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 X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 071B4C433B4 for ; Fri, 9 Apr 2021 09:29:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B51E66101E for ; Fri, 9 Apr 2021 09:29:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233056AbhDIJ3R (ORCPT ); Fri, 9 Apr 2021 05:29:17 -0400 Received: from mx2.suse.de ([195.135.220.15]:48686 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232795AbhDIJ3E (ORCPT ); Fri, 9 Apr 2021 05:29:04 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id D2F35AFF4; Fri, 9 Apr 2021 09:28:50 +0000 (UTC) Message-ID: Subject: Re: [PATCH 4/4] ARM: dts: Fix-up EMMC2 controller's frequency From: Nicolas Saenz Julienne To: Alan Cooper Cc: Stefan Wahren , Nicolas Saenz Julienne , "moderated list:BROADCOM BCM7XXX ARM ARCHITECTURE" , linux-mmc , DTML , BCM Kernel Feedback , linux-rpi-kernel@lists.infradead.org, Florian Fainelli , phil@raspberrypi.com, Tim Gover , Scott Branden , Adrian Hunter , ": Linux Kernel Mailing List" , Ulf Hansson , Rob Herring Date: Fri, 09 Apr 2021 11:28:48 +0200 In-Reply-To: References: <20210322185816.27582-1-nsaenz@kernel.org> <20210322185816.27582-5-nsaenz@kernel.org> <401100ea-90ad-57b1-50da-967118a090da@i2se.com> <78dec30c052e9bb76e52c38f3da5af371e5d65f5.camel@suse.de> <2d2a2638-8213-5d6e-0a3a-927ed5bb2ed7@i2se.com> <4d4e3de99dbee711cf47878bf98a7cc34c3f1e65.camel@suse.de> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-Ym8B8RdTuXiurQ06o0vs" User-Agent: Evolution 3.40.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-Ym8B8RdTuXiurQ06o0vs Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Al, On Wed, 2021-04-07 at 16:37 -0400, Alan Cooper wrote: > Nicolas, >=20 > I got a better description of the failure and it looks like the bus > clock needs to be limited to 300KHz for a 500MHz core clock. > What's happening is that an internal reset sequence is needed after a > command timeout and the reset signal needs to be asserted for at least > 2 ticks of the bus clock. This is done using a 12 bit counter clocked > by the core clock. That means a 500MHz core clock produces a 122KHz > reset signal which is too fast for 2 ticks of the 200KHz bus clock > (100KHz) but is okay for the 300KHz (150Khz) bus clock. Thanks for the info. I'll work something out. Regards, Nicolas --=-Ym8B8RdTuXiurQ06o0vs Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEErOkkGDHCg2EbPcGjlfZmHno8x/4FAmBwHlAACgkQlfZmHno8 x/4gRQgAqmBf1qUXbQh2Hj7zqrgMN3ckta7yGgR0oNhkpCmRGRatEwSCgxH13qs8 EaRs7buxvfuE9DnBBbJJk6PYaX5WMzeLQSInVFFFVInlpP2ElyAvRWICqV11bjHr ZjUOPsZW+vQfgGDBB4FedDI5htLwgDp63/mPfgJwM/qDd6kbgFENXnidO3y3PSEK 64PHea0sjHLNSitCQlWjfi/XAst+vIl6O2mTbzzdQtGgt2+2fCaST5cbGPsi7Re9 mY1J3T2IfibcBQg/yV8h7pIPPkqMfK4IQFOSG1Tpunvviz7ABCfccuNgbLcNg6LC a8mHlp+jb+4LKg5ENQxkBMCSOWMIRw== =H6Ip -----END PGP SIGNATURE----- --=-Ym8B8RdTuXiurQ06o0vs-- 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 X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0EA88C433ED for ; Fri, 9 Apr 2021 09:31:49 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 75D64611BE for ; Fri, 9 Apr 2021 09:31:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 75D64611BE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: MIME-Version:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID: Reply-To:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date :Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=VCb70vKRYguJ+G8WxiU0XNzkLNDjzygPNpA17yp5hPc=; b=rceELtCKL2nOfk7wo+o17Hvbo DKaht77VZjJerJlNOz3VR996REkTk39p6l3N4r7wWX9GY2vI/nhOT7yfEeSMe8vHcFLJk0DJKF1nk /vBdiJc9GNU6Ne/RY7uLEwFSsTQ4ZZoJ7GQsKUvR0sDdNEwxYYiDSZmPis2JOrKEV//81HTh23NyK GVbfvwHiuRouTftZYPYIISMr2D47BlEY7N/KeV6r7oZrNeua1LOhxAZ7zaF1IyZrN9eUMM0icqqVL AYK0vdTc7zhMxlNkc098MtE1MwZ4NUe8uxGYZlRLGcShH7OE/q+P0QtXWryPcb9jmQpabG1gHyjQd CBsQWF95Q==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lUnSg-000Esb-K6; Fri, 09 Apr 2021 09:29:59 +0000 Received: from mx2.suse.de ([195.135.220.15]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lUnRb-000Ede-EL; Fri, 09 Apr 2021 09:28:53 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id D2F35AFF4; Fri, 9 Apr 2021 09:28:50 +0000 (UTC) Message-ID: Subject: Re: [PATCH 4/4] ARM: dts: Fix-up EMMC2 controller's frequency From: Nicolas Saenz Julienne To: Alan Cooper Cc: Stefan Wahren , Nicolas Saenz Julienne , "moderated list:BROADCOM BCM7XXX ARM ARCHITECTURE" , linux-mmc , DTML , BCM Kernel Feedback , linux-rpi-kernel@lists.infradead.org, Florian Fainelli , phil@raspberrypi.com, Tim Gover , Scott Branden , Adrian Hunter , ": Linux Kernel Mailing List" , Ulf Hansson , Rob Herring Date: Fri, 09 Apr 2021 11:28:48 +0200 In-Reply-To: References: <20210322185816.27582-1-nsaenz@kernel.org> <20210322185816.27582-5-nsaenz@kernel.org> <401100ea-90ad-57b1-50da-967118a090da@i2se.com> <78dec30c052e9bb76e52c38f3da5af371e5d65f5.camel@suse.de> <2d2a2638-8213-5d6e-0a3a-927ed5bb2ed7@i2se.com> <4d4e3de99dbee711cf47878bf98a7cc34c3f1e65.camel@suse.de> User-Agent: Evolution 3.40.0 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210409_102851_754114_D7915AA0 X-CRM114-Status: GOOD ( 13.60 ) X-BeenThere: linux-arm-kernel@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: multipart/mixed; boundary="===============5830490299912790390==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============5830490299912790390== Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-Ym8B8RdTuXiurQ06o0vs" --=-Ym8B8RdTuXiurQ06o0vs Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Al, On Wed, 2021-04-07 at 16:37 -0400, Alan Cooper wrote: > Nicolas, >=20 > I got a better description of the failure and it looks like the bus > clock needs to be limited to 300KHz for a 500MHz core clock. > What's happening is that an internal reset sequence is needed after a > command timeout and the reset signal needs to be asserted for at least > 2 ticks of the bus clock. This is done using a 12 bit counter clocked > by the core clock. That means a 500MHz core clock produces a 122KHz > reset signal which is too fast for 2 ticks of the 200KHz bus clock > (100KHz) but is okay for the 300KHz (150Khz) bus clock. Thanks for the info. I'll work something out. Regards, Nicolas --=-Ym8B8RdTuXiurQ06o0vs Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEErOkkGDHCg2EbPcGjlfZmHno8x/4FAmBwHlAACgkQlfZmHno8 x/4gRQgAqmBf1qUXbQh2Hj7zqrgMN3ckta7yGgR0oNhkpCmRGRatEwSCgxH13qs8 EaRs7buxvfuE9DnBBbJJk6PYaX5WMzeLQSInVFFFVInlpP2ElyAvRWICqV11bjHr ZjUOPsZW+vQfgGDBB4FedDI5htLwgDp63/mPfgJwM/qDd6kbgFENXnidO3y3PSEK 64PHea0sjHLNSitCQlWjfi/XAst+vIl6O2mTbzzdQtGgt2+2fCaST5cbGPsi7Re9 mY1J3T2IfibcBQg/yV8h7pIPPkqMfK4IQFOSG1Tpunvviz7ABCfccuNgbLcNg6LC a8mHlp+jb+4LKg5ENQxkBMCSOWMIRw== =H6Ip -----END PGP SIGNATURE----- --=-Ym8B8RdTuXiurQ06o0vs-- --===============5830490299912790390== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --===============5830490299912790390==--