From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754464AbbIOOtF (ORCPT ); Tue, 15 Sep 2015 10:49:05 -0400 Received: from relay1.mentorg.com ([192.94.38.131]:36375 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754212AbbIOOsp (ORCPT ); Tue, 15 Sep 2015 10:48:45 -0400 Subject: Re: [PATCH] misc: sram: extend usage of reserved partitions To: Greg Kroah-Hartman References: <1439156402-10207-1-git-send-email-vladimir_zapolskiy@mentor.com> <1439156402-10207-2-git-send-email-vladimir_zapolskiy@mentor.com> <20150810032728.GA29840@kroah.com> <55C88128.9000204@mentor.com> CC: Philipp Zabel , =?UTF-8?Q?Heiko_St=c3=bcbner?= , Arnd Bergmann , From: Vladimir Zapolskiy Message-ID: <55F82F76.6020405@mentor.com> Date: Tue, 15 Sep 2015 17:47:18 +0300 User-Agent: Mozilla/5.0 (X11; Linux i686; rv:38.0) Gecko/20100101 Icedove/38.1.0 MIME-Version: 1.0 In-Reply-To: <55C88128.9000204@mentor.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [137.202.0.76] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Greg, On 10.08.2015 13:47, Vladimir Zapolskiy wrote: > Hi Greg, > > On 10.08.2015 06:27, Greg Kroah-Hartman wrote: >> On Mon, Aug 10, 2015 at 12:40:02AM +0300, Vladimir Zapolskiy wrote: >>> This change adds functionality to operate on reserved SRAM partitions >>> described in device tree file. Two partition properties are added, >>> "pool" and "export", the first one allows to share a specific partition >>> for usage by a kernel consumer in the same manner as it is done for >>> the whole SRAM device, and "export" property provides access to some >>> SRAM area from userspace over sysfs interface. Practically it is >>> possible to specify both properties for an SRAM partition, however >>> simultaneous access from a kernel consumer and from userspace is not >>> serialized, but still the combination may be useful for debugging >>> purpose. >>> >>> Signed-off-by: Vladimir Zapolskiy >>> --- >>> To test SRAM partition export to userspace it might be sufficient >>> to add an exported subnode, write data to created binary attribute file, >>> do soft reboot and read the contents of the same binary attribute >>> file. Aware of any potential use of SRAM by a bootloader etc. >>> >>> To give an idea how to use "pool" partition feature here is an example >>> for Freescale iMX6Q SabreAuto with CODA driver as a user: >>> >>> arch/arm/boot/dts/imx6q.dtsi @@ -82,6 +82,10 @@ >>> compatible = "mmio-sram"; >>> reg = <0x00900000 0x40000>; >>> clocks = <&clks IMX6QDL_CLK_OCRAM>; >>> + >>> + #address-cells = <1>; >>> + #size-cells = <1>; >>> + ranges = <0 0x00900000 0x40000>; >>> }; >>> >>> aips-bus@02000000 { /* AIPS1 */ >>> arch/arm/boot/dts/imx6qdl-sabreauto.dtsi @@ -490,3 +490,18 @@ >>> 0x0000c000 0x1404a38e 0x00000000>; >>> }; >>> }; >>> + >>> +&ocram { >>> + #address-cells = <1>; >>> + #size-cells = <1>; >>> + >>> + vpu_iram: vpu_iram { >>> + reg = <0x00008000 0x00021000>; >>> + pool; >>> + }; >>> +}; >>> + >>> +&vpu { >>> + iram = <&vpu_iram>; >>> +}; >>> >> >> Putting a diff in a patch changelog is tricky, do you really need it? > > you are right, it is tricky, that's why this is actually not a valid > diff, I tested on my environment and the email can be applied with git-am. on the second glance this quasi-diff is located outside of the commit message, it is in the section under --- line and before the actual change. git-am digests it. >> And why send 2 copies of this patch, what changed? >> >> confused, >> > > sorry for confusion, occasionally I gave two same files to > git-send-email. The versions are absolutely identical, please ignore one > of them. Please let me know, if you like to see any updates to the change. The updated genalloc interfaces used by the change are found in v4.3.0-rc1. -- With best wishes, Vladimir