3 #include <linux/wait.h>
4 #include <linux/ptrace.h>
7 #include <asm/spu_priv1.h>
9 #include <asm/unistd.h>
13 /* interrupt-level stop callback function. */
14 void spufs_stop_callback(struct spu *spu, int irq)
16 struct spu_context *ctx = spu->ctx;
19 * It should be impossible to preempt a context while an exception
20 * is being processed, since the context switch code is specially
21 * coded to deal with interrupts ... But, just in case, sanity check
22 * the context pointer. It is OK to return doing nothing since
23 * the exception will be regenerated when the context is resumed.
26 /* Copy exception arguments into module specific structure */
29 ctx->csa.class_0_pending = spu->class_0_pending;
30 ctx->csa.class_0_dar = spu->class_0_dar;
33 ctx->csa.class_1_dsisr = spu->class_1_dsisr;
34 ctx->csa.class_1_dar = spu->class_1_dar;
40 /* ensure that the exception status has hit memory before a
41 * thread waiting on the context's stop queue is woken */
44 wake_up_all(&ctx->stop_wq);
48 int spu_stopped(struct spu_context *ctx, u32 *stat)
53 stopped = SPU_STATUS_INVALID_INSTR | SPU_STATUS_SINGLE_STEP |
54 SPU_STATUS_STOPPED_BY_HALT | SPU_STATUS_STOPPED_BY_STOP;
57 *stat = ctx->ops->status_read(ctx);
58 if (*stat & stopped) {
60 * If the spu hasn't finished stopping, we need to
61 * re-read the register to get the stopped value.
63 if (*stat & SPU_STATUS_RUNNING)
68 if (test_bit(SPU_SCHED_NOTIFY_ACTIVE, &ctx->sched_flags))
71 dsisr = ctx->csa.class_1_dsisr;
72 if (dsisr & (MFC_DSISR_PTE_NOT_FOUND | MFC_DSISR_ACCESS_DENIED))
75 if (ctx->csa.class_0_pending)
81 static int spu_setup_isolated(struct spu_context *ctx)
84 u64 __iomem *mfc_cntl;
87 unsigned long timeout;
88 const u32 status_loading = SPU_STATUS_RUNNING
89 | SPU_STATUS_ISOLATED_STATE | SPU_STATUS_ISOLATED_LOAD_STATUS;
96 * We need to exclude userspace access to the context.
98 * To protect against memory access we invalidate all ptes
99 * and make sure the pagefault handlers block on the mutex.
101 spu_unmap_mappings(ctx);
103 mfc_cntl = &ctx->spu->priv2->mfc_control_RW;
105 /* purge the MFC DMA queue to ensure no spurious accesses before we
106 * enter kernel mode */
107 timeout = jiffies + HZ;
108 out_be64(mfc_cntl, MFC_CNTL_PURGE_DMA_REQUEST);
109 while ((in_be64(mfc_cntl) & MFC_CNTL_PURGE_DMA_STATUS_MASK)
110 != MFC_CNTL_PURGE_DMA_COMPLETE) {
111 if (time_after(jiffies, timeout)) {
112 printk(KERN_ERR "%s: timeout flushing MFC DMA queue\n",
120 /* put the SPE in kernel mode to allow access to the loader */
121 sr1 = spu_mfc_sr1_get(ctx->spu);
122 sr1 &= ~MFC_STATE1_PROBLEM_STATE_MASK;
123 spu_mfc_sr1_set(ctx->spu, sr1);
125 /* start the loader */
126 ctx->ops->signal1_write(ctx, (unsigned long)isolated_loader >> 32);
127 ctx->ops->signal2_write(ctx,
128 (unsigned long)isolated_loader & 0xffffffff);
130 ctx->ops->runcntl_write(ctx,
131 SPU_RUNCNTL_RUNNABLE | SPU_RUNCNTL_ISOLATE);
134 timeout = jiffies + HZ;
135 while (((status = ctx->ops->status_read(ctx)) & status_loading) ==
137 if (time_after(jiffies, timeout)) {
138 printk(KERN_ERR "%s: timeout waiting for loader\n",
146 if (!(status & SPU_STATUS_RUNNING)) {
147 /* If isolated LOAD has failed: run SPU, we will get a stop-and
149 pr_debug("%s: isolated LOAD failed\n", __func__);
150 ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE);
155 if (!(status & SPU_STATUS_ISOLATED_STATE)) {
156 /* This isn't allowed by the CBEA, but check anyway */
157 pr_debug("%s: SPU fell out of isolated mode?\n", __func__);
158 ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_STOP);
164 /* Finished accessing the loader. Drop kernel mode */
165 sr1 |= MFC_STATE1_PROBLEM_STATE_MASK;
166 spu_mfc_sr1_set(ctx->spu, sr1);
172 static int spu_run_init(struct spu_context *ctx, u32 *npc)
174 unsigned long runcntl = SPU_RUNCNTL_RUNNABLE;
177 spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);
180 * NOSCHED is synchronous scheduling with respect to the caller.
