diff --git a/docs/Dialects/ICE40/RationaleICE40.md b/docs/Dialects/ICE40/RationaleICE40.md
new file mode 100644
index 000000000000..ee8aaf8920fb
--- /dev/null
+++ b/docs/Dialects/ICE40/RationaleICE40.md
@@ -0,0 +1,17 @@
+# `ice40` Dialect Rationale
+
+This document describes various design points of the ice40 dialect, a 
+dialect that matches the technology library used in the Lattice ICE40 family
+of FPGAs.
+
+## Introduction to the `ice40` Dialect
+
+The `ice40` dialect provides a collection of operations that match the
+documented operations for the ICE40 family of FPGAs.  The dialect hues closely
+to the documentation.
+
+The intent of the dialect is as a target of synthesis.
+
+## Type System for `ice40` Dialect
+
+The dialect uses signless 1-bit integers for all values.
diff --git a/include/circt/Dialect/CMakeLists.txt b/include/circt/Dialect/CMakeLists.txt
index e5b55dcb068e..62155eaf5b97 100644
--- a/include/circt/Dialect/CMakeLists.txt
+++ b/include/circt/Dialect/CMakeLists.txt
@@ -19,6 +19,7 @@ add_subdirectory(FSM)
 add_subdirectory(Handshake)
 add_subdirectory(HW)
 add_subdirectory(HWArith)
+add_subdirectory(ICE40)
 add_subdirectory(Interop)
 add_subdirectory(LLHD)
 add_subdirectory(LoopSchedule)
diff --git a/include/circt/Dialect/ICE40/CMakeLists.txt b/include/circt/Dialect/ICE40/CMakeLists.txt
new file mode 100644
index 000000000000..8b5453d3a86f
--- /dev/null
+++ b/include/circt/Dialect/ICE40/CMakeLists.txt
@@ -0,0 +1,3 @@
+add_circt_dialect(ICE40 ice40)
+
+set(LLVM_TARGET_DEFINITIONS ICE40.td)
diff --git a/include/circt/Dialect/ICE40/ICE40.td b/include/circt/Dialect/ICE40/ICE40.td
new file mode 100644
index 000000000000..4c8a8b804375
--- /dev/null
+++ b/include/circt/Dialect/ICE40/ICE40.td
@@ -0,0 +1,20 @@
+//===- ICE40.td - ICE40 FPGA dialect definition ------------*- tablegen -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This is the top level file for the ICE40 dialect.  This dialect targets the
+// Lattice ICE40 FPGA technology library.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CIRCT_DIALECT_ICE40_ICE40_TD
+#define CIRCT_DIALECT_ICE40_ICE40_TD
+
+include "circt/Dialect/ICE40/ICE40Dialect.td"
+include "circt/Dialect/ICE40/ICE40Ops.td"
+
+#endif // CIRCT_DIALECT_ICE40_ICE40_TD
diff --git a/include/circt/Dialect/ICE40/ICE40Dialect.h b/include/circt/Dialect/ICE40/ICE40Dialect.h
new file mode 100644
index 000000000000..170184b57c9d
--- /dev/null
+++ b/include/circt/Dialect/ICE40/ICE40Dialect.h
@@ -0,0 +1,23 @@
+//===- ICE40Dialect.h - ICE40 dialect declaration ---------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines an ICE40 MLIR dialect.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CIRCT_DIALECT_ICE40_ICE40DIALECT_H
+#define CIRCT_DIALECT_ICE40_ICE40DIALECT_H
+
+#include "circt/Support/LLVM.h"
+#include "mlir/IR/BuiltinAttributes.h"
+#include "mlir/IR/Dialect.h"
+
+// Pull in the dialect definition.
