[V3 05/11] drm/amdgpu/virt: add high level interfaces for virt

[Yu, Xiangliang]

> This patch is not derived from my work (amd-sriov-4.3/4.6), please don't add
> my "signed-off-by: Monk Liu " line on it, Seems you add an upper layer
> interface to invoke on gpu_request/release routines, And I will also take role
> in the reviewing of it:
> 
> +		adev->virt.caps &= ~AMDGPU_SRIOV_CAPS_RUNTIME;
> +		return virt->ops->req_full_gpu(adev, init);
> 
> [ml]One nitpick , you need place " adev->virt.caps &=
> ~AMDGPU_SRIOV_CAPS_RUNTIME;" in the second line,

I think it make more clear as it is not runtime when entering full access mode.

> 
> +		r = virt->ops->rel_full_gpu(adev, init);
> +		adev->virt.caps |= AMDGPU_SRIOV_CAPS_RUNTIME;
> 
> [ml] what about rel_full_gpu() failed ?  and if rel_full_gpu is designed not
> allowed to fail then you should type it as non-return function. ( I remember
> in my first initial implementation on rel_gpu function it is is non-return
> function)

I think it is more flexible, we can handle error according to return result.

> 
> 
> +		adev->virt.caps &= ~AMDGPU_SRIOV_CAPS_RUNTIME;
> +		return virt->ops->reset_gpu(adev);
> +	}
> 
> [ML] " adev->virt.caps &= ~AMDGPU_SRIOV_CAPS_RUNTIME"  should be
> put to the second line as well, like:
> 
> r = virt-ops->reset_gpu(adev);
> If (!r)
>     adev->virt.caps &= ~AMDGPU_SRIOV_CAPS_RUNTIME; else
>     BUG(); /* we shouldn't fail in requesting GPU_RESET, check hypervisor
> please */ return r;

I think we can't hang out VM so rudely, need to print out error message and do error handling to enhance the process later.

> 
> BR Monk
> 
> -----Original Message-----
> From: Xiangliang Yu [mailto:Xiangliang.Yu at amd.com]
> Sent: Wednesday, January 11, 2017 9:18 PM
> To: amd-gfx at lists.freedesktop.org
> Cc: Yu, Xiangliang <Xiangliang.Yu at amd.com>; Liu, Monk
> <Monk.Liu at amd.com>
> Subject: [V3 05/11] drm/amdgpu/virt: add high level interfaces for virt
> 
> Add high level interfaces that is not relate to specific asic. So asic files just
> need to implement the interfaces to support virtualization.
> 
> Signed-off-by: Xiangliang Yu <Xiangliang.Yu at amd.com>
> Signed-off-by: Monk Liu <Monk.Liu at amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c | 57
> ++++++++++++++++++++++++++++++++
> drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h | 14 ++++++++
>  2 files changed, 71 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> index 7861b6b..4e7df8e 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> @@ -80,3 +80,60 @@ void amdgpu_virt_kiq_wreg(struct amdgpu_device
> *adev, uint32_t reg, uint32_t v)
>  		DRM_ERROR("wait for kiq fence error: %ld.\n", r);
>  	fence_put(f);
>  }
> +
> +/**
> + * amdgpu_virt_request_full_gpu() - request full gpu access
> + * @amdgpu:	amdgpu device.
> + * @init:	is driver init time.
> + * When start to init/fini driver, first need to request full gpu access.
> + * Return: Zero if request success, otherwise will return error.
> + */
> +int amdgpu_virt_request_full_gpu(struct amdgpu_device *adev, bool init)
> +{
> +	struct amdgpu_virt *virt = &adev->virt;
> +
> +	if (virt->ops && virt->ops->req_full_gpu) {
> +		adev->virt.caps &= ~AMDGPU_SRIOV_CAPS_RUNTIME;
> +		return virt->ops->req_full_gpu(adev, init);
> +	}
> +
> +	return 0;
> +}
> +
> +/**
> + * amdgpu_virt_release_full_gpu() - release full gpu access
> + * @amdgpu:	amdgpu device.
> + * @init:	is driver init time.
> + * When finishing driver init/fini, need to release full gpu access.
> + * Return: Zero if release success, otherwise will returen error.
> + */
> +int amdgpu_virt_release_full_gpu(struct amdgpu_device *adev, bool init)
> +{
> +	struct amdgpu_virt *virt = &adev->virt;
> +	int r;
> +
> +	if (virt->ops && virt->ops->rel_full_gpu) {
> +		r = virt->ops->rel_full_gpu(adev, init);
> +		adev->virt.caps |= AMDGPU_SRIOV_CAPS_RUNTIME;
> +		return r;
> +	}
> +	return 0;
> +}
> +
> +/**
> + * amdgpu_virt_reset_gpu() - reset gpu
> + * @amdgpu:	amdgpu device.
> + * Send reset command to GPU hypervisor to reset GPU that VM is using
> + * Return: Zero if reset success, otherwise will return error.
> + */
> +int amdgpu_virt_reset_gpu(struct amdgpu_device *adev) {
> +	struct amdgpu_virt *virt = &adev->virt;
> +
> +	if (virt->ops && virt->ops->reset_gpu) {
> +		adev->virt.caps &= ~AMDGPU_SRIOV_CAPS_RUNTIME;
> +		return virt->ops->reset_gpu(adev);
> +	}
> +
> +	return 0;
> +}
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h
> index 2869980..45771b0 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h
> @@ -29,11 +29,22 @@
>  #define AMDGPU_SRIOV_CAPS_IS_VF        (1 << 2) /* this GPU is a virtual
> function */
>  #define AMDGPU_PASSTHROUGH_MODE        (1 << 3) /* thw whole GPU is
> pass through for VM */
>  #define AMDGPU_SRIOV_CAPS_RUNTIME      (1 << 4) /* is out of full access
> mode */
> +
> +/**
> + * struct amdgpu_virt_ops - amdgpu device virt operations  */ struct
> +amdgpu_virt_ops {
> +	int (*req_full_gpu)(struct amdgpu_device *adev, bool init);
> +	int (*rel_full_gpu)(struct amdgpu_device *adev, bool init);
> +	int (*reset_gpu)(struct amdgpu_device *adev); };
> +
>  /* GPU virtualization */
>  struct amdgpu_virt {
>  	uint32_t		caps;
>  	uint32_t		reg_val_offs;
>  	struct mutex		lock;
> +	const struct amdgpu_virt_ops	*ops;
>  };
> 
>  #define amdgpu_sriov_enabled(adev) \
> @@ -63,5 +74,8 @@ static inline bool is_virtual_machine(void)  void
> amdgpu_virt_init_setting(struct amdgpu_device *adev);  uint32_t
> amdgpu_virt_kiq_rreg(struct amdgpu_device *adev, uint32_t reg);  void
> amdgpu_virt_kiq_wreg(struct amdgpu_device *adev, uint32_t reg, uint32_t
> v);
> +int amdgpu_virt_request_full_gpu(struct amdgpu_device *adev, bool
> +init); int amdgpu_virt_release_full_gpu(struct amdgpu_device *adev,
> +bool init); int amdgpu_virt_reset_gpu(struct amdgpu_device *adev);
> 
>  #endif
> --
> 2.7.4