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/mutex.h>
27 #include <linux/spinlock.h>
28 #include <linux/fs.h>
29 #include <linux/cpumask.h>
30 #include <linux/sched/signal.h>
31 
32 #include <asm/spu.h>
33 #include <asm/spu_csa.h>
34 #include <asm/spu_info.h>
35 
36 #define SPUFS_PS_MAP_SIZE	0x20000
37 #define SPUFS_MFC_MAP_SIZE	0x1000
38 #define SPUFS_CNTL_MAP_SIZE	0x1000
39 #define SPUFS_SIGNAL_MAP_SIZE	PAGE_SIZE
40 #define SPUFS_MSS_MAP_SIZE	0x1000
41 
42 /* The magic number for our file system */
43 enum {
44 	SPUFS_MAGIC = 0x23c9b64e,
45 };
46 
47 struct spu_context_ops;
48 struct spu_gang;
49 
50 /* ctx->sched_flags */
51 enum {
52 	SPU_SCHED_NOTIFY_ACTIVE,
53 	SPU_SCHED_WAS_ACTIVE,	/* was active upon spu_acquire_saved()  */
54 	SPU_SCHED_SPU_RUN,	/* context is within spu_run */
55 };
56 
57 enum {
58 	SWITCH_LOG_BUFSIZE = 4096,
59 };
60 
61 enum {
62 	SWITCH_LOG_START,
63 	SWITCH_LOG_STOP,
64 	SWITCH_LOG_EXIT,
65 };
66 
67 struct switch_log {
68 	wait_queue_head_t	wait;
69 	unsigned long		head;
70 	unsigned long		tail;
71 	struct switch_log_entry {
72 		struct timespec64 tstamp;
73 		s32		spu_id;
74 		u32		type;
75 		u32		val;
76 		u64		timebase;
77 	} log[];
78 };
79 
80 struct spu_context {
81 	struct spu *spu;		  /* pointer to a physical SPU */
82 	struct spu_state csa;		  /* SPU context save area. */
83 	spinlock_t mmio_lock;		  /* protects mmio access */
84 	struct address_space *local_store; /* local store mapping.  */
85 	struct address_space *mfc;	   /* 'mfc' area mappings. */
86 	struct address_space *cntl;	   /* 'control' area mappings. */
87 	struct address_space *signal1;	   /* 'signal1' area mappings. */
88 	struct address_space *signal2;	   /* 'signal2' area mappings. */
89 	struct address_space *mss;	   /* 'mss' area mappings. */
90 	struct address_space *psmap;	   /* 'psmap' area mappings. */
91 	struct mutex mapping_lock;
92 	u64 object_id;		   /* user space pointer for oprofile */
93 
94 	enum { SPU_STATE_RUNNABLE, SPU_STATE_SAVED } state;
95 	struct mutex state_mutex;
96 	struct mutex run_mutex;
97 
98 	struct mm_struct *owner;
99 
100 	struct kref kref;
101 	wait_queue_head_t ibox_wq;
102 	wait_queue_head_t wbox_wq;
103 	wait_queue_head_t stop_wq;
104 	wait_queue_head_t mfc_wq;
105 	wait_queue_head_t run_wq;
106 	u32 tagwait;
107 	struct spu_context_ops *ops;
108 	struct work_struct reap_work;
109 	unsigned long flags;
110 	unsigned long event_return;
111 
112 	struct list_head gang_list;
113 	struct spu_gang *gang;
114 	struct kref *prof_priv_kref;
115 	void ( * prof_priv_release) (struct kref *kref);
116 
117 	/* owner thread */
118 	pid_t tid;
119 
120 	/* scheduler fields */
121 	struct list_head rq;
122 	unsigned int time_slice;
123 	unsigned long sched_flags;
124 	cpumask_t cpus_allowed;
125 	int policy;
126 	int prio;
127 	int last_ran;
128 
129 	/* statistics */
130 	struct {
131 		/* updates protected by ctx->state_mutex */
132 		enum spu_utilization_state util_state;
133 		unsigned long long tstamp;	/* time of last state switch */
134 		unsigned long long times[SPU_UTIL_MAX];
135 		unsigned long long vol_ctx_switch;
136 		unsigned long long invol_ctx_switch;
137 		unsigned long long min_flt;
138 		unsigned long long maj_flt;
139 		unsigned long long hash_flt;
140 		unsigned long long slb_flt;
141 		unsigned long long slb_flt_base; /* # at last ctx switch */
142 		unsigned long long class2_intr;
143 		unsigned long long class2_intr_base; /* # at last ctx switch */
144 		unsigned long long libassist;
145 	} stats;
146 
147 	/* context switch log */
148 	struct switch_log *switch_log;
149 
150 	struct list_head aff_list;
151 	int aff_head;
152 	int aff_offset;
153 };
154 
155 struct spu_gang {
156 	struct list_head list;
157 	struct mutex mutex;
158 	struct kref kref;
159 	int contexts;
160 
161 	struct spu_context *aff_ref_ctx;
162 	struct list_head aff_list_head;
163 	struct mutex aff_mutex;
164 	int aff_flags;
165 	struct spu *aff_ref_spu;
166 	atomic_t aff_sched_count;
167 };
168 
