From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King Subject: Re: [PATCH 1/1] DSPBRIDGE: cache operation against kernel address instead of user's Date: Sat, 21 Nov 2009 19:17:25 +0000 Message-ID: <20091121191724.GA29167@flint.arm.linux.org.uk> References: <1257510861-18627-1-git-send-email-Hiroshi.DOYU@nokia.com> <20091113.121212.189727725.Hiroshi.DOYU@nokia.com> <20091117.084108.193702761.Hiroshi.DOYU@nokia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from caramon.arm.linux.org.uk ([78.32.30.218]:37012 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753373AbZKUTRc (ORCPT ); Sat, 21 Nov 2009 14:17:32 -0500 Content-Disposition: inline In-Reply-To: <20091117.084108.193702761.Hiroshi.DOYU@nokia.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Hiroshi DOYU Cc: linux-omap@vger.kernel.org, omar.ramirez@ti.com, ameya.palande@nokia.com, h-kanigeri2@ti.com, x0095840@ti.com, nm@ti.com, Miguel.Verdu@nokia.com, bshah@ti.com, imre.deak@nokia.com On Tue, Nov 17, 2009 at 08:41:08AM +0200, Hiroshi DOYU wrote: > From: Hiroshi DOYU > Subject: Re: [PATCH 1/1] DSPBRIDGE: cache operation against kernel address instead of user's > Date: Fri, 13 Nov 2009 12:12:12 +0200 (EET) > > > From: "Doyu Hiroshi (Nokia-D/Helsinki)" > > Subject: [PATCH 1/1] DSPBRIDGE: cache operation against kernel address instead of user's > > Date: Fri, 6 Nov 2009 13:34:21 +0100 > > > > > From: Hiroshi DOYU > > > > > > Based on the discussion: > > > http://www.spinics.net/lists/arm-kernel/msg72810.html > > > > > > HACK: export "follow_page()" for dspbridge cache operation > > > > > > Signed-off-by: Hiroshi DOYU > > > --- > > Now there's no need for homebrewed cache function because we use > kernel address and can pass "virt_addr_valid()" check in > "dma_cache_maint()". Note that with the advent of ARMv7/Cortex A9, dma_cache_maint() is going away - and probably will be gone during the next merge window. There is no directly equivalent replacement for it - it is being replaced by two sets of functions, one to be called prior to DMA and another to be called after DMA has completed. In the longer run, it is likely that the 'dmac_*_range' and 'outer_*_range' will probably also be going away, to be replaced by two new per-cpu methods along the lines of the above. I think this may throw a spanner in the works for this patch, but it's necessary to make Cortex A9 work. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: