ASoC: SOF: Implement Probe IPC API

Add all required types and methods to support each and every request
that driver could sent to firmware. Probe is one of SOF firmware
features which allows for data extraction and injection directly from
or to DMA stream.

Exposes eight IPCs:
- addition and removal of injection DMAs
- addition and removal of probe points
- info retrieval of injection DMAs and probe points
- probe initialization and cleanup

Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200218143924.10565-5-cezary.rojewski@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

include/sound/sof/header.h

@@ -51,6 +51,7 @@
 #define SOF_IPC_GLB_TRACE_MSG			SOF_GLB_TYPE(0x9U)
 #define SOF_IPC_GLB_GDB_DEBUG                   SOF_GLB_TYPE(0xAU)
 #define SOF_IPC_GLB_TEST_MSG			SOF_GLB_TYPE(0xBU)
+#define SOF_IPC_GLB_PROBE			SOF_GLB_TYPE(0xCU)
 
 /*
  * DSP Command Message Types
@@ -102,6 +103,16 @@
 #define SOF_IPC_STREAM_VORBIS_PARAMS		SOF_CMD_TYPE(0x010)
 #define SOF_IPC_STREAM_VORBIS_FREE		SOF_CMD_TYPE(0x011)
 
+/* probe */
+#define SOF_IPC_PROBE_INIT			SOF_CMD_TYPE(0x001)
+#define SOF_IPC_PROBE_DEINIT			SOF_CMD_TYPE(0x002)
+#define SOF_IPC_PROBE_DMA_ADD			SOF_CMD_TYPE(0x003)
+#define SOF_IPC_PROBE_DMA_INFO			SOF_CMD_TYPE(0x004)
+#define SOF_IPC_PROBE_DMA_REMOVE		SOF_CMD_TYPE(0x005)
+#define SOF_IPC_PROBE_POINT_ADD		SOF_CMD_TYPE(0x006)
+#define SOF_IPC_PROBE_POINT_INFO		SOF_CMD_TYPE(0x007)
+#define SOF_IPC_PROBE_POINT_REMOVE		SOF_CMD_TYPE(0x008)
+
 /* trace */
 #define SOF_IPC_TRACE_DMA_PARAMS		SOF_CMD_TYPE(0x001)
 #define SOF_IPC_TRACE_DMA_POSITION		SOF_CMD_TYPE(0x002)

sound/soc/sof/Kconfig

@@ -41,6 +41,14 @@ config SND_SOC_SOF_OF
 	  required to enable i.MX8 devices.
 	  Say Y if you need this option. If unsure select "N".
 
+config SND_SOC_SOF_DEBUG_PROBES
+	bool "SOF enable data probing"
+	help
+	  This option enables the data probing feature that can be used to
+	  gather data directly from specific points of the audio pipeline.
+	  Say Y if you want to enable probes.
+	  If unsure, select "N".
+
 config SND_SOC_SOF_DEVELOPER_SUPPORT
 	bool "SOF developer options support"
 	depends on EXPERT

sound/soc/sof/Makefile

@@ -2,6 +2,7 @@
 
 snd-sof-objs := core.o ops.o loader.o ipc.o pcm.o pm.o debug.o topology.o\
 		control.o trace.o utils.o sof-audio.o
+snd-sof-$(CONFIG_SND_SOC_SOF_DEBUG_PROBES) += probe.o
 
 snd-sof-pci-objs := sof-pci-dev.o
 snd-sof-acpi-objs := sof-acpi-dev.o

sound/soc/sof/intel/hda-ipc.c

@@ -106,7 +106,9 @@ void hda_dsp_ipc_get_reply(struct snd_sof_dev *sdev)
 		ret = reply.error;
 	} else {
 		/* reply correct size ? */
-		if (reply.hdr.size != msg->reply_size) {
+		if (reply.hdr.size != msg->reply_size &&
+			/* getter payload is never known upfront */
+			!(reply.hdr.cmd & SOF_IPC_GLB_PROBE)) {
 			dev_err(sdev->dev, "error: reply expected %zu got %u bytes\n",
 				msg->reply_size, reply.hdr.size);
 			ret = -EINVAL;

