On Thu, May 18, 2017 at 02:13:59PM +0100, Jon Medhurst (Tixy) wrote: > On Thu, 2017-05-18 at 13:23 +0100, Robin Murphy wrote: > > The IOMMU-backed DMA API support has now been in place for a while and > > proven stable, so there's no real need to keep most of Juno's SMMUs > > disabled. The USB, HDLCDs, and CoreSight ETR all just need to map RAM > > buffers for DMA - enabling their SMMUs obviates CPU bounce buffering for > > USB's streaming DMA to the upper memory bank, and lets the other two > > allocate their relatively large coherent buffers without pressuring CMA. > > > > Some more software work is still needed for the DMA-330 and PCIe before > > those can accommodate SMMU translation correctly in all cases, so we > > leave those alone for now. > > > > Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx> > > --- > > For those that don't already know, status = "disabled" for smmu is > broken in Linux 4.12-rc1, and this fixes it... > https://lkml.org/lkml/2017/5/17/344 Hey, fancy that!! I was just starting to wonder why some of my "disabled" nodes in the juno-base.dts were showing as "okay". :) Thanks Tixy for the tip! Liviu > > > arch/arm64/boot/dts/arm/juno-base.dtsi | 4 ---- > > 1 file changed, 4 deletions(-) > > > > diff --git a/arch/arm64/boot/dts/arm/juno-base.dtsi b/arch/arm64/boot/dts/arm/juno-base.dtsi > > index bfe7d683a42e..02aea43238fc 100644 > > --- a/arch/arm64/boot/dts/arm/juno-base.dtsi > > +++ b/arch/arm64/boot/dts/arm/juno-base.dtsi > > @@ -53,7 +53,6 @@ > > #global-interrupts = <1>; > > dma-coherent; > > power-domains = <&scpi_devpd 0>; > > - status = "disabled"; > > }; > > > > gic: interrupt-controller@2c010000 { > > @@ -546,7 +545,6 @@ > > <GIC_SPI 99 IRQ_TYPE_LEVEL_HIGH>; > > #iommu-cells = <1>; > > #global-interrupts = <1>; > > - status = "disabled"; > > }; > > > > smmu_hdlcd0: iommu@7fb20000 { > > @@ -556,7 +554,6 @@ > > <GIC_SPI 97 IRQ_TYPE_LEVEL_HIGH>; > > #iommu-cells = <1>; > > #global-interrupts = <1>; > > - status = "disabled"; > > }; > > > > smmu_usb: iommu@7fb30000 { > > @@ -567,7 +564,6 @@ > > #iommu-cells = <1>; > > #global-interrupts = <1>; > > dma-coherent; > > - status = "disabled"; > > }; > > > > dma@7ff00000 { -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯ -- 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
