1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Tegra host1x Command DMA
4  *
5  * Copyright (c) 2010-2013, NVIDIA Corporation.
6  */
7 
8 #ifndef __HOST1X_CDMA_H
9 #define __HOST1X_CDMA_H
10 
11 #include <linux/sched.h>
12 #include <linux/completion.h>
13 #include <linux/list.h>
14 
15 struct host1x_syncpt;
16 struct host1x_userctx_timeout;
17 struct host1x_job;
18 
19 /*
20  * cdma
21  *
22  * This is in charge of a host command DMA channel.
23  * Sends ops to a push buffer, and takes responsibility for unpinning
24  * (& possibly freeing) of memory after those ops have completed.
25  * Producer:
26  *	begin
27  *		push - send ops to the push buffer
28  *	end - start command DMA and enqueue handles to be unpinned
29  * Consumer:
30  *	update - call to update sync queue and push buffer, unpin memory
31  */
32 
33 struct push_buffer {
34 	void *mapped;			/* mapped pushbuffer memory */
35 	dma_addr_t dma;			/* device address of pushbuffer */
36 	dma_addr_t phys;		/* physical address of pushbuffer */
37 	u32 fence;			/* index we've written */
38 	u32 pos;			/* index to write to */
39 	u32 size;
40 	u32 alloc_size;
41 };
42 
43 struct buffer_timeout {
44 	struct delayed_work wq;		/* work queue */
45 	bool initialized;		/* timer one-time setup flag */
46 	struct host1x_syncpt *syncpt;	/* buffer completion syncpt */
47 	u32 syncpt_val;			/* syncpt value when completed */
48 	ktime_t start_ktime;		/* starting time */
49 	/* context timeout information */
50 	struct host1x_client *client;
51 };
52 
53 enum cdma_event {
54 	CDMA_EVENT_NONE,		/* not waiting for any event */
55 	CDMA_EVENT_SYNC_QUEUE_EMPTY,	/* wait for empty sync queue */
56 	CDMA_EVENT_PUSH_BUFFER_SPACE	/* wait for space in push buffer */
57 };
58 
59 struct host1x_cdma {
60 	struct mutex lock;		/* controls access to shared state */
61 	struct completion complete;	/* signalled when event occurs */
62 	enum cdma_event event;		/* event that complete is waiting for */
63 	unsigned int slots_used;	/* pb slots used in current submit */
64 	unsigned int slots_free;	/* pb slots free in current submit */
65 	unsigned int first_get;		/* DMAGET value, where submit begins */
66 	unsigned int last_pos;		/* last value written to DMAPUT */
67 	struct push_buffer push_buffer;	/* channel's push buffer */
68 	struct list_head sync_queue;	/* job queue */
69 	struct buffer_timeout timeout;	/* channel's timeout state/wq */
70 	bool running;
71 	bool torndown;
72 };
73 
74 #define cdma_to_channel(cdma) container_of(cdma, struct host1x_channel, cdma)
75 #define cdma_to_host1x(cdma) dev_get_drvdata(cdma_to_channel(cdma)->dev->parent)
76 #define pb_to_cdma(pb) container_of(pb, struct host1x_cdma, push_buffer)
77 
78 int host1x_cdma_init(struct host1x_cdma *cdma);
79 int host1x_cdma_deinit(struct host1x_cdma *cdma);
80 int host1x_cdma_begin(struct host1x_cdma *cdma, struct host1x_job *job);
81 void host1x_cdma_push(struct host1x_cdma *cdma, u32 op1, u32 op2);
82 void host1x_cdma_push_wide(struct host1x_cdma *cdma, u32 op1, u32 op2,
83 			   u32 op3, u32 op4);
84 void host1x_cdma_end(struct host1x_cdma *cdma, struct host1x_job *job);
85 void host1x_cdma_update(struct host1x_cdma *cdma);
86 void host1x_cdma_peek(struct host1x_cdma *cdma, u32 dmaget, int slot,
87 		      u32 *out);
88 unsigned int host1x_cdma_wait_locked(struct host1x_cdma *cdma,
89 				     enum cdma_event event);
90 void host1x_cdma_update_sync_queue(struct host1x_cdma *cdma,
91 				   struct device *dev);
92 #endif
93