181 * The caller waits for the context to be loaded.
183 if (ctx->flags & SPU_CREATE_NOSCHED) {
184 if (ctx->state == SPU_STATE_SAVED) {
185 ret = spu_activate(ctx, 0);
192 * Apply special setup as required.
194 if (ctx->flags & SPU_CREATE_ISOLATE) {
195 if (!(ctx->ops->status_read(ctx) & SPU_STATUS_ISOLATED_STATE)) {
196 ret = spu_setup_isolated(ctx);
202 * If userspace has set the runcntrl register (eg, to
203 * issue an isolated exit), we need to re-set it here
205 runcntl = ctx->ops->runcntl_read(ctx) &
206 (SPU_RUNCNTL_RUNNABLE | SPU_RUNCNTL_ISOLATE);
208 runcntl = SPU_RUNCNTL_RUNNABLE;
210 unsigned long privcntl;
212 if (test_thread_flag(TIF_SINGLESTEP))
213 privcntl = SPU_PRIVCNTL_MODE_SINGLE_STEP;
215 privcntl = SPU_PRIVCNTL_MODE_NORMAL;
217 ctx->ops->privcntl_write(ctx, privcntl);
218 ctx->ops->npc_write(ctx, *npc);
221 ctx->ops->runcntl_write(ctx, runcntl);
223 if (ctx->flags & SPU_CREATE_NOSCHED) {
224 spuctx_switch_state(ctx, SPU_UTIL_USER);
227 if (ctx->state == SPU_STATE_SAVED) {
228 ret = spu_activate(ctx, 0);
232 spuctx_switch_state(ctx, SPU_UTIL_USER);
236 set_bit(SPU_SCHED_SPU_RUN, &ctx->sched_flags);
240 static int spu_run_fini(struct spu_context *ctx, u32 *npc,
245 spu_del_from_rq(ctx);
247 *status = ctx->ops->status_read(ctx);
248 *npc = ctx->ops->npc_read(ctx);
250 spuctx_switch_state(ctx, SPU_UTIL_IDLE_LOADED);
251 clear_bit(SPU_SCHED_SPU_RUN, &ctx->sched_flags);
252 spu_switch_log_notify(NULL, ctx, SWITCH_LOG_EXIT, *status);
255 if (signal_pending(current))
262 * SPU syscall restarting is tricky because we violate the basic
263 * assumption that the signal handler is running on the interrupted
264 * thread. Here instead, the handler runs on PowerPC user space code,
265 * while the syscall was called from the SPU.
266 * This means we can only do a very rough approximation of POSIX
269 static int spu_handle_restartsys(struct spu_context *ctx, long *spu_ret,
276 case -ERESTARTNOINTR:
278 * Enter the regular syscall restarting for
279 * sys_spu_run, then restart the SPU syscall
285 case -ERESTARTNOHAND:
286 case -ERESTART_RESTARTBLOCK:
288 * Restart block is too hard for now, just return -EINTR
290 * ERESTARTNOHAND comes from sys_pause, we also return
292 * Assume that we need to be restarted ourselves though.
298 printk(KERN_WARNING "%s: unexpected return code %ld\n",
305 static int spu_process_callback(struct spu_context *ctx)
307 struct spu_syscall_block s;
313 /* get syscall block from local store */
314 npc = ctx->ops->npc_read(ctx) & ~3;
315 ls = (void __iomem *)ctx->ops->get_ls(ctx);
316 ls_pointer = in_be32(ls + npc);
317 if (ls_pointer > (LS_SIZE - sizeof(s)))
319 memcpy_fromio(&s, ls + ls_pointer, sizeof(s));
321 /* do actual syscall without pinning the spu */
326 if (s.nr_ret < __NR_syscalls) {
328 /* do actual system call from here */
329 spu_ret = spu_sys_callback(&s);
330 if (spu_ret <= -ERESTARTSYS) {
331 ret = spu_handle_restartsys(ctx, &spu_ret, &npc);
333 mutex_lock(&ctx->state_mutex);
334 if (ret == -ERESTARTSYS)
338 /* need to re-get the ls, as it may have changed when we released the
340 ls = (void __iomem *)ctx->ops->get_ls(ctx);
342 /* write result, jump over indirect pointer */
343 memcpy_toio(ls + ls_pointer, &spu_ret, sizeof(spu_ret));
344 ctx->ops->npc_write(ctx, npc);
345 ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE);
349 long spufs_run_spu(struct spu_context *ctx, u32 *npc, u32 *event)
355 if (mutex_lock_interruptible(&ctx->run_mutex))
358 ctx->event_return = 0;
360 ret = spu_acquire(ctx);
366 spu_update_sched_info(ctx);
368 ret = spu_run_init(ctx, npc);
375 ret = spufs_wait(ctx->stop_wq, spu_stopped(ctx, &status));
378 * This is nasty: we need the state_mutex for all the
379 * bookkeeping even if the syscall was interrupted by
382 mutex_lock(&ctx->state_mutex);
386 if (unlikely(test_and_clear_bit(SPU_SCHED_NOTIFY_ACTIVE,
387 &ctx->sched_flags))) {
388 if (!(status & SPU_STATUS_STOPPED_BY_STOP)) {
389 spu_switch_notify(spu, ctx);
394 spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);
396 if ((status & SPU_STATUS_STOPPED_BY_STOP) &&
397 (status >> SPU_STOP_STATUS_SHIFT == 0x2104)) {
398 ret = spu_process_callback(ctx);
401 status &= ~SPU_STATUS_STOPPED_BY_STOP;
403 ret = spufs_handle_class1(ctx);
407 ret = spufs_handle_class0(ctx);
411 if (signal_pending(current))
413 } while (!ret && !(status & (SPU_STATUS_STOPPED_BY_STOP |
414 SPU_STATUS_STOPPED_BY_HALT |
415 SPU_STATUS_SINGLE_STEP)));
417 spu_disable_spu(ctx);
418 ret = spu_run_fini(ctx, npc, &status);
421 if ((status & SPU_STATUS_STOPPED_BY_STOP) &&
422 (((status >> SPU_STOP_STATUS_SHIFT) & 0x3f00) == 0x2100))
423 ctx->stats.libassist++;
426 ((ret == -ERESTARTSYS) &&
427 ((status & SPU_STATUS_STOPPED_BY_HALT) ||
428 (status & SPU_STATUS_SINGLE_STEP) ||
429 ((status & SPU_STATUS_STOPPED_BY_STOP) &&
430 (status >> SPU_STOP_STATUS_SHIFT != 0x2104)))))
433 /* Note: we don't need to force_sig SIGTRAP on single-step
434 * since we have TIF_SINGLESTEP set, thus the kernel will do
435 * it upon return from the syscall anyawy
437 if (unlikely(status & SPU_STATUS_SINGLE_STEP))
440 else if (unlikely((status & SPU_STATUS_STOPPED_BY_STOP)
441 && (status >> SPU_STOP_STATUS_SHIFT) == 0x3fff)) {
442 force_sig(SIGTRAP, current);
447 *event = ctx->event_return;
449 mutex_unlock(&ctx->run_mutex);