mips: add breakpoint support for EJTAG 2.0

EJTAG 1.5, 2.0 and 2.5 have different breakpoint register addresses.
This patch add support of EJTAG 2.0, which is part some broadcom
SoCs.

This work was testet on Broadcom BCM7401.

Change-Id: I4b0ee23871fa9205f9001b7c9165e7b6ebe9ccbf
Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Reviewed-on: http://openocd.zylin.com/1464
Tested-by: jenkins
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>

4 files changed, 152 insertions, 23 deletions

diff --git a/src/target/mips32.c b/src/target/mips32.c
index 16988b5..1067f7b 100644
--- a/src/target/mips32.c
+++ b/src/target/mips32.c
@@ -472,11 +472,12 @@ int mips32_examine(struct target *target)
 static int mips32_configure_ibs(struct target *target)
 {
 	struct mips32_common *mips32 = target_to_mips32(target);
+	struct mips_ejtag *ejtag_info = &mips32->ejtag_info;
 	int retval, i;
 	uint32_t bpinfo;
 
 	/* get number of inst breakpoints */
-	retval = target_read_u32(target, EJTAG_IBS, &bpinfo);
+	retval = target_read_u32(target, ejtag_info->ejtag_ibs_addr, &bpinfo);
 	if (retval != ERROR_OK)
 		return retval;
 
@@ -487,21 +488,23 @@ static int mips32_configure_ibs(struct target *target)
 
 	for (i = 0; i < mips32->num_inst_bpoints; i++)
 		mips32->inst_break_list[i].reg_address =
-			EJTAG_IBA1 + (0x100 * i);
+			ejtag_info->ejtag_iba0_addr +
+			(ejtag_info->ejtag_iba_step_size * i);
 
 	/* clear IBIS reg */
-	retval = target_write_u32(target, EJTAG_IBS, 0);
+	retval = target_write_u32(target, ejtag_info->ejtag_ibs_addr, 0);
 	return retval;
 }
 
 static int mips32_configure_dbs(struct target *target)
 {
 	struct mips32_common *mips32 = target_to_mips32(target);
+	struct mips_ejtag *ejtag_info = &mips32->ejtag_info;
 	int retval, i;
 	uint32_t bpinfo;
 
 	/* get number of data breakpoints */
-	retval = target_read_u32(target, EJTAG_DBS, &bpinfo);
+	retval = target_read_u32(target, ejtag_info->ejtag_dbs_addr, &bpinfo);
 	if (retval != ERROR_OK)
 		return retval;
 
@@ -512,10 +515,11 @@ static int mips32_configure_dbs(struct target *target)
 
 	for (i = 0; i < mips32->num_data_bpoints; i++)
 		mips32->data_break_list[i].reg_address =
-			EJTAG_DBA1 + (0x100 * i);
+			ejtag_info->ejtag_dba0_addr +
+			(ejtag_info->ejtag_dba_step_size * i);
 
 	/* clear DBIS reg */
-	retval = target_write_u32(target, EJTAG_DBS, 0);
+	retval = target_write_u32(target, ejtag_info->ejtag_dbs_addr, 0);
 	return retval;
 }
 
@@ -523,6 +527,7 @@ int mips32_configure_break_unit(struct target *target)
 {
 	/* get pointers to arch-specific information */
 	struct mips32_common *mips32 = target_to_mips32(target);
+	struct mips_ejtag *ejtag_info = &mips32->ejtag_info;
 	int retval;
 	uint32_t dcr;
 
@@ -534,6 +539,11 @@ int mips32_configure_break_unit(struct target *target)
 	if (retval != ERROR_OK)
 		return retval;
 
+	/* EJTAG 2.0 does not specify EJTAG_DCR_IB and EJTAG_DCR_DB bits,
+	 * assume IB and DB registers are always present. */
+	if (ejtag_info->ejtag_version == EJTAG_VERSION_20)
+		dcr |= EJTAG_DCR_IB | EJTAG_DCR_DB;
+
 	if (dcr & EJTAG_DCR_IB) {
 		retval = mips32_configure_ibs(target);
 		if (retval != ERROR_OK)
diff --git a/src/target/mips_ejtag.c b/src/target/mips_ejtag.c
index 8574814..3457b78 100644
--- a/src/target/mips_ejtag.c
+++ b/src/target/mips_ejtag.c
@@ -303,6 +303,45 @@ int mips_ejtag_exit_debug(struct mips_ejtag *ejtag_info)
 	return ctx.retval;
 }
 
+/* mips_ejtag_init_mmr - asign Memory-Mapped Registers depending
+ *			on EJTAG version.
+ */
+static void mips_ejtag_init_mmr(struct mips_ejtag *ejtag_info)
+{
+	if (ejtag_info->ejtag_version == EJTAG_VERSION_20) {
+		ejtag_info->ejtag_ibs_addr	= EJTAG_V20_IBS;
+		ejtag_info->ejtag_iba0_addr	= EJTAG_V20_IBA0;
+		ejtag_info->ejtag_ibc_offs	= EJTAG_V20_IBC_OFFS;
+		ejtag_info->ejtag_ibm_offs	= EJTAG_V20_IBM_OFFS;
+
+		ejtag_info->ejtag_dbs_addr	= EJTAG_V20_DBS;
+		ejtag_info->ejtag_dba0_addr	= EJTAG_V20_DBA0;
+		ejtag_info->ejtag_dbc_offs	= EJTAG_V20_DBC_OFFS;
+		ejtag_info->ejtag_dbm_offs	= EJTAG_V20_DBM_OFFS;
+		ejtag_info->ejtag_dbv_offs	= EJTAG_V20_DBV_OFFS;
+
+		ejtag_info->ejtag_iba_step_size	= EJTAG_V20_IBAn_STEP;
+		ejtag_info->ejtag_dba_step_size	= EJTAG_V20_DBAn_STEP;
+	} else {
+		ejtag_info->ejtag_ibs_addr	= EJTAG_V25_IBS;
+		ejtag_info->ejtag_iba0_addr	= EJTAG_V25_IBA0;
+		ejtag_info->ejtag_ibm_offs	= EJTAG_V25_IBM_OFFS;
+		ejtag_info->ejtag_ibasid_offs	= EJTAG_V25_IBASID_OFFS;
+		ejtag_info->ejtag_ibc_offs	= EJTAG_V25_IBC_OFFS;
+
+		ejtag_info->ejtag_dbs_addr	= EJTAG_V25_DBS;
+		ejtag_info->ejtag_dba0_addr	= EJTAG_V25_DBA0;
+		ejtag_info->ejtag_dbm_offs	= EJTAG_V25_DBM_OFFS;
+		ejtag_info->ejtag_dbasid_offs	= EJTAG_V25_DBASID_OFFS;
+		ejtag_info->ejtag_dbc_offs	= EJTAG_V25_DBC_OFFS;
+		ejtag_info->ejtag_dbv_offs	= EJTAG_V25_DBV_OFFS;
+
+		ejtag_info->ejtag_iba_step_size	= EJTAG_V25_IBAn_STEP;
+		ejtag_info->ejtag_dba_step_size	= EJTAG_V25_DBAn_STEP;
+	}
+}
+
+
 int mips_ejtag_init(struct mips_ejtag *ejtag_info)
 {
 	int retval;
@@ -354,6 +393,8 @@ int mips_ejtag_init(struct mips_ejtag *ejtag_info)
 	ejtag_info->ejtag_ctrl = EJTAG_CTRL_ROCC | EJTAG_CTRL_PRACC | EJTAG_CTRL_PROBEN | EJTAG_CTRL_SETDEV;
 	ejtag_info->fast_access_save = -1;
 
+	mips_ejtag_init_mmr(ejtag_info);
+
 	return ERROR_OK;
 }
 
diff --git a/src/target/mips_ejtag.h b/src/target/mips_ejtag.h
index 760a7c5..db20e9d 100644
--- a/src/target/mips_ejtag.h
+++ b/src/target/mips_ejtag.h
@@ -113,10 +113,34 @@
 #define EJTAG_DCR_MP			(1 << 2)
 
