diff options
author | Jeremy Kerr <jk@ozlabs.org> | 2006-11-20 18:45:10 +0100 |
---|---|---|
committer | Paul Mackerras <paulus@samba.org> | 2006-12-04 20:40:06 +1100 |
commit | c6730ed4c280ff9e55766796523c94a7d111da09 (patch) | |
tree | 6635d2a52f7e8021e4565edd0b66a752d4d699ad /arch/powerpc/platforms/cell/spufs/run.c | |
parent | 3960c260204bc33404a6e54e9dcd44f1f83bc701 (diff) | |
download | op-kernel-dev-c6730ed4c280ff9e55766796523c94a7d111da09.zip op-kernel-dev-c6730ed4c280ff9e55766796523c94a7d111da09.tar.gz |
[POWERPC] spufs: Load isolation kernel from spu_run
In order to fit with the "don't-run-spus-outside-of-spu_run" model, this
patch starts the isolated-mode loader in spu_run, rather than
spu_create. If spu_run is passed an isolated-mode context that isn't in
isolated mode state, it will run the loader.
This fixes potential races with the isolated SPE app doing a
stop-and-signal before the PPE has called spu_run: bugzilla #29111.
Also (in conjunction with a mambo patch), this addresses #28565, as we
always set the runcntrl register when entering spu_run.
It is up to libspe to ensure that isolated-mode apps are cleaned up
after running to completion - ie, put the app through the "ISOLATE EXIT"
state (see Ch11 of the CBEA).
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/platforms/cell/spufs/run.c')
-rw-r--r-- | arch/powerpc/platforms/cell/spufs/run.c | 117 |
1 files changed, 110 insertions, 7 deletions
diff --git a/arch/powerpc/platforms/cell/spufs/run.c b/arch/powerpc/platforms/cell/spufs/run.c index 212b9c2..1be4e33 100644 --- a/arch/powerpc/platforms/cell/spufs/run.c +++ b/arch/powerpc/platforms/cell/spufs/run.c @@ -4,6 +4,8 @@ #include <linux/ptrace.h> #include <asm/spu.h> +#include <asm/spu_priv1.h> +#include <asm/io.h> #include <asm/unistd.h> #include "spufs.h" @@ -51,21 +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 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(); + } + + /* 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; - if ((ret = spu_acquire_runnable(ctx)) != 0) + ret = spu_acquire_runnable(ctx); + if (ret) return ret; - /* if we're in isolated mode, we would have started the SPU - * earlier, so don't do it again now. */ - if (!(ctx->flags & SPU_CREATE_ISOLATE)) { + 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 0; + + ctx->ops->runcntl_write(ctx, runcntl); + return ret; } static inline int spu_run_fini(struct spu_context *ctx, u32 * npc, |