Re: [PATCH 00/21] SMMU enablement for NXP LS1043A and LS1046A
From: Robin Murphy <robin.murphy@arm.com>
Date: 2018-09-19 14:37:18
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On 19/09/18 15:18, Laurentiu Tudor wrote:
Hi Robin, On 19.09.2018 16:25, Robin Murphy wrote:quoted
Hi Laurentiu, On 19/09/18 13:35, laurentiu.tudor@nxp.com wrote:quoted
From: Laurentiu Tudor <laurentiu.tudor@nxp.com> This patch series adds SMMU support for NXP LS1043A and LS1046A chips and consists mostly in important driver fixes and the required device tree updates. It touches several subsystems and consists of three main parts: - changes in soc/drivers/fsl/qbman drivers adding iommu mapping of reserved memory areas, fixes and defered probe support - changes in drivers/net/ethernet/freescale/dpaa_eth drivers consisting in misc dma mapping related fixes and probe ordering - addition of the actual arm smmu device tree node together with various adjustments to the device trees Performance impact Running iperf benchmarks in a back-to-back setup (both sides having smmu enabled) on a 10GBps port show an important networking performance degradation of around %40 (9.48Gbps linerate vs 5.45Gbps). If you need performance but without SMMU support you can use "iommu.passthrough=1" to disable SMMU. USB issue and workaround There's a problem with the usb controllers in these chips generating smaller, 40-bit wide dma addresses instead of the 48-bit supported at the smmu input. So you end up in a situation where the smmu is mapped with 48-bit address translations, but the device generates transactions with clipped 40-bit addresses, thus smmu context faults are triggered. I encountered a similar situation for mmc that I managed to fix in software [1] however for USB I did not find a proper place in the code to add a similar fix. The only workaround I found was to add this kernel parameter which limits the usb dma to 32-bit size: "xhci-hcd.quirks=0x800000". This workaround if far from ideal, so any suggestions for a code based workaround in this area would be greatly appreciated.If you have a nominally-64-bit device with a narrower-than-the-main-interconnect link in front of it, that should already be fixed in 4.19-rc by bus_dma_mask picking up DT dma-ranges, provided the interconnect hierarchy can be described appropriately (or at least massaged sufficiently to satisfy the binding), e.g.: / { ... soc { ranges; dma-ranges = <0 0 10000 0>; dev_48bit { ... }; periph_bus { ranges; dma-ranges = <0 0 100 0>; dev_40bit { ... }; }; }; }; and if that fails to work as expected (except for PCI hosts where handling dma-ranges properly still needs sorting out), please do let us know ;)Just to confirm, Is this [1] the change I was supposed to test?
Not quite - dma-ranges is only valid for nodes representing a bus, so putting it directly in the USB device nodes doesn't work (FWIW that's why PCI is broken, because the parser doesn't expect the bus-as-leaf-node case). That's teh point of that intermediate simple-bus node represented by "periph_bus" in my example (sorry, I should have put compatibles in to make it clearer) - often that's actually true to life (i.e. "soc" is something like a CCI and "periph_bus" is something like an AXI NIC gluing a bunch of lower-bandwidth DMA masters to one of the CCI ports) but at worst it's just a necessary evil to make the binding happy (if it literally only represents the point-to-point link between the device master port and interconnect slave port).
Because if so, I'm still seeing context faults [2] with what looks like clipped to 40-bits addresses. :-( IIRC, the usb subsystem explicitly set 64-bit dma masks which in turn will be limited to the SMMU input size of 48-bit. Won't that overwrite the default dma mask derived from dma-ranges?
Indeed it will, but those default masks were effectively only ever a best-effort thing anyway - it's an ease-of-implementation detail that bus_dma_mask is not currently reflected in the device masks, although we may eventually change that; the crucial part is that the DMA ops implementations know about it and should now enforce it properly regardless of whether drivers set something wider. Robin.
quoted hunk ↗ jump to hunk
