[PATCH v9 4/8] drm/xe: Track number of written dwords from workaround batch buffer emission

[Tvrtko Ursulin]

On 11/07/2025 04:32, Lucas De Marchi wrote:
> On Wed, Jul 09, 2025 at 11:54:51AM +0100, Tvrtko Ursulin wrote:
>> Indirect context setup will need to get to the number of written dwords.
>> Lets add it as an output parameter so it can be accessed from the finish
>> helper regardless of whether code is writing directly or via an shadow
>> buffer.
>>
>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at igalia.com>
>> Cc: Lucas De Marchi <lucas.demarchi at intel.com>
>> ---
>> drivers/gpu/drm/xe/xe_lrc.c | 5 ++++-
>> 1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/xe/xe_lrc.c b/drivers/gpu/drm/xe/xe_lrc.c
>> index 5d5b76f16829..229cfde91799 100644
>> --- a/drivers/gpu/drm/xe/xe_lrc.c
>> +++ b/drivers/gpu/drm/xe/xe_lrc.c
>> @@ -991,6 +991,7 @@ struct bo_setup_state {
>>     /* State: */
>>     u32            *buffer;
>>     u32            *ptr;
>> +    unsigned int        written;
> 
> nit: since everywhere we use "len" for the number of dwords, it would
> probably make more sense here. As well as s/buffer/bounce/ in the
> previous patch... but not critical.

I opted to leave both as is since to me current names read a bit more 
obvious. Especially written. Bounce makes sense but I wanted to make it 
bounce_buffer to look less weird, but then it was long, so left it all.

> Reviewed-by: Lucas De Marchi <lucas.demarchi at intel.com>

Thanks!

Regards,

Tvrtko

> 
> Lucas De Marchi
> 
> 
>> };
>>
>> static int setup_bo(struct bo_setup_state *state)
>> @@ -1023,6 +1024,7 @@ static int setup_bo(struct bo_setup_state *state)
>>             goto fail;
>>
>>         state->ptr += len;
>> +        state->written += len;
>>     }
>>
>>     return 0;
>> @@ -1039,7 +1041,7 @@ static void finish_bo(struct bo_setup_state *state)
>>
>>     xe_map_memcpy_to(gt_to_xe(state->lrc->gt), &state->lrc->bo->vmap,
>>              state->offset, state->buffer,
>> -             (state->ptr - state->buffer) * sizeof(u32));
>> +             state->written * sizeof(u32));
>>     kfree(state->buffer);
>> }
>>
>> @@ -1063,6 +1065,7 @@ static int setup_wa_bb(struct xe_lrc *lrc, 
>> struct xe_hw_engine *hwe)
>>         return ret;
>>
>>     *state.ptr++ = MI_BATCH_BUFFER_END;
>> +    state.written++;
>>
>>     finish_bo(&state);
>>
>> -- 
>> 2.48.0
>>