From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932336AbcFGJWg (ORCPT ); Tue, 7 Jun 2016 05:22:36 -0400 Received: from mail-yw0-f173.google.com ([209.85.161.173]:33794 "EHLO mail-yw0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932158AbcFGJWc (ORCPT ); Tue, 7 Jun 2016 05:22:32 -0400 MIME-Version: 1.0 In-Reply-To: <575690CB.5080501@arm.com> References: <575690CB.5080501@arm.com> From: Baolin Wang Date: Tue, 7 Jun 2016 17:22:25 +0800 Message-ID: Subject: Re: [PATCH] arm64: Implement arch_setup_pdev_archdata hook To: Robin Murphy Cc: catalin.marinas@arm.com, will.deacon@arm.com, jroedel@suse.de, Andrew Morton , Jisheng Zhang , Suravee.Suthikulpanit@amd.com, Arnd Bergmann , linux-arm-kernel@lists.infradead.org, LKML , Mark Brown , Felipe Balbi Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7 June 2016 at 17:15, Robin Murphy wrote: > On 07/06/16 09:29, Baolin Wang wrote: >> >> Now on ARM64 platform, it will set 'dummy_dma_ops' for device dma_ops if >> it did not call 'arch_setup_dma_ops' at device creation time by issuing >> platform_device_alloc() function, that will cause failure when setting >> the dma mask for device. > > > Yes, that's rather the whole point. DMA-capable devices are real hardware, > therefore don't spring out of thin air without being described in DT or > ACPI. OK. > > Please elaborate on the situation that you're attempting to address here > (please don't let it be the ongoing Designware USB catastrophe ;)) Yes, like you mentioned, we met problems at DesignWare USB3 controller host glue, do you have any better solutions to solve this problem? Thanks. > > Robin. > > >> Hence We need to hook the archdata to setup proper dma_ops for these >> devices. >> >> Signed-off-by: Baolin Wang >> --- >> arch/arm64/mm/dma-mapping.c | 21 +++++++++++++++++++++ >> 1 file changed, 21 insertions(+) >> >> diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c >> index c566ec8..04e057b 100644 >> --- a/arch/arm64/mm/dma-mapping.c >> +++ b/arch/arm64/mm/dma-mapping.c >> @@ -26,6 +26,7 @@ >> #include >> #include >> #include >> +#include >> >> #include >> >> @@ -961,3 +962,23 @@ void arch_setup_dma_ops(struct device *dev, u64 >> dma_base, u64 size, >> dev->archdata.dma_coherent = coherent; >> __iommu_setup_dma_ops(dev, dma_base, size, iommu); >> } >> + >> +void arch_setup_pdev_archdata(struct platform_device *pdev) >> +{ >> + if (!pdev->dev.archdata.dma_ops) >> + pdev->dev.archdata.dma_ops = &swiotlb_dma_ops; >> + >> + /* >> + * Set default coherent_dma_mask to 32 bit. Drivers are expected >> to >> + * setup the correct supported mask. >> + */ >> + if (!pdev->dev.coherent_dma_mask) >> + pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32); >> + >> + /* >> + * Set it to coherent_dma_mask by default if the architecture >> + * code has not set it. >> + */ >> + if (!pdev->dev.dma_mask) >> + pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask; >> +} >> > -- Baolin.wang Best Regards