gpu: nvgpu: Do not send WFI when finishing channel

The channel teardown process sends a WFI method to ensure that all
work has been completed. But we also preempt the channel a while
later, which also ensures that all work is completed.

Remove the code for submitting WFI, and rely on preemption to handle
idling the pipe.

Change-Id: I2af029184440ee73e70d377f15690ddaf9b8599f
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/735067
Reviewed-on: http://git-master/r/737527
Reviewed-by: Alexander Van Brunt <avanbrunt@nvidia.com>
Tested-by: Alexander Van Brunt <avanbrunt@nvidia.com>
Reviewed-by: Automatic_Commit_Validation_User

1 files changed, 0 insertions, 81 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
index 1a5cf5c4..444a1c2f 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
@@ -1223,77 +1223,6 @@ bool gk20a_channel_update_and_check_timeout(struct channel_gk20a *ch,
                 ch->timeout_accumulated_ms > ch->timeout_ms_max;
 }
 
-
-/* Issue a syncpoint increment *preceded* by a wait-for-idle
- * command.  All commands on the channel will have been
- * consumed at the time the fence syncpoint increment occurs.
- */
-static int gk20a_channel_submit_wfi(struct channel_gk20a *c)
-{
-        struct priv_cmd_entry *cmd = NULL;
-        struct gk20a *g = c->g;
-        u32 free_count;
-        int err = 0;
-
-        if (c->has_timedout)
-                return -ETIMEDOUT;
-
-        update_gp_get(g, c);
-        free_count = gp_free_count(c);
-        if (unlikely(!free_count)) {
-                gk20a_err(dev_from_gk20a(g),
-                           "not enough gpfifo space");
-                return -EAGAIN;
-        }
-
-        mutex_lock(&c->submit_lock);
-
-        if (!c->sync) {
-                c->sync = gk20a_channel_sync_create(c);
-                if (!c->sync) {
-                        mutex_unlock(&c->submit_lock);
-                        return -ENOMEM;
-                }
-                if (g->ops.fifo.resetup_ramfc)
-                        err = g->ops.fifo.resetup_ramfc(c);
-                if (err)
-                        return err;
-        }
-
-        gk20a_fence_put(c->last_submit.pre_fence);
-        gk20a_fence_put(c->last_submit.post_fence);
-        c->last_submit.pre_fence = NULL;
-        c->last_submit.post_fence = NULL;
-
-        err = c->sync->incr_wfi(c->sync, &cmd, &c->last_submit.post_fence);
-        if (unlikely(err)) {
-                mutex_unlock(&c->submit_lock);
-                return err;
-        }
-
-        WARN_ON(!c->last_submit.post_fence->wfi);
-
-        ((struct gpfifo *)(c->gpfifo.mem.cpu_va))[c->gpfifo.put].entry0 = u64_lo32(cmd->gva);
-        ((struct gpfifo *)(c->gpfifo.mem.cpu_va))[c->gpfifo.put].entry1 = u64_hi32(cmd->gva) |
-                pbdma_gp_entry1_length_f(cmd->size);
-
-        c->gpfifo.put = (c->gpfifo.put + 1) & (c->gpfifo.entry_num - 1);
-
-        /* save gp_put */
-        cmd->gp_put = c->gpfifo.put;
-
-        gk20a_bar1_writel(g,
-                c->userd_gpu_va + 4 * ram_userd_gp_put_w(),
-                c->gpfifo.put);
-
-        mutex_unlock(&c->submit_lock);
-
-        gk20a_dbg_info("post-submit put %d, get %d, size %d",
-                c->gpfifo.put, c->gpfifo.get, c->gpfifo.entry_num);
-
-        return 0;
-}
-
 static u32 get_gp_free_count(struct channel_gk20a *c)
 {
         update_gp_get(c->g, c);
@@ -1726,16 +1655,6 @@ int gk20a_channel_finish(struct channel_gk20a *ch, unsigned long timeout)
         if (ch->has_timedout)
                 return -ETIMEDOUT;
 
-        if (!(fence && fence->wfi) && ch->obj_class != KEPLER_C) {
-                gk20a_dbg_fn("issuing wfi, incr to finish the channel");
-                err = gk20a_channel_submit_wfi(ch);
-                fence = ch->last_submit.post_fence;
-        }
-        if (err)
-                return err;
-
-        BUG_ON(!(fence && fence->wfi) && ch->obj_class != KEPLER_C);
-
         gk20a_dbg_fn("waiting for channel to finish thresh:%d sema:%p",
                      fence->syncpt_value, fence->semaphore);