Re: [Qemu-arm] [Qemu-devel] [PATCH v4 09/14] pci: Add support for Designware IP block

[Andrey Smirnov]

On Wed, Jan 17, 2018 at 7:23 AM, Marcel Apfelbaum
<address@hidden> wrote:
>
> Hi Peter,
>
>
> On 16/01/2018 16:34, Peter Maydell wrote:
>>
>> On 16 January 2018 at 01:37, Andrey Smirnov <address@hidden>
>> wrote:
>>>
>>> Add code needed to get a functional PCI subsytem when using in
>>> conjunction with upstream Linux guest (4.13+). Tested to work against
>>> "e1000e" (network adapter, using MSI interrupts) as well as
>>> "usb-ehci" (USB controller, using legacy PCI interrupts).
>>>
>>> Cc: Peter Maydell <address@hidden>
>>> Cc: Jason Wang <address@hidden>
>>> Cc: Philippe Mathieu-Daudé <address@hidden>
>>> Cc: address@hidden
>>> Cc: address@hidden
>>> Cc: address@hidden
>>> Signed-off-by: Andrey Smirnov <address@hidden>
>>> ---
>>>   default-configs/arm-softmmu.mak  |   2 +
>>>   hw/pci-host/Makefile.objs        |   2 +
>>>   hw/pci-host/designware.c         | 618
>>> +++++++++++++++++++++++++++++++++++++++
>>>   include/hw/pci-host/designware.h |  93 ++++++
>>>   include/hw/pci/pci_ids.h         |   2 +
>>>   5 files changed, 717 insertions(+)
>>>   create mode 100644 hw/pci-host/designware.c
>>>   create mode 100644 include/hw/pci-host/designware.h
>>
>> I'm not familiar enough with our PCI code to be able to review
>> this, I'm afraid. MST and Marcel are our PCI subsystem maintainers --
>> could one of you have a look at whether this seems to be a correct
>> implementation of a pcie host controller ?
>
>
> Sadly PCI Host bridges do not have a standard, each HW vendor
> can do pretty much what they want.
>
> That being said, if Andrey can point me to the PCI spec for the Designware
> PCI host bridge and what parts they implemented for it I can have a look,
> sure.
> (I will not be available for a week or so, but right after)
>

Just in case you still want this:

To the best of my knowledge, Synposys does not provide specification
for their PCIe IP to general public and I am in no way affiliated with
them, so I don't have any backchannels to get it any other way.

The next best thing to an actual spec, that I found to be pretty
useful, is PCIe chapter of i.MX6Q Reference Manual
(https://www.nxp.com/docs/en/reference-manual/IMX6DQRM.pdf   page
4049), which is what I used to implement the code in question.

Last, and probably the most important, "source of truth" was actual
Linux PCIe driver for i.MX/Designware which I used as a sort of
inverse reference implementation.

Thanks,
Andrey Smirnov