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From: arnd@arndb•de (Arnd Bergmann)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH 1/6] Realview PCIX support - add main support module code
Date: Thu, 28 Oct 2010 16:29:46 +0200	[thread overview]
Message-ID: <201010281629.46913.arnd@arndb.de> (raw)
In-Reply-To: <20101028140949.GE3122@n2100.arm.linux.org.uk>

On Thursday 28 October 2010, Russell King - ARM Linux wrote:
> On Wed, Oct 20, 2010 at 11:16:32PM +0200, Arnd Bergmann wrote:
> > > +{
> > > +   u32 mode;
> > > +   u32 config_addr;
> > > +
> > > +   writel(0x000307F7, PCIX_UNIT_BASE + PCI_PERRSTAT); /* clear error bit */
> > > +   writew(0xfb30, PCIX_UNIT_BASE + PCI_STATUS);       /* error bit clear */
> > 
> > I would guess that you need locking here, two drivers might simultaneously be
> > accessing config space on different CPUs, or you might have kernel preemption
> > enabled and get preempted between the register accesses.
> 
> pci config accesses are serialized by a global pci_lock raw spinlock,
> which disables IRQs.

Ok, good. Ignore my comment then.

	Arnd

  reply	other threads:[~2010-10-28 14:29 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-10-20 13:02 [PATCH 0/6] Add PCI support for ARM RealView boards Colin Tuckley
2010-10-20 13:02 ` [PATCH 1/6] Realview PCIX support - add main support module code Colin Tuckley
2010-10-20 21:16   ` Arnd Bergmann
2010-10-21 10:03     ` Colin Tuckley
2010-10-21 12:44       ` Arnd Bergmann
2010-10-28 14:09     ` Russell King - ARM Linux
2010-10-28 14:29       ` Arnd Bergmann [this message]
2010-10-28 14:02   ` Russell King - ARM Linux
2010-10-20 13:02 ` [PATCH 2/6] ARM: enable bridges in pci_common_init Colin Tuckley
2010-10-20 13:03 ` [PATCH 3/6] ARM Realview PCIX map include file changes Colin Tuckley
2010-10-20 21:28   ` Arnd Bergmann
2010-10-20 13:03 ` [PATCH 4/6] ARM Realview PCIX IRQ " Colin Tuckley
2010-10-20 13:03 ` [PATCH 5/6] ARM Realview PCIX board " Colin Tuckley
2010-10-20 13:03 ` [PATCH 6/6] ARM Realview PCIX build " Colin Tuckley
2010-10-20 21:32   ` Arnd Bergmann

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