[deliverable/linux.git] / arch / powerpc / platforms / cell / spufs / run.c

#define DEBUG

#include <linux/wait.h>
#include <linux/ptrace.h>

#include <asm/spu.h>
#include <asm/spu_priv1.h>
#include <asm/io.h>
#include <asm/unistd.h>

#include "spufs.h"

/* interrupt-level stop callback function. */
void spufs_stop_callback(struct spu *spu, int irq)
{
	struct spu_context *ctx = spu->ctx;

	/*
	 * It should be impossible to preempt a context while an exception
	 * is being processed, since the context switch code is specially
	 * coded to deal with interrupts ... But, just in case, sanity check
	 * the context pointer.  It is OK to return doing nothing since
	 * the exception will be regenerated when the context is resumed.
	 */
	if (ctx) {
		/* Copy exception arguments into module specific structure */
		switch(irq) {
		case 0 :
			ctx->csa.class_0_pending = spu->class_0_pending;
			ctx->csa.class_0_dar = spu->class_0_dar;
			break;
		case 1 :
			ctx->csa.class_1_dsisr = spu->class_1_dsisr;
			ctx->csa.class_1_dar = spu->class_1_dar;
			break;
		case 2 :
			break;
		}

		/* ensure that the exception status has hit memory before a
		 * thread waiting on the context's stop queue is woken */
		smp_wmb();

		wake_up_all(&ctx->stop_wq);
	}
}

int spu_stopped(struct spu_context *ctx, u32 *stat)
{
	u64 dsisr;
	u32 stopped;

	stopped = SPU_STATUS_INVALID_INSTR | SPU_STATUS_SINGLE_STEP |
		SPU_STATUS_STOPPED_BY_HALT | SPU_STATUS_STOPPED_BY_STOP;

top:
	*stat = ctx->ops->status_read(ctx);
	if (*stat & stopped) {
		/*
		 * If the spu hasn't finished stopping, we need to
		 * re-read the register to get the stopped value.
		 */
		if (*stat & SPU_STATUS_RUNNING)
			goto top;
		return 1;
	}

	if (test_bit(SPU_SCHED_NOTIFY_ACTIVE, &ctx->sched_flags))
		return 1;

	dsisr = ctx->csa.class_1_dsisr;
	if (dsisr & (MFC_DSISR_PTE_NOT_FOUND | MFC_DSISR_ACCESS_DENIED))
		return 1;

	if (ctx->csa.class_0_pending)
		return 1;

	return 0;
}

static int spu_setup_isolated(struct spu_context *ctx)
{
	int ret;
	u64 __iomem *mfc_cntl;
	u64 sr1;
	u32 status;
	unsigned long timeout;
	const u32 status_loading = SPU_STATUS_RUNNING
		| SPU_STATUS_ISOLATED_STATE | SPU_STATUS_ISOLATED_LOAD_STATUS;

	ret = -ENODEV;
	if (!isolated_loader)
		goto out;

	/*
	 * We need to exclude userspace access to the context.
	 *
	 * To protect against memory access we invalidate all ptes
	 * and make sure the pagefault handlers block on the mutex.
	 */
	spu_unmap_mappings(ctx);

	mfc_cntl = &ctx->spu->priv2->mfc_control_RW;

	/* purge the MFC DMA queue to ensure no spurious accesses before we
	 * enter kernel mode */
	timeout = jiffies + HZ;
	out_be64(mfc_cntl, MFC_CNTL_PURGE_DMA_REQUEST);
	while ((in_be64(mfc_cntl) & MFC_CNTL_PURGE_DMA_STATUS_MASK)
			!= MFC_CNTL_PURGE_DMA_COMPLETE) {
		if (time_after(jiffies, timeout)) {
			printk(KERN_ERR "%s: timeout flushing MFC DMA queue\n",
					__func__);
			ret = -EIO;
			goto out;
		}
		cond_resched();
	}

	/* put the SPE in kernel mode to allow access to the loader */
	sr1 = spu_mfc_sr1_get(ctx->spu);
	sr1 &= ~MFC_STATE1_PROBLEM_STATE_MASK;
	spu_mfc_sr1_set(ctx->spu, sr1);

