> From: Scott Wood > > On 06/07/2016 02:06 AM, Liu Gang wrote: > > The 'dma-coherent' indicates that the hardware IP block can ensure the > > coherency of the data transferred from/to the IP block. This can avoid > > the software cache flush/invalid actions, and improve the performance > > significantly. > > > > The PCI IP block of ls1043a has this capability, so adding this > > feature to improve the PCI performance. > > > > Signed-off-by: Liu Gang <Gang.Liu@xxxxxxx> > > --- > > arch/arm64/boot/dts/freescale/fsl-ls1043a.dtsi | 3 +++ > > 1 file changed, 3 insertions(+) > > Why not ls2080a as well? [Liu Gang] ls2080 should also include this property, we can add it after verification. > What about non-PCI devices? > > Pretty much everything on these chips should be coherent as long as it's > properly configured. [Liu Gang] you are right. For the layerscape platforms including CCI or CCN internal bus, theoretically, pretty much IP blocks (PCI/non-PCI) should be coherent. But this depends on the properly hardware and software configurations. (ls1012a PCI devices cannot implement the coherent duo to hardware issue) So I think we'd better to add this property after each IP block's verification. Thanks! Liu Gang > > -Scott -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
