From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Russell King <rmk@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>,
James Bottomley <James.Bottomley@HansenPartnership.com>,
linux-arch@vger.kernel.org
Subject: Re: [RFC PATCH 2/4] pio-mapping: Add ARM support for the PIO mapping API
Date: Thu, 18 Feb 2010 07:39:39 +1100 [thread overview]
Message-ID: <1266439179.16346.287.camel@pasglop> (raw)
In-Reply-To: <20100217200445.GA29249@flint.arm.linux.org.uk>
On Wed, 2010-02-17 at 20:04 +0000, Russell King wrote:
>
> That would be fine if we weren't already using PG_arch_1 for delaying
> D-cache flushes for pages which aren't mapped, in the same way that
> Sparc64 does.
Interesting. Maybe we need more arch bits in there :-)
> That doesn't cover this case though - the problem is not I/D cache
> coherency - the problem has manifested itself as data corruption when
> userspace reads the page.
Yup, let's stick to the other thread. I still don't see why a PIO
mapping API is needed, from what I've read so far, it's a case of
mis-using the existing DMA API that could be fixed at the driver level.
No ?
Cheers,
Ben.
next prev parent reply other threads:[~2010-02-17 20:44 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-05 16:31 [RFC PATCH 0/4] PIO drivers and cache coherency Catalin Marinas
2010-02-05 16:31 ` [RFC PATCH 1/4] pio-mapping: Add generic support for PIO mapping API Catalin Marinas
2010-02-05 16:31 ` [RFC PATCH 2/4] pio-mapping: Add ARM support for the " Catalin Marinas
2010-02-05 16:43 ` James Bottomley
2010-02-05 17:20 ` Catalin Marinas
2010-02-05 17:36 ` James Bottomley
2010-02-05 18:02 ` Catalin Marinas
2010-02-08 16:10 ` Catalin Marinas
2010-02-08 16:54 ` Russell King
2010-02-08 17:20 ` James Bottomley
2010-02-08 17:33 ` Russell King
2010-02-08 19:07 ` James Bottomley
2010-02-08 18:02 ` [RFC PATCH 2/4] pio-mapping: Add ARM support for the PIOmapping API Catalin Marinas
2010-02-08 19:09 ` James Bottomley
2010-02-08 17:14 ` [RFC PATCH 2/4] pio-mapping: Add ARM support for the PIO mapping API James Bottomley
2010-02-09 18:03 ` Catalin Marinas
2010-02-17 9:11 ` Benjamin Herrenschmidt
2010-02-17 20:04 ` Russell King
2010-02-17 20:39 ` Benjamin Herrenschmidt [this message]
2010-02-05 16:32 ` [RFC PATCH 3/4] pio-mapping: Use the PIO mapping API in libata-sff.c Catalin Marinas
2010-02-05 16:32 ` [RFC PATCH 4/4] pio-mapping: Use the PIO mapping API in the ISP1760 HCD driver Catalin Marinas
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