diff --git a/CMakeLists.txt b/CMakeLists.txt
index 80fa88636ca55..b479ad2229667 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -792,10 +792,9 @@ else()
       OUTPUT nuttx.rel
       COMMAND
         ${CMAKE_C_COMPILER} ARGS -r $<$<BOOL:${CONFIG_SIM_M32}>:-m32>
-        $<$<BOOL:${CONFIG_HOST_LINUX}>:-Wl,-z,noexecstack>
-        $<TARGET_OBJECTS:sim_head> $<$<NOT:$<BOOL:${APPLE}>>:-Wl,--start-group>
-        ${nuttx_libs_paths} $<$<NOT:$<BOOL:${APPLE}>>:-Wl,--end-group> -o
-        nuttx.rel
+        $<$<BOOL:${LINUX}>:-Wl,-z,noexecstack> $<TARGET_OBJECTS:sim_head>
+        $<$<NOT:$<BOOL:${APPLE}>>:-Wl,--start-group> ${nuttx_libs_paths}
+        $<$<NOT:$<BOOL:${APPLE}>>:-Wl,--end-group> -o nuttx.rel
       COMMAND ${CMAKE_OBJCOPY} --redefine-syms=nuttx-names.dat nuttx.rel
       DEPENDS ${nuttx_libs} sim_head sim_redefine_symbols
       COMMAND_EXPAND_LISTS)
diff --git a/arch/sim/src/cmake/Toolchain.cmake b/arch/sim/src/cmake/Toolchain.cmake
index e326dca663e54..dcec62d66bd43 100644
--- a/arch/sim/src/cmake/Toolchain.cmake
+++ b/arch/sim/src/cmake/Toolchain.cmake
@@ -20,8 +20,24 @@
 #
 # ##############################################################################
 
+if(CMAKE_HOST_SYSTEM_NAME STREQUAL "Linux")
+  set(SIM_HOST_LINUX true)
+elseif(CMAKE_HOST_SYSTEM_NAME STREQUAL "Darwin")
+  set(SIM_HOST_MACOS true)
+endif()
+
+if(CMAKE_HOST_SYSTEM_PROCESSOR MATCHES "^(x86_64|amd64|AMD64)$")
+  set(SIM_HOST_X86_64 true)
+elseif(CMAKE_HOST_SYSTEM_PROCESSOR MATCHES "^(i[3-6]86|x86)$")
+  set(SIM_HOST_X86_32 true)
+elseif(CMAKE_HOST_SYSTEM_PROCESSOR MATCHES "^(aarch64|arm64)$")
+  set(SIM_HOST_ARM64 true)
+elseif(CMAKE_HOST_SYSTEM_PROCESSOR MATCHES "^(arm|armv[0-9].*)$")
+  set(SIM_HOST_ARM true)
+endif()
+
 if(APPLE AND CONFIG_SIM_TOOLCHAIN_GCC)
-  if(CONFIG_HOST_ARM64)
+  if(SIM_HOST_ARM64)
     find_program(CMAKE_C_ELF_COMPILER aarch64-elf-gcc)
     find_program(CMAKE_CXX_ELF_COMPILER aarch64-elf-g++)
   else()
@@ -41,14 +57,14 @@ if(WIN32)
   return()
 endif()
 
-if(CONFIG_HOST_LINUX)
+if(SIM_HOST_LINUX)
   set(CMAKE_LD ld)
   set(CMAKE_PREPROCESSOR cc -E -P -x c)
   set(CMAKE_STRIP strip --strip-unneeded)
 endif()
 
 # LLVM style architecture flags
-if(CONFIG_HOST_X86_64)
+if(SIM_HOST_X86_64)
   if(CONFIG_SIM_M32)
     set(LLVM_ARCHTYPE "x86")
     set(LLVM_CPUTYPE "i686")
@@ -56,18 +72,18 @@ if(CONFIG_HOST_X86_64)
     set(LLVM_ARCHTYPE "x86_64")
     set(LLVM_CPUTYPE "skylake")
   endif()
-elseif(CONFIG_HOST_X86_32)
+elseif(SIM_HOST_X86_32)
   set(LLVM_ARCHTYPE "x86")
   set(LLVM_CPUTYPE "i686")
-elseif(CONFIG_HOST_ARM64)
+elseif(SIM_HOST_ARM64)
   set(LLVM_ARCHTYPE "aarch64")
   set(LLVM_CPUTYPE "cortex-a53")
-elseif(CONFIG_HOST_ARM)
+elseif(SIM_HOST_ARM)
   set(LLVM_ARCHTYPE "arm")
   set(LLVM_CPUTYPE "cortex-a9")
 endif()
 
-if(CONFIG_HOST_LINUX OR CONFIG_HOST_MACOS)
+if(SIM_HOST_LINUX OR SIM_HOST_MACOS)
   set(LLVM_ABITYPE "sysv")
 elseif(WIN32)
   set(LLVM_ABITYPE "msvc")
@@ -230,7 +246,14 @@ endif()
 if(CONFIG_SIM_M32)
   add_compile_options(-m32)
   add_link_options(-m32)
-elseif(NOT APPLE)
+elseif(NOT APPLE AND NOT SIM_HOST_ARM64)
+  # To compile 64-bit Sim, adding no-pie is necessary to prevent linking errors
+  # but this may cause other issues on Ubuntu 20.
+  #
+  # NOTE: HOST_ARM64 is also excluded -- Ubuntu/Debian arm64 toolchains ship
+  # only libgcc_s.so.1 (no libgcc_s.a), and -no-pie forces gcc to look for the
+  # static archive; skipping it lets gcc use the default PIE link path which
+  # works correctly on aarch64 hosts.
   add_compile_options(-no-pie)
   add_link_options(-Wl,-no-pie)
 endif()
@@ -254,6 +277,6 @@ else()
   add_link_options(-Wl,-Ttext-segment=0x40000000)
 endif()
 
