[Intel-xe] [PATCH 1/2] RFC drm/xe: Disable ctb communication

[Riana Tauro]

Hi Bala

Thanks for the review

On 8/23/2023 12:02 PM, Balasubramani Vivekanandan wrote:
> On 23.08.2023 10:39, Riana Tauro wrote:
>> During Runtime suspend, GuC is reset for both D0->D3hot/D3Cold
>> transistions. It is not necessary for GuC to reset for D0 -> D3hot,
>> only enable/disable ctb communication.
>>
>> Modify the existing ct disable function to send a request
>> to disable ct communication if firmware is running.
>> Add a function to disable guc communication.
>>
>> Signed-off-by: Riana Tauro <riana.tauro at intel.com>
>> ---
>>   drivers/gpu/drm/xe/xe_guc.c    | 15 +++++++++++++++
>>   drivers/gpu/drm/xe/xe_guc.h    |  1 +
>>   drivers/gpu/drm/xe/xe_guc_ct.c | 11 ++++++++++-
>>   drivers/gpu/drm/xe/xe_guc_ct.h |  2 +-
>>   4 files changed, 27 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/xe/xe_guc.c b/drivers/gpu/drm/xe/xe_guc.c
>> index 2493c5859948..3e4c00bee6bf 100644
>> --- a/drivers/gpu/drm/xe/xe_guc.c
>> +++ b/drivers/gpu/drm/xe/xe_guc.c
>> @@ -557,6 +557,21 @@ int xe_guc_enable_communication(struct xe_guc *guc)
>>   	return 0;
>>   }
>>   
>> +int xe_guc_disable_communication(struct xe_guc *guc)
>> +{
>> +	int err;
>> +	struct xe_guc_ct *ct = &guc->ct;
>> +
>> +	err = xe_guc_ct_disable(ct);
>> +	if (err)
>> +		return err;
>> +
>> +	/* Check for messages received during/after the CT disable */
>> +	guc_handle_mmio_msg(guc);
>> +
>> +	return 0;
>> +}
>> +
>>   int xe_guc_suspend(struct xe_guc *guc)
>>   {
>>   	int ret;
>> diff --git a/drivers/gpu/drm/xe/xe_guc.h b/drivers/gpu/drm/xe/xe_guc.h
>> index 3addd8fc674a..18cf5d02eea7 100644
>> --- a/drivers/gpu/drm/xe/xe_guc.h
>> +++ b/drivers/gpu/drm/xe/xe_guc.h
>> @@ -18,6 +18,7 @@ int xe_guc_post_load_init(struct xe_guc *guc);
>>   int xe_guc_reset(struct xe_guc *guc);
>>   int xe_guc_upload(struct xe_guc *guc);
>>   int xe_guc_min_load_for_hwconfig(struct xe_guc *guc);
>> +int xe_guc_disable_communication(struct xe_guc *guc);
>>   int xe_guc_enable_communication(struct xe_guc *guc);
>>   int xe_guc_suspend(struct xe_guc *guc);
>>   void xe_guc_notify(struct xe_guc *guc);
>> diff --git a/drivers/gpu/drm/xe/xe_guc_ct.c b/drivers/gpu/drm/xe/xe_guc_ct.c
>> index 59136b6a7c6f..64c2029b2752 100644
>> --- a/drivers/gpu/drm/xe/xe_guc_ct.c
>> +++ b/drivers/gpu/drm/xe/xe_guc_ct.c
>> @@ -21,6 +21,7 @@
>>   #include "xe_map.h"
>>   #include "xe_pm.h"
>>   #include "xe_trace.h"
>> +#include "xe_uc_fw.h"
>>   
>>   /* Used when a CT send wants to block and / or receive data */
>>   struct g2h_fence {
>> @@ -319,15 +320,23 @@ int xe_guc_ct_enable(struct xe_guc_ct *ct)
>>   	return err;
>>   }
>>   
>> -void xe_guc_ct_disable(struct xe_guc_ct *ct)
>> +int xe_guc_ct_disable(struct xe_guc_ct *ct)
>>   {
>> +	struct xe_guc *guc = ct_to_guc(ct);
>> +	int ret = 0;
>> +
>>   	mutex_lock(&ct->lock); /* Serialise dequeue_one_g2h() */
>>   	spin_lock_irq(&ct->fast_lock); /* Serialise CT fast-path */
>>   	ct->enabled = false; /* Finally disable CT communication */
>>   	spin_unlock_irq(&ct->fast_lock);
>>   	mutex_unlock(&ct->lock);
>>   
>> +	if (xe_uc_fw_is_running(&guc->fw))
>> +		ret = guc_ct_control_toggle(ct, false);
> 
> ct->enabled holds incorrect status (false) if guc_ct_control_toggle()
> fails.
> 
Will reorder this and send out a new rev

Thanks
Riana
> Regards,
> Bala
>> +
>>   	xa_destroy(&ct->fence_lookup);
>> +
>> +	return ret;
>>   }
>>   
>>   static bool h2g_has_room(struct xe_guc_ct *ct, u32 cmd_len)
>> diff --git a/drivers/gpu/drm/xe/xe_guc_ct.h b/drivers/gpu/drm/xe/xe_guc_ct.h
>> index f15f8a4857e0..1ad150c19ae3 100644
>> --- a/drivers/gpu/drm/xe/xe_guc_ct.h
>> +++ b/drivers/gpu/drm/xe/xe_guc_ct.h
>> @@ -12,7 +12,7 @@ struct drm_printer;
>>   
>>   int xe_guc_ct_init(struct xe_guc_ct *ct);
>>   int xe_guc_ct_enable(struct xe_guc_ct *ct);
>> -void xe_guc_ct_disable(struct xe_guc_ct *ct);
>> +int xe_guc_ct_disable(struct xe_guc_ct *ct);
>>   void xe_guc_ct_fast_path(struct xe_guc_ct *ct);
>>   
>>   struct xe_guc_ct_snapshot *
>> -- 
>> 2.40.0
>>