From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1F796C433F5 for ; Mon, 16 May 2022 18:06:23 +0000 (UTC) Received: from localhost ([::1]:37462 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nqf6r-0007sl-Tx for qemu-devel@archiver.kernel.org; Mon, 16 May 2022 14:06:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48658) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nqf5J-0006jQ-7a; Mon, 16 May 2022 14:04:45 -0400 Received: from [187.72.171.209] (port=33208 helo=outlook.eldorado.org.br) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nqf5H-0001qS-74; Mon, 16 May 2022 14:04:44 -0400 Received: from p9ibm ([10.10.71.235]) by outlook.eldorado.org.br over TLS secured channel with Microsoft SMTPSVC(8.5.9600.16384); Mon, 16 May 2022 15:04:36 -0300 Received: from [127.0.0.1] (unknown [10.10.70.45]) by p9ibm (Postfix) with ESMTPS id B13F5800048; Mon, 16 May 2022 15:04:36 -0300 (-03) Message-ID: Date: Mon, 16 May 2022 15:04:36 -0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: Re: [PATCH v2 2/5] target/riscv: Disable "G" by default Content-Language: en-US To: Tsukasa OI , Alistair Francis , Frank Chang Cc: qemu-devel@nongnu.org, qemu-riscv@nongnu.org References: From: =?UTF-8?Q?V=c3=adctor_Colombo?= In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-OriginalArrivalTime: 16 May 2022 18:04:37.0045 (UTC) FILETIME=[67B18650:01D8694F] X-Host-Lookup-Failed: Reverse DNS lookup failed for 187.72.171.209 (failed) Received-SPF: pass client-ip=187.72.171.209; envelope-from=victor.colombo@eldorado.org.br; helo=outlook.eldorado.org.br X-Spam_score_int: -4 X-Spam_score: -0.5 X-Spam_bar: / X-Spam_report: (-0.5 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.001, PDS_HP_HELO_NORDNS=0.659, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 14/05/2022 23:56, Tsukasa OI wrote: > Because "G" virtual extension expands to "IMAFD", we cannot separately > disable extensions like "F" or "D" without disabling "G". Because all > "IMAFD" are enabled by default, it's harmless to disable "G" by default. > > Signed-off-by: Tsukasa OI > --- > target/riscv/cpu.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c > index 00bf26ec8b..3ea68d5cd7 100644 > --- a/target/riscv/cpu.c > +++ b/target/riscv/cpu.c > @@ -812,7 +812,7 @@ static Property riscv_cpu_properties[] = { > /* Defaults for standard extensions */ > DEFINE_PROP_BOOL("i", RISCVCPU, cfg.ext_i, true), > DEFINE_PROP_BOOL("e", RISCVCPU, cfg.ext_e, false), > - DEFINE_PROP_BOOL("g", RISCVCPU, cfg.ext_g, true), > + DEFINE_PROP_BOOL("g", RISCVCPU, cfg.ext_g, false), > DEFINE_PROP_BOOL("m", RISCVCPU, cfg.ext_m, true), > DEFINE_PROP_BOOL("a", RISCVCPU, cfg.ext_a, true), > DEFINE_PROP_BOOL("f", RISCVCPU, cfg.ext_f, true), > -- > 2.34.1 > > I think the logic looks ok, and (with my limited understanding of the code) I agree on the reasoning for the changes in patches 2 and 3. Just some clarification needed: where is the value of 'g' checked? can the behavior change in this patch cause a situation where IMAFD_Zicsr_Zifencei is set but 'g' is not, or does patch 3 guarantee that in this case 'g' will be set? Thanks! -- Víctor Cora Colombo Instituto de Pesquisas ELDORADO Aviso Legal - Disclaimer