-if(CONFIG_HOST_LINUX)
+if(SIM_HOST_LINUX)
   add_link_options(-Wl,-z,noexecstack)
 endif()
diff --git a/boards/sim/sim/sim/scripts/Make.defs b/boards/sim/sim/sim/scripts/Make.defs
index 009c76b162272..2cc3d159d27c5 100644
--- a/boards/sim/sim/sim/scripts/Make.defs
+++ b/boards/sim/sim/sim/scripts/Make.defs
@@ -151,7 +151,7 @@ ifeq ($(CONFIG_SIM_M32),y)
 else
   ARCHCFLAGS += -fno-pic
   ARCHCXXFLAGS += -fno-pic
-  ifneq ($(CONFIG_HOST_MACOS),y)
+  ifeq ($(CONFIG_HOST_X86_64),y)
     ARCHCFLAGS += -mcmodel=medium
     ARCHCXXFLAGS += -mcmodel=medium
   endif
@@ -167,7 +167,7 @@ ifeq ($(CONFIG_HOST_X86_64),y)
     LLVM_ARCHTYPE := x86_64
     LLVM_CPUTYPE := skylake
   endif
-else ifeq ($(CONFIG_HOST_X86_32),y)
+else ifeq ($(CONFIG_HOST_X86),y)
   LLVM_ARCHTYPE := x86
   LLVM_CPUTYPE := i686
 else ifeq ($(CONFIG_HOST_ARM64),y)
diff --git a/cmake/nuttx_sethost.cmake b/cmake/nuttx_sethost.cmake
index f26399b587b47..603be508a5ad6 100644
--- a/cmake/nuttx_sethost.cmake
+++ b/cmake/nuttx_sethost.cmake
@@ -110,7 +110,7 @@ function(nuttx_sethost)
     elseif(ARCHITECTURE STREQUAL "arm")
       message("  Select HOST_ARM=y")
       list(APPEND NUTTX_SYSTEM_SETHOST "HOST_ARM=y")
-    elseif(ARCHITECTURE STREQUAL "arm64")
+    elseif(ARCHITECTURE MATCHES "^(arm64|aarch64)$")
       message("  Select HOST_ARM64=y")
       list(APPEND NUTTX_SYSTEM_SETHOST "HOST_ARM64=y")
     endif()
diff --git a/tools/Rust.defs b/tools/Rust.defs
index 42ccffb37c142..50225761e63a0 100644
--- a/tools/Rust.defs
+++ b/tools/Rust.defs
@@ -41,10 +41,14 @@ ifeq ($(CONFIG_ARCH_SIM),y)
       RUSTFLAGS += --target i686-unknown-linux-gnu
     else
       # For other archs, such as aarch64, arm etc
-        RUSTFLAGS += --target $(LLVM_ARCHTYPE)-unknown-linux-gnu
+      RUSTFLAGS += --target $(LLVM_ARCHTYPE)-unknown-linux-gnu
     endif
   else ifeq ($(CONFIG_HOST_MACOS),y)
-    RUSTFLAGS += --target $(LLVM_ARCHTYPE)-apple-darwin
+    ifeq ($(LLVM_ARCHTYPE),aarch64)
+      RUSTFLAGS += --target $(TOPDIR)/tools/aarch64-unknown-nuttx-macho.json
+    else
+      $(error Unsupported Rust SIM target on macOS: LLVM_ARCHTYPE=$(LLVM_ARCHTYPE))
+    endif
   endif
 else ifeq ($(CONFIG_ARCH_RISCV),y)
   # Target triple is riscv[32|64][isa]-unknown-none-elf
diff --git a/tools/aarch64-unknown-nuttx-macho.json b/tools/aarch64-unknown-nuttx-macho.json
new file mode 100644
index 0000000000000..5410ffd9f2104
--- /dev/null
+++ b/tools/aarch64-unknown-nuttx-macho.json
@@ -0,0 +1,35 @@
+{
+  "arch": "aarch64",
+  "archive-format": "darwin",
+  "binary-format": "mach-o",
+  "crt-objects-fallback": "false",
+  "data-layout": "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32",
+  "debuginfo-kind": "dwarf",
+  "default-uwtable": true,
+  "disable-redzone": true,
+  "emit-debug-gdb-scripts": false,
+  "features": "+v8a,+strict-align,+neon",
+  "frame-pointer": "non-leaf",
+  "function-sections": false,
+  "linker-flavor": "gnu-lld",
+  "lld-flavor": "darwin",
+  "llvm-target": "arm64-apple-macosx",
+  "max-atomic-width": 128,
+  "metadata": {
+    "description": "aarch64 Mach-O target for NuttX sim on macOS",
+    "host_tools": false,
+    "std": true,
+    "tier": 3
+  },
+  "os": "nuttx",
+  "panic-strategy": "abort",
+  "split-debuginfo": "off",
+  "stack-probes": {
+    "kind": "inline"
+  },
+  "target-family": [
+    "unix"
+  ],
+  "target-pointer-width": 64,
+  "vendor": "unknown"
+}