From: vladimir.murzin@arm.com (Vladimir Murzin)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v3 6/8] ARM: Change MPIDR_AFFINITY_LEVEL to ignore Aff3
Date: Mon, 12 Sep 2016 10:51:08 +0100 [thread overview]
Message-ID: <57D67A8C.5080103@arm.com> (raw)
In-Reply-To: <57D67A06.8090107@arm.com>
On 12/09/16 10:48, Marc Zyngier wrote:
> On 12/09/16 10:39, Vladimir Murzin wrote:
>> On 09/09/16 17:59, Marc Zyngier wrote:
>>> On 08/09/16 17:06, Vladimir Murzin wrote:
>>>> vgic-v3 driver queries CPU affinity level up to Aff3, which is valid
>>>> for arm64. However, for arm up to Aff2 levels are supported, so
>>>> querying for third level ends with upper bits of MPIDR are treated as
>>>> valid affinity level which is not true. Make sure we report zero for
>>>> any affinity level above two.
>>>>
>>>> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
>>>> ---
>>>> arch/arm/include/asm/cputype.h | 3 ++-
>>>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
>>>> index 1ee94c7..f08fac4 100644
>>>> --- a/arch/arm/include/asm/cputype.h
>>>> +++ b/arch/arm/include/asm/cputype.h
>>>> @@ -55,9 +55,10 @@
>>>>
>>>> #define MPIDR_LEVEL_BITS 8
>>>> #define MPIDR_LEVEL_MASK ((1 << MPIDR_LEVEL_BITS) - 1)
>>>> +#define MPIDR_LEVEL_SHIFT(level) (MPIDR_LEVEL_BITS * level)
>>>>
>>>> #define MPIDR_AFFINITY_LEVEL(mpidr, level) \
>>>> - ((mpidr >> (MPIDR_LEVEL_BITS * level)) & MPIDR_LEVEL_MASK)
>>>> + (((mpidr & MPIDR_HWID_BITMASK) >> MPIDR_LEVEL_SHIFT(level)) & MPIDR_LEVEL_MASK)
>>>>
>>>> #define ARM_CPU_IMP_ARM 0x41
>>>> #define ARM_CPU_IMP_INTEL 0x69
>>>>
>>>
>>> There is something I don't quite get. Is this patch really necessary?
>>> Are there cases where we construct a MPIDR that can have Aff3 set on 32bit?
>>
>> I've just checked and it seems that I've been keeping the change for
>> MPIDR_AFFINITY_LEVEL() since vgic-old era where it was used with
>>
>> static u32 compress_mpidr(unsigned long mpidr)
>> {
>> u32 ret;
>>
>> ret = MPIDR_AFFINITY_LEVEL(mpidr, 0);
>> ret |= MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8;
>> ret |= MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16;
>> ret |= MPIDR_AFFINITY_LEVEL(mpidr, 3) << 24;
>>
>> return ret;
>> }
>>
>> and now that code gone and nobody passes level 3 into this macro, so I
>> can drop this change.
>>
>> However, I do need MPIDR_LEVEL_SHIFT() macro since it is used in vgic-v3.
>>
>> Should I leave patch as is or you have something in mind?
>
> I think that for the sake of keeping the change minimal, it'd be better
> to just add the MPIDR_LEVEL_SHIFT macro, and drop the other changes.
Noted!
Thanks
Vladimir
>
> Thanks,
>
> M.
>
next prev parent reply other threads:[~2016-09-12 9:51 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-08 16:06 [PATCH v3 0/8] ARM: KVM: Support for vgic-v3 Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 1/8] arm64: KVM: Use static keys for selecting the GIC backend Vladimir Murzin
2016-09-09 9:19 ` Marc Zyngier
2016-09-09 9:33 ` Vladimir Murzin
2016-09-09 13:45 ` Vladimir Murzin
2016-09-09 14:17 ` Marc Zyngier
2016-09-09 15:14 ` Vladimir Murzin
2016-09-09 15:25 ` Marc Zyngier
2016-09-09 16:18 ` Vladimir Murzin
2016-09-09 17:06 ` Marc Zyngier
2016-09-08 16:06 ` [PATCH v3 2/8] arm64: KVM: Move GIC accessors to arch_gicv3.h Vladimir Murzin
2016-09-09 16:32 ` Marc Zyngier
2016-09-12 9:18 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 3/8] arm64: KVM: Move vgic-v3 save/restore to virt/kvm/arm/hyp Vladimir Murzin
2016-09-09 16:33 ` Marc Zyngier
2016-09-12 9:18 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 4/8] KVM: arm64: vgic-its: Introduce config option to guard ITS specific code Vladimir Murzin
2016-09-09 16:46 ` Marc Zyngier
2016-09-12 9:23 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 5/8] KVM: arm: vgic: Support 64-bit data manipulation on 32-bit host systems Vladimir Murzin
2016-09-09 16:55 ` Marc Zyngier
2016-09-12 9:25 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 6/8] ARM: Change MPIDR_AFFINITY_LEVEL to ignore Aff3 Vladimir Murzin
2016-09-09 16:59 ` Marc Zyngier
2016-09-12 9:39 ` Vladimir Murzin
2016-09-12 9:48 ` Marc Zyngier
2016-09-12 9:51 ` Vladimir Murzin [this message]
2016-09-08 16:06 ` [PATCH v3 7/8] ARM: Move system register accessors to asm/cp15.h Vladimir Murzin
2016-09-09 17:05 ` Marc Zyngier
2016-09-12 9:42 ` Vladimir Murzin
2016-09-12 9:44 ` Vladimir Murzin
2016-09-08 16:06 ` [PATCH v3 8/8] ARM: KVM: Support vgic-v3 Vladimir Murzin
2016-09-09 16:45 ` Marc Zyngier
2016-09-12 9:23 ` Vladimir Murzin
2016-09-09 7:58 ` [PATCH v3 0/8] ARM: KVM: Support for vgic-v3 Vladimir Murzin
2016-09-09 11:26 ` Christoffer Dall
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=57D67A8C.5080103@arm.com \
--to=vladimir.murzin@arm.com \
--cc=linux-arm-kernel@lists.infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).