[PATCH] drm/amdgpu: XGMI pstate switch initial support

[Liu, Shaoyun]

Driver vote low to high pstate switch whenever there is an outstanding
XGMI mapping request. Driver vote high to low pstate when all the
outstanding XGMI mapping is terminated.

Change-Id: I197501f853c47f844055c0e28c0ac00a1ff06607
Signed-off-by: shaoyunl <shaoyun.liu at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h        |  5 +++++
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  5 +++++
 drivers/gpu/drm/amd/amdgpu/amdgpu_object.h |  2 ++
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c     | 26 ++++++++++++++++++++++++++
 drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c   | 16 +++++++++++++++-
 drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.h   |  2 ++
 6 files changed, 55 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 1db1921..c9c24d6 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -932,6 +932,11 @@ struct amdgpu_device {
 	struct work_struct		xgmi_reset_work;
 
 	bool                            in_baco_reset;
+
+	/* counter of mapped memory through xgmi */
+	atomic_t			xgmi_map_counter;
+	struct mutex  			lock_pstate;
+
 };
 
 static inline struct amdgpu_device *amdgpu_ttm_adev(struct ttm_bo_device *bdev)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 2065837..a5af885 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -2018,6 +2018,10 @@ static void amdgpu_device_ip_late_init_func_handler(struct work_struct *work)
 	r = amdgpu_device_enable_mgpu_fan_boost();
 	if (r)
 		DRM_ERROR("enable mgpu fan boost failed (%d).\n", r);
+
+	/*set to low pstate by default */
+	amdgpu_xgmi_set_pstate(adev, 0);
+
 }
 
 static void amdgpu_device_delay_enable_gfx_off(struct work_struct *work)
@@ -2467,6 +2471,7 @@ int amdgpu_device_init(struct amdgpu_device *adev,
 	mutex_init(&adev->virt.vf_errors.lock);
 	hash_init(adev->mn_hash);
 	mutex_init(&adev->lock_reset);
+	mutex_init(&adev->lock_pstate);
 
 	amdgpu_device_check_arguments(adev);
 
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
index 220a6a7..c430e82 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
@@ -72,6 +72,8 @@ struct amdgpu_bo_va {
 
 	/* If the mappings are cleared or filled */
 	bool				cleared;
+
+	bool				is_xgmi;
 };
 
 struct amdgpu_bo {
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index c8f0e4c..3639cf6 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -34,6 +34,7 @@
 #include "amdgpu_trace.h"
 #include "amdgpu_amdkfd.h"
 #include "amdgpu_gmc.h"
+#include "amdgpu_xgmi.h"
 
 /**
  * DOC: GPUVM
@@ -2352,6 +2353,14 @@ int amdgpu_vm_handle_moved(struct amdgpu_device *adev,
 	return 0;
 }
 
+static bool amdgpu_xgmi_same_hive(struct amdgpu_device *adev,
+		struct amdgpu_device *bo_adev)
+{
+	return (adev != bo_adev &&
+		adev->gmc.xgmi.hive_id &&
+		adev->gmc.xgmi.hive_id == bo_adev->gmc.xgmi.hive_id);
+}
+
 /**
  * amdgpu_vm_bo_add - add a bo to a specific vm
  *
@@ -2383,6 +2392,15 @@ struct amdgpu_bo_va *amdgpu_vm_bo_add(struct amdgpu_device *adev,
 	INIT_LIST_HEAD(&bo_va->valids);
 	INIT_LIST_HEAD(&bo_va->invalids);
 
+	if (amdgpu_xgmi_same_hive(adev, amdgpu_ttm_adev(bo->tbo.bdev))) {
+		bo_va->is_xgmi = true;
+		mutex_lock(&adev->lock_pstate);
+		/* Power up XGMI if it can be potentially used */
+		if (atomic_inc_return(&adev->xgmi_map_counter) == 1)
+			amdgpu_xgmi_set_pstate(adev, 1);
+		mutex_unlock(&adev->lock_pstate);
+	}
+
 	return bo_va;
 }
 
@@ -2801,6 +2819,14 @@ void amdgpu_vm_bo_rmv(struct amdgpu_device *adev,
 	}
 
 	dma_fence_put(bo_va->last_pt_update);
+
+	if (bo_va->is_xgmi) {
+		mutex_lock(&adev->lock_pstate);
+		if (atomic_dec_return(&adev->xgmi_map_counter) == 0)
+			amdgpu_xgmi_set_pstate(adev, 0);
+		mutex_unlock(&adev->lock_pstate);
+	}
+
 	kfree(bo_va);
 }
 
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c
index fcc4b05..3368347 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.c
@@ -200,12 +200,26 @@ struct amdgpu_hive_info *amdgpu_get_xgmi_hive(struct amdgpu_device *adev, int lo
 
 	if (lock)
 		mutex_lock(&tmp->hive_lock);
-
+	tmp->pstate = -1;
 	mutex_unlock(&xgmi_mutex);
 
 	return tmp;
 }
 
+int amdgpu_xgmi_set_pstate(struct amdgpu_device *adev, int pstate)
+{
+	int ret = 0;
+	struct amdgpu_hive_info *hive = amdgpu_get_xgmi_hive(adev, 0);
+
+	if (!hive)
+		return 0;
+
+	if (hive->pstate == pstate)
+		return 0;
+	/* Todo : sent the message to SMU for pstate change */
+	return ret;
+}
+
 int amdgpu_xgmi_update_topology(struct amdgpu_hive_info *hive, struct amdgpu_device *adev)
 {
 	int ret = -EINVAL;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.h
index 24a3b03..7e1710fc 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_xgmi.h
@@ -33,11 +33,13 @@ struct amdgpu_hive_info {
 	struct kobject *kobj;
 	struct device_attribute dev_attr;
 	struct amdgpu_device *adev;
+	int pstate; /*0 -- low , 1 -- high , -1 unknown*/
 };
 
 struct amdgpu_hive_info *amdgpu_get_xgmi_hive(struct amdgpu_device *adev, int lock);
 int amdgpu_xgmi_update_topology(struct amdgpu_hive_info *hive, struct amdgpu_device *adev);
 int amdgpu_xgmi_add_device(struct amdgpu_device *adev);
 void amdgpu_xgmi_remove_device(struct amdgpu_device *adev);
+int amdgpu_xgmi_set_pstate(struct amdgpu_device *adev, int pstate);
 
 #endif
-- 
2.7.4