Docs: Update for new build system

Update docs to use new build commands. Document new build options Remove
mentions of manifest generation. Remove mentions of hex file generation.

Signed-off-by: Anton Komlev <anton.komlev@arm.com>
Change-Id: I01c49c462403468c3e3650534893160cdfb6f5c5
diff --git a/docs/getting_started/tfm_build_instruction_iar.rst b/docs/getting_started/tfm_build_instruction_iar.rst
index facb744..8df576f 100644
--- a/docs/getting_started/tfm_build_instruction_iar.rst
+++ b/docs/getting_started/tfm_build_instruction_iar.rst
@@ -3,7 +3,7 @@
 ###################################################
 
 Follow the instructions in
-:doc:`software requirements <tfm_build_instruction>`, but replace the -DCOMPILER= setting with IARARM.
+:doc:`software requirements <tfm_build_instruction>`, but replace the -DCMAKE_TOOLCHAIN_FILE setting with toolchain_IARARM.cmake.
 
 
 Notes for building with IARARM
@@ -23,55 +23,45 @@
     For all configurations and build options some of the QCBOR tests fail due to the tests not handling
     double float NaN:s according to the Arm Runtime ABI. This should be sorted out in the future.
 
-    Some minor changes to the mbed-crypto pack is required to allow building TF-M with the
-    IAR tools. This will be sorted out once tf-m upgrades to >3.1.0
-
-    For mbed-crypto (CMakeLists.txt):
-
+Example: building TF-M for AN521 platform using IAR:
+====================================================
 .. code-block:: bash
 
-     if(CMAKE_COMPILER_IS_IAR)
-    -    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} --warn_about_c_style_casts --warnings_are_errors -Ohz")
-    +    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} --warn_about_c_style_casts")
-    +    set(CMAKE_C_FLAGS_RELEASE     "-Ohz")
-    +    set(CMAKE_C_FLAGS_DEBUG       "--debug -On")
-    +    set(CMAKE_C_FLAGS_CHECK       "--warnings_are_errors")
-     endif(CMAKE_COMPILER_IS_IAR)
+    cd <base folder>
+    cd trusted-firmware-m
+    cmake -S . -B cmake_build -DTFM_PLATFORM=mps2/an521 -DCMAKE_TOOLCHAIN_FILE=toolchain_IARARM.cmake
+    cmake --build cmake_build -- install
 
+Alternately using traditional cmake syntax
 
-Build steps:
-============
 .. code-block:: bash
 
     cd <base folder>
     cd trusted-firmware-m
     mkdir cmake_build
     cd cmake_build
-    cmake ../ -G"Unix Makefiles" -DTARGET_PLATFORM=AN521 -DCOMPILER=IARARM
-    cmake --build ./ -- install
+    cmake .. -DTFM_PLATFORM=mps2/an521 -DCMAKE_TOOLCHAIN_FILE=../toolchain_IARARM.cmake
+    make install
 
 Regression Tests for the AN521 target platform
 ==============================================
-*TF-M build regression tests on Linux*
 
 .. code-block:: bash
 
     cd <base folder>
     cd trusted-firmware-m
-    mkdir cmake_test
-    cd cmake_test
-    cmake -G"Unix Makefiles" -DPROJ_CONFIG=`readlink -f ../configs/ConfigRegression.cmake` -DTARGET_PLATFORM=AN521 -DCOMPILER=IARARM ../
-    cmake --build ./ -- install
+    cmake -S . -B cmake_build -DTFM_PLATFORM=mps2/an521 -DCMAKE_TOOLCHAIN_FILE=toolchain_IARARM.cmake -DTEST_S=ON -DTEST_NS=ON
+    cmake --build cmake_build -- install
 
-*TF-M build regression tests on Windows*
+Alternately using traditional cmake syntax
 
 .. code-block:: bash
 
     cd <base folder>
     cd trusted-firmware-m
-    mkdir cmake_test
-    cd cmake_test
-    cmake -G"Unix Makefiles" -DPROJ_CONFIG=`cygpath -am ../configs/ConfigRegression.cmake` -DTARGET_PLATFORM=AN521 -DCOMPILER=IARARM ../
-    cmake --build ./ -- install
+    mkdir cmake_build
+    cd cmake_build
+    cmake .. -DTFM_PLATFORM=mps2/an521 -DCMAKE_TOOLCHAIN_FILE=../toolchain_IARARM.cmake -DTEST_S=ON -DTEST_NS=ON
+    make install
 
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