sound/soc/sof/probe.c

@@ -0,0 +1,286 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+//
+// This file is provided under a dual BSD/GPLv2 license.  When using or
+// redistributing this file, you may do so under either license.
+//
+// Copyright(c) 2019-2020 Intel Corporation. All rights reserved.
+//
+// Author: Cezary Rojewski <cezary.rojewski@intel.com>
+//
+
+#include "sof-priv.h"
+#include "probe.h"
+
+/**
+ * sof_ipc_probe_init - initialize data probing
+ * @sdev:		SOF sound device
+ * @stream_tag:		Extractor stream tag
+ * @buffer_size:	DMA buffer size to set for extractor
+ *
+ * Host chooses whether extraction is supported or not by providing
+ * valid stream tag to DSP. Once specified, stream described by that
+ * tag will be tied to DSP for extraction for the entire lifetime of
+ * probe.
+ *
+ * Probing is initialized only once and each INIT request must be
+ * matched by DEINIT call.
+ */
+int sof_ipc_probe_init(struct snd_sof_dev *sdev,
+		u32 stream_tag, size_t buffer_size)
+{
+	struct sof_ipc_probe_dma_add_params *msg;
+	struct sof_ipc_reply reply;
+	size_t size = struct_size(msg, dma, 1);
+	int ret;
+
+	msg = kmalloc(size, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+	msg->hdr.size = size;
+	msg->hdr.cmd = SOF_IPC_GLB_PROBE | SOF_IPC_PROBE_INIT;
+	msg->num_elems = 1;
+	msg->dma[0].stream_tag = stream_tag;
+	msg->dma[0].dma_buffer_size = buffer_size;
+
+	ret = sof_ipc_tx_message(sdev->ipc, msg->hdr.cmd, msg, msg->hdr.size,
+			&reply, sizeof(reply));
+	kfree(msg);
+	return ret;
+}
+EXPORT_SYMBOL(sof_ipc_probe_init);
+
+/**
+ * sof_ipc_probe_deinit - cleanup after data probing
+ * @sdev:	SOF sound device
+ *
+ * Host sends DEINIT request to free previously initialized probe
+ * on DSP side once it is no longer needed. DEINIT only when there
+ * are no probes connected and with all injectors detached.
+ */
+int sof_ipc_probe_deinit(struct snd_sof_dev *sdev)
+{
+	struct sof_ipc_cmd_hdr msg;
+	struct sof_ipc_reply reply;
+
+	msg.size = sizeof(msg);
+	msg.cmd = SOF_IPC_GLB_PROBE | SOF_IPC_PROBE_DEINIT;
+
+	return sof_ipc_tx_message(sdev->ipc, msg.cmd, &msg, msg.size,
+			&reply, sizeof(reply));
+}
+EXPORT_SYMBOL(sof_ipc_probe_deinit);
+
+static int sof_ipc_probe_info(struct snd_sof_dev *sdev, unsigned int cmd,
+		void **params, size_t *num_params)
+{
+	struct sof_ipc_probe_info_params msg = {{{0}}};
+	struct sof_ipc_probe_info_params *reply;
+	size_t bytes;
+	int ret;
+
+	*params = NULL;
+	*num_params = 0;
+
+	reply = kzalloc(SOF_IPC_MSG_MAX_SIZE, GFP_KERNEL);
+	if (!reply)
+		return -ENOMEM;
+	msg.rhdr.hdr.size = sizeof(msg);
+	msg.rhdr.hdr.cmd = SOF_IPC_GLB_PROBE | cmd;
+
+	ret = sof_ipc_tx_message(sdev->ipc, msg.rhdr.hdr.cmd, &msg,
+			msg.rhdr.hdr.size, reply, SOF_IPC_MSG_MAX_SIZE);
+	if (ret < 0 || reply->rhdr.error < 0)
+		goto exit;
+
+	if (!reply->num_elems)
+		goto exit;
+
+	bytes = reply->num_elems * sizeof(reply->dma[0]);
+	*params = kmemdup(&reply->dma[0], bytes, GFP_KERNEL);
