arm_adi_v5: Add ability to ignore the CSYSPWRUPACK bit

The CTRL/STAT register in the ARM DAP DP has a debug power up
ack bit and a system power up ack bit. Some devices do not set
the system power up ack bit until sometime later. To avoid having
the initial target examination fail due to this or to have a
sticky bit error report claim power failure due to this a user
can now specify that this bit should be ignored.

Change-Id: I2451234bbe904984e29562ef6f616cc6d6f60732
Signed-off-by: Eric Katzfey <eric.katzfey@mentalbee.com>
Signed-off-by: Matthias Welwarsky <matthias.welwarsky@sysgo.com>
Reviewed-on: http://openocd.zylin.com/3710
Tested-by: jenkins
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>

4 files changed, 22 insertions, 9 deletions

diff --git a/src/target/adi_v5_jtag.c b/src/target/adi_v5_jtag.c
index dc023790..8c206115 100644
--- a/src/target/adi_v5_jtag.c
+++ b/src/target/adi_v5_jtag.c
@@ -553,7 +553,7 @@ static int jtagdp_overrun_check(struct adiv5_dap *dap)
 static int jtagdp_transaction_endcheck(struct adiv5_dap *dap)
 {
 	int retval;
-	uint32_t ctrlstat;
+	uint32_t ctrlstat, pwrmask;
 
 	/* too expensive to call keep_alive() here */
 
@@ -571,8 +571,10 @@ static int jtagdp_transaction_endcheck(struct adiv5_dap *dap)
 	if (ctrlstat & SSTICKYERR) {
 		LOG_DEBUG("jtag-dp: CTRL/STAT 0x%" PRIx32, ctrlstat);
 		/* Check power to debug regions */
-		if ((ctrlstat & (CDBGPWRUPREQ | CDBGPWRUPACK | CSYSPWRUPREQ | CSYSPWRUPACK)) !=
-						(CDBGPWRUPREQ | CDBGPWRUPACK | CSYSPWRUPREQ | CSYSPWRUPACK)) {
+		pwrmask = CDBGPWRUPREQ | CDBGPWRUPACK | CSYSPWRUPREQ;
+		if (!dap->ignore_syspwrupack)
+			pwrmask |= CSYSPWRUPACK;
+		if ((ctrlstat & pwrmask) != pwrmask) {
 			LOG_ERROR("Debug regions are unpowered, an unexpected reset might have happened");
 			dap->do_reconnect = true;
 		}
diff --git a/src/target/arm_adi_v5.c b/src/target/arm_adi_v5.c
index 2b7d7b22..f9b51cde 100644
--- a/src/target/arm_adi_v5.c
+++ b/src/target/arm_adi_v5.c
@@ -676,12 +676,14 @@ int dap_dp_init(struct adiv5_dap *dap)
 	if (retval != ERROR_OK)
 		return retval;
 
-	LOG_DEBUG("DAP: wait CSYSPWRUPACK");
-	retval = dap_dp_poll_register(dap, DP_CTRL_STAT,
-				      CSYSPWRUPACK, CSYSPWRUPACK,
-				      DAP_POWER_DOMAIN_TIMEOUT);
-	if (retval != ERROR_OK)
-		return retval;
+	if (!dap->ignore_syspwrupack) {
+		LOG_DEBUG("DAP: wait CSYSPWRUPACK");
+		retval = dap_dp_poll_register(dap, DP_CTRL_STAT,
+					      CSYSPWRUPACK, CSYSPWRUPACK,
+					      DAP_POWER_DOMAIN_TIMEOUT);
+		if (retval != ERROR_OK)
+			return retval;
+	}
 
 	retval = dap_queue_dp_read(dap, DP_CTRL_STAT, NULL);
 	if (retval != ERROR_OK)
diff --git a/src/target/arm_adi_v5.h b/src/target/arm_adi_v5.h
index aa5fa42f..bc561165 100644
--- a/src/target/arm_adi_v5.h
+++ b/src/target/arm_adi_v5.h
@@ -244,6 +244,10 @@ struct adiv5_dap {
 	 * should be performed before the next access.
 	 */
 	bool do_reconnect;
+
+	/** Flag saying whether to ignore the syspwrupack flag in DAP. Some devices
+	 *  do not set this bit until later in the bringup sequence */
+	bool ignore_syspwrupack;
 };
 
 /**
diff --git a/src/target/arm_dap.c b/src/target/arm_dap.c
index 692feb32..797feb5b 100644
--- a/src/target/arm_dap.c
+++ b/src/target/arm_dap.c
@@ -141,10 +141,12 @@ int dap_cleanup_all(void)
 
 enum dap_cfg_param {
 	CFG_CHAIN_POSITION,
+	CFG_IGNORE_SYSPWRUPACK,
 };
 
 static const Jim_Nvp nvp_config_opts[] = {
 	{ .name = "-chain-position",   .value = CFG_CHAIN_POSITION },
+	{ .name = "-ignore-syspwrupack", .value = CFG_IGNORE_SYSPWRUPACK },
 	{ .name = NULL, .value = -1 }
 };
 
@@ -177,6 +179,9 @@ static int dap_configure(Jim_GetOptInfo *goi, struct arm_dap_object *dap)
 			/* loop for more */
 			break;
 		}
+		case CFG_IGNORE_SYSPWRUPACK:
+			dap->dap.ignore_syspwrupack = true;
+			break;
 		default:
 			break;
 		}