From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from wolverine01.qualcomm.com ([199.106.114.254]:64528 "EHLO wolverine01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758637Ab0GTSPd (ORCPT ); Tue, 20 Jul 2010 14:15:33 -0400 Subject: Re: [PATCH 2/4] mm: cma: Contiguous Memory Allocator added From: Daniel Walker In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Date: Tue, 20 Jul 2010 11:15:24 -0700 Message-ID: <1279649724.26765.23.camel@c-dwalke-linux.qualcomm.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-arm-msm-owner@vger.kernel.org List-ID: To: Michal Nazarewicz Cc: linux-mm@kvack.org, Marek Szyprowski , Pawel Osciak , Xiaolin Zhang , Hiremath Vaibhav , Robert Fekete , Marcus Lorentzon , linux-kernel@vger.kernel.org, Kyungmin Park , linux-arm-msm@vger.kernel.org On Tue, 2010-07-20 at 17:51 +0200, Michal Nazarewicz wrote: > +** Use cases > + > + Lets analyse some imaginary system that uses the CMA to see how > + the framework can be used and configured. > + > + > + We have a platform with a hardware video decoder and a camera > each > + needing 20 MiB of memory in worst case. Our system is written in > + such a way though that the two devices are never used at the same > + time and memory for them may be shared. In such a system the > + following two command line arguments would be used: > + > + cma=r=20M cma_map=video,camera=r This seems inelegant to me.. It seems like these should be connected with the drivers themselves vs. doing it on the command like for everything. You could have the video driver declare it needs 20megs, and the the camera does the same but both indicate it's shared .. If you have this disconnected from the drivers it will just cause confusion, since few will know what these parameters should be for a given driver set. It needs to be embedded in the kernel. Daniel -- Sent by an consultant of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.