gsd_butterstick: Add optional SYZYGY GPIO (--with-syzygy-gpio) to expose the 32 GPIOs on SYZYGY breakout board.

litex_boards/platforms/gsd_butterstick.py

@@ -175,6 +175,11 @@ _connectors_r1_0 = [
     ),
 ]
 
+# SYZYGY -------------------------------------------------------------------------------------------
+
+def raw_syzygy_io(syzygy, iostandard="LVCMOS33"):
+    return [(syzygy, 0, Pins(" ".join([f"{syzygy}:S{i:d}" for i in range(32)])), IOStandard(iostandard))]
+
 # Platform -----------------------------------------------------------------------------------------
 
 class Platform(LatticePlatform):

litex_boards/targets/gsd_butterstick.py

@@ -27,6 +27,7 @@ from litex.soc.cores.clock import *
 from litex.soc.integration.soc_core import *
 from litex.soc.integration.builder import *
 from litex.soc.cores.led import LedChaser
+from litex.soc.cores.gpio import GPIOTristate
 
 from litedram.modules import MT41K64M16,MT41K128M16,MT41K256M16,MT41K512M16
 from litedram.phy import ECP5DDRPHY
@@ -89,6 +90,7 @@ class BaseSoC(SoCCore):
         eth_dynamic_ip   = False,
         with_spi_flash   = False,
         with_led_chaser  = True,
+        with_syzygy_gpio = True,
         **kwargs)       :
         platform = butterstick.Platform(revision=revision, device=device ,toolchain=toolchain)
 
@@ -147,6 +149,11 @@ class BaseSoC(SoCCore):
                 pads         = platform.request_all("user_led"),
                 sys_clk_freq = sys_clk_freq)
 
+        # GPIOs ------------------------------------------------------------------------------------
+        if with_syzygy_gpio:
+            platform.add_extension(butterstick.raw_syzygy_io("SYZYGY0"))
+            self.submodules.gpio = GPIOTristate(platform.request("SYZYGY0"))
+
 # Build --------------------------------------------------------------------------------------------
 
 def main():
@@ -167,6 +174,7 @@ def main():
     sdopts = parser.add_mutually_exclusive_group()
     sdopts.add_argument("--with-spi-sdcard", action="store_true", help="Enable SPI-mode SDCard support.")
     sdopts.add_argument("--with-sdcard",     action="store_true", help="Enable SDCard support.")
+    parser.add_argument("--with-syzygy-gpio",action="store_true", help="Enable GPIOs through SYZYGY Breakout on Port-A.")
     builder_args(parser)
     soc_core_args(parser)
     trellis_args(parser)
@@ -185,6 +193,7 @@ def main():
         eth_ip           = args.eth_ip,
         eth_dynamic_ip   = args.eth_dynamic_ip,
         with_spi_flash   = args.with_spi_flash,
+        with_syzygy_gpio = args.with_syzygy_gpio,
         **soc_core_argdict(args))
     if args.with_spi_sdcard:
         soc.add_spi_sdcard()