diff --git a/ztex_21x_common.py b/ztex_21x_common.py
new file mode 100644
index 0000000..8334e6f
--- /dev/null
+++ b/ztex_21x_common.py
@@ -0,0 +1,118 @@
+#
+# Copyright (c) 2015 Yann Sionneau <yann.sionneau@gmail.com>
+# Copyright (c) 2015-2019 Florent Kermarrec <florent@enjoy-digital.fr>
+# Copyright (c) 2020-2021 Romain Dolbeau <romain@dolbeau.org>
+# SPDX-License-Identifier: BSD-2-Clause
+
+from litex.build.generic_platform import *
+from litex.build.xilinx import XilinxPlatform
+from litex.build.openocd import OpenOCD
+
+# IOs ----------------------------------------------------------------------------------------------
+
+# FPGA daughterboard I/O
+
+_io = [
+    ## 48 MHz clock reference
+    ("clk48", 0, Pins("P15"), IOStandard("LVCMOS33")),
+    ## embedded 256 MiB DDR3 DRAM
+    ("ddram", 0,
+        Subsignal("a", Pins("C5 B6 C7 D5 A3 E7 A4 C6", "A6 D8 B2 A5 B3 B7"),
+            IOStandard("SSTL135")),
+        Subsignal("ba",    Pins("E5 A1 E6"), IOStandard("SSTL135")),
+        Subsignal("ras_n", Pins("E3"), IOStandard("SSTL135")),
+        Subsignal("cas_n", Pins("D3"), IOStandard("SSTL135")),
+        Subsignal("we_n",  Pins("D4"), IOStandard("SSTL135")),
+#        Subsignal("cs_n",  Pins(""), IOStandard("SSTL135")),
+        Subsignal("dm", Pins("G1 G6"), IOStandard("SSTL135")),
+        Subsignal("dq", Pins(
+            "H1 F1 E2 E1 F4 C1 F3 D2",
+            "G4 H5 G3 H6 J2 J3 K1 K2"),
+            IOStandard("SSTL135"),
+            Misc("IN_TERM=UNTUNED_SPLIT_40")),
+        Subsignal("dqs_p", Pins("H2 J4"),
+            IOStandard("DIFF_SSTL135"),
+            Misc("IN_TERM=UNTUNED_SPLIT_40")),
+        Subsignal("dqs_n", Pins("G2 H4"),
+            IOStandard("DIFF_SSTL135"),
+            Misc("IN_TERM=UNTUNED_SPLIT_40")),
+        Subsignal("clk_p", Pins("C4"), IOStandard("DIFF_SSTL135")),
+        Subsignal("clk_n", Pins("B4"), IOStandard("DIFF_SSTL135")),
+        Subsignal("cke",   Pins("B1"), IOStandard("SSTL135")),
+        Subsignal("odt",   Pins("F5"), IOStandard("SSTL135")),
+        Subsignal("reset_n", Pins("J5"), IOStandard("SSTL135")),
+        Misc("SLEW=FAST"),
+    ),
+]
+
+_flash_io_2_13 = [
+    ("config_spiflash", 0,
+        Subsignal("cs_n", Pins("L13")),
+        # Subsignal("clk",  Pins("E9")), # 'E9' isn't a user pin, access clock via STARTUPE2 primitive, disabling the pads should do it in LiteSPIClkGen ?
+        Subsignal("mosi", Pins("K17")),
+        Subsignal("miso", Pins("K18")),
+        IOStandard("LVCMOS33"),
+    ),
+]
+_flash_io_2_12 = [
+    ("config_spiflash", 0,
+        Subsignal("cs_n", Pins("L13")),
+        # Subsignal("clk",  Pins("E9")), # 'E9' isn't a user pin, access clock via STARTUPE2 primitive, disabling the pads should do it in LiteSPIClkGen ?
+        Subsignal("mosi", Pins("K17")),
+        Subsignal("miso", Pins("K18")),
+        IOStandard("LVCMOS33"),
+    ),
+    ("fx2_sloe", 0, Pins("T14"), IOStandard("LVCMOS33")),
+]
+
+class ZTexPlatform(XilinxPlatform):
+    default_clk_name   = "clk48"
+    default_clk_period = 1e9/48e6
+
+    def __init__(self, variant="ztex2.13a", version="V1.0", connectors=None):
+        device = {
+            "ztex2.12a":  "xc7a15tcsg324-1", #untested, too small?
+            "ztex2.12b":  "xc7a35tcsg324-1",
+            "ztex2.13a":  "xc7a35tcsg324-1",
+            "ztex2.13b":  "xc7a50tcsg324-1", #untested
+            "ztex2.13b2": "xc7a50tcsg324-1", #untested
+            "ztex2.13c":  "xc7a75tcsg324-2", #untested
+            "ztex2.13d":  "xc7a100tcsg324-2" #untested
+        }[variant]
+        flash_io = {
+            "ztex2.12a":  _flash_io_2_12,
+            "ztex2.12b":  _flash_io_2_12,
+            "ztex2.13a":  _flash_io_2_13,
+            "ztex2.13b":  _flash_io_2_13,
+            "ztex2.13b2": _flash_io_2_13,
+            "ztex2.13c":  _flash_io_2_13,
+            "ztex2.13d":  _flash_io_2_13,
+        }[variant]
+        
+        self.speedgrade = -1
+        if (device[-1] == '2'):
+            self.speedgrade = -2
+        
+        XilinxPlatform.__init__(self, device, _io, connectors, toolchain="vivado")
+        
+        self.add_extension(flash_io)
+        
+        self.toolchain.bitstream_commands = \
+            ["set_property BITSTREAM.CONFIG.SPI_32BIT_ADDR No [current_design]",
+             "set_property BITSTREAM.CONFIG.SPI_BUSWIDTH 2 [current_design]",
+             "set_property BITSTREAM.CONFIG.CONFIGRATE 66 [current_design]",
+             "set_property BITSTREAM.GENERAL.COMPRESS true [current_design]",
+             "set_property BITSTREAM.GENERAL.CRC DISABLE [current_design]",
+             "set_property STEPS.SYNTH_DESIGN.ARGS.RETIMING true [get_runs synth_1]",
+             "set_property CONFIG_VOLTAGE 3.3 [current_design]",
+             "set_property CFGBVS VCCO [current_design]"
+#             , "set_property STEPS.SYNTH_DESIGN.ARGS.DIRECTIVE AreaOptimized_high [get_runs synth_1]"
+             ]
+
+    def create_programmer(self):
+        bscan_spi = "bscan_spi_xc7a35t.bit"
+        return OpenOCD("openocd_xc7_ft2232.cfg", bscan_spi) #FIXME
+
+    def do_finalize(self, fragment):
+        XilinxPlatform.do_finalize(self, fragment)
+        #self.add_period_constraint(self.lookup_request("clk48", loose=True), 1e9/48e6)