Re: [PATCH v3 4/6] x86: Consolidate PCI_MMCONFIG configs

From: Andy Shevchenko <andy.shevchenko@gmail.com>
To: Bjorn Helgaas <helgaas@kernel.org>
Cc: jailhouse-dev@googlegroups.com,
	Jan Kiszka <jan.kiszka@siemens.com>,
	x86@kernel.org, linux-pci@vger.kernel.org,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	virtualization@lists.linux-foundation.org,
	Ingo Molnar <mingo@redhat.com>, "H . Peter Anvin" <hpa@zytor.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH v3 4/6] x86: Consolidate PCI_MMCONFIG configs
Date: Thu, 1 Mar 2018 18:35:50 +0200	[thread overview]
Message-ID: <CAHp75VcmGCAARtuL5xBNWRN7SLcoh_Gxfkf1shgktTKTDjHn9Q__20907.6876323254$1519922040$gmane$org@mail.gmail.com> (raw)
In-Reply-To: <20180301151359.GC13722@bhelgaas-glaptop.roam.corp.google.com>

On Thu, Mar 1, 2018 at 5:13 PM, Bjorn Helgaas <helgaas@kernel.org> wrote:
> On Thu, Mar 01, 2018 at 06:40:47AM +0100, Jan Kiszka wrote:
>> From: Jan Kiszka <jan.kiszka@siemens.com>
>>
>> Since e279b6c1d329 ("x86: start unification of arch/x86/Kconfig.*"), we
>> have two PCI_MMCONFIG entries, one from the original i386 and another
>> from x86_64. This consolidates both entries into a single one.
>>
>> The logic for x86_32, where this option was not under user control,
>> remains identical. On x86_64, PCI_MMCONFIG becomes additionally
>> configurable for SFI systems even if ACPI was disabled. This just
>> simplifies the logic without restricting the configurability in any way.
>
> Thanks for mentioning this difference.  It's probably trivial, but if
> you have any other reason to respin this series, I would split this
> into two patches:
>
>   - allow PCI_MMCONFIG on x86_64 with SFI
>   - consolidate PCI_MMCONFIG with no logical change at all
>
>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>
> But either way,
>
> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
>

If you going to respin I would suggest one more trivia

Split long depends on to two lines, like
-      depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY ||
PCI_GOOLPC || PCI_GOMMCONFIG))
+      depends on PCI
+      depends on X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC
|| PCI_GOMMCONFIG)

...

      depends on PCI && (ACPI || SFI) && (X86_64 || (PCI_GOANY ||
PCI_GOMMCONFIG))
+     depends on PCI && (ACPI || SFI)
+     depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)

(perhaps in a separate change)

>> ---
>>  arch/x86/Kconfig | 9 +++------
>>  1 file changed, 3 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
>> index eb7f43f23521..aef9d67ac186 100644
>> --- a/arch/x86/Kconfig
>> +++ b/arch/x86/Kconfig
>> @@ -2641,8 +2641,9 @@ config PCI_DIRECT
>>       depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
>>
>>  config PCI_MMCONFIG
>> -     def_bool y
>> -     depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
>> +     bool "Support mmconfig PCI config space access" if X86_64
>> +     default y
>> +     depends on PCI && (ACPI || SFI) && (X86_64 || (PCI_GOANY || PCI_GOMMCONFIG))
>>
>>  config PCI_OLPC
>>       def_bool y
>> @@ -2657,10 +2658,6 @@ config PCI_DOMAINS
>>       def_bool y
>>       depends on PCI
>>
>> -config PCI_MMCONFIG
>> -     bool "Support mmconfig PCI config space access"
>> -     depends on X86_64 && PCI && ACPI
>> -
>>  config PCI_CNB20LE_QUIRK
>>       bool "Read CNB20LE Host Bridge Windows" if EXPERT
>>       depends on PCI
>> --
>> 2.13.6
>>


-- 
With Best Regards,
Andy Shevchenko