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SubjectRe: [PATCH v11 17/27] iommu/exynos: remove calls to Runtime PM API functions
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On Wed, Mar 19, 2014 at 6:12 AM, Tomasz Figa <t.figa@samsung.com> wrote:
...
> No. Proper Linux drivers must support deferred probing mechanism and there
> should be no assumptions about probing orders. Using other initcall level
> than module_initcall for particular drivers is strongly discouraged.

That's true for "end-point" devices. It's not true for
"infrastructure": Memory, CPU, DMA, Interrupt handling, etc. Those
need to be in place before "normal" drivers get called. This SysMMU
driver provides DMA services for "normal" device drivers. Or do I see
that wrong?

thanks,
grant

ps. I've written IOMMU support for four different IOMMUs on three
operating systems (See drivers/parisc for two linux examples). But I
still feel like I at best have 80% understanding of how this one is
organized/works. Abstract descriptions and convoluted code have been
handicapping me (and lack of time to dig further).


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