Subject: [PATCH 10/11] XEN / PCI: Remove the dependence on arch x86 when PCI_MMCONFIG=y

From: [email-masked] (Tomasz Nowicki)
Date: Tue, 26 May 2015 16:54:51 +0200

On 26.05.2015 16:00, Boris Ostrovsky wrote:
> On 05/26/2015 09:54 AM, Boris Ostrovsky wrote:
>> On 05/26/2015 08:49 AM, Hanjun Guo wrote:
>>> In drivers/xen/pci.c, there are arch x86 dependent codes when
>>> CONFIG_PCI_MMCONFIG is enabled, since CONFIG_PCI_MMCONFIG
>>> depends on ACPI, so this will prevent XEN PCI running on other
>>> architectures using ACPI with PCI_MMCONFIG enabled (such as ARM64).
>>>
>>> Fortunatly, it can be sloved in a simple way. In drivers/xen/pci.c,
>>> the only x86 dependent code is if ((pci_probe & PCI_PROBE_MMCONF) == 0),
>>> and it's defined in asm/pci_x86.h, the code means that
>>> if the PCI resource is not probed in PCI_PROBE_MMCONF way, just
>>> ingnore the xen mcfg init. Actually this is duplicate, because
>>> if PCI resource is not probed in PCI_PROBE_MMCONF way, the
>>> pci_mmconfig_list will be empty, and the if (list_empty())
>>> after it will do the same job.
>>>
>>> So just remove the arch related code and the head file, this
>>> will be no functional change for x86, and also makes xen/pci.c
>>> usable for other architectures.
>>>
>>> Signed-off-by: Hanjun Guo <[email-masked]>
>>> CC: Konrad Rzeszutek Wilk <[email-masked]>
>>> CC: Boris Ostrovsky <[email-masked]>
>>> ---
>>>   drivers/xen/pci.c | 6 ------
>>>   1 file changed, 6 deletions(-)
>>>
>>> diff --git a/drivers/xen/pci.c b/drivers/xen/pci.c
>>> index 6785ebb..9a8dbe3 100644
>>> --- a/drivers/xen/pci.c
>>> +++ b/drivers/xen/pci.c
>>> @@ -28,9 +28,6 @@
>>>   #include <asm/xen/hypervisor.h>
>>>   #include <asm/xen/hypercall.h>
>>>   #include "../pci/pci.h"
>>> -#ifdef CONFIG_PCI_MMCONFIG
>>> -#include <asm/pci_x86.h>
>>> -#endif
>>>
>>>   static bool __read_mostly pci_seg_supported = true;
>>>
>>> @@ -222,9 +219,6 @@ static int __init xen_mcfg_late(void)
>>>       if (!xen_initial_domain())
>>>           return 0;
>>>
>>> -    if ((pci_probe & PCI_PROBE_MMCONF) == 0)
>>> -        return 0;
>>> -
>>>       if (list_empty(&pci_mmcfg_list))
>>>           return 0;
>>>
>>
>> (+Stefano who is Xen ARM maintainer)
>>
>> This will not build on x86 since pci_mmcfg_list since, for example,
>> pci_mmcfg_list is declared in pci_x86.h.
>
>
> And now really with Stefano and with parsable first sentence, sorry:
>
>
> This will not build on x86 since pci_mmcfg_list, for example, is
> declared in pci_x86.h.

With this patch set, not any more. Please see preceding patches.

Regards,
Tomasz