1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * SPU file system
4  *
5  * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
6  *
7  * Author: Arnd Bergmann <arndb@de.ibm.com>
8  */
9 #ifndef SPUFS_H
10 #define SPUFS_H
11 
12 #include <linux/kref.h>
13 #include <linux/mutex.h>
14 #include <linux/spinlock.h>
15 #include <linux/fs.h>
16 #include <linux/cpumask.h>
17 #include <linux/sched/signal.h>
18 
19 #include <asm/spu.h>
20 #include <asm/spu_csa.h>
21 #include <asm/spu_info.h>
22 
23 #define SPUFS_PS_MAP_SIZE	0x20000
24 #define SPUFS_MFC_MAP_SIZE	0x1000
25 #define SPUFS_CNTL_MAP_SIZE	0x1000
26 #define SPUFS_SIGNAL_MAP_SIZE	PAGE_SIZE
27 #define SPUFS_MSS_MAP_SIZE	0x1000
28 
29 /* The magic number for our file system */
30 enum {
31 	SPUFS_MAGIC = 0x23c9b64e,
32 };
33 
34 struct spu_context_ops;
35 struct spu_gang;
36 
37 /* ctx->sched_flags */
38 enum {
39 	SPU_SCHED_NOTIFY_ACTIVE,
40 	SPU_SCHED_WAS_ACTIVE,	/* was active upon spu_acquire_saved()  */
41 	SPU_SCHED_SPU_RUN,	/* context is within spu_run */
42 };
43 
44 enum {
45 	SWITCH_LOG_BUFSIZE = 4096,
46 };
47 
48 enum {
49 	SWITCH_LOG_START,
50 	SWITCH_LOG_STOP,
51 	SWITCH_LOG_EXIT,
52 };
53 
54 struct switch_log {
55 	wait_queue_head_t	wait;
56 	unsigned long		head;
57 	unsigned long		tail;
58 	struct switch_log_entry {
59 		struct timespec64 tstamp;
60 		s32		spu_id;
61 		u32		type;
62 		u32		val;
63 		u64		timebase;
64 	} log[];
65 };
66 
67 struct spu_context {
68 	struct spu *spu;		  /* pointer to a physical SPU */
69 	struct spu_state csa;		  /* SPU context save area. */
70 	spinlock_t mmio_lock;		  /* protects mmio access */
71 	struct address_space *local_store; /* local store mapping.  */
72 	struct address_space *mfc;	   /* 'mfc' area mappings. */
73 	struct address_space *cntl;	   /* 'control' area mappings. */
74 	struct address_space *signal1;	   /* 'signal1' area mappings. */
75 	struct address_space *signal2;	   /* 'signal2' area mappings. */
76 	struct address_space *mss;	   /* 'mss' area mappings. */
77 	struct address_space *psmap;	   /* 'psmap' area mappings. */
78 	struct mutex mapping_lock;
79 	u64 object_id;		   /* user space pointer for oprofile */
80 
81 	enum { SPU_STATE_RUNNABLE, SPU_STATE_SAVED } state;
82 	struct mutex state_mutex;
83 	struct mutex run_mutex;
84 
85 	struct mm_struct *owner;
86 
87 	struct kref kref;
88 	wait_queue_head_t ibox_wq;
89 	wait_queue_head_t wbox_wq;
90 	wait_queue_head_t stop_wq;
91 	wait_queue_head_t mfc_wq;
92 	wait_queue_head_t run_wq;
93 	u32 tagwait;
94 	struct spu_context_ops *ops;
95 	struct work_struct reap_work;
96 	unsigned long flags;
97 	unsigned long event_return;
98 
99 	struct list_head gang_list;
100 	struct spu_gang *gang;
101 	struct kref *prof_priv_kref;
102 	void ( * prof_priv_release) (struct kref *kref);
103 
104 	/* owner thread */
105 	pid_t tid;
106 
107 	/* scheduler fields */
108 	struct list_head rq;
109 	unsigned int time_slice;
110 	unsigned long sched_flags;
111 	cpumask_t cpus_allowed;
112 	int policy;
113 	int prio;
114 	int last_ran;
115 
116 	/* statistics */
117 	struct {
118 		/* updates protected by ctx->state_mutex */
119 		enum spu_utilization_state util_state;
120 		unsigned long long tstamp;	/* time of last state switch */
121 		unsigned long long times[SPU_UTIL_MAX];
122 		unsigned long long vol_ctx_switch;
123 		unsigned long long invol_ctx_switch;
124 		unsigned long long min_flt;
125 		unsigned long long maj_flt;
126 		unsigned long long hash_flt;
127 		unsigned long long slb_flt;
128 		unsigned long long slb_flt_base; /* # at last ctx switch */
129 		unsigned long long class2_intr;
130 		unsigned long long class2_intr_base; /* # at last ctx switch */
131 		unsigned long long libassist;
132 	} stats;
133 
134 	/* context switch log */
135 	struct switch_log *switch_log;
136 
137 	struct list_head aff_list;
138 	int aff_head;
139 	int aff_offset;
140 };
141 
142 struct spu_gang {
143 	struct list_head list;
144 	struct mutex mutex;
145 	struct kref kref;
146 	int contexts;
147 
148 	struct spu_context *aff_ref_ctx;
