iteflash: exit DBGR mode after flashing

This change is separated from CL:344481.

We need a cold reset after flashing, but we kill 'servod' before
execute iteflash for each flashing process.

With this change, we can restart 'servod' again without errors.
And we are able to use dut-control to do a EC cold reset.

BRANCH=none
BUG=none
TEST=flashing completed, and wait for servo's cold reset.

Change-Id: Ifc242467211253fabcd733a971e999baa68a1026
Signed-off-by: Dino Li <Dino.Li@ite.com.tw>
Reviewed-on: https://chromium-review.googlesource.com/488002
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>

1 files changed, 21 insertions, 11 deletions

diff --git a/util/iteflash.c b/util/iteflash.c
index 82d2c9d3fb..cb583af64e 100644
--- a/util/iteflash.c
+++ b/util/iteflash.c
@@ -288,6 +288,11 @@ static int dbgr_reset(struct ftdi_context *ftdi)
 {
 	int ret = 0;
 
+	/* Reset CPU only, and we keep power state until flashing is done. */
+	ret |= i2c_write_byte(ftdi, 0x2f, 0x20);
+	ret |= i2c_write_byte(ftdi, 0x2e, 0x06);
+	ret |= i2c_write_byte(ftdi, 0x30, 0x40);
+
 	ret |= i2c_write_byte(ftdi, 0x27, 0x80);
 	if (ret < 0)
 		printf("DBGR RESET FAILED\n");
@@ -295,18 +300,23 @@ static int dbgr_reset(struct ftdi_context *ftdi)
 	return 0;
 }
 
-/* Do WatchDog Reset*/
-static int do_watchdog_reset(struct ftdi_context *ftdi)
+static int exit_dbgr_mode(struct ftdi_context *ftdi)
 {
+	uint8_t val;
 	int ret = 0;
 
-	ret |= i2c_write_byte(ftdi, 0x2f, 0x20);
-	ret |= i2c_write_byte(ftdi, 0x2e, 0x06);
-	ret |= i2c_write_byte(ftdi, 0x30, 0x4C);
-	ret |= i2c_write_byte(ftdi, 0x27, 0x80);
-
-	if (ret < 0)
-		printf("WATCHDOG RESET FAILED\n");
+	/* We have to exit dbgr mode so that EC won't hold I2C bus. */
+	ret |= i2c_write_byte(ftdi, 0x2f, 0x1c);
+	ret |= i2c_write_byte(ftdi, 0x2e, 0x08);
+	ret |= i2c_read_byte(ftdi, 0x30, &val);
+	ret |= i2c_write_byte(ftdi, 0x30, (val | (1 << 4)));
+	/*
+	 * NOTE:
+	 * We won't be able to send any commands to EC
+	 * if we have exit dbgr mode.
+	 * We do a cold reset for EC after flashing.
+	 */
+	printf("=== EXIT DBGR MODE %s ===\n", (ret < 0) ? "FAILED" : "DONE");
 
 	return 0;
 }
@@ -1090,8 +1100,8 @@ int main(int argc, char **argv)
 	ret = 0;
 terminate:
 
-	/* DO EC WATCHDOG RESET */
-	do_watchdog_reset(hnd);
+	/* Exit DBGR mode */
+	exit_dbgr_mode(hnd);
 
 	/* Close the FTDI USB handle */
 	ftdi_usb_close(hnd);