--- Best Regards, Laurentiu [1] -----------------------------------------------------------------diff --git a/arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsib/arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsi index 3bdea0470f69..a214c3df37fd 100644--- a/arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsi +++ b/arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsi@@ -612,6 +612,7 @@ compatible = "snps,dwc3"; reg = <0x0 0x2f00000 0x0 0x10000>; interrupts = <GIC_SPI 60 IRQ_TYPE_LEVEL_HIGH>; + dma-ranges = <0x0 0x0 0x0 0x0 0x100 0x00000000>; dr_mode = "host"; snps,quirk-frame-length-adjustment = <0x20>; snps,dis_rxdet_inp3_quirk;@@ -621,6 +622,7 @@ compatible = "snps,dwc3"; reg = <0x0 0x3000000 0x0 0x10000>; interrupts = <GIC_SPI 61 IRQ_TYPE_LEVEL_HIGH>; + dma-ranges = <0x0 0x0 0x0 0x0 0x100 0x00000000>; dr_mode = "host"; snps,quirk-frame-length-adjustment = <0x20>; snps,dis_rxdet_inp3_quirk;@@ -630,6 +632,7 @@ compatible = "snps,dwc3"; reg = <0x0 0x3100000 0x0 0x10000>; interrupts = <GIC_SPI 63 IRQ_TYPE_LEVEL_HIGH>; + dma-ranges = <0x0 0x0 0x0 0x0 0x100 0x00000000>; dr_mode = "host"; snps,quirk-frame-length-adjustment = <0x20>; snps,dis_rxdet_inp3_quirk;[2] ----------------------------------------------------------------- [ 2.090577] xhci-hcd xhci-hcd.0.auto: xHCI Host Controller [ 2.096064] xhci-hcd xhci-hcd.0.auto: new USB bus registered, assigned bus number 2 [ 2.103720] xhci-hcd xhci-hcd.0.auto: Host supports USB 3.0 SuperSpeed [ 2.110346] arm-smmu 9000000.iommu: Unhandled context fault: fsr=0x402, iova=0xffffffb000, fsynr=0x1b0000, cb=3 [ 2.120449] usb usb2: We don't know the algorithms for LPM for this host, disabling LPM. [ 2.128717] hub 2-0:1.0: USB hub found [ 2.132473] hub 2-0:1.0: 1 port detected [ 2.136527] xhci-hcd xhci-hcd.1.auto: xHCI Host Controller [ 2.142014] xhci-hcd xhci-hcd.1.auto: new USB bus registered, assigned bus number 3 [ 2.149747] xhci-hcd xhci-hcd.1.auto: hcc params 0x0220f66d hci version 0x100 quirks 0x0000000002010010 [ 2.159149] xhci-hcd xhci-hcd.1.auto: irq 50, io mem 0x03000000 [ 2.165284] hub 3-0:1.0: USB hub found [ 2.169039] hub 3-0:1.0: 1 port detected [ 2.173051] xhci-hcd xhci-hcd.1.auto: xHCI Host Controller [ 2.178536] xhci-hcd xhci-hcd.1.auto: new USB bus registered, assigned bus number 4 [ 2.186193] xhci-hcd xhci-hcd.1.auto: Host supports USB 3.0 SuperSpeed [ 2.192809] arm-smmu 9000000.iommu: Unhandled context fault: fsr=0x402, iova=0xffffffb000, fsynr=0x1f0000, cb=4 [ 2.192822] usb usb4: We don't know the algorithms for LPM for this host, disabling LPM. [ 2.211141] hub 4-0:1.0: USB hub found [ 2.214896] hub 4-0:1.0: 1 port detected [ 2.218935] xhci-hcd xhci-hcd.2.auto: xHCI Host Controller [ 2.224425] xhci-hcd xhci-hcd.2.auto: new USB bus registered, assigned bus number 5 [ 2.232153] xhci-hcd xhci-hcd.2.auto: hcc params 0x0220f66d hci version 0x100 quirks 0x0000000002010010 [ 2.241562] xhci-hcd xhci-hcd.2.auto: irq 51, io mem 0x03100000 [ 2.247694] hub 5-0:1.0: USB hub found [ 2.251449] hub 5-0:1.0: 1 port detected [ 2.255458] xhci-hcd xhci-hcd.2.auto: xHCI Host Controller [ 2.260945] xhci-hcd xhci-hcd.2.auto: new USB bus registered, assigned bus number 6 [ 2.268601] xhci-hcd xhci-hcd.2.auto: Host supports USB 3.0 SuperSpeed [ 2.275218] arm-smmu 9000000.iommu: Unhandled context fault: fsr=0x402, iova=0xffffffb000, fsynr=0x110000, cb=5 [ 2.275230] usb usb6: We don't know the algorithms for LPM for this host, disabling LPM.quoted
quoted
The patch set is based on net-next so, if generally agreed, I'd suggest to get the patches through the netdev tree after getting all the Acks. [1] https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.kernel.org%2Fpatch%2F10506627%2F&data=02%7C01%7Claurentiu.tudor%40nxp.com%7C63c4e1dfc126488eb4ba08d61e336607%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C636729603447603039&sdata=XhjOX9aLgoe%2BSTBgZztv6zCz0vMebSXW%2Fnb2QcD5shY%3D&reserved=0 Laurentiu Tudor (21): soc/fsl/qman: fixup liodns only on ppc targets soc/fsl/bman: map FBPR area in the iommu soc/fsl/qman: map FQD and PFDR areas in the iommu soc/fsl/qman-portal: map CENA area in the iommu soc/fsl/qbman: add APIs to retrieve the probing status soc/fsl/qman_portals: defer probe after qman's probe soc/fsl/bman_portals: defer probe after bman's probe soc/fsl/qbman_portals: add APIs to retrieve the probing status fsl/fman: backup and restore ICID registers fsl/fman: add API to get the device behind a fman port dpaa_eth: defer probing after qbman dpaa_eth: base dma mappings on the fman rx port dpaa_eth: fix iova handling for contiguous frames dpaa_eth: fix iova handling for sg frames dpaa_eth: fix SG frame cleanup arm64: dts: ls1046a: add smmu node arm64: dts: ls1043a: add smmu node arm64: dts: ls104xa: set mask to drop TBU ID from StreamID arm64: dts: ls104x: add missing dma ranges property arm64: dts: ls104x: add iommu-map to pci controllers arm64: dts: ls104x: make dma-coherent global to the SoC .../arm64/boot/dts/freescale/fsl-ls1043a.dtsi | 52 ++++++- .../arm64/boot/dts/freescale/fsl-ls1046a.dtsi | 48 +++++++ .../net/ethernet/freescale/dpaa/dpaa_eth.c | 136 ++++++++++++------ drivers/net/ethernet/freescale/fman/fman.c | 35 ++++- drivers/net/ethernet/freescale/fman/fman.h | 4 + .../net/ethernet/freescale/fman/fman_port.c | 14 ++ .../net/ethernet/freescale/fman/fman_port.h | 2 + drivers/soc/fsl/qbman/bman_ccsr.c | 23 +++ drivers/soc/fsl/qbman/bman_portal.c | 20 ++- drivers/soc/fsl/qbman/qman_ccsr.c | 30 ++++ drivers/soc/fsl/qbman/qman_portal.c | 35 +++++ include/soc/fsl/bman.h | 16 +++ include/soc/fsl/qman.h | 17 +++ 13 files changed, 379 insertions(+), 53 deletions(-)