Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT) initial support.

From	Marc Zyngier <marc.zyngier@arm.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT) initial support.
Date	2016-04-14 09:40 +0200
Message-ID	<rnK2C-6Al-29@gated-at.bofh.it> (permalink)
References	(2 earlier) <rnuTT-3hb-5@gated-at.bofh.it> <rnv3A-3mt-7@gated-at.bofh.it> <rnvmW-3u7-17@gated-at.bofh.it> <rnAmC-7DR-11@gated-at.bofh.it> <rnJSW-6wh-3@gated-at.bofh.it>
Organization	ARM Ltd

Show all headers | View raw

On 14/04/16 08:20, Tomasz Nowicki wrote:
> On 13.04.2016 23:18, Sinan Kaya wrote:
>> On 4/13/2016 11:52 AM, Marc Zyngier wrote:
>>>>> Sure. Please see:
>>>>> http://infocenter.arm.com/help/topic/com.arm.doc.den0049a/DEN0049A_IO_Remapping_Table.pdf
>>>>> 3.1.1.5 PCI root complex node
>>>>> PCI Segment number -> The PCI segment number, as in MCFG and as
>>>>> returned by _SEG in the namespace.
>>>>>
>>>>> So IORT spec states that pci_segment_number corresponds to the segment
>>>>> number from MCFG table and _SEG method. Here is my patch which makes
>>>>> sure pci_domain_nr(bus) is set properly:
>>>>> https://lkml.org/lkml/2016/2/16/418
>>> Lovely. So this series is actually dependent on the PCI one. I guess we
>>> need to solve that one first, because IORT seems pretty pointless if we
>>> don't have PCI support. What's the plan?
>>
>> Would it be OK to split the PCI specific section of the patch and continue
>> review? PCI is a user of the IORT table. Not the other way around.
> 
> I need to disagree. What would be the use case for patches w/o "PCI part" ?

Quite. PCI (as a subsystem) doesn't need IORT at all, thank you very
much. GIC (implementing MSI) and SMMU (implementing DMA) do, by virtue
of RID/SID/DID being translated all over the place.

So by the look of it, the dependency chain is GIC+SMMU->IORT->PCI.

The GIC changes here are pretty mechanical, and not that interesting.
The stuff that needs sorting quickly is PCI, because all this work is
pointless if we don't have it.

At the risk of sounding like a stuck record: What's the plan?

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...

Thread

[PATCH V4 0/7] Introduce ACPI world to ITS irqchip Tomasz Nowicki <tn@semihalf.com> - 2016-04-04 11:00 +0200
  [PATCH V4 7/7] acpi, gicv3, its: Use MADT ITS subtable to do PCI/MSI domain initialization. Tomasz Nowicki <tn@semihalf.com> - 2016-04-04 11:00 +0200
  [PATCH V4 2/7] irqchip, GICv3, ITS: Cleanup for ITS domain initialization. Tomasz Nowicki <tn@semihalf.com> - 2016-04-04 11:00 +0200
    Re: [PATCH V4 2/7] irqchip, GICv3, ITS: Cleanup for ITS domain  initialization. Marc Zyngier <marc.zyngier@arm.com> - 2016-04-13 16:20 +0200
  [PATCH V4 5/7] irqchip, gicv3, its: Probe ITS in the ACPI way. Tomasz Nowicki <tn@semihalf.com> - 2016-04-04 11:00 +0200
    Re: [PATCH V4 5/7] irqchip, gicv3, its: Probe ITS in the ACPI way. Marc Zyngier <marc.zyngier@arm.com> - 2016-04-14 11:10 +0200
  [PATCH V4 3/7] irqchip, GICv3, ITS: Refator ITS DT init code to prepare for ACPI. Tomasz Nowicki <tn@semihalf.com> - 2016-04-04 11:00 +0200
    Re: [PATCH V4 3/7] irqchip, GICv3, ITS: Refator ITS DT init code to  prepare for ACPI. Tomasz Nowicki <tn@semihalf.com> - 2016-04-12 12:20 +0200
    Re: [PATCH V4 3/7] irqchip, GICv3, ITS: Refator ITS DT init code to  prepare for ACPI. Marc Zyngier <marc.zyngier@arm.com> - 2016-04-13 17:10 +0200
  [PATCH V4 6/7] its, pci, msi: Factor out code that might be reused for ACPI. Tomasz Nowicki <tn@semihalf.com> - 2016-04-04 11:00 +0200
  [PATCH V4 1/7] acpi, pci: Setup MSI domain on a per-devices basis. Tomasz Nowicki <tn@semihalf.com> - 2016-04-04 11:00 +0200
    Re: [PATCH V4 1/7] acpi, pci: Setup MSI domain on a per-devices  basis. Marc Zyngier <marc.zyngier@arm.com> - 2016-04-13 12:20 +0200
      Re: [PATCH V4 1/7] acpi, pci: Setup MSI domain on a per-devices  basis. Tomasz Nowicki <tn@semihalf.com> - 2016-04-13 12:50 +0200
  [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT) initial support. Tomasz Nowicki <tn@semihalf.com> - 2016-04-04 11:00 +0200
    Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT)  initial support. Marc Zyngier <marc.zyngier@arm.com> - 2016-04-13 17:30 +0200
      Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT)  initial support. Tomasz Nowicki <tn@semihalf.com> - 2016-04-13 17:40 +0200
        Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT)  initial support. Marc Zyngier <marc.zyngier@arm.com> - 2016-04-13 18:00 +0200
          Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT)  initial support. Sinan Kaya <okaya@codeaurora.org> - 2016-04-13 23:20 +0200
            Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT)  initial support. Tomasz Nowicki <tn@semihalf.com> - 2016-04-14 09:30 +0200
              Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT)  initial support. Marc Zyngier <marc.zyngier@arm.com> - 2016-04-14 09:40 +0200
                Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT)  initial support. okaya@codeaurora.org - 2016-04-14 13:40 +0200
                Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT)  initial support. Marc Zyngier <marc.zyngier@arm.com> - 2016-04-14 13:50 +0200
          Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT)  initial support. Tomasz Nowicki <tn@semihalf.com> - 2016-04-14 09:40 +0200
            Re: [PATCH V4 4/7] ARM64, ACPI, PCI: I/O Remapping Table (IORT)  initial support. Marc Zyngier <marc.zyngier@arm.com> - 2016-04-14 09:50 +0200
  Re: [PATCH V4 0/7] Introduce ACPI world to ITS irqchip Tomasz Nowicki <tn@semihalf.com> - 2016-04-12 09:40 +0200

csiph-web