[RESEND PATCHv5] iommu/mediatek: check 4GB mode by reading infracfg

[Joerg Roedel]

On Fri, Sep 04, 2020 at 06:40:38PM +0800, Miles Chen wrote:
> In previous discussion [1] and [2], we found that it is risky to
> use max_pfn or totalram_pages to tell if 4GB mode is enabled.
> 
> Check 4GB mode by reading infracfg register, remove the usage
> of the un-exported symbol max_pfn.
> 
> This is a step towards building mtk_iommu as a kernel module.
> 
> [1] https://lore.kernel.org/lkml/20200603161132.2441-1-miles.chen@mediatek.com/
> [2] https://lore.kernel.org/lkml/20200604080120.2628-1-miles.chen@mediatek.com/
> [3] https://lore.kernel.org/lkml/20200715205120.GA778876@bogus/

Applied, thanks.