From: Thomas Hellstrom (VMware) <thomas...@shipmail.org>

Clean up and fix dma mode selection. We remove an unused mode, a largely
unused module option and finally add a check to enable dma coherent memory
in those cases streaming dma mappings are undesired or won't work.

Note that this series is intended to be applied on top of
git://people.freedesktop.org/~thomash/linux branch vmwgfx-next

meaning that the vmw_dma_select mode function would, after applying the patches
look like

static int vmw_dma_select_mode(struct vmw_private *dev_priv)
{
        static const char *names[vmw_dma_map_max] = {
                [vmw_dma_alloc_coherent] = "Using coherent TTM pages.",
                [vmw_dma_map_populate] = "Caching DMA mappings.",
                [vmw_dma_map_bind] = "Giving up DMA mappings early."};

        /*
         * dma_max_mapping_size() != SIZE_MAX means something is going
         * on in the dma layer that the dma_map_bind or dma_map_populate modes
         * are not working well with, or haven't been tested with.
         * This typically happens when the SWIOTLB is active. Fall back to
         * coherent memory in those cases.
         */
        if (dma_max_mapping_size(dev_priv->dev->dev) != SIZE_MAX ||
            vmw_force_coherent)
                dev_priv->map_mode = vmw_dma_alloc_coherent;
        else if (vmw_restrict_iommu)
                dev_priv->map_mode = vmw_dma_map_bind;
        else
                dev_priv->map_mode = vmw_dma_map_populate;

        if (!IS_ENABLED(CONFIG_DRM_TTM_DMA_PAGE_POOL) &&
            (dev_priv->map_mode == vmw_dma_alloc_coherent))
                return -EINVAL;

        DRM_INFO("DMA map mode: %s\n", names[dev_priv->map_mode]);
        return 0;
}

Cc: Christoph Hellwig <h...@infradead.org>
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Reply via email to