From: will.deacon@arm•com (Will Deacon)
To: linux-arm-kernel@lists•infradead.org
Subject: [RFC PATCH 2/7] dma-mapping: replace set_arch_dma_coherent_ops with arch_setup_dma_ops
Date: Mon, 1 Sep 2014 17:20:46 +0100 [thread overview]
Message-ID: <20140901162046.GJ24594@arm.com> (raw)
In-Reply-To: <3185781.KdfsMO5OZS@wuerfel>
On Mon, Sep 01, 2014 at 03:27:30PM +0100, Arnd Bergmann wrote:
> On Friday 29 August 2014 16:54:25 Will Deacon wrote:
> > set_arch_dma_coherent_ops is called from of_dma_configure in order to
> > swizzle the architectural dma-mapping functions over to a cache-coherent
> > implementation. This is currently implemented only for ARM.
> >
> > In anticipation of re-using this mechanism for IOMMU-backed dma-mapping
> > ops too, this patch replaces the function with a broader
> > arch_setup_dma_ops callback which is also responsible for setting the
> > DMA mask and offset as well as selecting the correct mapping functions.
> >
> > A further advantage of this split is that it nicely isolates the
> > of-specific code from the dma-mapping code, allowing potential reuse by
> > other buses (e.g. PCI) in the future.
> >
> > Signed-off-by: Will Deacon <will.deacon@arm•com>
>
> Looks good, just one tiny comment
>
> > ---
> > arch/arm/include/asm/dma-mapping.h | 20 ++++++++++++++----
> > drivers/of/platform.c | 42 ++++++++++----------------------------
> > include/linux/dma-mapping.h | 8 +++-----
> > 3 files changed, 30 insertions(+), 40 deletions(-)
> >
> > diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
> > index c45b61a4b4a5..936125ef3f3f 100644
> > --- a/arch/arm/include/asm/dma-mapping.h
> > +++ b/arch/arm/include/asm/dma-mapping.h
> > @@ -121,12 +121,24 @@ static inline unsigned long dma_max_pfn(struct device *dev)
> > }
> > #define dma_max_pfn(dev) dma_max_pfn(dev)
> >
> > -static inline int set_arch_dma_coherent_ops(struct device *dev)
> > +static inline void arch_setup_dma_ops(struct device *dev, u64 mask,
> > + unsigned long offset, bool coherent)
> > {
> > - set_dma_ops(dev, &arm_coherent_dma_ops);
> > - return 0;
> > + dev->coherent_dma_mask = mask;
> > +
> > + /*
> > + * Set dma_mask to coherent_dma_mask by default if the architecture
> > + * code has not set it.
> > + */
> > + if (!dev->dma_mask)
> > + dev->dma_mask = &dev->coherent_dma_mask;
> > +
>
> We are in architecture specific code here, and we know that this
> architecture has not set up the dev->dma_mask pointer, so we can
> remove the 'if (!dev->dma_mask)'
Good point; I'll fix it.
Thanks,
Will
next prev parent reply other threads:[~2014-09-01 16:20 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-29 15:54 [RFC PATCH 0/7] Introduce automatic DMA configuration for IOMMU masters Will Deacon
2014-08-29 15:54 ` [RFC PATCH 1/7] iommu: provide early initialisation hook for IOMMU drivers Will Deacon
2014-09-01 7:52 ` Thierry Reding
2014-09-01 14:31 ` Arnd Bergmann
2014-09-01 16:36 ` Will Deacon
2014-09-02 6:56 ` Laurent Pinchart
2014-09-02 14:47 ` Varun Sethi
2014-09-02 15:04 ` Arnd Bergmann
2014-08-29 15:54 ` [RFC PATCH 2/7] dma-mapping: replace set_arch_dma_coherent_ops with arch_setup_dma_ops Will Deacon
2014-09-01 14:27 ` Arnd Bergmann
2014-09-01 16:20 ` Will Deacon [this message]
2014-08-29 15:54 ` [RFC PATCH 3/7] iommu: add new iommu_ops callback for adding a device with a set of IDs Will Deacon
2014-09-01 8:13 ` Thierry Reding
2014-09-01 14:39 ` Arnd Bergmann
2014-09-01 16:34 ` Will Deacon
2014-09-01 17:18 ` Arnd Bergmann
2014-08-29 15:54 ` [RFC PATCH 4/7] iommu: provide helper function to configure an IOMMU for an of master Will Deacon
2014-09-01 8:29 ` Thierry Reding
2014-09-01 14:46 ` Arnd Bergmann
2014-09-01 16:40 ` Will Deacon
2014-09-01 20:18 ` Arnd Bergmann
2014-09-02 10:03 ` Will Deacon
2014-09-02 12:15 ` Arnd Bergmann
2014-09-02 13:05 ` Will Deacon
2014-09-02 14:01 ` Arnd Bergmann
2014-09-02 20:59 ` jroedel at suse.de
2014-09-03 9:45 ` Will Deacon
2014-09-02 15:03 ` Varun Sethi
2014-09-02 15:08 ` Arnd Bergmann
2014-09-02 10:23 ` Laurent Pinchart
2014-09-02 10:51 ` Laurent Pinchart
2014-09-02 11:03 ` Will Deacon
2014-09-02 19:08 ` Laurent Pinchart
2014-09-02 14:55 ` Varun Sethi
2014-08-29 15:54 ` [RFC PATCH 5/7] dma-mapping: detect and configure IOMMU in of_dma_configure Will Deacon
2014-09-01 14:53 ` Arnd Bergmann
2014-08-29 15:54 ` [RFC PATCH 6/7] arm: call iommu_init before of_platform_populate Will Deacon
2014-08-29 15:54 ` [RFC PATCH 7/7] arm: dma-mapping: plumb our iommu mapping ops into arch_setup_dma_ops Will Deacon
2014-09-02 6:26 ` [RFC PATCH 0/7] Introduce automatic DMA configuration for IOMMU masters Marek Szyprowski
2014-09-02 8:31 ` Will Deacon
2014-09-02 8:48 ` Marek Szyprowski
2014-09-02 8:56 ` Arnd Bergmann
2014-09-02 10:42 ` Marek Szyprowski
2014-09-02 10:57 ` Will Deacon
2014-09-02 12:24 ` Marek Szyprowski
2014-09-02 12:43 ` Arnd Bergmann
2014-09-02 21:50 ` Laurent Pinchart
2014-09-02 12:22 ` Arnd Bergmann
2014-09-02 12:30 ` Marek Szyprowski
2014-09-02 12:46 ` Arnd Bergmann
2014-09-02 13:11 ` Marek Szyprowski
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