	/* start the loader */
	ctx->ops->signal1_write(ctx, (unsigned long)isolated_loader >> 32);
	ctx->ops->signal2_write(ctx,
			(unsigned long)isolated_loader & 0xffffffff);

	ctx->ops->runcntl_write(ctx,
			SPU_RUNCNTL_RUNNABLE | SPU_RUNCNTL_ISOLATE);

	ret = 0;
	timeout = jiffies + HZ;
	while (((status = ctx->ops->status_read(ctx)) & status_loading) ==
				status_loading) {
		if (time_after(jiffies, timeout)) {
			printk(KERN_ERR "%s: timeout waiting for loader\n",
					__func__);
			ret = -EIO;
			goto out_drop_priv;
		}
		cond_resched();
	}

	if (!(status & SPU_STATUS_RUNNING)) {
		/* If isolated LOAD has failed: run SPU, we will get a stop-and
		 * signal later. */
		pr_debug("%s: isolated LOAD failed\n", __func__);
		ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE);
		ret = -EACCES;
		goto out_drop_priv;
	}

	if (!(status & SPU_STATUS_ISOLATED_STATE)) {
		/* This isn't allowed by the CBEA, but check anyway */
		pr_debug("%s: SPU fell out of isolated mode?\n", __func__);
		ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_STOP);
		ret = -EINVAL;
		goto out_drop_priv;
	}

out_drop_priv:
	/* Finished accessing the loader. Drop kernel mode */
	sr1 |= MFC_STATE1_PROBLEM_STATE_MASK;
	spu_mfc_sr1_set(ctx->spu, sr1);

out:
	return ret;
}

static int spu_run_init(struct spu_context *ctx, u32 *npc)
{
	unsigned long runcntl = SPU_RUNCNTL_RUNNABLE;
	int ret;

	spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);

	/*
	 * NOSCHED is synchronous scheduling with respect to the caller.
	 * The caller waits for the context to be loaded.
	 */
	if (ctx->flags & SPU_CREATE_NOSCHED) {
		if (ctx->state == SPU_STATE_SAVED) {
			ret = spu_activate(ctx, 0);
			if (ret)
				return ret;
		}
	}

	/*
	 * Apply special setup as required.
	 */
	if (ctx->flags & SPU_CREATE_ISOLATE) {
		if (!(ctx->ops->status_read(ctx) & SPU_STATUS_ISOLATED_STATE)) {
			ret = spu_setup_isolated(ctx);
			if (ret)
				return ret;
		}

		/*
		 * If userspace has set the runcntrl register (eg, to
		 * issue an isolated exit), we need to re-set it here
		 */
		runcntl = ctx->ops->runcntl_read(ctx) &
			(SPU_RUNCNTL_RUNNABLE | SPU_RUNCNTL_ISOLATE);
		if (runcntl == 0)
			runcntl = SPU_RUNCNTL_RUNNABLE;
	} else {
		unsigned long privcntl;

		if (test_thread_flag(TIF_SINGLESTEP))
			privcntl = SPU_PRIVCNTL_MODE_SINGLE_STEP;
		else
			privcntl = SPU_PRIVCNTL_MODE_NORMAL;

		ctx->ops->privcntl_write(ctx, privcntl);
		ctx->ops->npc_write(ctx, *npc);
	}

	ctx->ops->runcntl_write(ctx, runcntl);

	if (ctx->flags & SPU_CREATE_NOSCHED) {
		spuctx_switch_state(ctx, SPU_UTIL_USER);
	} else {

		if (ctx->state == SPU_STATE_SAVED) {
			ret = spu_activate(ctx, 0);
			if (ret)
				return ret;
		} else {
			spuctx_switch_state(ctx, SPU_UTIL_USER);
		}
	}

	set_bit(SPU_SCHED_SPU_RUN, &ctx->sched_flags);
	return 0;
}

static int spu_run_fini(struct spu_context *ctx, u32 *npc,
			       u32 *status)
{
	int ret = 0;

	spu_del_from_rq(ctx);