 /* breakpoint support */
-#define EJTAG_IBS				0xFF301000
-#define EJTAG_IBA1				0xFF301100
-#define EJTAG_DBS				0xFF302000
-#define EJTAG_DBA1				0xFF302100
+/* EJTAG_V20_* was tested on Broadcom BCM7401
+ * and may or will differ with other hardware. For example EZ4021-FC. */
+#define EJTAG_V20_IBS			0xFF300004
+#define EJTAG_V20_IBA0			0xFF300100
+#define EJTAG_V20_IBC_OFFS		0x4	/* IBC Offset */
+#define EJTAG_V20_IBM_OFFS		0x8
+#define EJTAG_V20_IBAn_STEP		0x10	/* Offset for next channel */
+#define EJTAG_V20_DBS			0xFF30008
+#define EJTAG_V20_DBA0			0xFF300200
+#define EJTAG_V20_DBC_OFFS		0x4
+#define EJTAG_V20_DBM_OFFS		0x8
+#define EJTAG_V20_DBV_OFFS		0xc
+#define EJTAG_V20_DBAn_STEP		0x10
+
+#define EJTAG_V25_IBS			0xFF301000
+#define EJTAG_V25_IBA0			0xFF301100
+#define EJTAG_V25_IBM_OFFS		0x8
+#define EJTAG_V25_IBASID_OFFS		0x10
+#define EJTAG_V25_IBC_OFFS		0x18
+#define EJTAG_V25_IBAn_STEP		0x100
+#define EJTAG_V25_DBS			0xFF302000
+#define EJTAG_V25_DBA0			0xFF302100
+#define EJTAG_V25_DBM_OFFS		0x8
+#define EJTAG_V25_DBASID_OFFS		0x10
+#define EJTAG_V25_DBC_OFFS		0x18
+#define EJTAG_V25_DBV_OFFS		0x20
+#define EJTAG_V25_DBAn_STEP		0x100
+
 #define	EJTAG_DBCn_NOSB			(1 << 13)
 #define	EJTAG_DBCn_NOLB			(1 << 12)
 #define	EJTAG_DBCn_BLM_MASK		0xff
@@ -141,6 +165,25 @@ struct mips_ejtag {
 	unsigned scan_delay;
 	int mode;
 	unsigned int ejtag_version;
+
+	/* Memory-Mapped Registers. This addresses are not same on different
+	 * EJTAG versions. */
+	uint32_t ejtag_ibs_addr;	/* Instruction Address Break Status */
+	uint32_t ejtag_iba0_addr;	/* IAB channel 0 */
+	uint32_t ejtag_ibc_offs;	/* IAB Control offset */
+	uint32_t ejtag_ibm_offs;	/* IAB Mask offset */
+	uint32_t ejtag_ibasid_offs;	/* IAB ASID (4Kc) */
+
+	uint32_t ejtag_dbs_addr;	/* Data Address Break Status Register */
+	uint32_t ejtag_dba0_addr;	/* DAB channel 0 */
+	uint32_t ejtag_dbc_offs;	/* DAB Control offset */
+	uint32_t ejtag_dbm_offs;	/* DAB Mask offset */
+	uint32_t ejtag_dbv_offs;	/* DAB Value offset */
+	uint32_t ejtag_dbasid_offs;	/* DAB ASID (4Kc) */
+
+	uint32_t ejtag_iba_step_size;
+	uint32_t ejtag_dba_step_size;	/* siez of step till next
+					 * *DBAn register. */
 };
 
 void mips_ejtag_set_instr(struct mips_ejtag *ejtag_info,
diff --git a/src/target/mips_m4k.c b/src/target/mips_m4k.c
index fc2a3f8..49edad1 100644
--- a/src/target/mips_m4k.c
+++ b/src/target/mips_m4k.c
@@ -51,30 +51,36 @@ static int mips_m4k_bulk_write_memory(struct target *target, uint32_t address,
 
