Re: [PATCH] iommu/sun50i: Allow page sizes between 4K and 1M

From: Robin Murphy
Date: Mon Sep 11 2023 - 23:00:12 EST


On 2023-09-11 20:29, Jernej Škrabec wrote:
On Monday, September 11, 2023 9:06:12 PM CEST Robin Murphy wrote:
On 2023-09-11 20:02, Jernej Skrabec wrote:
While peripheral supports only 4K page sizes, we can easily emulate
support for bigger page sizes, up to 1M. This is done by making multiple
entries in map function or clearing multiple entries in unmap.

No, it's done by converting over to the {map,unmap}_pages ops. There's
no need to resurrect this horrible bodge.

Missed those, thanks! In any case, logic to implement those isn't that
different than here.

Indeed, if anything it should be even simpler since you don't need to worry about specific sizes at all - any tricky boundary you don't want to iterate through, just return short at that point and let the core call you back again with the remainder.

(In fact this reminds me one of the low-priority cleanup jobs outstanding was to trivially convert all the remaining drivers and retire the old interfaces altogether)

Cheers,
Robin.