[Mesa-dev] [PATCH resend 7/7] i965: Disable HW-binding tables on batch finish for Broadwell

[Abdiel Janulgue]

On 06/02/2015 09:31 AM, Kenneth Graunke wrote:
> On Monday, June 01, 2015 03:14:30 PM Abdiel Janulgue wrote:
>> This is needed since kernel doesn't support RS context save and
>> restore on BDW yet. So manually disable hw-generated binding tables
>> when done using it in the batch. Otherwise the GPU would no longer
>> accept software binding tables submitted by other clients including
>> but not limited to the Xorg driver.
>>
>> Signed-off-by: Abdiel Janulgue <abdiel.janulgue at linux.intel.com>
>> ---
>>  src/mesa/drivers/dri/i965/intel_batchbuffer.c | 11 +++++++++++
>>  src/mesa/drivers/dri/i965/intel_batchbuffer.h |  3 ++-
>>  2 files changed, 13 insertions(+), 1 deletion(-)
> 
> This seems fairly awful.  The kernel should prevent userspace from
> breaking other userspace...in the hardware context world, this really
> doesn't feel like our job.
> 
> Why didn't you just update your kernel patch for Broadwell?  i.e. make
> 
> drm/i915: Enable Resource Streamer state save/restore in HSW
> 
> do:
> +       if (IS_HASWELL(ring->dev) || INTEL_INFO(ring->dev)->gen >= 8)
> 
> instead of:
> +       if (IS_HASWELL(ring->dev))
> 
> It looks like the MI_SET_CONTEXT RS save/restore bits you used on
> Haswell still exist on Broadwell.  Do they not work or something?
> 
> 

I was hoping to have a follow-up for GEN8 as well once the initial
kernel patches get merged  :)