 static int mips_m4k_examine_debug_reason(struct target *target)
 {
+	struct mips32_common *mips32 = target_to_mips32(target);
+	struct mips_ejtag *ejtag_info = &mips32->ejtag_info;
 	uint32_t break_status;
 	int retval;
 
 	if ((target->debug_reason != DBG_REASON_DBGRQ)
 		&& (target->debug_reason != DBG_REASON_SINGLESTEP)) {
 		/* get info about inst breakpoint support */
-		retval = target_read_u32(target, EJTAG_IBS, &break_status);
+		retval = target_read_u32(target,
+			ejtag_info->ejtag_ibs_addr, &break_status);
 		if (retval != ERROR_OK)
 			return retval;
 		if (break_status & 0x1f) {
 			/* we have halted on a  breakpoint */
-			retval = target_write_u32(target, EJTAG_IBS, 0);
+			retval = target_write_u32(target,
+				ejtag_info->ejtag_ibs_addr, 0);
 			if (retval != ERROR_OK)
 				return retval;
 			target->debug_reason = DBG_REASON_BREAKPOINT;
 		}
 
 		/* get info about data breakpoint support */
-		retval = target_read_u32(target, EJTAG_DBS, &break_status);
+		retval = target_read_u32(target,
+			ejtag_info->ejtag_dbs_addr, &break_status);
 		if (retval != ERROR_OK)
 			return retval;
 		if (break_status & 0x1f) {
 			/* we have halted on a  breakpoint */
-			retval = target_write_u32(target, EJTAG_DBS, 0);
+			retval = target_write_u32(target,
+				ejtag_info->ejtag_dbs_addr, 0);
 			if (retval != ERROR_OK)
 				return retval;
 			target->debug_reason = DBG_REASON_WATCHPOINT;
@@ -587,6 +593,7 @@ static int mips_m4k_set_breakpoint(struct target *target,
 		struct breakpoint *breakpoint)
 {
 	struct mips32_common *mips32 = target_to_mips32(target);
+	struct mips_ejtag *ejtag_info = &mips32->ejtag_info;
 	struct mips32_comparator *comparator_list = mips32->inst_break_list;
 	int retval;
 
@@ -608,10 +615,19 @@ static int mips_m4k_set_breakpoint(struct target *target,
 		breakpoint->set = bp_num + 1;
 		comparator_list[bp_num].used = 1;
 		comparator_list[bp_num].bp_value = breakpoint->address;
+
+		/* EJTAG 2.0 uses 30bit IBA. First 2 bits are reserved.
+		 * Warning: there is no IB ASID registers in 2.0.
+		 * Do not set it! :) */
+		if (ejtag_info->ejtag_version == EJTAG_VERSION_20)
+			comparator_list[bp_num].bp_value &= 0xFFFFFFFC;
+
 		target_write_u32(target, comparator_list[bp_num].reg_address,
 				comparator_list[bp_num].bp_value);
-		target_write_u32(target, comparator_list[bp_num].reg_address + 0x08, 0x00000000);
-		target_write_u32(target, comparator_list[bp_num].reg_address + 0x18, 1);
+		target_write_u32(target, comparator_list[bp_num].reg_address +
+				 ejtag_info->ejtag_ibm_offs, 0x00000000);
+		target_write_u32(target, comparator_list[bp_num].reg_address +
+				 ejtag_info->ejtag_ibc_offs, 1);
 		LOG_DEBUG("bpid: %d, bp_num %i bp_value 0x%" PRIx32 "",
 				  breakpoint->unique_id,
 				  bp_num, comparator_list[bp_num].bp_value);
@@ -668,6 +684,7 @@ static int mips_m4k_unset_breakpoint(struct target *target,
 {
 	/* get pointers to arch-specific information */
 	struct mips32_common *mips32 = target_to_mips32(target);
+	struct mips_ejtag *ejtag_info = &mips32->ejtag_info;
 	struct mips32_comparator *comparator_list = mips32->inst_break_list;
 	int retval;
 
