cts: Added sync() function

sync() involves 2 gpios on each board, each labeled
GPIO_HANDSHAKE_OUTPUT and GPIO_HANDSHAKE_INPUT on
their respective boards. They both start low,
then the th wiggles his line up and down, waiting
for the dut to mimic it.

BRANCH=None
BUG=None
TEST=manual
- Connect handshake lines to appropriate
  pins on each board (pins found
  in board's gpio.inc)
- Build tests
- Flash boards
- run 'cat /dev/ttyACM0' in one terminal
- run 'cat /dev/ttyACM1' in another
- They should each have printed
  'successful sync'

Change-Id: I61233bca9605ba89c3628c2a65ca9013c56365ea
Reviewed-on: https://chromium-review.googlesource.com/359355
Commit-Ready: Chris Chen <twothreecc@google.com>
Tested-by: Chris Chen <twothreecc@google.com>
Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>

8 files changed, 136 insertions, 0 deletions

diff --git a/cts/build.mk b/cts/build.mk
index af01cfb102..6766a9fb4c 100644
--- a/cts/build.mk
+++ b/cts/build.mk
@@ -5,6 +5,8 @@
 
 ifeq ($(BOARD),stm32l476g-eval)
 	cts-y+=$(CTS_MODULE)/th.o
+	cts-y+=common/th_common.o
 else
 	cts-y+=$(CTS_MODULE)/dut.o
+	cts-y+=common/dut_common.o
 endif
\ No newline at end of file
diff --git a/cts/common/cts_common.h b/cts/common/cts_common.h
new file mode 100644
index 0000000000..eed93dccea
--- /dev/null
+++ b/cts/common/cts_common.h
@@ -0,0 +1,26 @@
+/* Copyright 2016 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef __CTS_COMMON_H
+#define __CTS_COMMON_H
+
+#include "console.h"
+
+/* Console output macros */
+#define CPUTS(outstr) cputs(CC_SYSTEM, outstr)
+#define CPRINTF(format, args...) cprintf(CC_SYSTEM, format, ## args)
+#define CPRINTS(format, args...) cprints(CC_SYSTEM, format, ## args)
+
+/* In a single test, only one board can return unknown, the other must
+ * return a useful result (i.e. success, failure, etc)
+ */
+enum cts_error_code {
+	SUCCESS,
+	FAILURE,
+	BAD_SYNC,
+	UNKNOWN
+};
+
+#endif
diff --git a/cts/common/dut_common.c b/cts/common/dut_common.c
new file mode 100644
index 0000000000..f8c18fd81c
--- /dev/null
+++ b/cts/common/dut_common.c
@@ -0,0 +1,31 @@
+/* Copyright 2016 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "gpio.h"
+#include "timer.h"
+#include "watchdog.h"
+#include "cts_common.h"
+
+/* Returns unknown because TH could potentially still get stuck
+ * even if the DUT completes the sync
+ */
+enum cts_error_code sync(void)
+{
+	int input_level;
+
+	gpio_set_level(GPIO_HANDSHAKE_OUTPUT, 0);
+	do {
+		watchdog_reload();
+		input_level = gpio_get_level(GPIO_HANDSHAKE_INPUT);
+	} while (!input_level);
+	gpio_set_level(GPIO_HANDSHAKE_OUTPUT, 1);
+	do {
+		watchdog_reload();
+		input_level = gpio_get_level(GPIO_HANDSHAKE_INPUT);
+	} while (input_level);
+	gpio_set_level(GPIO_HANDSHAKE_OUTPUT, 0);
+
+	return UNKNOWN;
+}
diff --git a/cts/common/dut_common.h b/cts/common/dut_common.h
new file mode 100644
index 0000000000..bd844499be
--- /dev/null
+++ b/cts/common/dut_common.h
@@ -0,0 +1,13 @@
+/* Copyright 2016 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef __DUT_COMMON_H
+#define __DUT_COMMON_H
+
+#include "cts_common.h"
+
+enum cts_error_code sync(void);
+
+#endif
diff --git a/cts/common/th_common.c b/cts/common/th_common.c
new file mode 100644
index 0000000000..1c75ef9dee
--- /dev/null
+++ b/cts/common/th_common.c
@@ -0,0 +1,35 @@
+/* Copyright 2016 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "gpio.h"
+#include "timer.h"
+#include "watchdog.h"
+#include "cts_common.h"
+
+/* Return SUCCESS if and only if we reach end of function
+ * Returning success here means sync was successful
+ */
+enum cts_error_code sync(void)
+{
+	int input_level;
+
+	gpio_set_level(GPIO_HANDSHAKE_OUTPUT, 0);
+	do {
+		watchdog_reload();
+		input_level = gpio_get_level(GPIO_HANDSHAKE_INPUT);
+	} while (input_level);
+	gpio_set_level(GPIO_HANDSHAKE_OUTPUT, 1);
+	do {
+		watchdog_reload();
+		input_level = gpio_get_level(GPIO_HANDSHAKE_INPUT);
+	} while (!input_level);
+	gpio_set_level(GPIO_HANDSHAKE_OUTPUT, 0);
+	do {
+		watchdog_reload();
+		input_level = gpio_get_level(GPIO_HANDSHAKE_INPUT);
+	} while (input_level);
+
+	return SUCCESS;
+}
diff --git a/cts/common/th_common.h b/cts/common/th_common.h
new file mode 100644
index 0000000000..0495e1048e
--- /dev/null
+++ b/cts/common/th_common.h
@@ -0,0 +1,13 @@
+/* Copyright 2016 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef __TH_COMMON_H
+#define __TH_COMMON_H
+
+#include "cts_common.h"
+
+enum cts_error_code sync(void);
+
+#endif
diff --git a/cts/gpio/dut.c b/cts/gpio/dut.c
index bdcd4938f7..7120a4da3e 100644
--- a/cts/gpio/dut.c
+++ b/cts/gpio/dut.c
@@ -3,11 +3,19 @@
  * found in the LICENSE file.
  */
 
+#include "common.h"
+#include "watchdog.h"
+#include "uart.h"
 #include "timer.h"
 #include "watchdog.h"
+#include "dut_common.h"
+#include "cts_common.h"
 
 void cts_task(void)
 {
+	sync();
+	CPRINTS("Successful Sync!");
+	uart_flush_output();
 	while (1) {
 		watchdog_reload();
 		sleep(1);
diff --git a/cts/gpio/th.c b/cts/gpio/th.c
index bdcd4938f7..7120a4da3e 100644
--- a/cts/gpio/th.c
+++ b/cts/gpio/th.c
@@ -3,11 +3,19 @@
  * found in the LICENSE file.
  */
 
+#include "common.h"
+#include "watchdog.h"
+#include "uart.h"
 #include "timer.h"
 #include "watchdog.h"
+#include "dut_common.h"
+#include "cts_common.h"
 
 void cts_task(void)
 {
+	sync();
+	CPRINTS("Successful Sync!");
+	uart_flush_output();
 	while (1) {
 		watchdog_reload();
 		sleep(1);