[Intel-gfx] [PATCH v2] drm/i915/mocs: Program MOCS for all engines on init

[Peter Antoine]

Hi Chris,

Just posted patch that moves to the engine->init_hw().

Have moved the L3CC registers programming out of the function and left in 
the same place as the original function was. These registers are shared 
with all engines.

Peter.

On Thu, 10 Mar 2016, Chris Wilson wrote:

> On Thu, Mar 10, 2016 at 08:22:58PM +0000, Peter Antoine wrote:
>> Allow for the MOCS to be programmed for all engines.
>> Currently we program the MOCS when the first render batch
>> goes through. This works on most platforms but fails on
>> platforms that do not run a render batch early,
>> i.e. headless servers. The patch now programs all initialised engines
>> on init and the RCS is programmed again within the initial batch. This
>> is done for predictable consistency with regards to the hardware
>> context.
>>
>> Hardware context loading sets the values of the MOCS for RCS
>> and L3CC. Programming them from within the batch makes sure that
>> the render context is valid, no matter what the previous state of
>> the saved-context was.
>>
>> Signed-off-by: Peter Antoine <peter.antoine at intel.com>
>> ---
>>  drivers/gpu/drm/i915/i915_gem.c   |   3 +
>>  drivers/gpu/drm/i915/intel_mocs.c | 138 ++++++++++++++++++++++++++++++++++----
>>  drivers/gpu/drm/i915/intel_mocs.h |   1 +
>>  3 files changed, 130 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
>> index b854af2..05c9fcb 100644
>> --- a/drivers/gpu/drm/i915/i915_gem.c
>> +++ b/drivers/gpu/drm/i915/i915_gem.c
>> @@ -32,6 +32,7 @@
>>  #include "i915_vgpu.h"
>>  #include "i915_trace.h"
>>  #include "intel_drv.h"
>> +#include "intel_mocs.h"
>>  #include <linux/shmem_fs.h>
>>  #include <linux/slab.h>
>>  #include <linux/swap.h>
>> @@ -4882,6 +4883,8 @@ i915_gem_init_hw(struct drm_device *dev)
>>  			goto out;
>>  	}
>>
>> +	intel_program_mocs_engines(dev);
>
> Registers to be written when enabling the engine are called from
> engine->init_hw() in the line above. Please add this state there, which
> can then be specialised via vfunc if so desired.
> -Chris
>
>

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    Peter Antoine (Android Graphics Driver Software Engineer)
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