Date: Fri, 9 Jun 2017 17:45:53 +0100
From: Mark Rutland <mark.rutland@arm.com>
To: John Garry <john.garry@huawei.com>
Cc: Shaokun Zhang <zhangshaokun@hisilicon.com>, will.deacon@arm.com,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        anurup.m@huawei.com, tanxiaojun@huawei.com, xuwei5@hisilicon.com,
        sanil.kumar@hisilicon.com, gabriele.paoloni@huawei.com,
        shiju.jose@huawei.com, huangdaode@hisilicon.com, linuxarm@huawei.com,
        shyju.pv@huawei.com, anurupvasu@gmail.com
Subject: Re: [PATCH v8 6/9] drivers: perf: hisi: Add support for Hisilicon
 Djtag driver
Message-ID: <20170609164553.GB3043@leverpostej>
References: <1495457312-237127-1-git-send-email-zhangshaokun@hisilicon.com>
 <20170608163519.GA19643@leverpostej>
 <8666a0fa-126d-e4a3-ac4b-7962f5d79942@huawei.com>
 <20170609154425.GH10665@leverpostej>
 <e120463d-2936-90ec-8aad-f0f7be558054@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <e120463d-2936-90ec-8aad-f0f7be558054@huawei.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 515
Lines: 12

On Fri, Jun 09, 2017 at 05:09:25PM +0100, John Garry wrote:
> At this point, we would rather concentrate on our new chipset, which
> is based on same perf HW architecture (so much code reuse), but uses
> directly mapped registers and *no djtag* - in this, most of the
> upstream effort from all parties is not wasted.

FWIW, I suspect the MMIO-based PMU is going to have a smoother path
upstream, assuming it's not shared with other agents (and we don't have
another locking scheme to contend with).

Thanks,
Mark.