buildman: Allow make flags to be specified for each board

There are a few make options such as BUILD_TAG which can be provided when
building U-Boot. Provide a way for buildman to pass these flags to make
also.

The flags should be in a [make-flags] section and arranged by target name
(the 'target' column in boards.cfg. See the README for more details.

Signed-off-by: Simon Glass <sjg@chromium.org>

tools/buildman/README

@@ -629,6 +629,28 @@ It is common when refactoring code for the rodata to decrease as the text size
 increases, and vice versa.
 
 
+Providing 'make' flags
+======================
+
+U-Boot's build system supports a few flags (such as BUILD_TAG) which affect
+the build product. These flags can be specified in the buildman settings
+file. They can also be useful when building U-Boot against other open source
+software.
+
+[make-flags]
+at91-boards=ENABLE_AT91_TEST=1
+snapper9260=${at91-boards} BUILD_TAG=442
+snapper9g45=${at91-boards} BUILD_TAG=443
+
+This will use 'make ENABLE_AT91_TEST=1 BUILD_TAG=442' for snapper9260
+and 'make ENABLE_AT91_TEST=1 BUILD_TAG=442' for snapper9g45. A special
+variable ${target} is available to access the target name (snapper9260 and
+snapper9g20 in this case). Variables are resolved recursively.
+
+It is expected that any variables added are dealt with in U-Boot's
+config.mk file and documented in the README.
+
+
 Other options
 =============
 

tools/buildman/bsettings.py

@@ -36,9 +36,6 @@ def GetItems(section):
         return settings.items(section)
     except ConfigParser.NoSectionError as e:
         print e
-        print ("Warning: No tool chains - please add a [toolchain] section "
-                "to your buildman config file %s. See README for details" %
-                config_fname)
         return []
     except:
         raise

tools/buildman/builder.py

@@ -253,6 +253,7 @@ class BuilderThread(threading.Thread):
                     args.extend(['-j', str(self.builder.num_jobs)])
                 config_args = ['%s_config' % brd.target]
                 config_out = ''
+                args.extend(self.builder.toolchains.GetMakeArguments(brd))
 
                 # If we need to reconfigure, do that now
                 if do_config:

tools/buildman/buildman.py

@@ -32,6 +32,19 @@ import toolchain
 
 def RunTests():
     import test
+    import doctest
+
+    result = unittest.TestResult()
+    for module in ['toolchain']:
+        suite = doctest.DocTestSuite(module)
+        suite.run(result)
+
+    # TODO: Surely we can just 'print' result?
+    print result
+    for test, err in result.errors:
+        print err
+    for test, err in result.failures:
+        print err
 
     sys.argv = [sys.argv[0]]
     suite = unittest.TestLoader().loadTestsFromTestCase(test.TestBuild)

tools/buildman/toolchain.py

@@ -3,6 +3,7 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
+import re
 import glob
 import os
 
@@ -97,12 +98,18 @@ class Toolchains:
     def __init__(self):
         self.toolchains = {}
         self.paths = []
-        for name, value in bsettings.GetItems('toolchain'):
+        toolchains = bsettings.GetItems('toolchain')
+        if not toolchains:
+            print ("Warning: No tool chains - please add a [toolchain] section"
+                 " to your buildman config file %s. See README for details" %
+                 config_fname)
+
+        for name, value in toolchains:
             if '*' in value:
                 self.paths += glob.glob(value)
             else:
                 self.paths.append(value)
-
+        self._make_flags = dict(bsettings.GetItems('make-flags'))
 
     def Add(self, fname, test=True, verbose=False):
         """Add a toolchain to our list
@@ -167,3 +174,73 @@ class Toolchains:
         if not arch in self.toolchains:
             raise ValueError, ("No tool chain found for arch '%s'" % arch)
         return self.toolchains[arch]
+
+    def ResolveReferences(self, var_dict, args):
+        """Resolve variable references in a string
+
+        This converts ${blah} within the string to the value of blah.
+        This function works recursively.
+
+        Args:
+            var_dict: Dictionary containing variables and their values
+            args: String containing make arguments
+        Returns:
+            Resolved string
+
+        >>> bsettings.Setup()
+        >>> tcs = Toolchains()
+        >>> tcs.Add('fred', False)
+        >>> var_dict = {'oblique' : 'OBLIQUE', 'first' : 'fi${second}rst', \
+                        'second' : '2nd'}
+        >>> tcs.ResolveReferences(var_dict, 'this=${oblique}_set')
+        'this=OBLIQUE_set'
+        >>> tcs.ResolveReferences(var_dict, 'this=${oblique}_set${first}nd')
+        'this=OBLIQUE_setfi2ndrstnd'
+        """
+        re_var = re.compile('(\$\{[a-z0-9A-Z]{1,}\})')
+
+        while True:
+            m = re_var.search(args)
+            if not m:
+                break
+            lookup = m.group(0)[2:-1]
+            value = var_dict.get(lookup, '')
+            args = args[:m.start(0)] + value + args[m.end(0):]
+        return args
+
+    def GetMakeArguments(self, board):
+        """Returns 'make' arguments for a given board
+
+        The flags are in a section called 'make-flags'. Flags are named
+        after the target they represent, for example snapper9260=TESTING=1
+        will pass TESTING=1 to make when building the snapper9260 board.
+
+        References to other boards can be added in the string also. For
+        example:
+
+        [make-flags]
+        at91-boards=ENABLE_AT91_TEST=1
+        snapper9260=${at91-boards} BUILD_TAG=442
+        snapper9g45=${at91-boards} BUILD_TAG=443
+
+        This will return 'ENABLE_AT91_TEST=1 BUILD_TAG=442' for snapper9260
+        and 'ENABLE_AT91_TEST=1 BUILD_TAG=443' for snapper9g45.
+
+        A special 'target' variable is set to the board target.
+
+        Args:
+            board: Board object for the board to check.
+        Returns:
+            'make' flags for that board, or '' if none
+        """
+        self._make_flags['target'] = board.target
+        arg_str = self.ResolveReferences(self._make_flags,
+                           self._make_flags.get(board.target, ''))
+        args = arg_str.split(' ')
+        i = 0
+        while i < len(args):
+            if not args[i]:
+                del args[i]
+            else:
+                i += 1
+        return args