169 /* Flag bits for spu_gang aff_flags */
170 #define AFF_OFFSETS_SET		1
171 #define AFF_MERGED		2
172 
173 struct mfc_dma_command {
174 	int32_t pad;	/* reserved */
175 	uint32_t lsa;	/* local storage address */
176 	uint64_t ea;	/* effective address */
177 	uint16_t size;	/* transfer size */
178 	uint16_t tag;	/* command tag */
179 	uint16_t class;	/* class ID */
180 	uint16_t cmd;	/* command opcode */
181 };
182 
183 
184 /* SPU context query/set operations. */
185 struct spu_context_ops {
186 	int (*mbox_read) (struct spu_context * ctx, u32 * data);
187 	 u32(*mbox_stat_read) (struct spu_context * ctx);
188 	__poll_t (*mbox_stat_poll)(struct spu_context *ctx, __poll_t events);
189 	int (*ibox_read) (struct spu_context * ctx, u32 * data);
190 	int (*wbox_write) (struct spu_context * ctx, u32 data);
191 	 u32(*signal1_read) (struct spu_context * ctx);
192 	void (*signal1_write) (struct spu_context * ctx, u32 data);
193 	 u32(*signal2_read) (struct spu_context * ctx);
194 	void (*signal2_write) (struct spu_context * ctx, u32 data);
195 	void (*signal1_type_set) (struct spu_context * ctx, u64 val);
196 	 u64(*signal1_type_get) (struct spu_context * ctx);
197 	void (*signal2_type_set) (struct spu_context * ctx, u64 val);
198 	 u64(*signal2_type_get) (struct spu_context * ctx);
199 	 u32(*npc_read) (struct spu_context * ctx);
200 	void (*npc_write) (struct spu_context * ctx, u32 data);
201 	 u32(*status_read) (struct spu_context * ctx);
202 	char*(*get_ls) (struct spu_context * ctx);
203 	void (*privcntl_write) (struct spu_context *ctx, u64 data);
204 	 u32 (*runcntl_read) (struct spu_context * ctx);
205 	void (*runcntl_write) (struct spu_context * ctx, u32 data);
206 	void (*runcntl_stop) (struct spu_context * ctx);
207 	void (*master_start) (struct spu_context * ctx);
208 	void (*master_stop) (struct spu_context * ctx);
209 	int (*set_mfc_query)(struct spu_context * ctx, u32 mask, u32 mode);
210 	u32 (*read_mfc_tagstatus)(struct spu_context * ctx);
211 	u32 (*get_mfc_free_elements)(struct spu_context *ctx);
212 	int (*send_mfc_command)(struct spu_context * ctx,
213 				struct mfc_dma_command * cmd);
214 	void (*dma_info_read) (struct spu_context * ctx,
215 			       struct spu_dma_info * info);
216 	void (*proxydma_info_read) (struct spu_context * ctx,
217 				    struct spu_proxydma_info * info);
218 	void (*restart_dma)(struct spu_context *ctx);
219 };
220 
221 extern struct spu_context_ops spu_hw_ops;
222 extern struct spu_context_ops spu_backing_ops;
223 
224 struct spufs_inode_info {
225 	struct spu_context *i_ctx;
226 	struct spu_gang *i_gang;
227 	struct inode vfs_inode;
228 	int i_openers;
229 };
230 #define SPUFS_I(inode) \
231 	container_of(inode, struct spufs_inode_info, vfs_inode)
232 
233 struct spufs_tree_descr {
234 	const char *name;
235 	const struct file_operations *ops;
236 	umode_t mode;
237 	size_t size;
238 };
239 
240 extern const struct spufs_tree_descr spufs_dir_contents[];
241 extern const struct spufs_tree_descr spufs_dir_nosched_contents[];
242 extern const struct spufs_tree_descr spufs_dir_debug_contents[];
243 
244 /* system call implementation */
245 extern struct spufs_calls spufs_calls;
246 struct coredump_params;
247 long spufs_run_spu(struct spu_context *ctx, u32 *npc, u32 *status);
248 long spufs_create(struct path *nd, struct dentry *dentry, unsigned int flags,
249 			umode_t mode, struct file *filp);
250 /* ELF coredump callbacks for writing SPU ELF notes */
251 extern int spufs_coredump_extra_notes_size(void);
252 extern int spufs_coredump_extra_notes_write(struct coredump_params *cprm);
253 
254 extern const struct file_operations spufs_context_fops;
255 
256 /* gang management */
257 struct spu_gang *alloc_spu_gang(void);
258 struct spu_gang *get_spu_gang(struct spu_gang *gang);
259 int put_spu_gang(struct spu_gang *gang);
260 void spu_gang_remove_ctx(struct spu_gang *gang, struct spu_context *ctx);
261 void spu_gang_add_ctx(struct spu_gang *gang, struct spu_context *ctx);
262 
263 /* fault handling */
