[PATCH] drm/amdgpu/sriov: For sriov runtime, use kiq to do invalidate tlb

[Christian König]

Am 14.08.2018 um 09:46 schrieb Emily Deng:
> To avoid the tlb flush not interrupted by world switch, use kiq and one
> command to do tlb invalidate.

Well NAK, this just duplicates the TLB handling and moves it outside of 
the GMC code.

Instead just lower the timeout and suppress the warning when SRIOV is 
active.

Christian.

>
> SWDEV-161497
>
> Signed-off-by: Emily Deng <Emily.Deng at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c | 50 ++++++++++++++++++++++++++++++++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h |  2 ++
>   drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c    |  5 ++++
>   3 files changed, 57 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> index 21adb1b6..aa6ddcc 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> @@ -233,6 +233,56 @@ void amdgpu_virt_kiq_wreg(struct amdgpu_device *adev, uint32_t reg, uint32_t v)
>   	pr_err("failed to write reg:%x\n", reg);
>   }
>   
> +void amdgpu_virt_kiq_invalidate_tlb(struct amdgpu_device *adev, struct amdgpu_vmhub *hub,
> +		unsigned eng, u32 req, uint32_t vmid)
> +{
> +	signed long r, cnt = 0;
> +	unsigned long flags;
> +	uint32_t seq;
> +	struct amdgpu_kiq *kiq = &adev->gfx.kiq;
> +	struct amdgpu_ring *ring = &kiq->ring;
> +
> +	BUG_ON(!ring->funcs->emit_reg_write_reg_wait);
> +
> +	spin_lock_irqsave(&kiq->ring_lock, flags);
> +	amdgpu_ring_alloc(ring, 32);
> +	amdgpu_ring_emit_reg_write_reg_wait(ring, hub->vm_inv_eng0_req + eng,
> +					    hub->vm_inv_eng0_ack + eng,
> +					    req, 1 << vmid);
> +	amdgpu_fence_emit_polling(ring, &seq);
> +	amdgpu_ring_commit(ring);
> +	spin_unlock_irqrestore(&kiq->ring_lock, flags);
> +
> +	r = amdgpu_fence_wait_polling(ring, seq, MAX_KIQ_REG_WAIT);
> +
> +	/* don't wait anymore for gpu reset case because this way may
> +	 * block gpu_recover() routine forever, e.g. this virt_kiq_rreg
> +	 * is triggered in TTM and ttm_bo_lock_delayed_workqueue() will
> +	 * never return if we keep waiting in virt_kiq_rreg, which cause
> +	 * gpu_recover() hang there.
> +	 *
> +	 * also don't wait anymore for IRQ context
> +	 * */
> +	if (r < 1 && (adev->in_gpu_reset || in_interrupt()))
> +		goto failed_kiq;
> +
> +	if (in_interrupt())
> +		might_sleep();
> +
> +	while (r < 1 && cnt++ < MAX_KIQ_REG_TRY) {
> +		msleep(MAX_KIQ_REG_BAILOUT_INTERVAL);
> +		r = amdgpu_fence_wait_polling(ring, seq, MAX_KIQ_REG_WAIT);
> +	}
> +
> +	if (cnt > MAX_KIQ_REG_TRY)
> +		goto failed_kiq;
> +
> +	return;
> +
> +failed_kiq:
> +	pr_err("failed to invalidate tlb with kiq\n");
> +}
> +
>   /**
>    * amdgpu_virt_request_full_gpu() - request full gpu access
>    * @amdgpu:	amdgpu device.
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h
> index 880ac11..a2e3c78 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h
> @@ -288,6 +288,8 @@ void amdgpu_free_static_csa(struct amdgpu_device *adev);
>   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);
> +void amdgpu_virt_kiq_invalidate_tlb(struct amdgpu_device *adev, struct amdgpu_vmhub *hub,
> +		unsigned eng, u32 req, uint32_t vmid);
>   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);
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> index ed467de..6a886d9 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> @@ -339,6 +339,11 @@ static void gmc_v9_0_flush_gpu_tlb(struct amdgpu_device *adev,
>   		struct amdgpu_vmhub *hub = &adev->vmhub[i];
>   		u32 tmp = gmc_v9_0_get_invalidate_req(vmid);
>   
> +		if (amdgpu_sriov_vf(adev) && amdgpu_sriov_runtime(adev)) {
> +			amdgpu_virt_kiq_invalidate_tlb(adev, hub, eng, tmp, vmid);
> +			continue;
> +		}
> +
>   		WREG32_NO_KIQ(hub->vm_inv_eng0_req + eng, tmp);
>   
>   		/* Busy wait for ACK.*/