From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH 3/3] omap: add hwspinlock device Date: Fri, 22 Oct 2010 10:28:10 -0700 Message-ID: <20101022172809.GB17595@atomide.com> References: <1287387875-14168-1-git-send-email-ohad@wizery.com> <1287387875-14168-4-git-send-email-ohad@wizery.com> <87r5fmxghm.fsf@deeprootsystems.com> <87bp6pviwf.fsf@deeprootsystems.com> <8739s0sobc.fsf@deeprootsystems.com> <20101022165612.GF9149@atomide.com> <20101022170330.GC9445@angua.secretlab.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20101022170330.GC9445@angua.secretlab.ca> Sender: linux-kernel-owner@vger.kernel.org To: Grant Likely Cc: Ohad Ben-Cohen , Kevin Hilman , Balaji T K , "Kamat, Nishant" , linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, akpm@linux-foundation.org, Greg KH , Benoit Cousson , Hari Kanigeri , Suman Anna , Simon Que List-Id: linux-omap@vger.kernel.org * Grant Likely [101022 09:54]: > On Fri, Oct 22, 2010 at 09:56:13AM -0700, Tony Lindgren wrote: > > * Ohad Ben-Cohen [101020 12:12]: > > > On Wed, Oct 20, 2010 at 8:37 PM, Kevin Hilman > > > wrote: > > > >> Let's take the i2c-omap for example. > > > >> > > > >> It sounds like it must have a predefined hwspinlock, but what if: > > > >> > > > >> 1. It will use omap_hwspinlock_request() to dynamically allocate a hwspinlock > > > >> 2. Obviously, the hwspinlock id number must be communicated to the M3 > > > >> BIOS, so the i2c-omap will publish that id using a small shared memory > > > >> entry that will be allocated for this sole purpose > > > >> 3. we will make sure that 1+2 completes before the remote processor is > > > >> taken out of reset > > > > Guys, let's try to come up with a generic interface for this instead of > > polluting the device drivers with more omap specific interfaces. > > > > We really want to keep the drivers generic and platform independent. > > > > Sure we still have some omap specific stuff in the drivers, like > > cpu_is_omapxxxx, and omap specific dma calls, but those will be going > > away. > > > > Unless somebody has better ideas, I suggest we pass a lock function > > in the platform_data to the drivers that need it, and do the omap > > specific nasty stuff in the platform code. > > For those of you going to plumbers, I'll put this on the embedded > microconference agenda when we're talking about common infrastructure. Great, thanks. Tony