+	if (!*params) {
+		ret = -ENOMEM;
+		goto exit;
+	}
+	*num_params = msg.num_elems;
+
+exit:
+	kfree(reply);
+	return ret;
+}
+
+/**
+ * sof_ipc_probe_dma_info - retrieve list of active injection dmas
+ * @sdev:	SOF sound device
+ * @dma:	Returned list of active dmas
+ * @num_dma:	Returned count of active dmas
+ *
+ * Host sends DMA_INFO request to obtain list of injection dmas it
+ * can use to transfer data over with.
+ *
+ * Note that list contains only injection dmas as there is only one
+ * extractor (dma) and it is always assigned on probing init.
+ * DSP knows exactly where data from extraction probes is going to,
+ * which is not the case for injection where multiple streams
+ * could be engaged.
+ */
+int sof_ipc_probe_dma_info(struct snd_sof_dev *sdev,
+		struct sof_probe_dma **dma, size_t *num_dma)
+{
+	return sof_ipc_probe_info(sdev, SOF_IPC_PROBE_DMA_INFO,
+			(void **)dma, num_dma);
+}
+EXPORT_SYMBOL(sof_ipc_probe_dma_info);
+
+/**
+ * sof_ipc_probe_dma_add - attach to specified dmas
+ * @sdev:	SOF sound device
+ * @dma:	List of streams (dmas) to attach to
+ * @num_dma:	Number of elements in @dma
+ *
+ * Contrary to extraction, injection streams are never assigned
+ * on init. Before attempting any data injection, host is responsible
+ * for specifying streams which will be later used to transfer data
+ * to connected probe points.
+ */
+int sof_ipc_probe_dma_add(struct snd_sof_dev *sdev,
+		struct sof_probe_dma *dma, size_t num_dma)
+{
+	struct sof_ipc_probe_dma_add_params *msg;
+	struct sof_ipc_reply reply;
+	size_t size = struct_size(msg, dma, num_dma);
+	int ret;
+
+	msg = kmalloc(size, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+	msg->hdr.size = size;
+	msg->num_elems = num_dma;
+	msg->hdr.cmd = SOF_IPC_GLB_PROBE | SOF_IPC_PROBE_DMA_ADD;
+	memcpy(&msg->dma[0], dma, size - sizeof(*msg));
+
+	ret = sof_ipc_tx_message(sdev->ipc, msg->hdr.cmd, msg, msg->hdr.size,
+			&reply, sizeof(reply));
+	kfree(msg);
+	return ret;
+}
+EXPORT_SYMBOL(sof_ipc_probe_dma_add);
+
+/**
+ * sof_ipc_probe_dma_remove - detach from specified dmas
+ * @sdev:		SOF sound device
+ * @stream_tag:		List of stream tags to detach from
+ * @num_stream_tag:	Number of elements in @stream_tag
+ *
+ * Host sends DMA_REMOVE request to free previously attached stream
+ * from being occupied for injection. Each detach operation should
+ * match equivalent DMA_ADD. Detach only when all probes tied to
+ * given stream have been disconnected.
+ */
+int sof_ipc_probe_dma_remove(struct snd_sof_dev *sdev,
+		unsigned int *stream_tag, size_t num_stream_tag)
+{
+	struct sof_ipc_probe_dma_remove_params *msg;
+	struct sof_ipc_reply reply;
+	size_t size = struct_size(msg, stream_tag, num_stream_tag);
+	int ret;
+
+	msg = kmalloc(size, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+	msg->hdr.size = size;
+	msg->num_elems = num_stream_tag;
+	msg->hdr.cmd = SOF_IPC_GLB_PROBE | SOF_IPC_PROBE_DMA_REMOVE;
+	memcpy(&msg->stream_tag[0], stream_tag, size - sizeof(*msg));
