From mboxrd@z Thu Jan  1 00:00:00 1970
From: sathyanarayanan kuppuswamy
        <sathyanarayanan.kuppuswamy@linux.intel.com>
Subject: Re: [PATCH v1 1/2] PCI: ATS: Add function to check ATS page aligned
 request status.
Date: Thu, 7 Feb 2019 14:16:13 -0800
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To: Sinan Kaya <okaya@kernel.org>, bhelgaas@google.com, joro@8bytes.org, dwmw2@infradead.org
Cc: linux-pci@vger.kernel.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Ashok Raj <ashok.raj@intel.com>, Jacob Pan <jacob.jun.pan@linux.intel.com>, Keith Busch <keith.busch@intel.com>
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On 2/7/19 12:38 PM, Sinan Kaya wrote:
>
> On 2/7/2019 1:41 PM, sathyanarayanan.kuppuswamy@linux.intel.com wrote:
>> + * As per PCI spec, If page aligned request bit is set, it indicates
>> + * the untranslated address is always aligned to a 4096 byte boundary.
>> + */
>> +int pci_ats_page_aligned(struct pci_dev *pdev)
>> +{
>> +    u16 cap;
>> +
>> +    if (!pdev->ats_cap)
>> +        return 0;
>> +
>> +    pci_read_config_word(pdev, pdev->ats_cap + PCI_ATS_CAP, &cap);
>
> If I remember this right, aligned request is only supported on ATS v1.1
> but not supported on v1.0.
Its added in v1.1.
>
> Can you please check the spec?
>
-- 
Sathyanarayanan Kuppuswamy
Linux kernel developer