1 /*
2  * SPU file system
3  *
4  * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
5  *
6  * Author: Arnd Bergmann <arndb@de.ibm.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2, or (at your option)
11  * any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 #ifndef SPUFS_H
23 #define SPUFS_H
24 
25 #include <linux/kref.h>
26 #include <linux/rwsem.h>
27 #include <linux/spinlock.h>
28 #include <linux/fs.h>
29 
30 #include <asm/spu.h>
31 #include <asm/spu_csa.h>
32 
33 /* The magic number for our file system */
34 enum {
35 	SPUFS_MAGIC = 0x23c9b64e,
36 };
37 
38 struct spu_context_ops;
39 
40 #define SPU_CONTEXT_PREEMPT          0UL
41 
42 struct spu_context {
43 	struct spu *spu;		  /* pointer to a physical SPU */
44 	struct spu_state csa;		  /* SPU context save area. */
45 	spinlock_t mmio_lock;		  /* protects mmio access */
46 	struct address_space *local_store;/* local store backing store */
47 
48 	enum { SPU_STATE_RUNNABLE, SPU_STATE_SAVED } state;
49 	struct rw_semaphore state_sema;
50 	struct semaphore run_sema;
51 
52 	struct mm_struct *owner;
53 
54 	struct kref kref;
55 	wait_queue_head_t ibox_wq;
56 	wait_queue_head_t wbox_wq;
57 	wait_queue_head_t stop_wq;
58 	struct fasync_struct *ibox_fasync;
59 	struct fasync_struct *wbox_fasync;
60 	struct spu_context_ops *ops;
61 	struct work_struct reap_work;
62 	u64 flags;
63 };
64 
65 /* SPU context query/set operations. */
66 struct spu_context_ops {
67 	int (*mbox_read) (struct spu_context * ctx, u32 * data);
68 	 u32(*mbox_stat_read) (struct spu_context * ctx);
69 	unsigned int (*mbox_stat_poll)(struct spu_context *ctx,
70 					unsigned int events);
71 	int (*ibox_read) (struct spu_context * ctx, u32 * data);
72 	int (*wbox_write) (struct spu_context * ctx, u32 data);
73 	 u32(*signal1_read) (struct spu_context * ctx);
74 	void (*signal1_write) (struct spu_context * ctx, u32 data);
75 	 u32(*signal2_read) (struct spu_context * ctx);
76 	void (*signal2_write) (struct spu_context * ctx, u32 data);
77 	void (*signal1_type_set) (struct spu_context * ctx, u64 val);
78 	 u64(*signal1_type_get) (struct spu_context * ctx);
79 	void (*signal2_type_set) (struct spu_context * ctx, u64 val);
80 	 u64(*signal2_type_get) (struct spu_context * ctx);
81 	 u32(*npc_read) (struct spu_context * ctx);
82 	void (*npc_write) (struct spu_context * ctx, u32 data);
83 	 u32(*status_read) (struct spu_context * ctx);
84 	char*(*get_ls) (struct spu_context * ctx);
85 	void (*runcntl_write) (struct spu_context * ctx, u32 data);
86 	void (*runcntl_stop) (struct spu_context * ctx);
87 };
88 
89 extern struct spu_context_ops spu_hw_ops;
90 extern struct spu_context_ops spu_backing_ops;
91 
92 struct spufs_inode_info {
93 	struct spu_context *i_ctx;
94 	struct inode vfs_inode;
95 };
96 #define SPUFS_I(inode) \
97 	container_of(inode, struct spufs_inode_info, vfs_inode)
98 
99 extern struct tree_descr spufs_dir_contents[];
100 
101 /* system call implementation */
102 long spufs_run_spu(struct file *file,
103 		   struct spu_context *ctx, u32 *npc, u32 *status);
104 long spufs_create_thread(struct nameidata *nd,
105 			 unsigned int flags, mode_t mode);
106 extern struct file_operations spufs_context_fops;
107 
108 /* context management */
109 struct spu_context * alloc_spu_context(struct address_space *local_store);
110 void destroy_spu_context(struct kref *kref);
111 struct spu_context * get_spu_context(struct spu_context *ctx);
112 int put_spu_context(struct spu_context *ctx);
113 void spu_unmap_mappings(struct spu_context *ctx);
114 
115 void spu_forget(struct spu_context *ctx);
116 void spu_acquire(struct spu_context *ctx);
117 void spu_release(struct spu_context *ctx);
118 int spu_acquire_runnable(struct spu_context *ctx);
119 void spu_acquire_saved(struct spu_context *ctx);
120 
121 int spu_activate(struct spu_context *ctx, u64 flags);
122 void spu_deactivate(struct spu_context *ctx);
123 void spu_yield(struct spu_context *ctx);
124 int __init spu_sched_init(void);
125 void __exit spu_sched_exit(void);
126 
127 /*
128  * spufs_wait
129  * 	Same as wait_event_interruptible(), except that here
130  *	we need to call spu_release(ctx) before sleeping, and
131  *	then spu_acquire(ctx) when awoken.
132  */
133 
134 #define spufs_wait(wq, condition)					\
135 ({									\
136 	int __ret = 0;							\
137 	DEFINE_WAIT(__wait);						\
138 	for (;;) {							\
139 		prepare_to_wait(&(wq), &__wait, TASK_INTERRUPTIBLE);	\
140 		if (condition)						\
141 			break;						\
142 		if (!signal_pending(current)) {				\
143 			spu_release(ctx);				\
144 			schedule();					\
145 			spu_acquire(ctx);				\
146 			continue;					\
147 		}							\
148 		__ret = -ERESTARTSYS;					\
149 		break;							\
150 	}								\
151 	finish_wait(&(wq), &__wait);					\
152 	__ret;								\
153 })
154 
155 size_t spu_wbox_write(struct spu_context *ctx, u32 data);
156 size_t spu_ibox_read(struct spu_context *ctx, u32 *data);
157 
158 /* irq callback funcs. */
159 void spufs_ibox_callback(struct spu *spu);
160 void spufs_wbox_callback(struct spu *spu);
161 void spufs_stop_callback(struct spu *spu);
162 
163 #endif
164