MLK-18497-4: ASoC: fsl: dsp: Add message buffer pool API

Memory is allocated to clients from memory pools. A memory pool
allocation is requested to DSP framework via XF_ALLOC command and
freed via XF_FREE.

Memory pool allocation API offers two functions:
	* xf_pool_alloc, allocate a number of buffers of given length
	* xf_pool_free, free memory area allocated for a pool.

Once a buffer pool is allocated users can handle buffers using the
following API:
	* xf_buffer_get(pool), gets a buffer from a pool
	* xf_buffer_put(buf), puts back a buffer into its pool

Reviewed-by: Cosmin-Gabriel Samoila <cosmin.samoila@nxp.com>
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>

sound/soc/fsl/Makefile

@@ -15,7 +15,7 @@ obj-$(CONFIG_SND_SOC_P1022_RDK) += snd-soc-p1022-rdk.o
 snd-soc-fsl-audmix-objs := fsl_audmix.o
 snd-soc-fsl-asoc-card-objs := fsl-asoc-card.o
 snd-soc-fsl-asrc-objs := fsl_asrc.o fsl_asrc_dma.o
-snd-soc-fsl-dsp-objs := fsl_dsp.o fsl_dsp_proxy.o
+snd-soc-fsl-dsp-objs := fsl_dsp.o fsl_dsp_proxy.o fsl_dsp_pool.o
 snd-soc-fsl-sai-objs := fsl_sai.o
 snd-soc-fsl-ssi-y := fsl_ssi.o
 snd-soc-fsl-ssi-$(CONFIG_DEBUG_FS) += fsl_ssi_dbg.o

sound/soc/fsl/fsl_dsp.h

@@ -37,6 +37,9 @@ struct xf_client {
 	/* ...global structure pointer */
 	void	*global;
 	struct xf_message m;
+
+	struct work_struct work;
+	struct completion compr_complete;
 };
 
 union xf_client_link {

sound/soc/fsl/fsl_dsp_pool.c

@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Xtensa buffer pool API
+//
+// Copyright 2018 NXP
+// Copyright (c) 2012-2013 by Tensilica Inc.
+
+#include <linux/slab.h>
+
+#include "fsl_dsp_pool.h"
+#include "fsl_dsp.h"
+
+/* ...allocate buffer pool */
+int xf_pool_alloc(struct xf_client *client, struct xf_proxy *proxy,
+		  u32 number, u32 length, xf_pool_type_t type,
+		  struct xf_pool **pool)
+{
+	struct xf_pool      *p;
+	struct xf_buffer    *b;
+	void  *data;
+	struct xf_message    msg;
+	struct xf_message   *rmsg;
+
+	/* ...basic sanity checks; number of buffers is positive */
+	if (number <=0)
+		return -EINVAL;
+
+	/* ...get properly aligned buffer length */
+	length = ALIGN(length, XF_PROXY_ALIGNMENT);
+
+	p = kzalloc(offsetof(struct xf_pool, buffer) +
+		    number * sizeof(struct xf_buffer), GFP_KERNEL);
+	if(!p)
+		return -ENOMEM;
+
+	/* ...prepare command parameters */
+	msg.id = __XF_MSG_ID(__XF_AP_PROXY(0), __XF_DSP_PROXY(0));
+	msg.id = XF_MSG_AP_FROM_USER(msg.id, client->id);
+	msg.opcode = XF_ALLOC;
+	msg.length = length * number;
+	msg.buffer = NULL;
+	msg.ret = 0;
+
+	/* ...execute command synchronously */
+	rmsg = xf_cmd_send_recv_complete(client, proxy, msg.id, msg.opcode,
+					 msg.buffer, msg.length, &client->work,
+					 &client->compr_complete);
+	if (IS_ERR(rmsg)) {
+		kfree(p);
+		return PTR_ERR(rmsg);
+	}
+
+	p->p = rmsg->buffer;
+	/* TODO: review cleanup */
+	/* xf_msg_free(proxy, rmsg);
+	 * xf_unlock(&proxy->lock); */
+
+	/* ...if operation is failed, do cleanup */
+	/* ...set pool parameters */
+	p->number = number, p->length = length;
+	p->proxy = proxy;
+
+	/* ...create individual buffers and link them into free list */
+	for (p->free = b = &p->buffer[0], data = p->p; number > 0;
+			number--, b++) {
+		/* ...set address of the buffer (no length there) */
+		b->address = data;
+
+		/* ...file buffer into the free list */
+		b->link.next = b + 1;
+
+		/* ...advance data pointer in contiguous buffer */
+		data += length;
+	}
+
+	/* ...terminate list of buffers (not too good - tbd) */
+	b[-1].link.next = NULL;
+
+	/* ...return buffer pointer */
+	*pool = p;
+
+	return 0;
+}
+/* ...buffer pool destruction */
+int xf_pool_free(struct xf_client *client, struct xf_pool *pool)
+{
+	struct xf_proxy     *proxy;
+	struct xf_message    msg;
+	struct xf_message   *rmsg;
+
+	/* ...basic sanity checks; pool is positive */
+	if (pool == NULL)
+		return -EINVAL;
+
+	/* ...get proxy pointer */
+	if ((proxy = pool->proxy) == NULL)
+		return -EINVAL;
+
+	/* ...prepare command parameters */
+	msg.id = __XF_MSG_ID(__XF_AP_PROXY(0), __XF_DSP_PROXY(0));
+	msg.id = XF_MSG_AP_FROM_USER(msg.id, client->id);
+	msg.opcode = XF_FREE;
+	msg.length = pool->length * pool->number;
+	msg.buffer = pool->p;
+	msg.ret = 0;
+
+	/* ...execute command synchronously */
+	rmsg = xf_cmd_send_recv_complete(client, proxy, msg.id, msg.opcode,
+					 msg.buffer, msg.length, &client->work,
+					 &client->compr_complete);
+	kfree(pool);
+	if (IS_ERR(rmsg))
+		return PTR_ERR(rmsg);
+
+	/* TODO: review cleanup */
+	/* xf_msg_free(proxy, rmsg);
+	 * xf_unlock(&proxy->lock); */
+
+	return 0;
+}
+
+/* ...get new buffer from a pool */
+struct xf_buffer *xf_buffer_get(struct xf_pool *pool)
+{
+	struct xf_buffer    *b;
+
+	xf_lock(&pool->proxy->lock);
+	/* ...take buffer from a head of the free list */
+	b = pool->free;
+	if (b) {
+		/* ...advance free list head */
+		pool->free = b->link.next, b->link.pool = pool;
+	}
+
+	xf_unlock(&pool->proxy->lock);
+	return b;
+}
+
+/* ...return buffer back to pool */
+void xf_buffer_put(struct xf_buffer *buffer)
+{
+	struct xf_pool  *pool = buffer->link.pool;
+
+	xf_lock(&pool->proxy->lock);
+	/* ...use global proxy lock for pool operations protection */
+	/* ...put buffer back to a pool */
+	buffer->link.next = pool->free, pool->free = buffer;
+
+	xf_unlock(&pool->proxy->lock);
+}

