diff --git a/tb/lasmicon/lasmicon.py b/tb/lasmicon/lasmicon.py
index 691569380..7ce009a05 100644
--- a/tb/lasmicon/lasmicon.py
+++ b/tb/lasmicon/lasmicon.py
@@ -27,11 +27,12 @@ def my_generator(n):
 class TB(Module):
 	def __init__(self):
 		self.submodules.dut = LASMIcon(sdram_phy, sdram_geom, sdram_timing)
-		self.submodules.xbar = lasmibus.Crossbar([self.dut.lasmic], 6, self.dut.nrowbits)
+		self.submodules.xbar = lasmibus.Crossbar([self.dut.lasmic], self.dut.nrowbits)
 		self.submodules.logger = DFILogger(self.dut.dfi)
 
+		masters = [self.xbar.get_master() for i in range(6)]
 		self.initiators = [Initiator(my_generator(n), master)
-			for n, master in enumerate(self.xbar.masters)]
+			for n, master in enumerate(masters)]
 		self.submodules += self.initiators
 
 	def do_simulation(self, s):
diff --git a/tb/lasmicon/lasmicon_df.py b/tb/lasmicon/lasmicon_df.py
index c34c8fad4..512c94249 100644
--- a/tb/lasmicon/lasmicon_df.py
+++ b/tb/lasmicon/lasmicon_df.py
@@ -10,10 +10,10 @@ from common import sdram_phy, sdram_geom, sdram_timing, DFILogger
 class TB(Module):
 	def __init__(self):
 		self.submodules.ctler = LASMIcon(sdram_phy, sdram_geom, sdram_timing)
-		# FIXME: remove dummy master
-		self.submodules.xbar = lasmibus.Crossbar([self.ctler.lasmic], 2, self.ctler.nrowbits)
+		self.submodules.xbar = lasmibus.Crossbar([self.ctler.lasmic], self.ctler.nrowbits)
+		self.xbar.get_master() # FIXME: remove dummy master
 		self.submodules.logger = DFILogger(self.ctler.dfi)
-		self.submodules.writer = dma_lasmi.Writer(self.xbar.masters[0])
+		self.submodules.writer = dma_lasmi.Writer(self.xbar.get_master())
 
 		self.comb += self.writer.address_data.stb.eq(1)
 		pl = self.writer.address_data.payload
diff --git a/tb/lasmicon/lasmicon_wb.py b/tb/lasmicon/lasmicon_wb.py
index ad2f429bc..89b5fa334 100644
--- a/tb/lasmicon/lasmicon_wb.py
+++ b/tb/lasmicon/lasmicon_wb.py
@@ -26,10 +26,10 @@ def my_generator():
 class TB(Module):
 	def __init__(self):
 		self.submodules.ctler = LASMIcon(sdram_phy, sdram_geom, sdram_timing)
-		# FIXME: remove dummy master
-		self.submodules.xbar = lasmibus.Crossbar([self.ctler.lasmic], 2, self.ctler.nrowbits)
+		self.submodules.xbar = lasmibus.Crossbar([self.ctler.lasmic], self.ctler.nrowbits)
+		self.xbar.get_master() # FIXME: remove dummy master
 		self.submodules.logger = DFILogger(self.ctler.dfi)
-		self.submodules.bridge = wishbone2lasmi.WB2LASMI(l2_size//4, self.xbar.masters[0])
+		self.submodules.bridge = wishbone2lasmi.WB2LASMI(l2_size//4, self.xbar.get_master())
 		self.submodules.initiator = wishbone.Initiator(my_generator())
 		self.submodules.conn = wishbone.InterconnectPointToPoint(self.initiator.bus, self.bridge.wishbone)
 
diff --git a/top.py b/top.py
index 321b87c89..50a6502be 100644
--- a/top.py
+++ b/top.py
@@ -105,24 +105,14 @@ class SoC(Module):
 		self.submodules.lasmicon = lasmicon.LASMIcon(self.ddrphy.phy_settings, sdram_geom, sdram_timing)
 		self.submodules.dficon1 = dfi.Interconnect(self.lasmicon.dfi, self.dfii.slave)
 
-		n_lasmims = 1 # wishbone bridging
+		self.submodules.lasmixbar = lasmibus.Crossbar([self.lasmicon.lasmic], self.lasmicon.nrowbits)
+		lasmim_wb = self.lasmixbar.get_master()
 		if platform_name == "mixxeo":
-			n_lasmims += 4 # framebuffer (2-channel mixing) + 2 DVI samplers
+			lasmim_fb0, lasmim_fb1, lasmim_dvi0, lasmim_dvi1 = (self.lasmixbar.get_master() for i in range(4))
 		if platform_name == "m1":
-			n_lasmims += 1 # framebuffer (single channel)
+			lasmim_fb = self.lasmixbar.get_master()
 		if with_memtest:
-			n_lasmims += 2 # writer + reader
-		self.submodules.lasmixbar = lasmibus.Crossbar([self.lasmicon.lasmic], n_lasmims, self.lasmicon.nrowbits)
-
-		lasmims = list(self.lasmixbar.masters)
-		lasmim_wb = lasmims.pop()
-		if platform_name == "mixxeo":
-			lasmim_fb0, lasmim_fb1, lasmim_dvi0, lasmim_dvi1 = (lasmims.pop() for i in range(4))
-		if platform_name == "m1":
-			lasmim_fb = lasmims.pop()
-		if with_memtest:
-			lasmim_mtw, lasmim_mtr = lasmims.pop(), lasmims.pop()
-		assert(not lasmims)
+			lasmim_mtw, lasmim_mtr = self.lasmixbar.get_master(), self.lasmixbar.get_master()
 
 		#
 		# WISHBONE