@@ -688,7 +705,8 @@ static int mips_m4k_unset_breakpoint(struct target *target,
 				bp_num);
 		comparator_list[bp_num].used = 0;
 		comparator_list[bp_num].bp_value = 0;
-		target_write_u32(target, comparator_list[bp_num].reg_address + 0x18, 0);
+		target_write_u32(target, comparator_list[bp_num].reg_address +
+				 ejtag_info->ejtag_ibc_offs, 0);
 
 	} else {
 		/* restore original instruction (kept in target endianness) */
@@ -777,6 +795,7 @@ static int mips_m4k_set_watchpoint(struct target *target,
 		struct watchpoint *watchpoint)
 {
 	struct mips32_common *mips32 = target_to_mips32(target);
+	struct mips_ejtag *ejtag_info = &mips32->ejtag_info;
 	struct mips32_comparator *comparator_list = mips32->data_break_list;
 	int wp_num = 0;
 	/*
@@ -826,11 +845,25 @@ static int mips_m4k_set_watchpoint(struct target *target,
 	watchpoint->set = wp_num + 1;
 	comparator_list[wp_num].used = 1;
 	comparator_list[wp_num].bp_value = watchpoint->address;
-	target_write_u32(target, comparator_list[wp_num].reg_address, comparator_list[wp_num].bp_value);
-	target_write_u32(target, comparator_list[wp_num].reg_address + 0x08, 0x00000000);
-	target_write_u32(target, comparator_list[wp_num].reg_address + 0x10, 0x00000000);
-	target_write_u32(target, comparator_list[wp_num].reg_address + 0x18, enable);
-	target_write_u32(target, comparator_list[wp_num].reg_address + 0x20, 0);
+
+	/* EJTAG 2.0 uses 29bit DBA. First 3 bits are reserved.
+	 * There is as well no ASID register support. */
+	if (ejtag_info->ejtag_version == EJTAG_VERSION_20)
+		comparator_list[wp_num].bp_value &= 0xFFFFFFF8;
+	else
+		target_write_u32(target, comparator_list[wp_num].reg_address +
+			 ejtag_info->ejtag_dbasid_offs, 0x00000000);
+
+	target_write_u32(target, comparator_list[wp_num].reg_address,
+			 comparator_list[wp_num].bp_value);
+	target_write_u32(target, comparator_list[wp_num].reg_address +
+			 ejtag_info->ejtag_dbm_offs, 0x00000000);
+
+	target_write_u32(target, comparator_list[wp_num].reg_address +
+			 ejtag_info->ejtag_dbc_offs, enable);
+	/* TODO: probably this value is ignored on 2.0 */
+	target_write_u32(target, comparator_list[wp_num].reg_address +
+			 ejtag_info->ejtag_dbv_offs, 0);
 	LOG_DEBUG("wp_num %i bp_value 0x%" PRIx32 "", wp_num, comparator_list[wp_num].bp_value);
 
 	return ERROR_OK;
@@ -841,6 +874,7 @@ static int mips_m4k_unset_watchpoint(struct target *target,
 {
 	/* get pointers to arch-specific information */
 	struct mips32_common *mips32 = target_to_mips32(target);
+	struct mips_ejtag *ejtag_info = &mips32->ejtag_info;
 	struct mips32_comparator *comparator_list = mips32->data_break_list;
 
 	if (!watchpoint->set) {
@@ -855,7 +889,8 @@ static int mips_m4k_unset_watchpoint(struct target *target,
 	}
 	comparator_list[wp_num].used = 0;
 	comparator_list[wp_num].bp_value = 0;
-	target_write_u32(target, comparator_list[wp_num].reg_address + 0x18, 0);
+	target_write_u32(target, comparator_list[wp_num].reg_address +
+			 ejtag_info->ejtag_dbc_offs, 0);
 	watchpoint->set = 0;
 
 	return ERROR_OK;