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Subject: RE: AW: PowerPC PCI DMA issues (prefetch/coherency?)
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Pravin Bathija <pbathija@amcc.com>
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Date: Fri, 11 Sep 2009 15:40:21 +1000
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Cc: Andrea Zypchen <azypchen@intldata.ca>, lebon@lebon.org.ua,
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On Thu, 2009-09-10 at 22:35 -0700, Pravin Bathija wrote:
> Thanks Stefan. The whole intention of the patch/hack (or whatever one
> might call it :) ) was to avoid rogue drivers from setting
> pci_cache_line_size to non-zero value even though the underlying
> hardware doesn't support MRM calls. Nonetheless this approach works
> only if the drivers use the kernel API for PCI config space access
> provided by the powerpc platform driver.
> 
Do you know many drivers that do config space accesses without using
the config space accessors ?

Such drivers should be banned to oblivion.

Cheers,
Ben.