--- /dev/null
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+
+#include <asm/spu.h>
+#include <asm/unistd.h>
+
+#include "spufs.h"
+
+/* interrupt-level stop callback function. */
+void spufs_stop_callback(struct spu *spu)
+{
+ struct spu_context *ctx = spu->ctx;
+
+ wake_up_all(&ctx->stop_wq);
+}
+
+static inline int spu_stopped(struct spu_context *ctx, u32 * stat)
+{
+ struct spu *spu;
+ u64 pte_fault;
+
+ *stat = ctx->ops->status_read(ctx);
+ if (ctx->state != SPU_STATE_RUNNABLE)
+ return 1;
+ spu = ctx->spu;
+ pte_fault = spu->dsisr &
+ (MFC_DSISR_PTE_NOT_FOUND | MFC_DSISR_ACCESS_DENIED);
+ 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)
+{
+ int ret;
+
+ if ((ret = spu_acquire_runnable(ctx)) != 0)
+ return ret;
+ ctx->ops->npc_write(ctx, *npc);
+ ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE);
+ return 0;
+}
+
+static inline int spu_run_fini(struct spu_context *ctx, u32 * npc,
+ u32 * status)
+{
+ int ret = 0;
+
+ *status = ctx->ops->status_read(ctx);
+ *npc = ctx->ops->npc_read(ctx);
+ spu_release(ctx);
+
+ 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;
+}
+
+static inline int spu_reacquire_runnable(struct spu_context *ctx, u32 *npc,
+ u32 *status)
+{
+ int ret;
+
+ if ((ret = spu_run_fini(ctx, npc, status)) != 0)
+ return ret;
+ if (*status & (SPU_STATUS_STOPPED_BY_STOP |
+ SPU_STATUS_STOPPED_BY_HALT)) {
+ return *status;
+ }
+ if ((ret = spu_run_init(ctx, npc, status)) != 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;
+ u64 pte_fault = MFC_DSISR_PTE_NOT_FOUND | MFC_DSISR_ACCESS_DENIED;
+ int ret = 0;
+
+ if (spu->dsisr & pte_fault)
+ ret = spu_irq_class_1_bottom(spu);
+ if (spu->class_0_pending)
+ ret = spu_irq_class_0_bottom(spu);
+ if (!ret && signal_pending(current))
+ ret = -ERESTARTSYS;
+ return ret;
+}
+
+long spufs_run_spu(struct file *file, struct spu_context *ctx,
+ u32 * npc, u32 * status)
+{
+ int ret;
+
+ if (down_interruptible(&ctx->run_sema))
+ return -ERESTARTSYS;
+
+ ret = spu_run_init(ctx, npc, status);
+ if (ret)
+ goto out;
+
+ do {
+ 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);
+ if (ret)
+ goto out;
+ continue;
+ }
+ ret = spu_process_events(ctx);
+
+ } 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;
+ spu_yield(ctx);
+
+out:
+ up(&ctx->run_sema);
+ return ret;
+}
+
git://git.onelab.eu / linux-2.6.git / blobdiff