path: root/drivers/misc/fastrpc.c

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2011-2018, The Linux Foundation. All rights reserved.
// Copyright (c) 2018, Linaro Limited

#include <linux/completion.h>
#include <linux/device.h>
#include <linux/dma-buf.h>
#include <linux/dma-mapping.h>
#include <linux/idr.h>
#include <linux/list.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of.h>
#include <linux/sort.h>
#include <linux/of_platform.h>
#include <linux/rpmsg.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <uapi/misc/fastrpc.h>

#define ADSP_DOMAIN_ID (0)
#define MDSP_DOMAIN_ID (1)
#define SDSP_DOMAIN_ID (2)
#define CDSP_DOMAIN_ID (3)
#define FASTRPC_DEV_MAX		4 /* adsp, mdsp, slpi, cdsp*/
#define FASTRPC_MAX_SESSIONS	9 /*8 compute, 1 cpz*/
#define FASTRPC_ALIGN		128
#define FASTRPC_MAX_FDLIST	16
#define FASTRPC_MAX_CRCLIST	64
#define FASTRPC_PHYS(p)	((p) & 0xffffffff)
#define FASTRPC_CTX_MAX (256)
#define FASTRPC_INIT_HANDLE	1
#define FASTRPC_CTXID_MASK (0xFF0)
#define INIT_FILELEN_MAX (64 * 1024 * 1024)
#define FASTRPC_DEVICE_NAME	"fastrpc"

/* Retrives number of input buffers from the scalars parameter */
#define REMOTE_SCALARS_INBUFS(sc)	(((sc) >> 16) & 0x0ff)

/* Retrives number of output buffers from the scalars parameter */
#define REMOTE_SCALARS_OUTBUFS(sc)	(((sc) >> 8) & 0x0ff)

/* Retrives number of input handles from the scalars parameter */
#define REMOTE_SCALARS_INHANDLES(sc)	(((sc) >> 4) & 0x0f)

/* Retrives number of output handles from the scalars parameter */
#define REMOTE_SCALARS_OUTHANDLES(sc)	((sc) & 0x0f)

#define REMOTE_SCALARS_LENGTH(sc)	(REMOTE_SCALARS_INBUFS(sc) +   \
					 REMOTE_SCALARS_OUTBUFS(sc) +  \
					 REMOTE_SCALARS_INHANDLES(sc)+ \
					 REMOTE_SCALARS_OUTHANDLES(sc))
#define FASTRPC_BUILD_SCALARS(attr, method, in, out, oin, oout)  \
				(((attr & 0x07) << 29) |		\
				((method & 0x1f) << 24) |	\
				((in & 0xff) << 16) |		\
				((out & 0xff) <<  8) |		\
				((oin & 0x0f) <<  4) |		\
				(oout & 0x0f))

#define FASTRPC_SCALARS(method, in, out) \
		FASTRPC_BUILD_SCALARS(0, method, in, out, 0, 0)

#define FASTRPC_CREATE_PROCESS_NARGS	6
/* Remote Method id table */
#define FASTRPC_RMID_INIT_ATTACH	0
#define FASTRPC_RMID_INIT_RELEASE	1
#define FASTRPC_RMID_INIT_CREATE	6
#define FASTRPC_RMID_INIT_CREATE_ATTR	7
#define FASTRPC_RMID_INIT_CREATE_STATIC	8

#define miscdev_to_cctx(d) container_of(d, struct fastrpc_channel_ctx, miscdev)

static const char *domains[FASTRPC_DEV_MAX] = { "adsp", "mdsp",
						"sdsp", "cdsp"};
struct fastrpc_phy_page {
	u64 addr;		/* physical address */
	u64 size;		/* size of contiguous region */
};

struct fastrpc_invoke_buf {
	u32 num;		/* number of contiguous regions */
	u32 pgidx;		/* index to start of contiguous region */
};

struct fastrpc_remote_arg {
	u64 pv;
	u64 len;
};

struct fastrpc_msg {
	int pid;		/* process group id */
	int tid;		/* thread id */
	u64 ctx;		/* invoke caller context */
	u32 handle;	/* handle to invoke */
	u32 sc;		/* scalars structure describing the data */
	u64 addr;		/* physical address */
	u64 size;		/* size of contiguous region */
};

struct fastrpc_invoke_rsp {
	u64 ctx;		/* invoke caller context */
	int retval;		/* invoke return value */
};

struct fastrpc_buf_overlap {
	u64 start;
	u64 end;
	int raix;
	u64 mstart;
	u64 mend;
	u64 offset;
};

struct fastrpc_buf {
	struct fastrpc_user *fl;
	struct dma_buf *dmabuf;
	struct device *dev;
	void *virt;
	u64 phys;
	u64 size;
	/* Lock for dma buf attachments */
	struct mutex lock;
	struct list_head attachments;
};

struct fastrpc_dma_buf_attachment {
	struct device *dev;
	struct sg_table sgt;
	struct list_head node;
};

struct fastrpc_map {
	struct list_head node;
	struct fastrpc_user *fl;
	int fd;
	struct dma_buf *buf;
	struct sg_table *table;
	struct dma_buf_attachment *attach;
	u64 phys;
	u64 size;
	void *va;
	u64 len;
	struct kref refcount;
};

struct fastrpc_invoke_ctx {
	int nscalars;
	int nbufs;
	int retval;
	int pid;
	int tgid;
	u32 sc;
	u32 *crc;
	u64 ctxid;
	u64 msg_sz;
	struct kref refcount;
	struct list_head node; /* list of ctxs */
	struct completion work;
	struct work_struct put_work;
	struct fastrpc_msg msg;
	struct fastrpc_user *fl;
	struct fastrpc_remote_arg *rpra;
	struct fastrpc_map **maps;
	struct fastrpc_buf *buf;
	struct fastrpc_invoke_args *args;
	struct fastrpc_buf_overlap *olaps;
	struct fastrpc_channel_ctx *cctx;
};

struct fastrpc_session_ctx {
	struct device *dev;
	int sid;
	bool used;
	bool valid;
};

struct fastrpc_channel_ctx {
	int domain_id;
	int sesscount;
	struct rpmsg_device *rpdev;
	struct fastrpc_session_ctx session[FASTRPC_MAX_SESSIONS];
	spinlock_t lock;
	struct idr ctx_idr;
	struct list_head users;
	struct miscdevice miscdev;
	struct kref refcount;
};

struct fastrpc_user {
	struct list_head user;
	struct list_head maps;
	struct list_head pending;

	struct fastrpc_channel_ctx *cctx;
	struct fastrpc_session_ctx *sctx;
	struct fastrpc_buf *init_mem;

	int tgid;
	int pd;
	/* Lock for lists */
	spinlock_t lock;
	/* lock for allocations */
	struct mutex mutex;
};

static void fastrpc_free_map(struct kref *ref)
{
	struct fastrpc_map *map;

	map = container_of(ref, struct fastrpc_map, refcount);

	if (map->table) {
		dma_buf_unmap_attachment(map->attach, map->table,
					 DMA_BIDIRECTIONAL);
		dma_buf_detach(map->buf, map->attach);
		dma_buf_put(map->buf);
	}

	if (map->fl) {
		spin_lock(&map->fl->lock);
		list_del(&map->node);
		spin_unlock(&map->fl->lock);
		map->fl = NULL;
	}

	kfree(map);