[PATCH] drm/amdgpu: Adjust logic in amdgpu_device_partner_bandwidth()

[PATCH] drm/amdgpu: Adjust logic in amdgpu_device_partner_bandwidth()

[Alex Deucher]

Use current speed/width on devices which don't support
dynamic PCIe switching.

Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3289
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index e72e774d17e6a..f0011dac589d2 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -5946,13 +5946,18 @@ static void amdgpu_device_partner_bandwidth(struct amdgpu_device *adev,
 	*speed = PCI_SPEED_UNKNOWN;
 	*width = PCIE_LNK_WIDTH_UNKNOWN;
 
-	while ((parent = pci_upstream_bridge(parent))) {
-		/* skip upstream/downstream switches internal to dGPU*/
-		if (parent->vendor == PCI_VENDOR_ID_ATI)
-			continue;
-		*speed = pcie_get_speed_cap(parent);
-		*width = pcie_get_width_cap(parent);
-		break;
+	if (amdgpu_device_pcie_dynamic_switching_supported(adev)) {
+		while ((parent = pci_upstream_bridge(parent))) {
+			/* skip upstream/downstream switches internal to dGPU*/
+			if (parent->vendor == PCI_VENDOR_ID_ATI)
+				continue;
+			*speed = pcie_get_speed_cap(parent);
+			*width = pcie_get_width_cap(parent);
+			break;
+		}
+	} else {
+		/* use the current speeds rather than max if switching is not supported */
+		pcie_bandwidth_available(adev->pdev, NULL, speed, width);
 	}
 }
 
-- 
2.45.0

Re: [PATCH] drm/amdgpu: Adjust logic in amdgpu_device_partner_bandwidth()

[Alex Deucher]

Ping?

On Thu, May 16, 2024 at 11:42 AM Alex Deucher <alexander.deucher@amd.com> wrote:
>
> Use current speed/width on devices which don't support
> dynamic PCIe switching.
>
> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3289
> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 19 ++++++++++++-------
>  1 file changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index e72e774d17e6a..f0011dac589d2 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -5946,13 +5946,18 @@ static void amdgpu_device_partner_bandwidth(struct amdgpu_device *adev,
>         *speed = PCI_SPEED_UNKNOWN;
>         *width = PCIE_LNK_WIDTH_UNKNOWN;
>
> -       while ((parent = pci_upstream_bridge(parent))) {
> -               /* skip upstream/downstream switches internal to dGPU*/
> -               if (parent->vendor == PCI_VENDOR_ID_ATI)
> -                       continue;
> -               *speed = pcie_get_speed_cap(parent);
> -               *width = pcie_get_width_cap(parent);
> -               break;
> +       if (amdgpu_device_pcie_dynamic_switching_supported(adev)) {
> +               while ((parent = pci_upstream_bridge(parent))) {
> +                       /* skip upstream/downstream switches internal to dGPU*/
> +                       if (parent->vendor == PCI_VENDOR_ID_ATI)
> +                               continue;
> +                       *speed = pcie_get_speed_cap(parent);
> +                       *width = pcie_get_width_cap(parent);
> +                       break;
> +               }
> +       } else {
> +               /* use the current speeds rather than max if switching is not supported */
> +               pcie_bandwidth_available(adev->pdev, NULL, speed, width);
>         }
>  }
>
> --
> 2.45.0
>

Re: [PATCH] drm/amdgpu: Adjust logic in amdgpu_device_partner_bandwidth()

[Christian König]

Am 16.05.24 um 17:05 schrieb Alex Deucher:
> Use current speed/width on devices which don't support
> dynamic PCIe switching.
>
> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3289
> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

Acked-by: Christian König <christian.koenig@amd.com>

> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 19 ++++++++++++-------
>   1 file changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index e72e774d17e6a..f0011dac589d2 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -5946,13 +5946,18 @@ static void amdgpu_device_partner_bandwidth(struct amdgpu_device *adev,
>   	*speed = PCI_SPEED_UNKNOWN;
>   	*width = PCIE_LNK_WIDTH_UNKNOWN;
>   
> -	while ((parent = pci_upstream_bridge(parent))) {
> -		/* skip upstream/downstream switches internal to dGPU*/
> -		if (parent->vendor == PCI_VENDOR_ID_ATI)
> -			continue;
> -		*speed = pcie_get_speed_cap(parent);
> -		*width = pcie_get_width_cap(parent);
> -		break;
> +	if (amdgpu_device_pcie_dynamic_switching_supported(adev)) {
> +		while ((parent = pci_upstream_bridge(parent))) {
> +			/* skip upstream/downstream switches internal to dGPU*/
> +			if (parent->vendor == PCI_VENDOR_ID_ATI)
> +				continue;
> +			*speed = pcie_get_speed_cap(parent);
> +			*width = pcie_get_width_cap(parent);
> +			break;
> +		}
> +	} else {
> +		/* use the current speeds rather than max if switching is not supported */
> +		pcie_bandwidth_available(adev->pdev, NULL, speed, width);
>   	}
>   }
>