From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: [PATCH v4 0/3] mmc: sdhci: Set DMA mask properly Date: Wed, 16 Mar 2016 14:46:24 +0200 Message-ID: <56E955A0.7010502@intel.com> References: <1457316477-8153-1-git-send-email-acourbot@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: Received: from mga09.intel.com ([134.134.136.24]:43309 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932069AbcCPMuC (ORCPT ); Wed, 16 Mar 2016 08:50:02 -0400 In-Reply-To: <1457316477-8153-1-git-send-email-acourbot@nvidia.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Alexandre Courbot , Ulf Hansson , Arnd Bergmann Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, gnurou@gmail.com On 07/03/16 04:07, Alexandre Courbot wrote: > 64-bit capable devices are supposed to set their own DMA mask. Currently > this does not happen for sdhci devices excepted for the two (sdhci-acpi > and sdhci-pci) that define a enable_dma() hook and do it there. However > this hook is called from several places while DMA mask is supposed to > be set only once ; for instance the sdhci-acpi driver maintains a flag > just to make sure the DMA mask is set only upon the first call of this > hook. > > For the vast majority of drivers that do not define a enable_dma() hook, the > default 32-bit DMA mask is used and there is a risk of using unneeded bounce > buffers on hosts capable of 64-bit addressing. > > The first patch adds a default DMA mask setting function that is called when > a DMA-capable host is added. It tries to set sane DMA masks according to the > device's reported capabilities. > > The addition of this function seems to make the same code in sdhci-acpi and > sdhci-pci redundant, so it is removed from these drivers. On top of making > this series a negative line count, it also removes one usage of the obsolete > pci_set_dma_mask() function. > > Changes since v3: > - Unset the SDHCI_USE_64_BIT_DMA flag if setting of 64-bit mask failed > - Carry Acked-bys > > Alexandre Courbot (3): > mmc: sdhci: Set DMA mask when adding host > mmc: sdhci-acpi: Remove enable_dma() hook > mmc: sdhci-pci: Do not set DMA mask in enable_dma() > > drivers/mmc/host/sdhci-acpi.c | 30 ------------------------ > drivers/mmc/host/sdhci-pci-core.c | 15 ------------ > drivers/mmc/host/sdhci.c | 48 +++++++++++++++++++++++++++++++++------ > 3 files changed, 41 insertions(+), 52 deletions(-) > I had a couple of questions which have been answered, so for all 3 patches: Acked-by: Adrian Hunter