Nouveau - Jan 2010 - [PATCH 3/3] drm/nv50: wait for pgraph to idle before unloading the context

- This should fix the problem with gpu hangs people have had when closing
channels.

Signed-off-by: Maarten Maathuis <madman2003 at gmail.com>
---
 drivers/gpu/drm/nouveau/nv50_graph.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nv50_graph.c
b/drivers/gpu/drm/nouveau/nv50_graph.c
index 444a46b..d6897cf 100644
--- a/drivers/gpu/drm/nouveau/nv50_graph.c
+++ b/drivers/gpu/drm/nouveau/nv50_graph.c
@@ -282,6 +282,7 @@ nv50_graph_unload_context(struct drm_device *dev)
 		return 0;
 	inst &= NV50_PGRAPH_CTXCTL_CUR_INSTANCE;
 
+	nouveau_wait_for_idle(dev);
 	nv_wr32(dev, 0x400500, fifo & ~1);
 	nv_wr32(dev, 0x400784, inst);
 	nv_wr32(dev, 0x400824, nv_rd32(dev, 0x400824) | 0x20);
-- 
1.6.6

This patch alone, so ignore the 3/3. I think this fixes the channel
unload hang issues in a less obscure way. Feedback appreciated as
usual.

On Mon, Jan 11, 2010 at 9:18 PM, Maarten Maathuis <madman2003 at
gmail.com> wrote:
> - This should fix the problem with gpu hangs people have had when closing
> channels.
>
> Signed-off-by: Maarten Maathuis <madman2003 at gmail.com>
> ---
> ?drivers/gpu/drm/nouveau/nv50_graph.c | ? ?1 +
> ?1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/nv50_graph.c
b/drivers/gpu/drm/nouveau/nv50_graph.c
> index 444a46b..d6897cf 100644
> --- a/drivers/gpu/drm/nouveau/nv50_graph.c
> +++ b/drivers/gpu/drm/nouveau/nv50_graph.c
> @@ -282,6 +282,7 @@ nv50_graph_unload_context(struct drm_device *dev)
> ? ? ? ? ? ? ? ?return 0;
> ? ? ? ?inst &= NV50_PGRAPH_CTXCTL_CUR_INSTANCE;
>
> + ? ? ? nouveau_wait_for_idle(dev);
> ? ? ? ?nv_wr32(dev, 0x400500, fifo & ~1);
> ? ? ? ?nv_wr32(dev, 0x400784, inst);
> ? ? ? ?nv_wr32(dev, 0x400824, nv_rd32(dev, 0x400824) | 0x20);
> --
> 1.6.6
>
>

This patch *is* alone, sorry for the typo.

On Mon, Jan 11, 2010 at 9:20 PM, Maarten Maathuis <madman2003 at
gmail.com> wrote:
> This patch alone, so ignore the 3/3. I think this fixes the channel
> unload hang issues in a less obscure way. Feedback appreciated as
> usual.
>
> On Mon, Jan 11, 2010 at 9:18 PM, Maarten Maathuis <madman2003 at
gmail.com> wrote:
>> - This should fix the problem with gpu hangs people have had when
closing
>> channels.
>>
>> Signed-off-by: Maarten Maathuis <madman2003 at gmail.com>
>> ---
>> ?drivers/gpu/drm/nouveau/nv50_graph.c | ? ?1 +
>> ?1 files changed, 1 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/nouveau/nv50_graph.c
b/drivers/gpu/drm/nouveau/nv50_graph.c
>> index 444a46b..d6897cf 100644
>> --- a/drivers/gpu/drm/nouveau/nv50_graph.c
>> +++ b/drivers/gpu/drm/nouveau/nv50_graph.c
>> @@ -282,6 +282,7 @@ nv50_graph_unload_context(struct drm_device *dev)
>> ? ? ? ? ? ? ? ?return 0;
>> ? ? ? ?inst &= NV50_PGRAPH_CTXCTL_CUR_INSTANCE;
>>
>> + ? ? ? nouveau_wait_for_idle(dev);
>> ? ? ? ?nv_wr32(dev, 0x400500, fifo & ~1);
>> ? ? ? ?nv_wr32(dev, 0x400784, inst);
>> ? ? ? ?nv_wr32(dev, 0x400824, nv_rd32(dev, 0x400824) | 0x20);
>> --
>> 1.6.6
>>
>>
>

A few comments are in order, i noticed that this additional
wait_for_idle does cause delays sometimes (obviously). and it seems
like an excellent way to do a DOS attack on your gpu. fbcon is visibly
lagging sometimes and even unusable (gpu is not locked up,  X works
fine started from ssh). This seems like something to consider when
choosing the preferred solution.

On Mon, Jan 11, 2010 at 9:22 PM, Maarten Maathuis <madman2003 at
gmail.com> wrote:
> This patch *is* alone, sorry for the typo.
>
> On Mon, Jan 11, 2010 at 9:20 PM, Maarten Maathuis <madman2003 at
gmail.com> wrote:
>> This patch alone, so ignore the 3/3. I think this fixes the channel
>> unload hang issues in a less obscure way. Feedback appreciated as
>> usual.
>>
>> On Mon, Jan 11, 2010 at 9:18 PM, Maarten Maathuis <madman2003 at
gmail.com> wrote:
>>> - This should fix the problem with gpu hangs people have had when
closing
>>> channels.
>>>
>>> Signed-off-by: Maarten Maathuis <madman2003 at gmail.com>
>>> ---
>>> ?drivers/gpu/drm/nouveau/nv50_graph.c | ? ?1 +
>>> ?1 files changed, 1 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/nouveau/nv50_graph.c
b/drivers/gpu/drm/nouveau/nv50_graph.c
>>> index 444a46b..d6897cf 100644
>>> --- a/drivers/gpu/drm/nouveau/nv50_graph.c
>>> +++ b/drivers/gpu/drm/nouveau/nv50_graph.c
>>> @@ -282,6 +282,7 @@ nv50_graph_unload_context(struct drm_device
*dev)
>>> ? ? ? ? ? ? ? ?return 0;
>>> ? ? ? ?inst &= NV50_PGRAPH_CTXCTL_CUR_INSTANCE;
>>>
>>> + ? ? ? nouveau_wait_for_idle(dev);
>>> ? ? ? ?nv_wr32(dev, 0x400500, fifo & ~1);
>>> ? ? ? ?nv_wr32(dev, 0x400784, inst);
>>> ? ? ? ?nv_wr32(dev, 0x400824, nv_rd32(dev, 0x400824) | 0x20);
>>> --
>>> 1.6.6
>>>
>>>
>>
>