Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8;
 format=flowed
Content-Transfer-Encoding: 8bit
Date:   Thu, 23 Sep 2021 13:09:45 +0300
From:   Nick Kossifidis <mick@ics.forth.gr>
To:     Philipp Tomsich <philipp.tomsich@vrull.eu>
Cc:     Nick Kossifidis <mick@ics.forth.gr>,
        Anup Patel <anup@brainfault.org>, Guo Ren <guoren@kernel.org>,
        Anup Patel <anup.patel@wdc.com>,
        Atish Patra <atish.patra@wdc.com>,
        Palmer Dabbelt <palmerdabbelt@google.com>,
        =?UTF-8?Q?Christoph_M=C3=BCllner?= <christoph.muellner@vrull.eu>,
        Christoph Hellwig <hch@lst.de>,
        liush <liush@allwinnertech.com>, wefu@redhat.com,
        =?UTF-8?Q?Wei_Wu_=28=E5=90=B4=E4=BC=9F=29?= <lazyparser@gmail.com>,
        Drew Fustini <drew@beagleboard.org>,
        linux-riscv <linux-riscv@lists.infradead.org>,
        "linux-kernel@vger.kernel.org List" <linux-kernel@vger.kernel.org>,
        taiten.peng@canonical.com, aniket.ponkshe@canonical.com,
        Heinrich Schuchardt <heinrich.schuchardt@canonical.com>,
        gordan.markus@canonical.com, Guo Ren <guoren@linux.alibaba.com>,
        Arnd Bergmann <arnd@arndb.de>, Chen-Yu Tsai <wens@csie.org>,
        Maxime Ripard <maxime@cerno.tech>,
        Daniel Lustig <dlustig@nvidia.com>,
        Greg Favor <gfavor@ventanamicro.com>,
        Andrea Mondelli <andrea.mondelli@huawei.com>,
        Jonathan Behrens <behrensj@mit.edu>,
        Xinhaoqu <xinhaoqu@huawei.com>,
        Bill Huffman <huffman@cadence.com>,
        Allen Baum <allen.baum@esperantotech.com>,
        Josh Scheid <jscheid@ventanamicro.com>,
        Richard Trauben <rtrauben@gmail.com>
Subject: Re: [PATCH] riscv: Add RISC-V svpbmt extension
Organization: FORTH
In-Reply-To: <CAAeLtUDu0yaDBcuC06nX1WUQC9k4eNuWjvAFrpkP_h0nf5BZAw@mail.gmail.com>
References: <20210923072716.913826-1-guoren@kernel.org>
 <6d7b1668c1f562a5ef426bb2519f9784@mailhost.ics.forth.gr>
 <CAAhSdy0YDP3Nk8N9fnrKgS+3Rjt=5tLCh20upmUGK9SK67nNvg@mail.gmail.com>
 <0861cc74d3886e685e9aa5d13ddcd781@mailhost.ics.forth.gr>
 <16de95480d279b086cf0c612461e4235@mailhost.ics.forth.gr>
 <CAAeLtUDu0yaDBcuC06nX1WUQC9k4eNuWjvAFrpkP_h0nf5BZAw@mail.gmail.com>
Message-ID: <88696248a0c19a5dff660354b837514d@mailhost.ics.forth.gr>
User-Agent: Roundcube Webmail/1.3.16
Precedence: bulk

Στις 2021-09-23 13:04, Philipp Tomsich έγραψε:
> 
> How if we expand this to a mmu subnode in cpu@x and add a booleans for 
> adornments like svnapot and svpbmt?
> The older mmu-type could then treated to indicate a mmu w/o any 
> adornments specified.  I am aware that this generates an additional 
> parsing-path that will be maintained, but it will allow future 
> properties to be grouped.
> 
> cpu@0 {
> ...
> mmu {
> type = "riscv,sv39";
> supports-svpbmt;
> }
> ...
> }

I was about to propose the same thing, we can do this now without 
breaking backwards compatibility, we don't really use mmu-type property 
at this point, we are either sv39 or nommu.