+#include "circt/Dialect/ICE40/ICE40Dialect.h.inc"
+
+#endif // CIRCT_DIALECT_ICE40_ICE40DIALECT_H
diff --git a/include/circt/Dialect/ICE40/ICE40Dialect.td b/include/circt/Dialect/ICE40/ICE40Dialect.td
new file mode 100644
index 000000000000..a21f9e510eb8
--- /dev/null
+++ b/include/circt/Dialect/ICE40/ICE40Dialect.td
@@ -0,0 +1,33 @@
+//===- ICE40Dialect.td - ICE40 dialect definition ----------*- tablegen -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This contains the ICE40Dialect definition to be included in other files.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CIRCT_DIALECT_ICE40_ICE40DIALECT
+#define CIRCT_DIALECT_ICE40_ICE40DIALECT
+
+include "mlir/IR/OpBase.td"
+
+def ICE40Dialect : Dialect {
+  let name = "ice40";
+  let cppNamespace = "::circt::ice40";
+
+  let summary = "Types and operations for the ICE40 technology library dialect";
+  let description = [{
+    This dialect defines the `ice40` dialect, which is a dialect of the technology
+    library for the Lattice ICE40 family of products.
+  }];
+}
+
+// Base class for the operation in this dialect.
+class ICE40Op<string mnemonic, list<Trait> traits = []> :
+    Op<ICE40Dialect, mnemonic, traits>;
+
+#endif // CIRCT_DIALECT_ICE40_ICE40DIALECT
diff --git a/include/circt/Dialect/ICE40/ICE40Ops.h b/include/circt/Dialect/ICE40/ICE40Ops.h
new file mode 100644
index 000000000000..4e3475583669
--- /dev/null
+++ b/include/circt/Dialect/ICE40/ICE40Ops.h
@@ -0,0 +1,23 @@
+//===- ICE40Ops.h - Declare ICE40 dialect operations ------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares the operation classes for the ICE40 dialect.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CIRCT_DIALECT_ICE40_ICE40OPS_H
+#define CIRCT_DIALECT_ICE40_ICE40OPS_H
+
+#include "circt/Dialect/ICE40/ICE40Dialect.h"
+#include "mlir/Bytecode/BytecodeOpInterface.h"
+#include "mlir/IR/OpImplementation.h"
+
+#define GET_OP_CLASSES
+#include "circt/Dialect/ICE40/ICE40.h.inc"
+
+#endif // CIRCT_DIALECT_ICE40_ICE40OPS_H
diff --git a/include/circt/Dialect/ICE40/ICE40Ops.td b/include/circt/Dialect/ICE40/ICE40Ops.td
new file mode 100644
index 000000000000..9fdc6bfcddaf
--- /dev/null
+++ b/include/circt/Dialect/ICE40/ICE40Ops.td
@@ -0,0 +1,74 @@
+//===- ICE40Ops.td - ICE40 ops ============-----------------*- tablegen -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This defines the ICE40 ops, matching the technology library.  Documentation
+// is here: https://www.latticesemi.com/-/media/LatticeSemi/Documents/TechnicalBriefs/FPGA-TN-02026-3-2-iCE40-Technology-Library.ashx?document_id=52206
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CIRCT_DIALECT_ICE40_ICE40OPS_TD
+#define CIRCT_DIALECT_ICE40_ICE40OPS_TD
+
+include "circt/Dialect/ICE40/ICE40Dialect.td"
+
+def I1Property : IntProperty<"bool">;
+
+def SBLut4Op : ICE40Op<"sb_lut4", []> {
+  let summary = "A basic lut";
+  let description = [{
+    The basic look up table.  f(i0, i1, i2, i3) = lut_init[concat(i3,i2,i1,i0)].
+    }];
+
+  let arguments = (ins I1:$i0, I1:$i1, I1:$i2, I1:$i3, ArrayProperty<I1Property>:$lut_init);
+  let results = (outs I1:$result);
+
+  let hasVerifier = 1;
+
+  let assemblyFormat = [{
+    $i0 `,` $i1 `,` $i2 `,` $i3 `,` $lut_init attr-dict
+  }];
+}
+
+def SBCarryOp : ICE40Op<"sb_carry", []> {
+  let summary = "Dedicated carry Lookahead logic";
+  let description = [{
+    The basic carry lookahead logic.  f(i0, i1, ci) = 1 iff popcount(concat(i0,i1,ci)) >= 2.