	*status = ctx->ops->status_read(ctx);
	*npc = ctx->ops->npc_read(ctx);

	spuctx_switch_state(ctx, SPU_UTIL_IDLE_LOADED);
	clear_bit(SPU_SCHED_SPU_RUN, &ctx->sched_flags);
	spu_switch_log_notify(NULL, ctx, SWITCH_LOG_EXIT, *status);
	spu_release(ctx);

	if (signal_pending(current))
		ret = -ERESTARTSYS;

	return ret;
}

/*
 * SPU syscall restarting is tricky because we violate the basic
 * assumption that the signal handler is running on the interrupted
 * thread. Here instead, the handler runs on PowerPC user space code,
 * while the syscall was called from the SPU.
 * This means we can only do a very rough approximation of POSIX
 * signal semantics.
 */
static int spu_handle_restartsys(struct spu_context *ctx, long *spu_ret,
			  unsigned int *npc)
{
	int ret;

	switch (*spu_ret) {
	case -ERESTARTSYS:
	case -ERESTARTNOINTR:
		/*
		 * Enter the regular syscall restarting for
		 * sys_spu_run, then restart the SPU syscall
		 * callback.
		 */
		*npc -= 8;
		ret = -ERESTARTSYS;
		break;
	case -ERESTARTNOHAND:
	case -ERESTART_RESTARTBLOCK:
		/*
		 * Restart block is too hard for now, just return -EINTR
		 * to the SPU.
		 * ERESTARTNOHAND comes from sys_pause, we also return
		 * -EINTR from there.
		 * Assume that we need to be restarted ourselves though.
		 */
		*spu_ret = -EINTR;
		ret = -ERESTARTSYS;
		break;
	default:
		printk(KERN_WARNING "%s: unexpected return code %ld\n",
			__func__, *spu_ret);
		ret = 0;
	}
	return ret;
}

static int spu_process_callback(struct spu_context *ctx)
{
	struct spu_syscall_block s;
	u32 ls_pointer, npc;
	void __iomem *ls;
	long spu_ret;
	int ret;

	/* get syscall block from local store */
	npc = ctx->ops->npc_read(ctx) & ~3;
	ls = (void __iomem *)ctx->ops->get_ls(ctx);
	ls_pointer = in_be32(ls + npc);
	if (ls_pointer > (LS_SIZE - sizeof(s)))
		return -EFAULT;
	memcpy_fromio(&s, ls + ls_pointer, sizeof(s));

	/* do actual syscall without pinning the spu */
	ret = 0;
	spu_ret = -ENOSYS;
	npc += 4;

	if (s.nr_ret < __NR_syscalls) {
		spu_release(ctx);
		/* do actual system call from here */
		spu_ret = spu_sys_callback(&s);
		if (spu_ret <= -ERESTARTSYS) {
			ret = spu_handle_restartsys(ctx, &spu_ret, &npc);
		}
		mutex_lock(&ctx->state_mutex);
		if (ret == -ERESTARTSYS)
			return ret;
	}

	/* need to re-get the ls, as it may have changed when we released the
	 * spu */
	ls = (void __iomem *)ctx->ops->get_ls(ctx);

	/* write result, jump over indirect pointer */
	memcpy_toio(ls + ls_pointer, &spu_ret, sizeof(spu_ret));
	ctx->ops->npc_write(ctx, npc);
	ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE);
	return ret;
}

long spufs_run_spu(struct spu_context *ctx, u32 *npc, u32 *event)
{
	int ret;
	struct spu *spu;
	u32 status;

	if (mutex_lock_interruptible(&ctx->run_mutex))
		return -ERESTARTSYS;

	ctx->event_return = 0;

	ret = spu_acquire(ctx);
	if (ret)
		goto out_unlock;

	spu_enable_spu(ctx);

	spu_update_sched_info(ctx);

	ret = spu_run_init(ctx, npc);
	if (ret) {
		spu_release(ctx);
		goto out;
	}

	do {
		ret = spufs_wait(ctx->stop_wq, spu_stopped(ctx, &status));
		if (unlikely(ret)) {
			/*
			 * This is nasty: we need the state_mutex for all the
			 * bookkeeping even if the syscall was interrupted by
			 * a signal. ewww.
			 */
			mutex_lock(&ctx->state_mutex);
			break;
		}
		spu = ctx->spu;
		if (unlikely(test_and_clear_bit(SPU_SCHED_NOTIFY_ACTIVE,
						&ctx->sched_flags))) {
			if (!(status & SPU_STATUS_STOPPED_BY_STOP)) {
				spu_switch_notify(spu, ctx);
				continue;
			}
		}

		spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);

		if ((status & SPU_STATUS_STOPPED_BY_STOP) &&
		    (status >> SPU_STOP_STATUS_SHIFT == 0x2104)) {
			ret = spu_process_callback(ctx);
			if (ret)
				break;
			status &= ~SPU_STATUS_STOPPED_BY_STOP;
		}
		ret = spufs_handle_class1(ctx);
		if (ret)
			break;

		ret = spufs_handle_class0(ctx);
		if (ret)
			break;

		if (signal_pending(current))
			ret = -ERESTARTSYS;
	} while (!ret && !(status & (SPU_STATUS_STOPPED_BY_STOP |
				      SPU_STATUS_STOPPED_BY_HALT |
				       SPU_STATUS_SINGLE_STEP)));

	spu_disable_spu(ctx);
	ret = spu_run_fini(ctx, npc, &status);
	spu_yield(ctx);

	if ((status & SPU_STATUS_STOPPED_BY_STOP) &&
	    (((status >> SPU_STOP_STATUS_SHIFT) & 0x3f00) == 0x2100))
		ctx->stats.libassist++;

	if ((ret == 0) ||
	    ((ret == -ERESTARTSYS) &&
	     ((status & SPU_STATUS_STOPPED_BY_HALT) ||
	      (status & SPU_STATUS_SINGLE_STEP) ||
	      ((status & SPU_STATUS_STOPPED_BY_STOP) &&
	       (status >> SPU_STOP_STATUS_SHIFT != 0x2104)))))
		ret = status;

	/* Note: we don't need to force_sig SIGTRAP on single-step
	 * since we have TIF_SINGLESTEP set, thus the kernel will do
	 * it upon return from the syscall anyawy
	 */
	if (unlikely(status & SPU_STATUS_SINGLE_STEP))
		ret = -ERESTARTSYS;

	else if (unlikely((status & SPU_STATUS_STOPPED_BY_STOP)
	    && (status >> SPU_STOP_STATUS_SHIFT) == 0x3fff)) {
		force_sig(SIGTRAP, current);
		ret = -ERESTARTSYS;
	}

