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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E2F0DC433FE for ; Thu, 24 Nov 2022 12:42:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229726AbiKXMmw (ORCPT ); Thu, 24 Nov 2022 07:42:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51336 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229558AbiKXMmf (ORCPT ); Thu, 24 Nov 2022 07:42:35 -0500 Received: from mail.3ffe.de (0001.3ffe.de [159.69.201.130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EB98815818 for ; Thu, 24 Nov 2022 04:42:32 -0800 (PST) Received: from 3ffe.de (0001.3ffe.de [IPv6:2a01:4f8:c0c:9d57::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail.3ffe.de (Postfix) with ESMTPSA id AECD3230D; Thu, 24 Nov 2022 13:42:30 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2022082101; t=1669293750; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RZKIn1cANNx+S4Yd+waIX76jsdNjbQtyrqMrAFlCrOw=; b=k+FOs5psBNiw8LVp3JHliZBh0Q/Id/T74+a4pqlWLf/8bdxQZWjW+VH5tLHLpKfammqHqc e0/9gu3bDuhRVFBHtFE3PXK3w95kH2u4Qen6ZLr9x4YTEy0H/ePs2NWEtZaZgUVR6Dfw+n 2Ug7k8WCrwmMkb1binZhbOHMkKuoyp1bKNcpg+/wrpSvy4LUmkrwhYsRU7B9ItHMciufnk xK12tmh2BU1VIN6XpIgznFvMljGJCWd03wKM5N1zVwJn87kW0QYyKN6y17jsgrB57z87Nh fnIJV+Bi9GpRW6iTieU0lbulrzZVel7/rpcv88v7ST4zW5BozcnBun3ZwYlMSg== MIME-Version: 1.0 Date: Thu, 24 Nov 2022 13:42:30 +0100 From: Michael Walle To: Nathan Barrett-Morrison Cc: greg.malysa@timesys.com, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, miquel.raynal@bootlin.com, pratyush@kernel.org, richard@nod.at, tudor.ambarus@microchip.com, vigneshr@ti.com Subject: Re: [PATCH 0/2] These are the required patches I found while adding In-Reply-To: <20221124114713.132514-1-nathan.morrison@timesys.com> References: <20221124114713.132514-1-nathan.morrison@timesys.com> User-Agent: Roundcube Webmail/1.4.13 Message-ID: X-Sender: michael@walle.cc Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Am 2022-11-24 12:47, schrieb Nathan Barrett-Morrison: > Ah yes, I just realized we're effectively using the device in 1S-1S-8S > extended SPI mode, so the 0xC7 setting is probably not required. We > were never able to get DTR mode working on the IS25LX256. I can fix > this patch up so it's more explicit about what's going on here. > > The 8S-8S-8S support in core.c is still going to be used for another > OSPI device I'm porting over from an older kernel. Can you link a datasheet? The problem with 8s8s8s is that it needs mode switching which can be footgun. And IMHO it doesn't provide significant performance improvements over 1s8s8s. > Would you like me to separate these patches, fix up the ISSI once, and > resubmit? Yes please. Also, I've seen that you use flags in the flash_info table. Please have a look if that information can be deduced from the SFDP. E.g. does a flash describe if it supports 1s1s8s. -michael