+    There are constraints on the use, as i0 and i1 have to be the i0 and i1 input of a single lut.
+    This op doesn't check this.  There is a combined op that handles that.
+    }];
+
+  let arguments = (ins I1:$i0, I1:$i1, I1:$ci);
+  let results = (outs I1:$result);
+
+  let hasVerifier = 1;
+
+  let assemblyFormat = [{
+    $i0 `,` $i1 `,` $ci attr-dict
+  }];
+}
+
+def SBLut4CarryOp : ICE40Op<"sb_lut4_carry", []> {
+  let summary = "LUT which also utilizes the carry logic";
+  let description = [{
+      carry_out(i0, i1, ci) = 1 iff popcount(concat(i0,i1,ci)) >= 2.
+      result(i0, i1, i2, i3) = lut_init[concat(i3,i2,i1,i0)].
+    There are constraints on the use, as i0 and i1 have to be the i0 and i1 input of a single lut.
+    This op doesn't check this.  There is a combined op that handles that.
+    }];
+
+  let arguments = (ins I1:$i0, I1:$i1, I1:$i2, I1:$i3, I1:$ci, ArrayProperty<I1Property>:$lut_init);
+  let results = (outs I1:$result, I1:$carry_out);
+
+  let hasVerifier = 1;
+
+  let assemblyFormat = [{
+    $i0 `,` $i1 `,` $i2 `,` $i3 `,` $ci `,` $lut_init attr-dict
+  }];
+}
+
+#endif // CIRCT_DIALECT_ICE40_ICE40OPS_TD
diff --git a/include/circt/InitAllDialects.h b/include/circt/InitAllDialects.h
index 8e53c5fe211a..1825e1ac123e 100644
--- a/include/circt/InitAllDialects.h
+++ b/include/circt/InitAllDialects.h
@@ -28,6 +28,7 @@
 #include "circt/Dialect/HW/HWDialect.h"
 #include "circt/Dialect/HWArith/HWArithDialect.h"
 #include "circt/Dialect/Handshake/HandshakeDialect.h"
+#include "circt/Dialect/ICE40/ICE40Dialect.h"
 #include "circt/Dialect/Interop/InteropDialect.h"
 #include "circt/Dialect/Kanagawa/KanagawaDialect.h"
 #include "circt/Dialect/LLHD/IR/LLHDDialect.h"
@@ -70,6 +71,7 @@ inline void registerAllDialects(mlir::DialectRegistry &registry) {
     handshake::HandshakeDialect,
     hw::HWDialect,
     hwarith::HWArithDialect,
+    ice40::ICE40Dialect,
     interop::InteropDialect,
     kanagawa::KanagawaDialect,
     llhd::LLHDDialect,
diff --git a/lib/Dialect/CMakeLists.txt b/lib/Dialect/CMakeLists.txt
index a7bf7be67e1f..d086f601dd86 100644
--- a/lib/Dialect/CMakeLists.txt
+++ b/lib/Dialect/CMakeLists.txt
@@ -23,6 +23,7 @@ add_subdirectory(Handshake)
 add_subdirectory(HW)
 add_subdirectory(HWArith)
 add_subdirectory(Kanagawa)
+add_subdirectory(ICE40)
 add_subdirectory(Interop)
 add_subdirectory(LLHD)
 add_subdirectory(LoopSchedule)
diff --git a/lib/Dialect/ICE40/CMakeLists.txt b/lib/Dialect/ICE40/CMakeLists.txt
new file mode 100644
index 000000000000..b9f12eeacf57
--- /dev/null
+++ b/lib/Dialect/ICE40/CMakeLists.txt
@@ -0,0 +1,19 @@
+add_circt_dialect_library(CIRCTICE40
+  ICE40Ops.cpp
+  ICE40Dialect.cpp
+
+  ADDITIONAL_HEADER_DIRS
+  ${CIRCT_MAIN_INCLUDE_DIR}/circt/Dialect/ICE40
+
+  DEPENDS
+  MLIRICE40IncGen
+  
+  LINK_COMPONENTS
+  Support
+
+  LINK_LIBS PUBLIC
+  MLIRIR
+  MLIRInferTypeOpInterface
+   )
+
+add_dependencies(circt-headers MLIRICE40IncGen)
diff --git a/lib/Dialect/ICE40/ICE40Dialect.cpp b/lib/Dialect/ICE40/ICE40Dialect.cpp
new file mode 100644
index 000000000000..152a91261844
--- /dev/null
+++ b/lib/Dialect/ICE40/ICE40Dialect.cpp
@@ -0,0 +1,33 @@
+//===- ICE40Dialect.cpp - Implement the ICE40 dialect ---------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the ICE40 dialect.
