Date: Fri, 22 Sep 2017 10:37:03 +0100
From: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
To: Hanjun Guo <guohanjun@huawei.com>
Cc: Mayuresh Chitale <mchitale@apm.com>, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org,
        jens.wiklander@linaro.org, patches@apm.com
Subject: Re: [PATCH] tee: ACPI support for optee driver
Message-ID: <20170922093703.GD1523@red-moon>
References: <1505977937-25034-1-git-send-email-mchitale@apm.com>
 <59C36E18.1050106@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <59C36E18.1050106@huawei.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 897
Lines: 23

On Thu, Sep 21, 2017 at 03:45:28PM +0800, Hanjun Guo wrote:
> On 2017/9/21 15:12, Mayuresh Chitale wrote:
> > This patch modifies the optee driver to add support for parsing
> > the conduit method from an ACPI node.
> 
> Sorry I didn't involve this earlier, but I think this is a wrong
> approach, in ACPI 5.1+ spec, there is a bit in FADT table which
> indicates PSCI using SMC or HVC, please see ACPI 6.2 [1],
> Table 5-37 Fixed ACPI Description Table ARM Boot Architecture Flags.
> 
> Can we just use that to get the conduit method for optee driver too?
> 
> [1]: http://www.uefi.org/sites/default/files/resources/ACPI_6_2.pdf

It is just not a matter of conduit method but also to define how OPTEE
should be detected. It is up to Linaro (who owns OP-TEE) to put forward
a binding at ACPI (ARM) spec level.

We do not define ACPI bindings on a kernel mailing list.

NAK on this patch.

Lorenzo