From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752710Ab3KDSjX (ORCPT ); Mon, 4 Nov 2013 13:39:23 -0500 Received: from smtp02.citrix.com ([66.165.176.63]:23961 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750791Ab3KDSjW (ORCPT ); Mon, 4 Nov 2013 13:39:22 -0500 X-IronPort-AV: E=Sophos;i="4.93,634,1378857600"; d="scan'208";a="67843095" Date: Mon, 4 Nov 2013 18:38:05 +0000 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: CC: Konrad Rzeszutek Wilk , , , , Ian Campbell , , Stefano Stabellini Subject: Re: [PATCH v9 01/18] arm: make SWIOTLB available In-Reply-To: Message-ID: References: <1382698313-13161-1-git-send-email-stefano.stabellini@eu.citrix.com> <20131029142023.GE20487@phenom.dumpdata.com> <20131029142626.GQ16735@n2100.arm.linux.org.uk> <20131029180105.GR16735@n2100.arm.linux.org.uk> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 30 Oct 2013, Stefano Stabellini wrote: > On Tue, 29 Oct 2013, Russell King - ARM Linux wrote: > > So... what I'm saying is please fix xgmac to use the DMA API properly > > rather than working around such problems. :) > > OK. > Would the appended patch fix your concerns? ping? > --- > > arm: make SWIOTLB available > > IOMMU_HELPER is needed because SWIOTLB calls iommu_is_span_boundary, > provided by lib/iommu_helper.c. > > Signed-off-by: Stefano Stabellini > Reviewed-by: Konrad Rzeszutek Wilk > > Changes in v9: > - remove uneeded include asm/cacheflush.h; > - just return 0 if !dev->dma_mask in dma_capable. > > --- > arch/arm/Kconfig | 6 ++++++ > arch/arm/include/asm/dma-mapping.h | 33 +++++++++++++++++++++++++++++++++ > 2 files changed, 39 insertions(+), 0 deletions(-) > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > index 1ad6fb6..b08374f 100644 > --- a/arch/arm/Kconfig > +++ b/arch/arm/Kconfig > @@ -1872,6 +1872,12 @@ config CC_STACKPROTECTOR > neutralized via a kernel panic. > This feature requires gcc version 4.2 or above. > > +config SWIOTLB > + def_bool y > + > +config IOMMU_HELPER > + def_bool SWIOTLB > + > config XEN_DOM0 > def_bool y > depends on XEN > diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h > index 5b579b9..1ad2c17 100644 > --- a/arch/arm/include/asm/dma-mapping.h > +++ b/arch/arm/include/asm/dma-mapping.h > @@ -86,6 +86,39 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr) > } > #endif > > +static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) > +{ > + unsigned int offset = paddr & ~PAGE_MASK; > + return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset; > +} > + > +static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr) > +{ > + unsigned int offset = dev_addr & ~PAGE_MASK; > + return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset; > +} > + > +static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) > +{ > + u64 limit, mask; > + > + if (!dev->dma_mask) > + return 0; > + > + mask = *dev->dma_mask; > + > + limit = (mask + 1) & ~mask; > + if (limit && size > limit) > + return 0; > + > + if ((addr | (addr + size - 1)) & ~mask) > + return 0; > + > + return 1; > +} > + > +static inline void dma_mark_clean(void *addr, size_t size) { } > + > /* > * DMA errors are defined by all-bits-set in the DMA address. > */ > -- > 1.7.2.5 >