From patchwork Wed Apr 8 09:46:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wolfram Sang X-Patchwork-Id: 11479707 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2752C92A for ; Wed, 8 Apr 2020 09:46:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 082BA2074F for ; Wed, 8 Apr 2020 09:46:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727917AbgDHJqw (ORCPT ); Wed, 8 Apr 2020 05:46:52 -0400 Received: from sauhun.de ([88.99.104.3]:39634 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726345AbgDHJqw (ORCPT ); Wed, 8 Apr 2020 05:46:52 -0400 Received: from localhost (p54B334FE.dip0.t-ipconnect.de [84.179.52.254]) by pokefinder.org (Postfix) with ESMTPSA id E6CED2C1F39; Wed, 8 Apr 2020 11:46:49 +0200 (CEST) From: Wolfram Sang To: linux-mmc@vger.kernel.org Cc: linux-renesas-soc@vger.kernel.org, Yoshihiro Shimoda , Wolfram Sang Subject: [PATCH v2 0/3] mmc: renesas_sdhi: improve TAP selection if all TAPs are good Date: Wed, 8 Apr 2020 11:46:35 +0200 Message-Id: <20200408094638.10375-1-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org SDHI (with SCC) has a mechanism to select an optimal TAP even if all were considered good during the tuning process. This series implements support for it. Before that, some refactoring of 'best TAP selection' is done to avoid code duplication and get more understandable code. This work is based on BSP patches by Masaharu Hayakawa and Takeshi Saito. It is built on top of mmc/next. For convenience, a branch is here: git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git renesas/sdhi/new_manual_calib It has been tested on Renesas Salvator-XS boards (R-Car M3-N and R-Car H3 ES2.0). There were no regressions detected. HS400 could be tuned the same way, and checksumming large files still works. And while this series is useful by itself, it is also the last prerequisite to implement some 'bad tap avoidance' on top which is what we are originally aiming for. Note about backporting: The super useful iterator bitmap_for_each_set_region() is only available since v5.6. If you want that before, you need to backport the needed bits of e837dfde15a4 ("bitmap: genericize percpu bitmap region iterators"), too. Thank you to Shimoda-san for his valuable input since the RFT version of this patchset (see patch 1 for details)! Kind regards, Wolfram Wolfram Sang (3): mmc: renesas_sdhi: refactor calculation of best TAP mmc: renesas_sdhi: clarify handling of selecting TAPs mmc: renesas_sdhi: improve TAP selection if all TAPs are good drivers/mmc/host/renesas_sdhi.h | 2 + drivers/mmc/host/renesas_sdhi_core.c | 64 ++++++++++++++-------------- 2 files changed, 34 insertions(+), 32 deletions(-)