fedora core 6 1.2949 + vserver 2.2.0
[linux-2.6.git] / arch / powerpc / platforms / cell / spufs / run.c
index 18ea886..1acc2ff 100644 (file)
@@ -1,7 +1,12 @@
+#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"
 
@@ -13,6 +18,27 @@ void spufs_stop_callback(struct spu *spu)
        wake_up_all(&ctx->stop_wq);
 }
 
+void spufs_dma_callback(struct spu *spu, int type)
+{
+       struct spu_context *ctx = spu->ctx;
+
+       if (ctx->flags & SPU_CREATE_EVENTS_ENABLED) {
+               ctx->event_return |= type;
+               wake_up_all(&ctx->stop_wq);
+       } else {
+               switch (type) {
+               case SPE_EVENT_DMA_ALIGNMENT:
+               case SPE_EVENT_SPE_DATA_STORAGE:
+               case SPE_EVENT_INVALID_DMA:
+                       force_sig(SIGBUS, /* info, */ current);
+                       break;
+               case SPE_EVENT_SPE_ERROR:
+                       force_sig(SIGILL, /* info */ current);
+                       break;
+               }
+       }
+}
+
 static inline int spu_stopped(struct spu_context *ctx, u32 * stat)
 {
        struct spu *spu;
@@ -27,16 +53,122 @@ static inline int spu_stopped(struct spu_context *ctx, u32 * stat)
        return (!(*stat & 0x1) || pte_fault || spu->class_0_pending) ? 1 : 0;
 }
 
-static inline int spu_run_init(struct spu_context *ctx, u32 * npc,
-                              u32 * status)
+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;
+
+       if (!isolated_loader)
+               return -ENODEV;
+
+       ret = spu_acquire_exclusive(ctx);
+       if (ret)
+               goto out;
+
+       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",
+                                       __FUNCTION__);
+                       ret = -EIO;
+                       goto out_unlock;
+               }
+               cond_resched();
+       }
 
-       if ((ret = spu_acquire_runnable(ctx)) != 0)
+       /* 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",
+                                       __FUNCTION__);
+                       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", __FUNCTION__);
+               ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE);
+               ret = -EACCES;
+
+       } else 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", __FUNCTION__);
+               ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_STOP);
+               ret = -EINVAL;
+       }
+
+out_drop_priv:
+       /* Finished accessing the loader. Drop kernel mode */
+       sr1 |= MFC_STATE1_PROBLEM_STATE_MASK;
+       spu_mfc_sr1_set(ctx->spu, sr1);
+
+out_unlock:
+       spu_release_exclusive(ctx);
+out:
+       return ret;
+}
+
+static inline int spu_run_init(struct spu_context *ctx, u32 * npc)
+{
+       int ret;
+       unsigned long runcntl = SPU_RUNCNTL_RUNNABLE;
+
+       ret = spu_acquire_runnable(ctx);
+       if (ret)
                return ret;
-       ctx->ops->npc_write(ctx, *npc);
-       ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE);
-       return 0;
+
+       if (ctx->flags & SPU_CREATE_ISOLATE) {
+               if (!(ctx->ops->status_read(ctx) & SPU_STATUS_ISOLATED_STATE)) {
+                       /* Need to release ctx, because spu_setup_isolated will
+                        * acquire it exclusively.
+                        */
+                       spu_release(ctx);
+                       ret = spu_setup_isolated(ctx);
+                       if (!ret)
+                               ret = spu_acquire_runnable(ctx);
+               }
+
+               /* 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
+               ctx->ops->npc_write(ctx, *npc);
+
+       ctx->ops->runcntl_write(ctx, runcntl);
+       return ret;
 }
 
 static inline int spu_run_fini(struct spu_context *ctx, u32 * npc,
@@ -50,13 +182,7 @@ static inline int spu_run_fini(struct spu_context *ctx, u32 * npc,
 
        if (signal_pending(current))
                ret = -ERESTARTSYS;
-       if (unlikely(current->ptrace & PT_PTRACED)) {
-               if ((*status & SPU_STATUS_STOPPED_BY_STOP)
-                   && (*status >> SPU_STOP_STATUS_SHIFT) == 0x3fff) {
-                       force_sig(SIGTRAP, current);
-                       ret = -ERESTARTSYS;
-               }
-       }
+
        return ret;
 }
 
@@ -71,11 +197,95 @@ static inline int spu_reacquire_runnable(struct spu_context *ctx, u32 *npc,
                       SPU_STATUS_STOPPED_BY_HALT)) {
                return *status;
        }
-       if ((ret = spu_run_init(ctx, npc, status)) != 0)
+       if ((ret = spu_run_init(ctx, npc)) != 0)
                return ret;
        return 0;
 }
 
+/*
+ * 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.
+ */
+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",
+                       __FUNCTION__, *spu_ret);
+               ret = 0;
+       }
+       return ret;
+}
+
+int spu_process_callback(struct spu_context *ctx)
+{
+       struct spu_syscall_block s;
+       u32 ls_pointer, npc;
+       char *ls;
+       long spu_ret;
+       int ret;
+
+       /* get syscall block from local store */
+       npc = ctx->ops->npc_read(ctx);
+       ls = ctx->ops->get_ls(ctx);
+       ls_pointer = *(u32*)(ls + npc);
+       if (ls_pointer > (LS_SIZE - sizeof(s)))
+               return -EFAULT;
+       memcpy(&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);
+               }
+               spu_acquire(ctx);
+               if (ret == -ERESTARTSYS)
+                       return ret;
+       }
+
+       /* write result, jump over indirect pointer */
+       memcpy(ls + ls_pointer, &spu_ret, sizeof (spu_ret));
+       ctx->ops->npc_write(ctx, npc);
+       ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE);
+       return ret;
+}
+
 static inline int spu_process_events(struct spu_context *ctx)
 {
        struct spu *spu = ctx->spu;
@@ -92,39 +302,62 @@ static inline int spu_process_events(struct spu_context *ctx)
 }
 
 long spufs_run_spu(struct file *file, struct spu_context *ctx,
-                  u32 * npc, u32 * status)
+                  u32 *npc, u32 *event)
 {
        int ret;
+       u32 status;
 
        if (down_interruptible(&ctx->run_sema))
                return -ERESTARTSYS;
 
-       ret = spu_run_init(ctx, npc, status);
+       ctx->ops->master_start(ctx);
+       ctx->event_return = 0;
+       ret = spu_run_init(ctx, npc);
        if (ret)
                goto out;
 
        do {
-               ret = spufs_wait(ctx->stop_wq, spu_stopped(ctx, status));
+               ret = spufs_wait(ctx->stop_wq, spu_stopped(ctx, &status));
                if (unlikely(ret))
                        break;
+               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;
+               }
                if (unlikely(ctx->state != SPU_STATE_RUNNABLE)) {
-                       ret = spu_reacquire_runnable(ctx, npc, status);
+                       ret = spu_reacquire_runnable(ctx, npc, &status);
                        if (ret)
-                               goto out;
+                               goto out2;
                        continue;
                }
                ret = spu_process_events(ctx);
 
-       } while (!ret && !(*status & (SPU_STATUS_STOPPED_BY_STOP |
+       } while (!ret && !(status & (SPU_STATUS_STOPPED_BY_STOP |
                                      SPU_STATUS_STOPPED_BY_HALT)));
 
-       ctx->ops->runcntl_stop(ctx);
-       ret = spu_run_fini(ctx, npc, status);
-       if (!ret)
-               ret = *status;
+       ctx->ops->master_stop(ctx);
+       ret = spu_run_fini(ctx, npc, &status);
        spu_yield(ctx);
 
+out2:
+       if ((ret == 0) ||
+           ((ret == -ERESTARTSYS) &&
+            ((status & SPU_STATUS_STOPPED_BY_HALT) ||
+             ((status & SPU_STATUS_STOPPED_BY_STOP) &&
+              (status >> SPU_STOP_STATUS_SHIFT != 0x2104)))))
+               ret = status;
+
+       if ((status & SPU_STATUS_STOPPED_BY_STOP)
+           && (status >> SPU_STOP_STATUS_SHIFT) == 0x3fff) {
+               force_sig(SIGTRAP, current);
+               ret = -ERESTARTSYS;
+       }
+
 out:
+       *event = ctx->event_return;
        up(&ctx->run_sema);
        return ret;
 }