cts: Fix back-to-back build

Currently eCTS suites share the same directory (e.g. build/stm32l476g
-eval) to put build artifacts even though some files (e.g. board.c)
compile differently suite to suite. So, if cts-i2c-stm32l476g-eval is
built, followed by cts-gpio-stm32l476g-eval, build fails or produces
incorrect binary.

This patch makes eCTS create different directories for each suite.
As a bonus, we can now builds eCTS suites in parallel.

BUG=chromium:654549
BRANCH=none
TEST=make buildall -j (with uncommitted change)

Change-Id: I4abedc917787be5f79b97e0e50d0d08e01bd5f9d
Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/398281

4 files changed, 16 insertions, 15 deletions

diff --git a/Makefile b/Makefile
index 3b5c4e70d4..912c6ab64d 100644
--- a/Makefile
+++ b/Makefile
@@ -23,7 +23,12 @@ endif
 PROJECT?=ec
 
 # Output directory for build objects
+ifdef CTS_MODULE
+# CTS builds need different directories per board per suite.
+out?=build/$(BOARD)/cts_$(CTS_MODULE)
+else
 out?=build/$(BOARD)
+endif
 
 # File containing configuration information
 config=$(out)/.config
diff --git a/Makefile.rules b/Makefile.rules
index 4f11ba1e55..4d028149e7 100644
--- a/Makefile.rules
+++ b/Makefile.rules
@@ -185,17 +185,10 @@ cts_boards := stm32l476g-eval nucleo-f072rb
 # Create CTS rule automatically for given suite and board
 # $1: suite name
 # $2: board name
-# $3: suite name used in the previous loop
 define make-cts =
-ifneq ($$(filter $(1),$$(cts_suites)),)
-ifneq ($$(filter $(3),$$(cts_suites)),)
-# Serialize builds
-cts-$(1)-$(2): cts-$(3)-$(2)
-endif
 build_cts: cts-$(1)-$(2)
 cts-$(1)-$(2):
 	$$(MAKE) CTS_MODULE=$(1) BOARD=$(2)
-endif
 # Do not remove this blank line
 
 endef
@@ -205,8 +198,8 @@ endef
 # If we don't serialize targets, parallel make fails because all suites
 # try to produce ec.bin in the same directory (e.g. build/stm32l476g-eval).
 $(foreach b, $(cts_boards), \
-	$(foreach s, $(cts_suites) none, \
-		$(eval $(call make-cts,$(s),$(b),$(prev)) prev:=$(s)) \
+	$(foreach s, $(cts_suites), \
+		$(eval $(call make-cts,$(s),$(b))) \
 	) \
 )
 
diff --git a/cts/common/board.py b/cts/common/board.py
index a36ca1a3a7..42479e6de3 100644
--- a/cts/common/board.py
+++ b/cts/common/board.py
@@ -109,8 +109,7 @@ class Board(object):
             '--directory=' + ec_dir,
             'BOARD=' + self.board,
             'CTS_MODULE=' + module,
-            '-j',
-            '-B']
+            '-j']
 
     if debug:
       cmds.append('CTS_DEBUG=TRUE')
@@ -118,9 +117,8 @@ class Board(object):
     print ' '.join(cmds)
     return sp.call(cmds)
 
-  def flash(self):
+  def flash(self, image_path):
     """Flashes board with most recent build ec.bin"""
-    image_path = os.path.join('build', self.board, 'ec.bin')
     cmd = ['reset_config connect_assert_srst',
            'init',
            'reset init',
diff --git a/cts/cts.py b/cts/cts.py
index 6a02b065bc..2d2e824cbc 100755
--- a/cts/cts.py
+++ b/cts/cts.py
@@ -101,10 +101,15 @@ class Cts(object):
 
   def flash_boards(self):
     """Flashes th and dut boards with their most recently build ec.bin"""
+    cts_module = 'cts_' + self.module
+    image_path = os.path.join('build', self.th.board, cts_module, 'ec.bin')
     self.identify_boards()
-    if self.th.flash():
+    print 'Flashing TH with', image_path
+    if self.th.flash(image_path):
       raise RuntimeError('Flashing TH failed')
-    if self.dut.flash():
+    image_path = os.path.join('build', self.dut.board, cts_module, 'ec.bin')
+    print 'Flashing DUT with', image_path
+    if self.dut.flash(image_path):
       raise RuntimeError('Flashing DUT failed')
 
   def setup(self):