264 int spufs_handle_class1(struct spu_context *ctx);
265 int spufs_handle_class0(struct spu_context *ctx);
266 
267 /* affinity */
268 struct spu *affinity_check(struct spu_context *ctx);
269 
270 /* context management */
271 extern atomic_t nr_spu_contexts;
272 static inline int __must_check spu_acquire(struct spu_context *ctx)
273 {
274 	return mutex_lock_interruptible(&ctx->state_mutex);
275 }
276 
277 static inline void spu_release(struct spu_context *ctx)
278 {
279 	mutex_unlock(&ctx->state_mutex);
280 }
281 
282 struct spu_context * alloc_spu_context(struct spu_gang *gang);
283 void destroy_spu_context(struct kref *kref);
284 struct spu_context * get_spu_context(struct spu_context *ctx);
285 int put_spu_context(struct spu_context *ctx);
286 void spu_unmap_mappings(struct spu_context *ctx);
287 
288 void spu_forget(struct spu_context *ctx);
289 int __must_check spu_acquire_saved(struct spu_context *ctx);
290 void spu_release_saved(struct spu_context *ctx);
291 
292 int spu_stopped(struct spu_context *ctx, u32 * stat);
293 void spu_del_from_rq(struct spu_context *ctx);
294 int spu_activate(struct spu_context *ctx, unsigned long flags);
295 void spu_deactivate(struct spu_context *ctx);
296 void spu_yield(struct spu_context *ctx);
297 void spu_switch_notify(struct spu *spu, struct spu_context *ctx);
298 void spu_switch_log_notify(struct spu *spu, struct spu_context *ctx,
299 		u32 type, u32 val);
300 void spu_set_timeslice(struct spu_context *ctx);
301 void spu_update_sched_info(struct spu_context *ctx);
302 void __spu_update_sched_info(struct spu_context *ctx);
303 int __init spu_sched_init(void);
304 void spu_sched_exit(void);
305 
306 extern char *isolated_loader;
307 
308 /*
309  * spufs_wait
310  *	Same as wait_event_interruptible(), except that here
311  *	we need to call spu_release(ctx) before sleeping, and
312  *	then spu_acquire(ctx) when awoken.
313  *
314  * 	Returns with state_mutex re-acquired when successful or
315  * 	with -ERESTARTSYS and the state_mutex dropped when interrupted.
316  */
317 
318 #define spufs_wait(wq, condition)					\
319 ({									\
320 	int __ret = 0;							\
321 	DEFINE_WAIT(__wait);						\
322 	for (;;) {							\
323 		prepare_to_wait(&(wq), &__wait, TASK_INTERRUPTIBLE);	\
324 		if (condition)						\
325 			break;						\
326 		spu_release(ctx);					\
327 		if (signal_pending(current)) {				\
328 			__ret = -ERESTARTSYS;				\
329 			break;						\
330 		}							\
331 		schedule();						\
332 		__ret = spu_acquire(ctx);				\
333 		if (__ret)						\
334 			break;						\
335 	}								\
336 	finish_wait(&(wq), &__wait);					\
337 	__ret;								\
338 })
339 
340 size_t spu_wbox_write(struct spu_context *ctx, u32 data);
341 size_t spu_ibox_read(struct spu_context *ctx, u32 *data);
342 
343 /* irq callback funcs. */
344 void spufs_ibox_callback(struct spu *spu);
345 void spufs_wbox_callback(struct spu *spu);
346 void spufs_stop_callback(struct spu *spu, int irq);
347 void spufs_mfc_callback(struct spu *spu);
348 void spufs_dma_callback(struct spu *spu, int type);
349 
350 extern struct spu_coredump_calls spufs_coredump_calls;
351 struct spufs_coredump_reader {
352 	char *name;
353 	ssize_t (*read)(struct spu_context *ctx,
354 			char __user *buffer, size_t size, loff_t *pos);
355 	u64 (*get)(struct spu_context *ctx);
356 	size_t size;
357 };
358 extern const struct spufs_coredump_reader spufs_coredump_read[];
359 extern int spufs_coredump_num_notes;
360 
361 extern int spu_init_csa(struct spu_state *csa);
362 extern void spu_fini_csa(struct spu_state *csa);
363 extern int spu_save(struct spu_state *prev, struct spu *spu);
364 extern int spu_restore(struct spu_state *new, struct spu *spu);
365 extern int spu_switch(struct spu_state *prev, struct spu_state *new,
366 		      struct spu *spu);
367 extern int spu_alloc_lscsa(struct spu_state *csa);
368 extern void spu_free_lscsa(struct spu_state *csa);
369 
370 extern void spuctx_switch_state(struct spu_context *ctx,
371 		enum spu_utilization_state new_state);
372 
373 #endif
374