sound/soc/fsl/fsl_dsp_pool.h

@@ -0,0 +1,113 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Xtensa buffer pool API header
+ *
+ * Copyright 2018 NXP
+ * Copyright (c) 2012-2013 by Tensilica Inc
+ */
+#ifndef FSL_DSP_POOL_H
+#define FSL_DSP_POOL_H
+
+#include <linux/types.h>
+#include "fsl_dsp_proxy.h"
+
+/* ...buffer pool type */
+typedef u32 xf_pool_type_t;
+
+/* ...previous declaration of struct */
+struct xf_buffer;
+struct xf_pool;
+struct xf_handle;
+struct xf_message;
+struct xf_client;
+
+/* ...response callback */
+typedef void (*xf_response_cb)(struct xf_handle *h, struct xf_message *msg);
+
+/* ...buffer pool type */
+enum xf_pool_type {
+        XF_POOL_AUX = 0,
+        XF_POOL_INPUT = 1,
+        XF_POOL_OUTPUT = 2
+};
+
+/* ...buffer link pointer */
+union xf_buffer_link {
+        /* ...pointer to next free buffer in a pool (for free buffer) */
+        struct xf_buffer *next;
+        /* ...reference to a buffer pool (for allocated buffer) */
+        struct xf_pool *pool;
+};
+
+/* ...buffer descriptor */
+struct xf_buffer {
+        /* ...virtual address of contiguous buffer */
+        void *address;
+        /* ...link pointer */
+        union xf_buffer_link link;
+};
+
+/* ...buffer pool */
+struct xf_pool {
+        /* ...reference to proxy data */
+        struct xf_proxy *proxy;
+        /* ...length of individual buffer in a pool */
+        u32 length;
+        /* ...number of buffers in a pool */
+        u32 number;
+        /* ...pointer to pool memory */
+        void *p;
+        /* ...pointer to first free buffer in a pool */
+        struct xf_buffer *free;
+        /* ...individual buffers */
+        struct xf_buffer buffer[0];
+};
+
+/* component handle */
+struct xf_handle {
+        /* ...reference to proxy data */
+        struct xf_proxy *proxy;
+        /* ...auxiliary control buffer for control transactions */
+        struct xf_buffer *aux;
+        /* ...global client-id of the component */
+        u32 id;
+        /* ...local client number (think about merging into "id" field - tbd) */
+        u32 client;
+        /* ...response processing hook */
+        xf_response_cb response;
+};
+
+/* ...accessor to buffer data */
+static inline void *xf_buffer_data(struct xf_buffer *buffer)
+{
+        return buffer->address;
+}
+
+/* ...length of buffer data */
+static inline size_t xf_buffer_length(struct xf_buffer *buffer)
+{
+        struct xf_pool *pool = buffer->link.pool;
+
+        return (size_t)pool->length;
+}
+
+/* ...component client-id (global scope) */
+static inline u32 xf_handle_id(struct xf_handle *handle)
+{
+        return handle->id;
+}
+
+/* ...pointer to auxiliary buffer */
+static inline void *xf_handle_aux(struct xf_handle *handle)
+{
+        return xf_buffer_data(handle->aux);
+}
+
+int xf_pool_alloc(struct xf_client *client, struct xf_proxy *proxy, u32 number,
+		  u32 length, xf_pool_type_t type, struct xf_pool **pool);
+int xf_pool_free(struct xf_client *client, struct xf_pool *pool);
+
+struct xf_buffer *xf_buffer_get(struct xf_pool *pool);
+void xf_buffer_put(struct xf_buffer *buffer);
+
+#endif /* FSL_DSP_POOL_H */

sound/soc/fsl/fsl_dsp_proxy.h

@@ -309,6 +309,9 @@ struct xf_proxy {
 
 	/* ...pointer to first free message in the pool */
 	struct xf_message       *free;
+
+        /* ...auxiliary buffer pool for clients */
+	struct xf_pool          *aux;
 };
 
 union icm_header_t {