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Subject: Re: [PATCH 2/3] iommu/ipmmu-vmsa: Increase maximum micro-TLBS to 48
To: Magnus Damm <magnus.damm@gmail.com>, iommu@lists.linux-foundation.org
References: <20160607033918.28687.98260.sendpatchset@little-apple>
 <20160607033936.28687.78365.sendpatchset@little-apple>
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From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
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Date: Tue, 7 Jun 2016 13:59:56 +0300
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Hello.

On 6/7/2016 6:39 AM, Magnus Damm wrote:

> From: Magnus Damm <damm+renesas@opensource.se>
>
> Bump up the maximum numbers of micro-TLBS to 48.
>
> Each IPMMU device instance get micro-TLB assignment via
> the "iommus" property in DT. Older SoCs tend to use a
> maximum number of 32 micro-TLBd per IPMMU instance however

    Micro-TLBs?

> newer SoCs such as r8a7796 make use of up to 48 micro-TLBs.
>
> At this point no SoC specific handling is done to validate
> the maximum number of micro-TLBs, and because of that the
> DT information is assumed to be within correct range for
> each particular SoC.
>
> If needed in the future SoC specific feature flags can be
> added to handle the maximum number of micro-TLBs without
> requiring DT changes, however at this point this does not
> seem necessary.
>
> Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
[...]

MBR, Sergei