out:
	*event = ctx->event_return;
out_unlock:
	mutex_unlock(&ctx->run_mutex);
	return ret;
}
Commit	Line	Data
0afacde3	1	#define DEBUG
0afacde3	2
ce8ab854 AB	3	#include <linux/wait.h>
	4	#include <linux/ptrace.h>
	5
	6	#include <asm/spu.h>
c6730ed4 JK	7	#include <asm/spu_priv1.h>
c6730ed4 JK	8	#include <asm/io.h>
cfff5b23	9	#include <asm/unistd.h>
ce8ab854 AB	10
	11	#include "spufs.h"
	12
	13	/* interrupt-level stop callback function. */
f3d69e05	14	void spufs_stop_callback(struct spu *spu, int irq)
ce8ab854 AB	15	{
	16	struct spu_context *ctx = spu->ctx;
	17
d6ad39bc JK	18	/*
	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.
	24	*/
	25	if (ctx) {
	26	/* Copy exception arguments into module specific structure */
f3d69e05 LB	27	switch(irq) {
	28	case 0 :
	29	ctx->csa.class_0_pending = spu->class_0_pending;
f3d69e05 LB	30	ctx->csa.class_0_dar = spu->class_0_dar;
	31	break;
	32	case 1 :
	33	ctx->csa.class_1_dsisr = spu->class_1_dsisr;
	34	ctx->csa.class_1_dar = spu->class_1_dar;
	35	break;
	36	case 2 :
	37	break;
	38	}
d6ad39bc JK	39
	40	/* ensure that the exception status has hit memory before a
	41	* thread waiting on the context's stop queue is woken */
	42	smp_wmb();
	43
	44	wake_up_all(&ctx->stop_wq);
	45	}
ce8ab854 AB	46	}
ce8ab854 AB	47
e65c2f6f	48	int spu_stopped(struct spu_context ctx, u32 stat)
ce8ab854	49	{
e65c2f6f LB	50	u64 dsisr;
e65c2f6f LB	51	u32 stopped;
ce8ab854	52
d84050f4 LB	53	stopped = SPU_STATUS_INVALID_INSTR \| SPU_STATUS_SINGLE_STEP \|
d84050f4 LB	54	SPU_STATUS_STOPPED_BY_HALT \| SPU_STATUS_STOPPED_BY_STOP;
36aaccc1	55
d84050f4 LB	56	top:
	57	*stat = ctx->ops->status_read(ctx);
	58	if (*stat & stopped) {
	59	/*
	60	* If the spu hasn't finished stopping, we need to
	61	* re-read the register to get the stopped value.
	62	*/
	63	if (*stat & SPU_STATUS_RUNNING)
	64	goto top;
e65c2f6f	65	return 1;
d84050f4	66	}
e65c2f6f	67
d84050f4	68	if (test_bit(SPU_SCHED_NOTIFY_ACTIVE, &ctx->sched_flags))
e65c2f6f LB	69	return 1;
e65c2f6f LB	70
f3d69e05	71	dsisr = ctx->csa.class_1_dsisr;
e65c2f6f	72	if (dsisr & (MFC_DSISR_PTE_NOT_FOUND \| MFC_DSISR_ACCESS_DENIED))
36aaccc1	73	return 1;
e65c2f6f LB	74
	75	if (ctx->csa.class_0_pending)
	76	return 1;
	77
	78	return 0;
ce8ab854 AB	79	}
ce8ab854 AB	80
c6730ed4 JK	81	static int spu_setup_isolated(struct spu_context *ctx)
	82	{
	83	int ret;
	84	u64 __iomem *mfc_cntl;
	85	u64 sr1;
	86	u32 status;
	87	unsigned long timeout;
	88	const u32 status_loading = SPU_STATUS_RUNNING
	89	\| SPU_STATUS_ISOLATED_STATE \| SPU_STATUS_ISOLATED_LOAD_STATUS;
	90
7ec18ab9	91	ret = -ENODEV;
c6730ed4	92	if (!isolated_loader)
c6730ed4 JK	93	goto out;
c6730ed4 JK	94
7ec18ab9 CH	95	/*
	96	* We need to exclude userspace access to the context.
	97	*
	98	* To protect against memory access we invalidate all ptes
	99	* and make sure the pagefault handlers block on the mutex.
	100	*/
	101	spu_unmap_mappings(ctx);
	102
c6730ed4 JK	103	mfc_cntl = &ctx->spu->priv2->mfc_control_RW;
	104
	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",
e48b1b45	113	__func__);
c6730ed4	114	ret = -EIO;
7ec18ab9	115	goto out;
c6730ed4 JK	116	}
	117	cond_resched();
	118	}
	119
	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);
	124
	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);
