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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 E805DC433DF for ; Mon, 8 Jun 2020 20:41:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C55BA2076C for ; Mon, 8 Jun 2020 20:41:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sang-engineering.com header.i=@sang-engineering.com header.b="l4NudZ+M" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726714AbgFHUlR (ORCPT ); Mon, 8 Jun 2020 16:41:17 -0400 Received: from www.zeus03.de ([194.117.254.33]:37016 "EHLO mail.zeus03.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726566AbgFHUlQ (ORCPT ); Mon, 8 Jun 2020 16:41:16 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=sang-engineering.com; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=k1; bh=lfRlR6rk2IoTNg54fbivRcobce3D Ce6/iyfI/FoAao8=; b=l4NudZ+Md4P0yig/iC5VtKIDZs0cgxh9TOZadm4uY8Qt Gi7BjWgzLam6A6VoE6BXyQ/62il0sCaW564AvYn3d20/I3KZ8mtcBqe4oGPonw/0 Znqjsq6YSF8N1tutRR8ThaHGhpQ7L6/CbF4T+WBeWZf9sF2IsnXmYTWyHl5e/e4= Received: (qmail 3137612 invoked from network); 8 Jun 2020 22:41:14 +0200 Received: by mail.zeus03.de with ESMTPSA (TLS_AES_256_GCM_SHA384 encrypted, authenticated); 8 Jun 2020 22:41:14 +0200 X-UD-Smtp-Session: l3s3148p1@aIrEoZinIoQgAwDPXwXUAIYwoJSUoKNc Date: Mon, 8 Jun 2020 22:41:14 +0200 From: Wolfram Sang To: Yoshihiro Shimoda Cc: "linux-mmc@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" Subject: Re: [PATCH 1/2] mmc: core: when downgrading HS400, callback into drivers earlier Message-ID: <20200608204113.GC917@ninjato> References: <20200604112040.22144-1-wsa+renesas@sang-engineering.com> <20200604112040.22144-2-wsa+renesas@sang-engineering.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="GPJrCs/72TxItFYR" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org --GPJrCs/72TxItFYR Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Shimoda-san, thank you very much for the review! > > The driver specific downgrade function makes more sense if we run it > > before we switch anything, not after we already switched. Otherwise some > > non-HS400 communication has already happened. > >=20 > > No need to convert users. There is only one currenty which needs this > > change in a later patchset. >=20 > Perhaps, should we add Fixes tag like below? >=20 > Fixes: ba6c7ac3a2f4 ("mmc: core: more fine-grained hooks for HS400 tuning= ") I am not sure. While it is more correct to move the call to hs400_downgrade upwards, it does not really fix a bug on its own. Without patch 2/2 of this series, there is not really a huge difference when we disable the SCC the old way. For the new way, this patch is a prerequisite. > > + /* Prepare host to downgrade to HS timing */ > > + if (host->ops->hs400_downgrade) > > + host->ops->hs400_downgrade(host); > > + >=20 > IICU, we should call hs400_downgrade() between the __mmc_switch("EXT_CSD_= TIMING_HS") > and mmc_set_timing(card->host, MMC_TIMING_MMC_HS) because the switch comm= and should > be issued in HS400 mode. Yes, of course, you are right. Will fix! Kind regards, Wolfram --GPJrCs/72TxItFYR Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAl7eomkACgkQFA3kzBSg Kbb0dw/+IU1CyXHkDLpFjZWmvXBJoVZRsi6HF8MvNbabaGPWw36gkISpfZ4aZHgo VHk0zWGSnTDOYM6cBTYfz8m8cO2+4ULp2vbxdW5jThklxstICFeBXV73DhHE5yoS 1mskaAnSiuvCFu5QNLWGZkAk0FbSmkl1k3iNRifqH7BuafTR0AqqTGOqgJ5fGH/8 FjrBVUtZHYM+VIcdRonMf/BXzx3DX8tAr8pxF7DKurIHZT/LCWmQ7w88ZykWjSV+ 5gw5LZC6N9HzyC9P6OvXGurtnzovQEXkPxUANwPavddjghVkNIGkXMf8RoVl4lgl 06te1UgzewW/U0qIsU8OqxLvffGL65WK+oyzYcKzvp75AS0oMk2UmBgT/w9JwfTK T146VxkD5KxKpbwH6eruITNAvIPCE5rH4dRbkcof5ecD8uEFcg+u/wZp/eB6/URR 19HcddbiBD3mdwTU3TNTZLfJvfZF0vtv7Wcc+0xx/rVRPGjmU1Gby8nNyWtUjWir HFXLbZtYU7/u6PQlW1FdTQvfKdJLTyO4YGyq7T+d0ocCFNWNIedV84/lHQUar5b8 iclRvm3IhkLqerUgjtnFE9YrU45OTmiygTnaq10XdquFAmmQ9uDb2nPsAqbtTPtx ps0qE20X9sqytR09J1coq+n0j4aLz3WZRrlpISDgCJqvuGQNqlY= =hZd4 -----END PGP SIGNATURE----- --GPJrCs/72TxItFYR--