| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <2811939.DFy94j5OEx@avalon> Date: Mon, 26 Aug 2013 15:18 +0200 From: Laurent Pinchart <laurent.pinchart@...asonboard.com> To: Richard Zhao <linuxzsc@...il.com>, "linux-omap@...r.kernel.org" <linux-omap@...r.kernel.org> Cc: Stephen Warren <swarren@...dotorg.org>, "vinod.koul@...el.com" <vinod.koul@...el.com>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, Richard Zhao <rizhao@...dia.com>, "linux-arm-kernel@...ts.infradead.org" <linux-arm-kernel@...ts.infradead.org> Subject: Re: [PATCH] DMA: let filter functions of of_dma_simple_xlate possible check of_node Hi Richard, (Dropping Dan Williams from the CC list as his e-mail address doesn't seem to be valid anymore) On Monday 26 August 2013 20:55:57 Richard Zhao wrote: > On Mon, Aug 26, 2013 at 02:17:43PM +0200, Laurent Pinchart wrote: > > On Friday 23 August 2013 09:57:43 Stephen Warren wrote: > > > On 08/22/2013 07:29 PM, Richard Zhao wrote: > > > > On Fri, Aug 23, 2013 at 04:18:27AM +0800, Stephen Warren wrote: > > > >> On 08/21/2013 11:19 PM, Richard Zhao wrote: > > > >>> On Fri, Aug 02, 2013 at 10:00:00AM +0800, Richard Zhao wrote: > > > >>>> pass of_phandle_args dma_spec to dma_request_channel in > > > >>>> of_dma_simple_xlate, so the filter function could access of_node in > > > >>>> of_phandle_args. > > > >>>> > > > >>>> It also remove restriction of #dma-cells has to be one. > > > >>>> > > > >>>> Signed-off-by: Richard Zhao <rizhao@...dia.com> > > > >>>> --- > > > >>>> > > > >>>> drivers/dma/edma.c | 7 +++++-- > > > >>>> drivers/dma/of-dma.c | 10 ++++------ > > > >>>> drivers/dma/omap-dma.c | 6 ++++-- > > > >>>> 3 files changed, 13 insertions(+), 10 deletions(-) > > > >>> > > > >>> Hi Vinod, > > > >>> > > > >>> Can you please pick up this change? > > > >>> > > > >>> Hi Stephen, > > > >>> > > > >>> Can you please give a ack or reviewed-by etc? > > > >> > > > >> Hmm. Looking at the patch, I'm not sure it's right. > > > >> > > > >> This patch simply passes all the specfier args to the filter > > > >> function, and the code to check the equality of the of_node to the > > > >> filter args is still duplicated in each DMA driver. Instead, the DMA > > > >> core should be implementing the equality check, and only even calling > > > >> the driver-specific filter function for devices where the client's > > > >> phandle matches the DMA providing device's of_node handle. > > > > > > > > Filter function is called in dmaengine core code, independent of dt. > > > > > > The core code can still check if a dmaengine's driver was instantiated > > > from DT and take additional actions in that case. > > > > > > > And the reason why the driver has to write its own filter function is > > > > it has to store slave id there in its own way. > > > > > > I'm not saying don't call the driver's filter function, but rather that > > > the dmaengine core should perform the common checks before doing so. > > > > And it looks to me like the common case could even get rid of the driver's > > filter function: > > > > https://lkml.org/lkml/2013/5/15/270 > > https://lkml.org/lkml/2013/3/25/250 > > For general case, the slave id is not staticly bind to a specific channel. Certainly not in all cases, but I think it's common enough to deserve a specific helper function. -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists