perf tools: Add functionality to communicate with the openCSD decoder

This patch adds functions to communicate with the openCSD trace decoder,
more specifically to access program memory, fetch trace packets and
reset the decoder.

Co-authored-by: Tor Jeremiassen <tor@ti.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mike Leach <mike.leach@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1516211539-5166-7-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/cs-etm-decoder/cs-etm-decoder.c

@@ -45,6 +45,66 @@ struct cs_etm_decoder {
 	struct cs_etm_packet packet_buffer[MAX_BUFFER];
 };
 
+static u32
+cs_etm_decoder__mem_access(const void *context,
+			   const ocsd_vaddr_t address,
+			   const ocsd_mem_space_acc_t mem_space __maybe_unused,
+			   const u32 req_size,
+			   u8 *buffer)
+{
+	struct cs_etm_decoder *decoder = (struct cs_etm_decoder *) context;
+
+	return decoder->mem_access(decoder->data,
+				   address,
+				   req_size,
+				   buffer);
+}
+
+int cs_etm_decoder__add_mem_access_cb(struct cs_etm_decoder *decoder,
+				      u64 start, u64 end,
+				      cs_etm_mem_cb_type cb_func)
+{
+	decoder->mem_access = cb_func;
+
+	if (ocsd_dt_add_callback_mem_acc(decoder->dcd_tree, start, end,
+					 OCSD_MEM_SPACE_ANY,
+					 cs_etm_decoder__mem_access, decoder))
+		return -1;
+
+	return 0;
+}
+
+int cs_etm_decoder__reset(struct cs_etm_decoder *decoder)
+{
+	ocsd_datapath_resp_t dp_ret;
+
+	dp_ret = ocsd_dt_process_data(decoder->dcd_tree, OCSD_OP_RESET,
+				      0, 0, NULL, NULL);
+	if (OCSD_DATA_RESP_IS_FATAL(dp_ret))
+		return -1;
+
+	return 0;
+}
+
+int cs_etm_decoder__get_packet(struct cs_etm_decoder *decoder,
+			       struct cs_etm_packet *packet)
+{
+	if (!decoder || !packet)
+		return -EINVAL;
+
+	/* Nothing to do, might as well just return */
+	if (decoder->packet_count == 0)
+		return 0;
+
+	*packet = decoder->packet_buffer[decoder->head];
+
+	decoder->head = (decoder->head + 1) & (MAX_BUFFER - 1);
+
+	decoder->packet_count--;
+
+	return 1;
+}
+
 static void cs_etm_decoder__gen_etmv4_config(struct cs_etm_trace_params *params,
 					     ocsd_etmv4_cfg *config)
 {

tools/perf/util/cs-etm-decoder/cs-etm-decoder.h

@@ -93,4 +93,13 @@ cs_etm_decoder__new(int num_cpu,
 
 void cs_etm_decoder__free(struct cs_etm_decoder *decoder);
 
+int cs_etm_decoder__add_mem_access_cb(struct cs_etm_decoder *decoder,
+				      u64 start, u64 end,
+				      cs_etm_mem_cb_type cb_func);
+
+int cs_etm_decoder__get_packet(struct cs_etm_decoder *decoder,
+			       struct cs_etm_packet *packet);
+
+int cs_etm_decoder__reset(struct cs_etm_decoder *decoder);
+
 #endif /* INCLUDE__CS_ETM_DECODER_H__ */