armv7m: add generic trace support (TPIU, ITM, etc.)

This provides support for various trace-related subsystems in a
generic and expandable way.

Change-Id: I3a27fa7b8cfb111753088bb8c3d760dd12d1395f
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-on: http://openocd.zylin.com/2538
Tested-by: jenkins

1 files changed, 87 insertions, 0 deletions

diff --git a/src/target/armv7m_trace.h b/src/target/armv7m_trace.h
new file mode 100644
index 00000000..96c18958
--- /dev/null
+++ b/src/target/armv7m_trace.h
@@ -0,0 +1,87 @@
+/***************************************************************************
+ *   Copyright (C) 2015  Paul Fertser <fercerpav@gmail.com>                *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ ***************************************************************************/
+
+#ifndef ARMV7M_TRACE_H
+#define ARMV7M_TRACE_H
+
+#include <command.h>
+
+/**
+ * @file
+ * Holds the interface to TPIU, ITM and DWT configuration functions.
+ */
+
+enum trace_config_type {
+	DISABLED,	/**< tracing is disabled */
+	EXTERNAL,	/**< trace output is captured externally */
+	INTERNAL	/**< trace output is handled by OpenOCD adapter driver */
+};
+
+enum tpio_pin_protocol {
+	SYNC,			/**< synchronous trace output */
+	ASYNC_MANCHESTER,	/**< asynchronous output with Manchester coding */
+	ASYNC_UART		/**< asynchronous output with NRZ coding */
+};
+
+enum itm_ts_prescaler {
+	ITM_TS_PRESCALE1,	/**< no prescaling for the timestamp counter */
+	ITM_TS_PRESCALE4,	/**< refclock divided by 4 for the timestamp counter */
+	ITM_TS_PRESCALE16,	/**< refclock divided by 16 for the timestamp counter */
+	ITM_TS_PRESCALE64,	/**< refclock divided by 64 for the timestamp counter */
+};
+
+struct armv7m_trace_config {
+	/** Currently active trace capture mode */
+	enum trace_config_type config_type;
+
+	/** Currently active trace output mode */
+	enum tpio_pin_protocol pin_protocol;
+	/** TPIU formatter enable/disable (in async mode) */
+	bool formatter;
+	/** Synchronous output port width */
+	uint32_t port_size;
+
+	/** Bitmask of currenty enabled ITM stimuli */
+	uint32_t itm_ter[8];
+	/** Identifier for multi-source trace stream formatting */
+	unsigned int trace_bus_id;
+	/** Prescaler for the timestamp counter */
+	enum itm_ts_prescaler itm_ts_prescale;
+	/** Enable differential timestamps */
+	bool itm_diff_timestamps;
+	/** Enable async timestamps model */
+	bool itm_async_timestamps;
+	/** Enable synchronisation packet transmission (for sync port only) */
+	bool itm_synchro_packets;
+
+	/** Current frequency of TRACECLKIN (usually matches HCLK) */
+	unsigned int traceclkin_freq;
+	/** Current frequency of trace port */
+	unsigned int trace_freq;
+	/** Handle to output trace data in INTERNAL capture mode */
+	FILE *trace_file;
+};
+
+extern const struct command_registration armv7m_trace_command_handlers[];
+
+/**
+ * Configure hardware accordingly to the current TPIU target settings
+ */
+int armv7m_trace_tpiu_config(struct target *target);
+/**
+ * Configure hardware accordingly to the current ITM target settings
+ */
+int armv7m_trace_itm_config(struct target *target);
+
+#endif