149 	struct list_head aff_list_head;
150 	struct mutex aff_mutex;
151 	int aff_flags;
152 	struct spu *aff_ref_spu;
153 	atomic_t aff_sched_count;
154 };
155 
156 /* Flag bits for spu_gang aff_flags */
157 #define AFF_OFFSETS_SET		1
158 #define AFF_MERGED		2
159 
160 struct mfc_dma_command {
161 	int32_t pad;	/* reserved */
162 	uint32_t lsa;	/* local storage address */
163 	uint64_t ea;	/* effective address */
164 	uint16_t size;	/* transfer size */
165 	uint16_t tag;	/* command tag */
166 	uint16_t class;	/* class ID */
167 	uint16_t cmd;	/* command opcode */
168 };
169 
170 
171 /* SPU context query/set operations. */
172 struct spu_context_ops {
173 	int (*mbox_read) (struct spu_context * ctx, u32 * data);
174 	 u32(*mbox_stat_read) (struct spu_context * ctx);
175 	__poll_t (*mbox_stat_poll)(struct spu_context *ctx, __poll_t events);
176 	int (*ibox_read) (struct spu_context * ctx, u32 * data);
177 	int (*wbox_write) (struct spu_context * ctx, u32 data);
178 	 u32(*signal1_read) (struct spu_context * ctx);
179 	void (*signal1_write) (struct spu_context * ctx, u32 data);
180 	 u32(*signal2_read) (struct spu_context * ctx);
181 	void (*signal2_write) (struct spu_context * ctx, u32 data);
182 	void (*signal1_type_set) (struct spu_context * ctx, u64 val);
183 	 u64(*signal1_type_get) (struct spu_context * ctx);
184 	void (*signal2_type_set) (struct spu_context * ctx, u64 val);
185 	 u64(*signal2_type_get) (struct spu_context * ctx);
186 	 u32(*npc_read) (struct spu_context * ctx);
187 	void (*npc_write) (struct spu_context * ctx, u32 data);
188 	 u32(*status_read) (struct spu_context * ctx);
189 	char*(*get_ls) (struct spu_context * ctx);
190 	void (*privcntl_write) (struct spu_context *ctx, u64 data);
191 	 u32 (*runcntl_read) (struct spu_context * ctx);
192 	void (*runcntl_write) (struct spu_context * ctx, u32 data);
193 	void (*runcntl_stop) (struct spu_context * ctx);
194 	void (*master_start) (struct spu_context * ctx);
195 	void (*master_stop) (struct spu_context * ctx);
196 	int (*set_mfc_query)(struct spu_context * ctx, u32 mask, u32 mode);
197 	u32 (*read_mfc_tagstatus)(struct spu_context * ctx);
198 	u32 (*get_mfc_free_elements)(struct spu_context *ctx);
199 	int (*send_mfc_command)(struct spu_context * ctx,
200 				struct mfc_dma_command * cmd);
201 	void (*dma_info_read) (struct spu_context * ctx,
202 			       struct spu_dma_info * info);
203 	void (*proxydma_info_read) (struct spu_context * ctx,
204 				    struct spu_proxydma_info * info);
205 	void (*restart_dma)(struct spu_context *ctx);
206 };
207 
208 extern struct spu_context_ops spu_hw_ops;
209 extern struct spu_context_ops spu_backing_ops;
210 
211 struct spufs_inode_info {
212 	struct spu_context *i_ctx;
213 	struct spu_gang *i_gang;
214 	struct inode vfs_inode;
215 	int i_openers;
216 };
217 #define SPUFS_I(inode) \
218 	container_of(inode, struct spufs_inode_info, vfs_inode)
219 
220 struct spufs_tree_descr {
221 	const char *name;
222 	const struct file_operations *ops;
223 	umode_t mode;
224 	size_t size;
225 };
226 
227 extern const struct spufs_tree_descr spufs_dir_contents[];
228 extern const struct spufs_tree_descr spufs_dir_nosched_contents[];
229 extern const struct spufs_tree_descr spufs_dir_debug_contents[];
230 
231 /* system call implementation */
232 extern struct spufs_calls spufs_calls;
233 struct coredump_params;
234 long spufs_run_spu(struct spu_context *ctx, u32 *npc, u32 *status);
235 long spufs_create(struct path *nd, struct dentry *dentry, unsigned int flags,
236 			umode_t mode, struct file *filp);
237 /* ELF coredump callbacks for writing SPU ELF notes */
238 extern int spufs_coredump_extra_notes_size(void);
239 extern int spufs_coredump_extra_notes_write(struct coredump_params *cprm);
240 
241 extern const struct file_operations spufs_context_fops;
242 
243 /* gang management */
244 struct spu_gang *alloc_spu_gang(void);
245 struct spu_gang *get_spu_gang(struct spu_gang *gang);
246 int put_spu_gang(struct spu_gang *gang);
247 void spu_gang_remove_ctx(struct spu_gang *gang, struct spu_context *ctx);
