MiniMAC(csr_offset("MINIMAC"))
 	wishbone2asmi0 = wishbone2asmi.WB2ASMI(l2_size//4, asmiport_wb)
 	wishbone2csr0 = wishbone2csr.WB2CSR()