Re: [RFC 6/8] drm/nouveau: override the WPR2 heap size when SRIOV is supported on Ada

[Danilo Krummrich <dakr@kernel.org>]

On Fri, Nov 22, 2024 at 04:57:10AM -0800, Zhi Wang wrote:
> To support the maximum vGPUs on the device that support SRIOV, a larger
> WPR2 heap size is required. On Ada with SRIOV supported, the size should
> be set to at least 549MB. By setting the WPR2 heap size up to 549MB, the
> scrubber ucode image is required to scrub the FB memory before any other
> ucode image is executed.
> 
> Override the default WPR2 heap size on Ada when SRIOV is supported. Set
> the WPR2 heap size up to 576MB when SRIOV is supported on Ada.

Might be worth to also add a brief note about this in the code.

> 
> Cc: Milos Tijanic <mtijanic@nvidia.com>
> Signed-off-by: Zhi Wang <zhiw@nvidia.com>
> ---
>  drivers/gpu/drm/nouveau/nvkm/subdev/gsp/ad102.c | 12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/ad102.c b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/ad102.c
> index 3ba67eab08d7..1e403dbd7323 100644
> --- a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/ad102.c
> +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/ad102.c
> @@ -20,6 +20,7 @@
>   * OTHER DEALINGS IN THE SOFTWARE.
>   */
>  
> +#include <core/pci.h>
>  #include <engine/sec2.h>
>  #include "priv.h"
>  
> @@ -58,9 +59,18 @@ ad102_execute_scrubber(struct nvkm_gsp *gsp)
>  static int
>  ad102_gsp_init_fw_heap(struct nvkm_gsp *gsp)
>  {
> +	struct nvkm_subdev *subdev = &gsp->subdev;
> +	struct nvkm_device *device = subdev->device;
> +	struct nvkm_device_pci *device_pci = container_of(device,
> +			typeof(*device_pci), device);
> +	int num_vfs;
>  	int ret;
>  
> -	nvkm_gsp_init_fw_heap(gsp, 0);
> +	num_vfs = pci_sriov_get_totalvfs(device_pci->pdev);
> +	if (!num_vfs)
> +		nvkm_gsp_init_fw_heap(gsp, 0);
> +	else
> +		nvkm_gsp_init_fw_heap(gsp, 576 * SZ_1M);
>  
>  	if (gsp->fb.wpr2.heap.size <= SZ_256M)
>  		return 0;
> -- 
> 2.34.1
>