248 void spu_gang_add_ctx(struct spu_gang *gang, struct spu_context *ctx);
249 
250 /* fault handling */
251 int spufs_handle_class1(struct spu_context *ctx);
252 int spufs_handle_class0(struct spu_context *ctx);
253 
254 /* affinity */
255 struct spu *affinity_check(struct spu_context *ctx);
256 
257 /* context management */
258 extern atomic_t nr_spu_contexts;
259 static inline int __must_check spu_acquire(struct spu_context *ctx)
260 {
261 	return mutex_lock_interruptible(&ctx->state_mutex);
262 }
263 
264 static inline void spu_release(struct spu_context *ctx)
265 {
266 	mutex_unlock(&ctx->state_mutex);
267 }
268 
269 struct spu_context * alloc_spu_context(struct spu_gang *gang);
270 void destroy_spu_context(struct kref *kref);
271 struct spu_context * get_spu_context(struct spu_context *ctx);
272 int put_spu_context(struct spu_context *ctx);
273 void spu_unmap_mappings(struct spu_context *ctx);
274 
275 void spu_forget(struct spu_context *ctx);
276 int __must_check spu_acquire_saved(struct spu_context *ctx);
277 void spu_release_saved(struct spu_context *ctx);
278 
279 int spu_stopped(struct spu_context *ctx, u32 * stat);
280 void spu_del_from_rq(struct spu_context *ctx);
281 int spu_activate(struct spu_context *ctx, unsigned long flags);
282 void spu_deactivate(struct spu_context *ctx);
283 void spu_yield(struct spu_context *ctx);
284 void spu_switch_log_notify(struct spu *spu, struct spu_context *ctx,
285 		u32 type, u32 val);
286 void spu_set_timeslice(struct spu_context *ctx);
287 void spu_update_sched_info(struct spu_context *ctx);
288 void __spu_update_sched_info(struct spu_context *ctx);
289 int __init spu_sched_init(void);
290 void spu_sched_exit(void);
291 
292 extern char *isolated_loader;
293 
294 /*
295  * spufs_wait
296  *	Same as wait_event_interruptible(), except that here
297  *	we need to call spu_release(ctx) before sleeping, and
298  *	then spu_acquire(ctx) when awoken.
299  *
300  * 	Returns with state_mutex re-acquired when successful or
301  * 	with -ERESTARTSYS and the state_mutex dropped when interrupted.
302  */
303 
304 #define spufs_wait(wq, condition)					\
305 ({									\
306 	int __ret = 0;							\
307 	DEFINE_WAIT(__wait);						\
308 	for (;;) {							\
309 		prepare_to_wait(&(wq), &__wait, TASK_INTERRUPTIBLE);	\
310 		if (condition)						\
311 			break;						\
312 		spu_release(ctx);					\
313 		if (signal_pending(current)) {				\
314 			__ret = -ERESTARTSYS;				\
315 			break;						\
316 		}							\
317 		schedule();						\
318 		__ret = spu_acquire(ctx);				\
319 		if (__ret)						\
320 			break;						\
321 	}								\
322 	finish_wait(&(wq), &__wait);					\
323 	__ret;								\
324 })
325 
326 size_t spu_wbox_write(struct spu_context *ctx, u32 data);
327 size_t spu_ibox_read(struct spu_context *ctx, u32 *data);
328 
329 /* irq callback funcs. */
330 void spufs_ibox_callback(struct spu *spu);
331 void spufs_wbox_callback(struct spu *spu);
332 void spufs_stop_callback(struct spu *spu, int irq);
333 void spufs_mfc_callback(struct spu *spu);
334 void spufs_dma_callback(struct spu *spu, int type);
335 
336 extern struct spu_coredump_calls spufs_coredump_calls;
337 struct spufs_coredump_reader {
338 	char *name;
339 	ssize_t (*dump)(struct spu_context *ctx, struct coredump_params *cprm);
340 	u64 (*get)(struct spu_context *ctx);
341 	size_t size;
342 };
343 extern const struct spufs_coredump_reader spufs_coredump_read[];
344 extern int spufs_coredump_num_notes;
345 
346 extern int spu_init_csa(struct spu_state *csa);
347 extern void spu_fini_csa(struct spu_state *csa);
348 extern int spu_save(struct spu_state *prev, struct spu *spu);
349 extern int spu_restore(struct spu_state *new, struct spu *spu);
350 extern int spu_switch(struct spu_state *prev, struct spu_state *new,
351 		      struct spu *spu);
352 extern int spu_alloc_lscsa(struct spu_state *csa);
353 extern void spu_free_lscsa(struct spu_state *csa);
354 
355 extern void spuctx_switch_state(struct spu_context *ctx,
356 		enum spu_utilization_state new_state);
357 
358 #endif
359