From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from elvis.franken.de (elvis.franken.de [193.175.24.41]) by smtp.subspace.kernel.org (Postfix) with ESMTP id B4D921E485; Wed, 2 Jul 2025 13:19:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.175.24.41 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751462347; cv=none; b=AX+tqf4FU4eu/JTHzk7QXzpld7wXIOqxObRDfORmwesF0gwIAuTW7opHcLi1/Yj4FPP8HZBDiIBdjXwBrR6WYjr8EnGkNwzmhRbdNUcSHVb6+Yn3n7J2rHsCB7BtvszebkTZd1BQFIkrmCwd5Z1RV+P4B1LUk2KbEFKLTu9BHhQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751462347; c=relaxed/simple; bh=a3Wyp5SqjigUho7y7SxxcO6AUOzylt0NJ22sAZJxEPE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ZDnihphMIOmyBNZT6hXnfHuG3GA7F0KksF85al6P+XDkWTqXblHuijimC1BIs55mwhwBoMCWQQ0QM+3aut8okhHwKVFw3dvtvq3vfoIp1Z0+pRxNcKn2odRekYmt7IeOY8NZ4n0qG2HhXNOVLsVWL+gV3BP+jAn1YGS+7yHH+Yw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=alpha.franken.de; spf=pass smtp.mailfrom=alpha.franken.de; arc=none smtp.client-ip=193.175.24.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=alpha.franken.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=alpha.franken.de Received: from uucp by elvis.franken.de with local-rmail (Exim 3.36 #1) id 1uWwab-00058O-00; Wed, 02 Jul 2025 14:29:25 +0200 Received: by alpha.franken.de (Postfix, from userid 1000) id B451FC0C37; Wed, 2 Jul 2025 14:08:48 +0200 (CEST) Date: Wed, 2 Jul 2025 14:08:48 +0200 From: Thomas Bogendoerfer To: Jiaxun Yang Cc: Gregory CLEMENT , Vladimir Kondratiev , =?iso-8859-1?Q?Th=E9o?= Lebrun , Tawfik Bayouk , Thomas Petazzoni , "linux-mips@vger.kernel.org" , linux-kernel@vger.kernel.org Subject: Re: [PATCH] MIPS: disable MMID if GINVT is not usable Message-ID: References: <20250625-mmid_disable_no_ginv_on_noc-v1-1-38a3902607a7@bootlin.com> <808e21d2-1212-4358-9ba6-29f9d097be8a@app.fastmail.com> Precedence: bulk X-Mailing-List: linux-mips@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <808e21d2-1212-4358-9ba6-29f9d097be8a@app.fastmail.com> On Wed, Jun 25, 2025 at 03:44:00PM +0100, Jiaxun Yang wrote: > 在2025年6月25日周三 下午2:27，Gregory CLEMENT写道： > > Hi Gregory, > > > If System-level Interconnect (aka Network on Chip) does not support > > the global invalidation, then MMID feature is not usable. Indeed the > > current implementation of MMID relies on the GINV* instruction. > > Yes, it is the case if the NoC IP can't handle AMBA ACE DVM requests. > > > > > Signed-off-by: Gregory CLEMENT > > --- > > arch/mips/Kconfig | 6 ++++++ > > arch/mips/include/asm/cpu-features.h | 5 ++++- > > arch/mips/mobileye/Kconfig | 2 ++ > > 3 files changed, 12 insertions(+), 1 deletion(-) > > > > diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig > > index > > 1e48184ecf1ec8e29c0a25de6452ece5da835e30..05ce008459b89f03fa71d94429607feb9d06526f > > 100644 > > --- a/arch/mips/Kconfig > > +++ b/arch/mips/Kconfig > > @@ -2575,6 +2575,12 @@ config WAR_R10000_LLSC > > config WAR_MIPS34K_MISSED_ITLB > > bool > > > > +# Some I6500 based SoC do not support the global invalidation on their > > +# System-level Interconnect (aka Network on Chip), this have an > > +# influence on the MMID support. > > +config GINVT_UNSUPPORTED_NOC > > + bool > > + > > I believe this should be a DeviceTree property of CM node instead of Kconfig > hack. Either that or by a runtime check, if possible. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]