	129
	130	ctx->ops->runcntl_write(ctx,
	131	SPU_RUNCNTL_RUNNABLE \| SPU_RUNCNTL_ISOLATE);
	132
	133	ret = 0;
	134	timeout = jiffies + HZ;
	135	while (((status = ctx->ops->status_read(ctx)) & status_loading) ==
	136	status_loading) {
	137	if (time_after(jiffies, timeout)) {
	138	printk(KERN_ERR "%s: timeout waiting for loader\n",
e48b1b45	139	__func__);
c6730ed4 JK	140	ret = -EIO;
	141	goto out_drop_priv;
	142	}
	143	cond_resched();
	144	}
	145
	146	if (!(status & SPU_STATUS_RUNNING)) {
	147	/* If isolated LOAD has failed: run SPU, we will get a stop-and
	148	* signal later. */
e48b1b45	149	pr_debug("%s: isolated LOAD failed\n", __func__);
c6730ed4 JK	150	ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE);
c6730ed4 JK	151	ret = -EACCES;
7ec18ab9 CH	152	goto out_drop_priv;
7ec18ab9 CH	153	}
c6730ed4	154
7ec18ab9	155	if (!(status & SPU_STATUS_ISOLATED_STATE)) {
c6730ed4	156	/* This isn't allowed by the CBEA, but check anyway */
e48b1b45	157	pr_debug("%s: SPU fell out of isolated mode?\n", __func__);
c6730ed4 JK	158	ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_STOP);
c6730ed4 JK	159	ret = -EINVAL;
7ec18ab9	160	goto out_drop_priv;
c6730ed4 JK	161	}
	162
	163	out_drop_priv:
	164	/* Finished accessing the loader. Drop kernel mode */
	165	sr1 \|= MFC_STATE1_PROBLEM_STATE_MASK;
	166	spu_mfc_sr1_set(ctx->spu, sr1);
	167
c6730ed4 JK	168	out:
	169	return ret;
	170	}
	171
36aaccc1	172	static int spu_run_init(struct spu_context ctx, u32 npc)
ce8ab854	173	{
e65c2f6f	174	unsigned long runcntl = SPU_RUNCNTL_RUNNABLE;
91569531	175	int ret;
cc210b3e	176
27ec41d3 AD	177	spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);
27ec41d3 AD	178
e65c2f6f LB	179	/*
	180	* NOSCHED is synchronous scheduling with respect to the caller.
	181	* The caller waits for the context to be loaded.
	182	*/
	183	if (ctx->flags & SPU_CREATE_NOSCHED) {
91569531	184	if (ctx->state == SPU_STATE_SAVED) {
91569531 LB	185	ret = spu_activate(ctx, 0);
	186	if (ret)
	187	return ret;
	188	}
e65c2f6f	189	}
aa45e256	190
e65c2f6f LB	191	/*
	192	* Apply special setup as required.
	193	*/
	194	if (ctx->flags & SPU_CREATE_ISOLATE) {
c6730ed4	195	if (!(ctx->ops->status_read(ctx) & SPU_STATUS_ISOLATED_STATE)) {
91569531	196	ret = spu_setup_isolated(ctx);
7ec18ab9	197	if (ret)
aa45e256	198	return ret;
c6730ed4 JK	199	}
c6730ed4 JK	200
91569531 LB	201	/*
	202	* If userspace has set the runcntrl register (eg, to
	203	* issue an isolated exit), we need to re-set it here
	204	*/
c6730ed4 JK	205	runcntl = ctx->ops->runcntl_read(ctx) &
	206	(SPU_RUNCNTL_RUNNABLE \| SPU_RUNCNTL_ISOLATE);
	207	if (runcntl == 0)
	208	runcntl = SPU_RUNCNTL_RUNNABLE;
2eb1b120	209	} else {
cc210b3e LB	210	unsigned long privcntl;
cc210b3e LB	211
05169237	212	if (test_thread_flag(TIF_SINGLESTEP))
cc210b3e LB	213	privcntl = SPU_PRIVCNTL_MODE_SINGLE_STEP;
	214	else
	215	privcntl = SPU_PRIVCNTL_MODE_NORMAL;
cc210b3e	216
cc210b3e	217	ctx->ops->privcntl_write(ctx, privcntl);
d9dd421f JK	218	ctx->ops->npc_write(ctx, *npc);
	219	}
	220
	221	ctx->ops->runcntl_write(ctx, runcntl);
	222
	223	if (ctx->flags & SPU_CREATE_NOSCHED) {
	224	spuctx_switch_state(ctx, SPU_UTIL_USER);
	225	} else {
c6730ed4	226
91569531	227	if (ctx->state == SPU_STATE_SAVED) {
