Re: [PATCH] iommu/rockchip: Perform a reset on shutdown
From: Joerg Roedel
Date: Thu Mar 15 2018 - 10:12:18 EST
On Tue, Feb 20, 2018 at 08:25:04PM +0000, Marc Zyngier wrote:
> Trying to do a kexec whilst the iommus are still on is proving to be
> a challenging exercise. It is terribly unsafe, as we're reusing the
> memory allocated for the page tables, leading to a likely crash.
>
> Let's implement a shutdown method that will at least try to stop
> DMA from going crazy behind our back. Note that we need to be
> extra cautious when doing so, as the IOMMU may not be clocked
> if controlled by a another master, as typical on Rockchip system.
>
> Suggested-by: Robin Murphy <robin.murphy@xxxxxxx>
> Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Applied, thanks.