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Subject: Re: [PATCH 5/5] powerpc/powernv: TCE invalidation for PHB3
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Gavin Shan <shangw@linux.vnet.ibm.com>
Date: Wed, 24 Apr 2013 01:25:08 +1000
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On Tue, 2013-04-23 at 19:03 +0800, Gavin Shan wrote:
>          * of flags if that becomes the case
>          */
>         if (tbl->it_type & TCE_PCI_SWINV_CREATE)
> -               pnv_tce_invalidate(tbl, tces, tcep - 1);
> +               phb->dma_tce_invalidate(tbl, tces, tcep - 1);
>  
>         return 0;
>  }

TCE invalidate is very performance sensitive, we might be better off
doing the if (ioda_type == PNV_PHB_IODA1) ... else ... here (which
the CPU can generally predict) rather than a function pointer call
which can be more tricky.

Cheers,
Ben.