[PATCH] drm/amdgpu: Check resize bar register when system uses large bar

[Christian König]

Am 19.12.23 um 06:58 schrieb Ma Jun:
> Print a warnning message if the system can't access
> the resize bar register when using large bar.

Well pretty clear NAK, we have embedded use cases where this would 
trigger an incorrect warning.

What should that be good for in the first place?

Regards,
Christian.

>
> Signed-off-by: Ma Jun <Jun.Ma2 at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 10 +++++++++-
>   1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 4b694696930e..e7aedb4bd66e 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -1417,6 +1417,12 @@ void amdgpu_device_wb_free(struct amdgpu_device *adev, u32 wb)
>   		__clear_bit(wb, adev->wb.used);
>   }
>   
> +static inline void amdgpu_find_rb_register(struct amdgpu_device *adev)
> +{
> +	if (!pci_find_ext_capability(adev->pdev, PCI_EXT_CAP_ID_REBAR))
> +		DRM_WARN("System can't access the resize bar register,please check!!\n");
> +}
> +
>   /**
>    * amdgpu_device_resize_fb_bar - try to resize FB BAR
>    *
> @@ -1444,8 +1450,10 @@ int amdgpu_device_resize_fb_bar(struct amdgpu_device *adev)
>   
>   	/* skip if the bios has already enabled large BAR */
>   	if (adev->gmc.real_vram_size &&
> -	    (pci_resource_len(adev->pdev, 0) >= adev->gmc.real_vram_size))
> +	    (pci_resource_len(adev->pdev, 0) >= adev->gmc.real_vram_size)) {
> +		amdgpu_find_rb_register(adev);
>   		return 0;
> +	}
>   
>   	/* Check if the root BUS has 64bit memory resources */
>   	root = adev->pdev->bus;