From: Evan Hunter <ehunter@broadcom.com>
Date: Thu, 11 Oct 2012 20:24:11 +0000 (+1100)
Subject: Ensure Cortex-M reset wakes device from sleep (wfi/wfe)
X-Git-Url: https://git.gag.com/?p=fw%2Fopenocd;a=commitdiff_plain;h=6663a788a53ee38f2d6950fe7802eae7855e01f3

Ensure Cortex-M reset wakes device from sleep (wfi/wfe)

Change-Id: Idb52ca3123bb3e2f7863ba1b82ac9b176d7cb094
Signed-off-by: Evan Hunter <ehunter@broadcom.com>
Reviewed-on: http://openocd.zylin.com/833
Tested-by: jenkins
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>
---

diff --git a/src/target/cortex_m.c b/src/target/cortex_m.c
index 74505a85e..81d6ccf4f 100644
--- a/src/target/cortex_m.c
+++ b/src/target/cortex_m.c
@@ -973,6 +973,14 @@ static int cortex_m3_assert_reset(struct target *target)
 			return retval;
 	}
 
+	/* If the processor is sleeping in a WFI or WFE instruction, the
+	 * C_HALT bit must be asserted to regain control */
+	if (cortex_m3->dcb_dhcsr & S_SLEEP) {
+		retval = mem_ap_write_u32(swjdp, DCB_DHCSR, DBGKEY | C_HALT | C_DEBUGEN);
+		if (retval != ERROR_OK)
+			return retval;
+	}
+
 	retval = mem_ap_write_u32(swjdp, DCB_DCRDR, 0);
 	if (retval != ERROR_OK)
 		return retval;