[PATCH V2 00/23] MMCONFIG refactoring and support for ARM64 PCI hostbridge init based on ACPI

Tomasz Nowicki tn at semihalf.com
Fri Dec 18 04:26:20 PST 2015


On 17.12.2015 22:24, Sinan Kaya wrote:
> Hi Tomasz,
>
> On 12/16/2015 10:16 AM, Tomasz Nowicki wrote:
>>  From the functionality point of view this series might be split into the
>> following logic parts:
>> 1. Make MMCONFIG code arch-agnostic which allows all architectures to collect
>>     PCI config regions and used when necessary.
>> 2. Move non-arch specific bits to the core code.
>> 3. Use MMCONFIG code and implement generic ACPI based PCI host
>>     controller driver.
>> 4. Enable above driver on ARM64
>>
>> Patches has been built on top of 4.4-rc4 and can be found here:
>> git at github.com:semihalf-nowicki-tomasz/linux.git (pci-acpi-v2)
>>
>> NOTE, this patch set depends on Matthew's patches:
>> http://www.spinics.net/lists/linux-pci/msg45950.html
>> https://github.com/Vality/linux/tree/pci-fixes
>>
>> This has been tested on Cavium ThunderX 1 socket server and QEMU.
>> Any help in reviewing and testing is very appreciated.
>>
>> v1 -> v2
>> - moved non-arch specific piece of code to dirver/acpi/ directory
>> - fixed IO resource handling
>> - introduced PCI config accessors quirks matching
>> - moved ACPI_COMPANION_SET to generic code
>>
>
> Just tested your series. I'm seeing a resource assignment problem below.
> The bus addresses show as memory addresses and memory addresses show as
> bus addresses and IO resource did not show up.
>
>
> Tomasz V2
>
> [    2.520852] ACPI: PCI Interrupt Link [LN1C] (IRQs *238)
> [    2.535472] ACPI: PCI Interrupt Link [LN1D] (IRQs *239)
> [    2.550562] ACPI: PCI Root Bridge [PCI2] (domain 0002 [bus 00-1f])
> [    2.567813] acpi PNP0A08:02: _OSC: OS supports [ExtendedConfig ASPM ClockPM Segments MSI]
> [    2.591270] acpi PNP0A08:02: _OSC: platform does not support [PCIeHotplug]
> [    2.611144] acpi PNP0A08:02: _OSC: OS now controls [PME AER PCIeCapability]
> [    2.630299] ACPI: IORT: can't find node related to (null) device
> [    2.647184]_acpi_PNP0A08:02:_PCI_host_bridge_to_bus_0002:00
> [    2.662663] pci_bus 0002:00: root bus resource [mem 0x00100000-0x3fffffff window] (bus address [0xfffff5ff00100000-0xfffff5ff3fffffff])
> [    2.703561] pci_bus 0002:00: root bus resource [mem 0x40000000-0x7fffffff window] (bus address [0xfffff5fe80000000-0xfffff5febfffffff])
> [    2.737737] pci_bus 0002:00: root bus resource [mem 0x80000000-0xffffffff window] (bus address [0xfffff5fe00000000-0xfffff5fe7fffffff])
> [    2.794961] pci_bus 0002:00: root bus resource [bus 00-1f]
>
> Mark Salter's patches
>
> [    2.730011] ACPI: PCI Interrupt Link [LN1C] (IRQs *238)
> [    2.744648] ACPI: PCI Interrupt Link [LN1D] (IRQs *239)
> [    2.759330] ACPI: PCI Root Bridge [PCI2] (domain 0002 [bus 00-1f])
> [    2.783295] acpi PNP0A08:02: _OSC: OS supports [ExtendedConfig ASPM ClockPM Segments MSI]
> [    2.806726] acpi PNP0A08:02: _OSC: platform does not support [PCIeHotplug]
> [    2.826005] acpi PNP0A08:02: _OSC: OS now controls [PME AER PCIeCapability]
> [    2.845361] PCI host bridge to bus 0002:00
> [    2.856719]_pci_bus_0002:00:_root_bus_resource_[bus_00-1f]
> [    2.872056] pci_bus 0002:00: root bus resource [mem 0xa0100100000-0xa013fffffff] (bus address [0x00100000-0x3fffffff])
> [    2.902008] pci_bus 0002:00: root bus resource [mem 0xa0200000000-0xa023fffffff] (bus address [0x40000000-0x7fffffff])
> [    2.932396] pci_bus 0002:00: root bus resource [mem 0xa0300000000-0xa037fffffff] (bus address [0x80000000-0xffffffff])
> [    2.983827] pci_bus 0002:00: root bus resource [io  0x0000-0xffff]
>
> Here is how the ACPI table looks like:
>
> 		QWORDMemory(			// Consumed-And-prodced resource(all of memory space)
> 			ResourceProducer,	// bit 0 of general flags is 0
> 			PosDecode,		// positive Decode:  		_DEC
> 			MinFixed,		// Range is fixed:   		_MIF
> 			MaxFixed,		// Range is fixed:   		_MAF
> 			NonCacheable,		// 				_MEM
> 			ReadWrite,		// 				_RW
> 			0x00000000,		// Granularity: 	   	_GRA
> 			0x00100000,		// Min - PCI Memory start: 	_MIN
> 			0x3FFFFFFF,		// Max - PCI Memory end:   	_MAX
> 			0xA0100000000,		// Translation: 		_TRA
> 			0x3FF00000,		// Range Length: 		_LEN
> 			,			// Optional field left blank
> 			,			// Optional field left blank
> 			MEM0,			// Name declaration for this descriptor
> 			AddressRangeMemory,
> 			TypeStatic
> 			)
>
>
> Any thoughts?
>
>

Yes, this is because of:
[PATCH V2 20/23] ACPI, PCI: Refine the way to handle translation_offset 
for ACPI resources
which should have RFC tag. I posted this patch to re-trigger discussion 
on this.

The patch does not add Translation offset to the MMIO type resource 
start address and for acpi_pci_probe_root_resources(ci) causes problems 
like that. Indeed MMIO has to be fixed.

But IO resource type is more problematic. Actually, how 
acpi_decode_space() should parse resources and which ACPI IO descriptor 
should be used for ARM64: QWORDIO (offset == 0 vs offset != 0), DWordIO 
(TypeStatic vs TypeTranslation) + backward compatibility with IA64...

Please refer to:
https://lkml.org/lkml/2015/11/5/581

As Lorenzo pointed out, we *all* need to agree upon the IO resource ACPI 
descriptor and its parsing method.

Any comments are very appreciated!

Tomasz



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