Commit 4c08f019 authored by Zack Rusin's avatar Zack Rusin
Browse files

drm/vmwgfx: Enable DMA mappings with SEV 



Enable DMA mappings in vmwgfx after TTM has been fixed in commit
3bf3710e ("drm/ttm: Add a generic TTM memcpy move for page-based iomem")

This enables full guest-backed memory support and in particular allows
usage of screen targets as the presentation mechanism.

Signed-off-by: default avatarZack Rusin <zack.rusin@broadcom.com>
Reported-by: default avatarYe Li <ye.li@broadcom.com>
Tested-by: default avatarYe Li <ye.li@broadcom.com>
Fixes: 3b0d6458 ("drm/vmwgfx: Refuse DMA operation when SEV encryption is active")
Cc: Broadcom internal kernel review list <bcm-kernel-feedback-list@broadcom.com>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v6.6+
Reviewed-by: default avatarMartin Krastev <martin.krastev@broadcom.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240408022802.358641-1-zack.rusin@broadcom.com
parent 3eadd887

drivers/gpu/drm/vmwgfx/vmwgfx_drv.c

+6 −5
Original line number Diff line number Diff line
@@ -666,11 +666,12 @@ static int vmw_dma_select_mode(struct vmw_private *dev_priv) 
		[vmw_dma_map_populate] = "Caching DMA mappings.",

		[vmw_dma_map_bind] = "Giving up DMA mappings early."};



	/* TTM currently doesn't fully support SEV encryption. */

	if (cc_platform_has(CC_ATTR_MEM_ENCRYPT))

		return -EINVAL;



	if (vmw_force_coherent)

	/*

	 * When running with SEV we always want dma mappings, because

	 * otherwise ttm tt pool pages will bounce through swiotlb running

	 * out of available space.

	 */

	if (vmw_force_coherent || cc_platform_has(CC_ATTR_MEM_ENCRYPT))

		dev_priv->map_mode = vmw_dma_alloc_coherent;

	else if (vmw_restrict_iommu)

		dev_priv->map_mode = vmw_dma_map_bind;