+//
+//===----------------------------------------------------------------------===//
+
+#include "circt/Dialect/ICE40/ICE40Dialect.h"
+#include "circt/Dialect/ICE40/ICE40Ops.h"
+#include "mlir/IR/BuiltinTypes.h"
+#include "mlir/IR/DialectImplementation.h"
+
+using namespace circt;
+using namespace ice40;
+
+//===----------------------------------------------------------------------===//
+// Dialect specification.
+//===----------------------------------------------------------------------===//
+
+void ICE40Dialect::initialize() {
+  // Register operations.
+  addOperations<
+#define GET_OP_LIST
+#include "circt/Dialect/ICE40/ICE40.cpp.inc"
+      >();
+}
+
+#include "circt/Dialect/ICE40/ICE40Dialect.cpp.inc"
diff --git a/lib/Dialect/ICE40/ICE40Ops.cpp b/lib/Dialect/ICE40/ICE40Ops.cpp
new file mode 100644
index 000000000000..227e37e89d1d
--- /dev/null
+++ b/lib/Dialect/ICE40/ICE40Ops.cpp
@@ -0,0 +1,44 @@
+//===- ICE40Ops.cpp - Implement the ICE40 operations ----------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements ICE40 ops.
+//
+//===----------------------------------------------------------------------===//
+
+#include "circt/Dialect/ICE40/ICE40Ops.h"
+#include "mlir/IR/DialectImplementation.h"
+#include "mlir/IR/ImplicitLocOpBuilder.h"
+
+using namespace circt;
+using namespace ice40;
+
+//===----------------------------------------------------------------------===//
+// SBLut4Op
+//===----------------------------------------------------------------------===//
+
+LogicalResult SBLut4Op::verify() { return success(); }
+
+//===----------------------------------------------------------------------===//
+// SBCarryOp
+//===----------------------------------------------------------------------===//
+
+LogicalResult SBCarryOp::verify() { return success(); }
+
+//===----------------------------------------------------------------------===//
+// SBLut4CarryOp
+//===----------------------------------------------------------------------===//
+
+LogicalResult SBLut4CarryOp::verify() { return success(); }
+
+//===----------------------------------------------------------------------===//
+// TableGen generated logic.
+//===----------------------------------------------------------------------===//
+
+// Provide the autogenerated implementation guts for the Op classes.
+#define GET_OP_CLASSES
+#include "circt/Dialect/ICE40/ICE40.cpp.inc"
diff --git a/test/Dialect/ICE40/basic.mlir b/test/Dialect/ICE40/basic.mlir
new file mode 100644
index 000000000000..28e5a31b5273
--- /dev/null
+++ b/test/Dialect/ICE40/basic.mlir
@@ -0,0 +1,11 @@
+// RUN: circt-opt %s | FileCheck %s
+
+func.func @basic(%i : i1) {
+    // CHECK: ice40.sb_lut4
+    %a = ice40.sb_lut4 %i, %i, %i, %i, [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1]
+    // CHECK: ice40.sb_carry
+    %b = ice40.sb_carry %i, %i, %a
+    // CHECK: ice40.sb_lut4_carry
+    %c, %d = ice40.sb_lut4_carry %i, %i, %a, %a, %b, [1,0,1,1,0,1,1,1,0,1,1,1,1,0,1,1]
+    func.return
+}