From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933661AbcAMUkc (ORCPT ); Wed, 13 Jan 2016 15:40:32 -0500 Received: from mout.kundenserver.de ([217.72.192.75]:54478 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932213AbcAMUka (ORCPT ); Wed, 13 Jan 2016 15:40:30 -0500 From: Arnd Bergmann To: Brijesh Singh Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, mark.rutland@arm.com, devicetree@vger.kernel.org, pawel.moll@arm.com, ijc+devicetree@hellion.org.uk, linux-ide@vger.kernel.org, robh+dt@kernel.org, galak@codeaurora.org, tj@kernel.org Subject: Re: [PATCH] ata: add AMD Seattle platform driver Date: Wed, 13 Jan 2016 21:39:48 +0100 Message-ID: <10776629.UCmL1lPAav@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: <56968168.4010606@amd.com> References: <1452200002-31590-1-git-send-email-brijesh.singh@amd.com> <4689728.Nn3Rl2cUeP@wuerfel> <56968168.4010606@amd.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:GFB7opcB+qqcFPbcZVgg7KmyjVGx6sfyijd9k5O6qPE+HL0zDJX NpEqMsSU51KkNzoMstRxuFd29UqC1/ZMA+jUr2OZ8koKDqwSgHrm6FdGBeyzSTk08vRZRc2 xBoNB7N6dfsg7xlLrDQdOSG1XqBQ4NyG+Dk547uIdtOPavl1GkCGPcD3eaZwWb+3M2sku07 ue/tj7/daLMAKAorWwzRw== X-UI-Out-Filterresults: notjunk:1;V01:K0:6kqfLJdCHPw=:6eMdpzuZaXkAzWSzK5yWl/ llWpc3I3muPKf/2NS4BoumlCC1iMKMBfBeITcG4smO0angAWw2j6vqpSNOWKVQt+JfS36Uvj4 g5j5/OJtNalqrT+4+AqY5yyTZbM8ynvP8c2EDy5Sz4MbtuhyfPzXkjhdegyvINCIZTDkk8s1a 0Yna2Cb/vx5jrLODR+nqdD2Y0CoLZJQitWK/o0Acg/3aN7+KwKwacq7kbcO0yQTN2sGtW05ix KCzv2tsVm5GoZa+DYSIa/gvJDfJX0SK2yRpHC0K/S5CUmFcxogtXVTqTPNA2KQdGC4OLc4xoZ BercZI8NvGI+/A3DxaQGR7tyg4FgxlvEk46Ur8AYPnvrb9FES4a2zcKAR8j0N4lqEJgJCmkBO EpkxhigPxlyunAXXAUo9DWUw3IrhZAH+CfjiFGvg51GsL/jgYOrgUgAek4F+3vj03c36y4Tpp VS39ippgQ0gxZmp8+kq1SaZVGv330ShUt2mXdoJsn90Xyiq8evuxHbrG3cD1mcdjYqlvu/xVE TOgigiN7iWn5NO4X49ej9jIRfP/Oda09E5muujjef5mkxlWpCMQHGuLBi8w/SHOckLPDbo1Q8 4uTXbdOUISnYeGjGxplFRUw+0thAbbMQLzJmaOeSoKrix7A3LD//EnvuDh3KtRrkSFLQait31 3gNwE2l6j6ywXTVbPK+qyc2PeeuDAkSw8oU8xKd6pu3B6ps1hzNzU0YB9OC4+79R+Ipj5kSiw y+qIK2Si9K296mlb Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 13 January 2016 10:55:04 Brijesh Singh wrote: > On 01/12/2016 08:24 AM, Arnd Bergmann wrote: > > c) calling into the ACPI interpreter to do platform specific hacks > > Thanks for explaining. Now I understood your comment on AML however we need to consider the following: > > a) activity LED blinking routines are called very frequent (10 to 100ms based on emp->state) and executing AML method that often would introduces its own overhead. > > b) all BIOS vendors need to implement a new methods in their DSDT and release a new BIOS. > > c) other OS'es (mainly Windows) driver need to be updated. > > > We don't know how many other SoC's have similar hacky implementation which can take advantage of extending generic > AHCI driver to call into AML methods for LED blink. Given some of these causes I think having a platform driver is much cleaner. I can drop DT binding part from this driver and keep just ACPI binding. > > Thoughts ? I don't care what you do with ACPI, just make sure we can use the generic driver without any platform specific hacks for the DT case. For ACPI, please talk to the respective maintainers about whether they want to have a custom driver for this case, or a proper abstraction in the generic driver. Arnd