Re: [Intel-gfx] [PATCH 1/1] drm/i915/mtl: enable local stolen memory

["Iddamsetty, Aravind" <aravind.iddamsetty@intel.com>]

On 22-09-2022 19:26, Lucas De Marchi wrote:
> On Wed, Sep 21, 2022 at 12:00:38PM +0530, Iddamsetty, Aravind wrote:
>> replying here for earlier comments too.
>>
>> On 21-09-2022 01:35, Lucas De Marchi wrote:
>>> On Tue, Sep 20, 2022 at 01:31:49AM -0700, Lucas De Marchi wrote:
>>>> On Tue, Sep 20, 2022 at 12:49:40PM +0530, Aravind Iddamsetty wrote:
>>>>> As an integrated GPU, MTL does not have local memory and
>>>>> HAS_LMEM() returns false.  However the platform's stolen memory
>>>>> is presented via BAR2 (i.e., the BAR we traditionally consider
>>>>> to be the LMEM BAR) and should be managed by the driver the same
>>>>> way that local memory is on dgpu platforms (which includes
>>>>> setting the "lmem" bit on page table entries).  We use the term
>>>>> "local stolen memory" to refer to this model.
>>>>>
>>>>> Cc: Matt Roper <matthew.d.roper@intel.com>
>>>>> Cc: Lucas De Marchi <lucas.demarchi@intel.com>
>>>>>
>>>>> Signed-off-by: CQ Tang <cq.tang@intel.com>
>>>>> Signed-off-by: Aravind Iddamsetty <aravind.iddamsetty@intel.com>
>>>>> Original-author: CQ Tang
>>>>> ---
>>>>> drivers/gpu/drm/i915/gem/i915_gem_stolen.c | 113 +++++++++++++++++----
>>>>> drivers/gpu/drm/i915/gt/intel_ggtt.c       |   2 +-
>>>>> drivers/gpu/drm/i915/i915_drv.h            |   3 +
>>>>> 3 files changed, 100 insertions(+), 18 deletions(-)
>>>>>
>>>>> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
>>>>> b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
>>>>> index acc561c0f0aa..bad5250fb764 100644
>>>>> --- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
>>>>> +++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
>>>>> @@ -77,6 +77,19 @@ void i915_gem_stolen_remove_node(struct
>>>>> drm_i915_private *i915,
>>>>>     mutex_unlock(&i915->mm.stolen_lock);
>>>>> }
>>>>>
>>>>> +static bool is_dsm_invalid(struct drm_i915_private *i915, struct
>>>>> resource *dsm)
>>>>> +{
>>>>> +    if (!HAS_BAR2_SMEM_STOLEN(i915)) {
>>>>
>>>> I called a similar function as is_dsm_valid() in
>>>> https://patchwork.freedesktop.org/series/108620/
>>>>
>>>> sounds weird  with "invalid" and the double negation on return early
>>>> style.
>>
>> sure, will change it hope i can use that from your patch.
> 
> that patch is now pushed, so now you can reuse it.
Thanks for the info and help.

Aravind.
> 
> Lucas De Marchi