cmake: extensions: add NAME parameter to DT register helpers

Allow register address and size access by name.

Example devicetree fragment:

  / {
          foo@deadbeef {
                  reg = <0xdeadbeef 0x1000>, <0xfeedface 0x2000>;
                  reg-names = "bar", "baz";
          };
  };

Example usage:

  dt_reg_addr(bar_addr PATH "/foo@deadbeef" NAME bar)
  dt_reg_size(bar_size PATH "/foo@deadbeef" NAME bar)

  dt_reg_addr(baz_addr PATH "/foo@deadbeef" NAME baz)
  dt_reg_size(baz_size PATH "/foo@deadbeef" NAME baz)

Results:

  - bar_addr is 0xdeadbeef
  - bar_size is 0x1000
  - baz_addr is 0xfeedface
  - baz_size is 0x2000

Signed-off-by: Martí Bolívar <[email protected]>

Author: mbolivar-nordic

cmake/extensions.cmake

@@ -2859,10 +2859,11 @@ function(dt_num_regs var)
 endfunction()
 
 # Usage:
-#   dt_reg_addr(<var> PATH <path> [INDEX <idx>])
+#   dt_reg_addr(<var> PATH <path> [INDEX <idx>] [NAME <name>])
 #
-# Get the base address of the register block at index <idx>.
-# If <idx> is omitted, then the value at index 0 will be returned.
+# Get the base address of the register block at index <idx>, or with
+# name <name>. If <idx> and <name> are both omitted, the value at
+# index 0 will be returned. Do not give both <idx> and <name>.
 #
 # The value will be returned in the <var> parameter.
 #
@@ -2875,14 +2876,15 @@ endfunction()
 # Results can be:
 # - The base address of the register block
 # - <var> will be undefined if node does not exists or does not have a register
-#   block at the requested index.
+#   block at the requested index or with the requested name
 #
 # <var>          : Return variable where the address value will be stored
 # PATH <path>    : Node path
-# INDEX <idx>    : Index number
+# INDEX <idx>    : Register block index number
+# NAME <name>    : Register block name
 function(dt_reg_addr var)
   set(req_single_args "PATH")
-  set(single_args "INDEX")
+  set(single_args "INDEX;NAME")
   cmake_parse_arguments(DT_REG "" "${req_single_args};${single_args}" "" ${ARGN})
 
   if(${ARGV0} IN_LIST req_single_args)
@@ -2897,8 +2899,16 @@ function(dt_reg_addr var)
     endif()
   endforeach()
 
-  if(NOT DEFINED DT_REG_INDEX)
+  if(DEFINED DT_REG_INDEX AND DEFINED DT_REG_NAME)
+    message(FATAL_ERROR "dt_reg_addr(${ARGV0} ...) given both INDEX and NAME")
+  elseif(NOT DEFINED DT_REG_INDEX AND NOT DEFINED DT_REG_NAME)
     set(DT_REG_INDEX 0)
+  elseif(DEFINED DT_REG_NAME)
+    dt_reg_index_private(DT_REG_INDEX "${DT_REG_PATH}" "${DT_REG_NAME}")
+    if(DT_REG_INDEX EQUAL "-1")
+      set(${var} PARENT_SCOPE)
+      return()
+    endif()
   endif()
 
   dt_path_internal(canonical "${DT_REG_PATH}")
@@ -2914,10 +2924,11 @@ function(dt_reg_addr var)
 endfunction()
 
 # Usage:
-#   dt_reg_size(<var> PATH <path> [INDEX <idx>])
+#   dt_reg_size(<var> PATH <path> [INDEX <idx>] [NAME <name>])
 #
-# Get the size of the register block at index <idx>.
-# If INDEX is omitted, then the value at index 0 will be returned.
+# Get the size of the register block at index <idx>, or with
+# name <name>. If <idx> and <name> are both omitted, the value at
+# index 0 will be returned. Do not give both <idx> and <name>.
 #
 # The value will be returned in the <value> parameter.
 #
@@ -2929,10 +2940,11 @@ endfunction()
 #
 # <var>          : Return variable where the size value will be stored
 # PATH <path>    : Node path
-# INDEX <idx>    : Index number
+# INDEX <idx>    : Register block index number
+# NAME <name>    : Register block name
 function(dt_reg_size var)
   set(req_single_args "PATH")
-  set(single_args "INDEX")
+  set(single_args "INDEX;NAME")
   cmake_parse_arguments(DT_REG "" "${req_single_args};${single_args}" "" ${ARGN})
 
   if(${ARGV0} IN_LIST req_single_args)
@@ -2947,8 +2959,16 @@ function(dt_reg_size var)
     endif()
   endforeach()
 
-  if(NOT DEFINED DT_REG_INDEX)
+  if(DEFINED DT_REG_INDEX AND DEFINED DT_REG_NAME)
+    message(FATAL_ERROR "dt_reg_size(${ARGV0} ...) given both INDEX and NAME")
+  elseif(NOT DEFINED DT_REG_INDEX AND NOT DEFINED DT_REG_NAME)
     set(DT_REG_INDEX 0)
+  elseif(DEFINED DT_REG_NAME)
+    dt_reg_index_private(DT_REG_INDEX "${DT_REG_PATH}" "${DT_REG_NAME}")
+    if(DT_REG_INDEX EQUAL "-1")
+      set(${var} PARENT_SCOPE)
+      return()
+    endif()
   endif()
 
   dt_path_internal(canonical "${DT_REG_PATH}")
@@ -2963,6 +2983,17 @@ function(dt_reg_size var)
   set(${var} ${${var}} PARENT_SCOPE)
 endfunction()
 
+# Internal helper for dt_reg_addr/dt_reg_size; not meant to be used directly
+function(dt_reg_index_private var path name)
+  dt_prop(reg_names PATH "${path}" PROPERTY "reg-names")
+  if(NOT DEFINED reg_names)
+    set(index "-1")
+  else()
+    list(FIND reg_names "${name}" index)
+  endif()
+  set(${var} "${index}" PARENT_SCOPE)
+endfunction()
+
 # Usage:
 #   dt_has_chosen(<var> PROPERTY <prop>)
 #