From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: Problems with dma_alloc_coherent() From: Adrian Cox To: Paul Mackerras Cc: John Whitney , Linux/PPC Development In-Reply-To: <16493.61242.908659.82167@cargo.ozlabs.ibm.com> References: <9EB527A2-83F5-11D8-9FF0-000A95A07384@sands-edge.com> <20040401100546.A27472@home.com> <4317F0F4-8405-11D8-9FF0-000A95A07384@sands-edge.com> <20040401181926.GA3630@gate.ebshome.net> <406C658E.10500@embeddededge.com> <20040401185956.GB3786@gate.ebshome.net> <2C2F00BD-8410-11D8-9FF0-000A95A07384@sands-edge.com> <20040401191715.GC3786@gate.ebshome.net> <406C8104.9050609@acm.org> <20040401220018.GA4130@gate.ebshome.net> <16493.61242.908659.82167@cargo.ozlabs.ibm.com> Content-Type: text/plain Message-Id: <1080977598.7999.791.camel@newt> Mime-Version: 1.0 Date: Sat, 03 Apr 2004 08:33:19 +0100 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Fri, 2004-04-02 at 23:54, Paul Mackerras wrote: > If you want to write code to handle a separate DMA controller, go > ahead. You will need to design your own separate API for it. I > wouldn't try to make it too general, though, since there are very few > systems these days that have DMA controllers (as distinct from > bus-master capable I/O devices). Actually, they are extremely common in the embedded market. On my desk I have three Linux systems with this class of DMA engine: an MPC107/7410, an ARM9 from Cirrus, and an ARM9 from TI. Most system-on-a-chip processors have DMA engines which can move between any two of memory, PCI, and internal peripherals. - Adrian Cox ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/