Message-ID: <4FA2C746.5080000@wwwdotorg.org>
Date: Thu, 03 May 2012 11:58:30 -0600
From: Stephen Warren <swarren@wwwdotorg.org>
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To: Hiroshi DOYU <hdoyu@nvidia.com>
CC: linux-tegra@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        Joerg Roedel <joerg.roedel@amd.com>,
        Thierry Reding <thierry.reding@avionic-design.de>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCHv3 3/4] iommu/tegra: smmu: Refrain from accessing to AHB
References: <1336061147-10245-1-git-send-email-hdoyu@nvidia.com> <1336061147-10245-3-git-send-email-hdoyu@nvidia.com> <4FA2C4E9.2080509@wwwdotorg.org>
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On 05/03/2012 11:48 AM, Stephen Warren wrote:
> On 05/03/2012 10:05 AM, Hiroshi DOYU wrote:
>> Use "tegra_ahb_enable_smmu()" to inform AHB that SMMU is
>> ready, instead of directly aceessing AHB registers.

Oh, that should be "accessing".

>> @@ -911,14 +899,16 @@ static int tegra_smmu_probe(struct platform_device *pdev)
> 
>> +	smmu->ahb = of_parse_phandle(pdev->dev.of_node, "ahb", 0);
> 
> Hmm, "ahb" should probably be "nvidia,ahb".
> 
> I see that neither this patch nor the next patch include binding
> documentation that describe this property. Can you please add documentation.

Oh, the next patch is just adding the entry to the .dtsi file for the
AHB, so no surprise it doesn't add a binding document for the SMMU!

I see that with this patch, the driver still expects the DMA window to
be represented as a reg property (IORESOURCE_MEM), so if we add a
binding document to this patch it won't be very consistent either:-( And
then, there's the issue of whether the SMMU should be it's own device or
a child of some MC device, since there's non-SMMU functionality in these
registers too. This makes all the SMMU rework need a little more thought.

So, I propose dropping this patch from this series, since this series is
all about adding the AHB driver. We should move this patch to a series
relating to the SMMU driver.
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