From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: [PATCH V2 0/3] mmc: block: Fix tuning (by avoiding it) for RPMB Date: Wed, 4 May 2016 14:38:10 +0300 Message-ID: <1462361893-11897-1-git-send-email-adrian.hunter@intel.com> Return-path: Received: from mga09.intel.com ([134.134.136.24]:44068 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752560AbcEDLmF (ORCPT ); Wed, 4 May 2016 07:42:05 -0400 Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Ulf Hansson Cc: linux-mmc , Tomas Winkler Hi The RPMB partition only allows certain commands. In particular, the tuning command (CMD21) is not allowed - refer JEDEC eMMC standard v5.1 section 6.2.2 Command restrictions. That means commands will begin failing if re-tuning is needed while switched to the RPMB partition. As we discussed here: http://marc.info/?l=linux-mmc&m=146218765801869 this patch set takes a new approach which is: Re-tune before switching to the RPMB partition Don't allow re-tuning while switched to RPMB Switch back from the RPMB partition immediately I gave it a brief test with a HS400 eMMC and using mmc utils to access RPMB. Despite all the partition switches and re-tuning in between, all RPMB operations were successful. Changes in V2: New approach entirely Adrian Hunter (3): mmc: core: Add a facility to "pause" re-tuning mmc: block: Always switch back to main area after RPMB access mmc: block: Pause re-tuning while switched to the RPMB partition drivers/mmc/card/block.c | 19 ++++++++++++++++++- drivers/mmc/core/host.c | 22 ++++++++++++++++++++++ include/linux/mmc/host.h | 4 ++++ 3 files changed, 44 insertions(+), 1 deletion(-) Regards Adrian