From mboxrd@z Thu Jan  1 00:00:00 1970
From: Julien Grall <julien.grall@citrix.com>
Subject: Re: [PATCH v6 10/31] xen/arm: ITS: Introduce gic_is_lpi
 helper function
Date: Thu, 3 Sep 2015 10:48:14 +0100
Message-ID: <55E8175E.9080406@citrix.com>
References: <1441019208-2764-1-git-send-email-vijay.kilari@gmail.com>
	<1441019208-2764-11-git-send-email-vijay.kilari@gmail.com>
	<55E48592.8080905@citrix.com>
	<CALicx6sxMqsf9E_9_MM1K=rAMiZnvXjbAUXv90R7N8CkBSP0VA@mail.gmail.com>
	<55E58E9C.3040404@citrix.com>
	<CALicx6t8MnBZyJ8aSAGRP+DQF2g5r2=iF9Ptb7CJDVYfugNdgQ@mail.gmail.com>
	<55E5A1E1.9040208@citrix.com>
	<CALicx6tx06M+0d0cgsfnwRw7OGSyWq9MaGUaBD=DBx+UdMvpiw@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"; Format="flowed"
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xen.org>
In-Reply-To: <CALicx6tx06M+0d0cgsfnwRw7OGSyWq9MaGUaBD=DBx+UdMvpiw@mail.gmail.com>
List-Unsubscribe: <http://lists.xen.org/cgi-bin/mailman/options/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xen.org>
List-Help: <mailto:xen-devel-request@lists.xen.org?subject=help>
List-Subscribe: <http://lists.xen.org/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=subscribe>
Sender: xen-devel-bounces@lists.xen.org
Errors-To: xen-devel-bounces@lists.xen.org
To: Vijay Kilari <vijay.kilari@gmail.com>
Cc: Zoltan Kiss <zoltan.kiss@huawei.com>, Ian Campbell <Ian.Campbell@citrix.com>, Stefano Stabellini <stefano.stabellini@eu.citrix.com>, Prasun Kapoor <Prasun.Kapoor@caviumnetworks.com>, Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>, Tim Deegan <tim@xen.org>, "xen-devel@lists.xen.org" <xen-devel@lists.xen.org>, Stefano Stabellini <stefano.stabellini@citrix.com>, manish.jaggi@caviumnetworks.com
List-Id: xen-devel@lists.xenproject.org

Hi,

On 03/09/2015 07:32, Vijay Kilari wrote:
> On Tue, Sep 1, 2015 at 6:32 PM, Julien Grall <julien.grall@citrix.com> wrote:
>> On 01/09/15 12:56, Vijay Kilari wrote:
>>>> BTW, I suggested to create a field nr_lpis but you decided to store the
>>>> number of bits supported. Why?
>>>
>>> I have nr_lpis field in vgic structure (patch #17). But it just tells
>>> how LPIs are supported
>>> for a domain.
>>
>> Why are you speaking about vgic structure? I'm only suggesting to
>> replace you nr_id_bits by nr_lpis in the hw GIC. AFAICT, there is
>> nothing to prevent having 2 field using the same name on 2 differents
>> structure...
>>
>>> Where as nr_id_bits shows total number of  lpis that hw supports.
>>
>> No nr_id_bits shows the total number of interrupt not LPIs. The total
>> number of LPIs is (1 << nr_id_bits) - 8092. Although (1 << nr_id_bits)
>> gives you the last LPI interrupt ID supported.
>>
>> Anyway, as I said earlier, re-calculating the last LPI interrupt ID
>> everytime based on the shift is time consuming. You should optimize for
>> the common case rather than using copy the raw value (i.e ID bits) from
>> the HW directly.
>>
>> Maybe the name "max_lpi_id" would make more sense to you for a name?
>
> Instead of storing max_lpi_id which is ( 1 << nr_id_bits) - 8192, I prefer
> to rename nr_id_bits as nr_irq_ids which can be initialized to (1 << nr_id_bits)
> for gicv3 and gicv2_info.nr_lines for gicv2.

I'm fine with that.

Regards,

-- 
Julien Grall