91569531 LB	228	ret = spu_activate(ctx, 0);
	229	if (ret)
	230	return ret;
e65c2f6f LB	231	} else {
e65c2f6f LB	232	spuctx_switch_state(ctx, SPU_UTIL_USER);
91569531	233	}
91569531	234	}
27ec41d3	235
ce7c191b	236	set_bit(SPU_SCHED_SPU_RUN, &ctx->sched_flags);
aa45e256	237	return 0;
ce8ab854 AB	238	}
ce8ab854 AB	239
36aaccc1 BN	240	static int spu_run_fini(struct spu_context ctx, u32 npc,
36aaccc1 BN	241	u32 *status)
ce8ab854 AB	242	{
	243	int ret = 0;
	244
e65c2f6f LB	245	spu_del_from_rq(ctx);
e65c2f6f LB	246
ce8ab854 AB	247	*status = ctx->ops->status_read(ctx);
ce8ab854 AB	248	*npc = ctx->ops->npc_read(ctx);
27ec41d3 AD	249
27ec41d3 AD	250	spuctx_switch_state(ctx, SPU_UTIL_IDLE_LOADED);
ce7c191b	251	clear_bit(SPU_SCHED_SPU_RUN, &ctx->sched_flags);
f5ed0eb6	252	spu_switch_log_notify(NULL, ctx, SWITCH_LOG_EXIT, *status);
ce8ab854 AB	253	spu_release(ctx);
	254
	255	if (signal_pending(current))
	256	ret = -ERESTARTSYS;
2ebb2477	257
ce8ab854 AB	258	return ret;
	259	}
	260
2dd14934 AB	261	/*
	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
	267	* signal semantics.
	268	*/
1238819a	269	static int spu_handle_restartsys(struct spu_context ctx, long spu_ret,
2dd14934 AB	270	unsigned int *npc)
	271	{
	272	int ret;
	273
	274	switch (*spu_ret) {
	275	case -ERESTARTSYS:
	276	case -ERESTARTNOINTR:
	277	/*
	278	* Enter the regular syscall restarting for
	279	* sys_spu_run, then restart the SPU syscall
	280	* callback.
	281	*/
	282	*npc -= 8;
	283	ret = -ERESTARTSYS;
	284	break;
	285	case -ERESTARTNOHAND:
	286	case -ERESTART_RESTARTBLOCK:
	287	/*
	288	* Restart block is too hard for now, just return -EINTR
	289	* to the SPU.
	290	* ERESTARTNOHAND comes from sys_pause, we also return
	291	* -EINTR from there.
	292	* Assume that we need to be restarted ourselves though.
	293	*/
	294	*spu_ret = -EINTR;
	295	ret = -ERESTARTSYS;
	296	break;
	297	default:
	298	printk(KERN_WARNING "%s: unexpected return code %ld\n",
e48b1b45	299	__func__, *spu_ret);
2dd14934 AB	300	ret = 0;
	301	}
	302	return ret;
	303	}
	304
1238819a	305	static int spu_process_callback(struct spu_context *ctx)
2dd14934 AB	306	{
	307	struct spu_syscall_block s;
	308	u32 ls_pointer, npc;
9e2fe2ce	309	void __iomem *ls;
2dd14934	310	long spu_ret;
d29694f0	311	int ret;
2dd14934 AB	312
2dd14934 AB	313	/* get syscall block from local store */
9e2fe2ce AM	314	npc = ctx->ops->npc_read(ctx) & ~3;
	315	ls = (void __iomem *)ctx->ops->get_ls(ctx);
	316	ls_pointer = in_be32(ls + npc);
2dd14934 AB	317	if (ls_pointer > (LS_SIZE - sizeof(s)))
2dd14934 AB	318	return -EFAULT;
9e2fe2ce	319	memcpy_fromio(&s, ls + ls_pointer, sizeof(s));
2dd14934 AB	320
	321	/* do actual syscall without pinning the spu */
	322	ret = 0;
	323	spu_ret = -ENOSYS;
	324	npc += 4;
	325
	326	if (s.nr_ret < __NR_syscalls) {
	327	spu_release(ctx);
	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);
	332	}
d29694f0	333	mutex_lock(&ctx->state_mutex);
2dd14934 AB	334	if (ret == -ERESTARTSYS)
	335	return ret;
	336	}
	337
4eb5aef5 JK	338	/* need to re-get the ls, as it may have changed when we released the
	339	* spu */
	340	ls = (void __iomem *)ctx->ops->get_ls(ctx);
	341
2dd14934	342	/* write result, jump over indirect pointer */
9e2fe2ce	343	memcpy_toio(ls + ls_pointer, &spu_ret, sizeof(spu_ret));
