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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 D705CC433EF for ; Wed, 16 Feb 2022 19:57:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ZJ4k8D8uCacIpIYmwtTNDpHiX8wJk8HiIP5bXpeb5Os=; b=g+HNu5i/GqM2BG f3eqdinNDwt74gdIK/blNzBRD2FTsSHqyQ1I220Q9uDjpgi95/rI6UuTbxATTlhDWLex/IClcvkxD ZT24R1T4Bzqdk42pfEzS1aJRNZzz7GX98iHdFPTYaf9R5biG5Svw+3MnEhkcwVonnrQzUyeyx7tfC Fk9ss4zBnvkrELPh0hyEtQYcbtdXoOa2GtUcR4hir46XBM/55fswGJpUZ8DKdvltyEnmp/w/U3XiM eNdj5Ijw/TZFrI57UKNBkLxrKT79iUFMabyQoPIUmEnAumjYAkUVFwpJ3Zaap37E3218a3w0QthTX ZEw1aM4DzyxeXPsjsolQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nKQQU-008Gpj-He; Wed, 16 Feb 2022 19:57:22 +0000 Received: from elvis.franken.de ([193.175.24.41]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nKQQR-008GnR-MP; Wed, 16 Feb 2022 19:57:21 +0000 Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1nKQQI-00055x-01; Wed, 16 Feb 2022 20:57:10 +0100 Received: by alpha.franken.de (Postfix, from userid 1000) id 84055C250A; Wed, 16 Feb 2022 20:54:23 +0100 (CET) Date: Wed, 16 Feb 2022 20:54:23 +0100 From: Thomas Bogendoerfer To: Chuanhong Guo Cc: linux-mips@vger.kernel.org, Rui Salvaterra , Ilya Lipnitskiy , linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] MIPS: ralink: mt7621: do memory detection on KSEG1 Message-ID: <20220216195423.GA17551@alpha.franken.de> References: <20220211001345.3429572-1-gch981213@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220211001345.3429572-1-gch981213@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220216_115719_911603_9B04C440 X-CRM114-Status: GOOD ( 16.19 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Fri, Feb 11, 2022 at 08:13:44AM +0800, Chuanhong Guo wrote: > It's reported that current memory detection code occasionally detects > larger memory under some bootloaders. > Current memory detection code tests whether address space wraps around > on KSEG0, which is unreliable because it's cached. > > Rewrite memory size detection to perform the same test on KSEG1 instead. > While at it, this patch also does the following two things: > 1. use a fixed pattern instead of a random function pointer as the magic > value. > 2. add an additional memory write and a second comparison as part of the > test to prevent possible smaller memory detection result due to > leftover values in memory. > > Fixes: 139c949f7f0a MIPS: ("ralink: mt7621: add memory detection support") > Reported-by: Rui Salvaterra > Signed-off-by: Chuanhong Guo > --- > arch/mips/ralink/mt7621.c | 36 +++++++++++++++++++++++------------- > 1 file changed, 23 insertions(+), 13 deletions(-) applied to mips-fixes. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ] _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek