ADIv5 clean up AP fault handling

Pass up fault codes from various routines, so their callers
can clean up after failures, and remove the FIXME comments
highlighting those previously goofy code paths.

 dap_ap_{read,write}_reg_u32()
 dap_ap_write_reg()
 mem_ap_{read,write}_u32()
 mem_ap_{read,write}_atomic_u32()
 dap_setup_accessport()

Make dap_ap_write_reg_u32() just wrap dap_ap_write_reg(),
instead of cloning its core code (and broken fault handling).

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

src/target/arm_adi_v5.c

@@ -450,12 +450,14 @@ static int dap_ap_bankselect(struct swjdp_common *swjdp, uint32_t ap_reg)
 static int dap_ap_write_reg(struct swjdp_common *swjdp,
 		uint32_t reg_addr, uint8_t *out_value_buf)
 {
-	dap_ap_bankselect(swjdp, reg_addr);
+	int retval;
-	scan_inout_check(swjdp, JTAG_DP_APACC, reg_addr,
-			DPAP_WRITE, out_value_buf, NULL);
 
-	/* FIXME return fault code from above calls */
+	retval = dap_ap_bankselect(swjdp, reg_addr);
-	return ERROR_OK;
+	if (retval != ERROR_OK)
+		return retval;
+
+	return scan_inout_check(swjdp, JTAG_DP_APACC, reg_addr,
+			DPAP_WRITE, out_value_buf, NULL);
 }
 
 /**
@@ -477,12 +479,8 @@ int dap_ap_write_reg_u32(struct swjdp_common *swjdp,
 	uint8_t out_value_buf[4];
 
 	buf_set_u32(out_value_buf, 0, 32, value);
-	dap_ap_bankselect(swjdp, reg_addr);
+	return dap_ap_write_reg(swjdp,
-	scan_inout_check(swjdp, JTAG_DP_APACC, reg_addr,
+			reg_addr, out_value_buf);
-			DPAP_WRITE, out_value_buf, NULL);
-
-	/* FIXME return any fault code from above calls */
-	return ERROR_OK;
 }
 
 /**
@@ -501,12 +499,14 @@ int dap_ap_write_reg_u32(struct swjdp_common *swjdp,
 int dap_ap_read_reg_u32(struct swjdp_common *swjdp,
 		uint32_t reg_addr, uint32_t *value)
 {
-	dap_ap_bankselect(swjdp, reg_addr);
+	int retval;
-	scan_inout_check_u32(swjdp, JTAG_DP_APACC, reg_addr,
-			DPAP_READ, 0, value);
 
-	/* FIXME return any fault code from above calls */
+	retval = dap_ap_bankselect(swjdp, reg_addr);
-	return ERROR_OK;
+	if (retval != ERROR_OK)
+		return retval;
+
+	return scan_inout_check_u32(swjdp, JTAG_DP_APACC, reg_addr,
+			DPAP_READ, 0, value);
 }
 
 /**
@@ -533,19 +533,23 @@ int dap_ap_read_reg_u32(struct swjdp_common *swjdp,
  */
 int dap_setup_accessport(struct swjdp_common *swjdp, uint32_t csw, uint32_t tar)
 {
+	int retval;
+
 	csw = csw | CSW_DBGSWENABLE | CSW_MASTER_DEBUG | CSW_HPROT;
 	if (csw != swjdp->ap_csw_value)
 	{
 		/* LOG_DEBUG("DAP: Set CSW %x",csw); */
-		/* FIXME if this call fails, fail this procedure! */
+		retval = dap_ap_write_reg_u32(swjdp, AP_REG_CSW, csw);
-		dap_ap_write_reg_u32(swjdp, AP_REG_CSW, csw);
+		if (retval != ERROR_OK)
+			return retval;
 		swjdp->ap_csw_value = csw;
 	}
 	if (tar != swjdp->ap_tar_value)
 	{
 		/* LOG_DEBUG("DAP: Set TAR %x",tar); */
-		/* FIXME if this call fails, fail this procedure! */
+		retval = dap_ap_write_reg_u32(swjdp, AP_REG_TAR, tar);
-		dap_ap_write_reg_u32(swjdp, AP_REG_TAR, tar);
+		if (retval != ERROR_OK)
+			return retval;
 		swjdp->ap_tar_value = tar;
 	}
 	/* Disable TAR cache when autoincrementing */
@@ -568,17 +572,19 @@ int dap_setup_accessport(struct swjdp_common *swjdp, uint32_t csw, uint32_t tar)
 int mem_ap_read_u32(struct swjdp_common *swjdp, uint32_t address,
 		uint32_t *value)
 {
+	int retval;
+
 	swjdp->trans_mode = TRANS_MODE_COMPOSITE;
 
 	/* Use banked addressing (REG_BDx) to avoid some link traffic
 	 * (updating TAR) when reading several consecutive addresses.
 	 */
-	dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF,
+	retval = dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF,
 			address & 0xFFFFFFF0);
-	dap_ap_read_reg_u32(swjdp, AP_REG_BD0 | (address & 0xC), value);
+	if (retval != ERROR_OK)
+		return retval;
 
-	/* FIXME return any fault code from above calls */
+	return dap_ap_read_reg_u32(swjdp, AP_REG_BD0 | (address & 0xC), value);
-	return ERROR_OK;
 }
 
 /**
@@ -596,8 +602,11 @@ int mem_ap_read_u32(struct swjdp_common *swjdp, uint32_t address,
 int mem_ap_read_atomic_u32(struct swjdp_common *swjdp, uint32_t address,
 		uint32_t *value)
 {
-	mem_ap_read_u32(swjdp, address, value);
+	int retval;
-	/* FIXME return any fault code from above call */
+
+	retval = mem_ap_read_u32(swjdp, address, value);
+	if (retval != ERROR_OK)
+		return retval;
 
 	return jtagdp_transaction_endcheck(swjdp);
 }
@@ -616,17 +625,20 @@ int mem_ap_read_atomic_u32(struct swjdp_common *swjdp, uint32_t address,
 int mem_ap_write_u32(struct swjdp_common *swjdp, uint32_t address,
 		uint32_t value)
 {
+	int retval;
+
 	swjdp->trans_mode = TRANS_MODE_COMPOSITE;
 
 	/* Use banked addressing (REG_BDx) to avoid some link traffic
 	 * (updating TAR) when writing several consecutive addresses.
 	 */
-	dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF,
+	retval = dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF,
 			address & 0xFFFFFFF0);
-	dap_ap_write_reg_u32(swjdp, AP_REG_BD0 | (address & 0xC), value);
+	if (retval != ERROR_OK)
+		return retval;
 
-	/* FIXME return any fault code from above calls */
+	return dap_ap_write_reg_u32(swjdp, AP_REG_BD0 | (address & 0xC),
-	return ERROR_OK;
+			value);
 }
 
 /**
@@ -643,8 +655,10 @@ int mem_ap_write_u32(struct swjdp_common *swjdp, uint32_t address,
 int mem_ap_write_atomic_u32(struct swjdp_common *swjdp, uint32_t address,
 		uint32_t value)
 {
-	mem_ap_write_u32(swjdp, address, value);
+	int retval = mem_ap_write_u32(swjdp, address, value);
-	/* FIXME return any fault code from above call */
+
+	if (retval != ERROR_OK)
+		return retval;
 
 	return jtagdp_transaction_endcheck(swjdp);
 }