+
+	ret = sof_ipc_tx_message(sdev->ipc, msg->hdr.cmd, msg, msg->hdr.size,
+			&reply, sizeof(reply));
+	kfree(msg);
+	return ret;
+}
+EXPORT_SYMBOL(sof_ipc_probe_dma_remove);
+
+/**
+ * sof_ipc_probe_points_info - retrieve list of active probe points
+ * @sdev:	SOF sound device
+ * @desc:	Returned list of active probes
+ * @num_desc:	Returned count of active probes
+ *
+ * Host sends PROBE_POINT_INFO request to obtain list of active probe
+ * points, valid for disconnection when given probe is no longer
+ * required.
+ */
+int sof_ipc_probe_points_info(struct snd_sof_dev *sdev,
+		struct sof_probe_point_desc **desc, size_t *num_desc)
+{
+	return sof_ipc_probe_info(sdev, SOF_IPC_PROBE_POINT_INFO,
+				 (void **)desc, num_desc);
+}
+EXPORT_SYMBOL(sof_ipc_probe_points_info);
+
+/**
+ * sof_ipc_probe_points_add - connect specified probes
+ * @sdev:	SOF sound device
+ * @desc:	List of probe points to connect
+ * @num_desc:	Number of elements in @desc
+ *
+ * Dynamically connects to provided set of endpoints. Immediately
+ * after connection is established, host must be prepared to
+ * transfer data from or to target stream given the probing purpose.
+ *
+ * Each probe point should be removed using PROBE_POINT_REMOVE
+ * request when no longer needed.
+ */
+int sof_ipc_probe_points_add(struct snd_sof_dev *sdev,
+		struct sof_probe_point_desc *desc, size_t num_desc)
+{
+	struct sof_ipc_probe_point_add_params *msg;
+	struct sof_ipc_reply reply;
+	size_t size = struct_size(msg, desc, num_desc);
+	int ret;
+
+	msg = kmalloc(size, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+	msg->hdr.size = size;
+	msg->num_elems = num_desc;
+	msg->hdr.cmd = SOF_IPC_GLB_PROBE | SOF_IPC_PROBE_POINT_ADD;
+	memcpy(&msg->desc[0], desc, size - sizeof(*msg));
+
+	ret = sof_ipc_tx_message(sdev->ipc, msg->hdr.cmd, msg, msg->hdr.size,
+			&reply, sizeof(reply));
+	kfree(msg);
+	return ret;
+}
+EXPORT_SYMBOL(sof_ipc_probe_points_add);
+
+/**
+ * sof_ipc_probe_points_remove - disconnect specified probes
+ * @sdev:		SOF sound device
+ * @buffer_id:		List of probe points to disconnect
+ * @num_buffer_id:	Number of elements in @desc
+ *
+ * Removes previously connected probes from list of active probe
+ * points and frees all resources on DSP side.
+ */
+int sof_ipc_probe_points_remove(struct snd_sof_dev *sdev,
+		unsigned int *buffer_id, size_t num_buffer_id)
+{
+	struct sof_ipc_probe_point_remove_params *msg;
+	struct sof_ipc_reply reply;
+	size_t size = struct_size(msg, buffer_id, num_buffer_id);
+	int ret;
+
+	msg = kmalloc(size, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+	msg->hdr.size = size;
+	msg->num_elems = num_buffer_id;
+	msg->hdr.cmd = SOF_IPC_GLB_PROBE | SOF_IPC_PROBE_POINT_REMOVE;
+	memcpy(&msg->buffer_id[0], buffer_id, size - sizeof(*msg));
+
+	ret = sof_ipc_tx_message(sdev->ipc, msg->hdr.cmd, msg, msg->hdr.size,
+			&reply, sizeof(reply));
+	kfree(msg);
+	return ret;
+}
+EXPORT_SYMBOL(sof_ipc_probe_points_remove);