Re: [RFC PATCH] iommu/dma: Allow drivers to reserve an iova range

Joerg Roedel
2020-02-19T09:46:14Z

On Fri, Feb 14, 2020 at 02:58:16PM -0800, Isaac J. Manjarres wrote:
> From: Liam Mark <lmark@codeaurora.org>
>
> Some devices have a memory map which contains gaps or holes.
> In order for the device to have as much IOVA space as possible,
> allow its driver to inform the DMA-IOMMU layer that it should
> not allocate addresses from these holes.
>
> Change-Id: I15bd1d313d889c2572d0eb2adecf6bebde3267f7
> Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>

Ideally this is something put into the IOMMU firmware table by the
platform firmware. If its not there, a quirk is the best way to handle
this.

Regards,

Joerg