2dd14934 AB	344	ctx->ops->npc_write(ctx, npc);
	345	ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE);
	346	return ret;
	347	}
	348
50af32a9	349	long spufs_run_spu(struct spu_context ctx, u32 npc, u32 *event)
ce8ab854 AB	350	{
ce8ab854 AB	351	int ret;
36aaccc1	352	struct spu *spu;
9add11da	353	u32 status;
ce8ab854	354
e45d48a3	355	if (mutex_lock_interruptible(&ctx->run_mutex))
ce8ab854 AB	356	return -ERESTARTSYS;
ce8ab854 AB	357
9add11da	358	ctx->event_return = 0;
aa45e256	359
c9101bdb CH	360	ret = spu_acquire(ctx);
	361	if (ret)
	362	goto out_unlock;
2cf2b3b4	363
c0bace5c JK	364	spu_enable_spu(ctx);
c0bace5c JK	365
91569531	366	spu_update_sched_info(ctx);
aa45e256 CH	367
	368	ret = spu_run_init(ctx, npc);
	369	if (ret) {
	370	spu_release(ctx);
ce8ab854	371	goto out;
aa45e256	372	}
ce8ab854 AB	373
ce8ab854 AB	374	do {
9add11da	375	ret = spufs_wait(ctx->stop_wq, spu_stopped(ctx, &status));
eebead5b CH	376	if (unlikely(ret)) {
	377	/*
	378	* This is nasty: we need the state_mutex for all the
	379	* bookkeeping even if the syscall was interrupted by
	380	* a signal. ewww.
	381	*/
	382	mutex_lock(&ctx->state_mutex);
ce8ab854	383	break;
eebead5b	384	}
36aaccc1 BN	385	spu = ctx->spu;
	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);
	390	continue;
	391	}
	392	}
27ec41d3 AD	393
	394	spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);
	395
9add11da AB	396	if ((status & SPU_STATUS_STOPPED_BY_STOP) &&
9add11da AB	397	(status >> SPU_STOP_STATUS_SHIFT == 0x2104)) {
2dd14934 AB	398	ret = spu_process_callback(ctx);
	399	if (ret)
	400	break;
9add11da	401	status &= ~SPU_STATUS_STOPPED_BY_STOP;
2dd14934	402	}
57dace23 AB	403	ret = spufs_handle_class1(ctx);
	404	if (ret)
	405	break;
	406
d6ad39bc JK	407	ret = spufs_handle_class0(ctx);
	408	if (ret)
	409	break;
	410
d6ad39bc JK	411	if (signal_pending(current))
d6ad39bc JK	412	ret = -ERESTARTSYS;
9add11da	413	} while (!ret && !(status & (SPU_STATUS_STOPPED_BY_STOP \|
05169237 BH	414	SPU_STATUS_STOPPED_BY_HALT \|
05169237 BH	415	SPU_STATUS_SINGLE_STEP)));
ce8ab854	416
c25620d7	417	spu_disable_spu(ctx);
9add11da	418	ret = spu_run_fini(ctx, npc, &status);
ce8ab854 AB	419	spu_yield(ctx);
ce8ab854 AB	420
e66686b4 LB	421	if ((status & SPU_STATUS_STOPPED_BY_STOP) &&
	422	(((status >> SPU_STOP_STATUS_SHIFT) & 0x3f00) == 0x2100))
	423	ctx->stats.libassist++;
	424
2ebb2477 MN	425	if ((ret == 0) \|\|
	426	((ret == -ERESTARTSYS) &&
	427	((status & SPU_STATUS_STOPPED_BY_HALT) \|\|
05169237	428	(status & SPU_STATUS_SINGLE_STEP) \|\|
2ebb2477 MN	429	((status & SPU_STATUS_STOPPED_BY_STOP) &&
	430	(status >> SPU_STOP_STATUS_SHIFT != 0x2104)))))
	431	ret = status;
	432
05169237 BH	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
	436	*/
60cf54db JK	437	if (unlikely(status & SPU_STATUS_SINGLE_STEP))
	438	ret = -ERESTARTSYS;
	439
	440	else if (unlikely((status & SPU_STATUS_STOPPED_BY_STOP)
	441	&& (status >> SPU_STOP_STATUS_SHIFT) == 0x3fff)) {
c2b2226c AB	442	force_sig(SIGTRAP, current);
c2b2226c AB	443	ret = -ERESTARTSYS;
2ebb2477 MN	444	}
2ebb2477 MN	445
ce8ab854	446	out:
9add11da	447	*event = ctx->event_return;
c9101bdb	448	out_unlock:
e45d48a3	449	mutex_unlock(&ctx->run_mutex);
ce8ab854 AB	450	return ret;
ce8ab854 AB	451	}