[+cc linux-pci, Xilinx and DMA engine folks] I'm not sure what to do with this report. It mentions "vivado" and xilinx_ps_pcie_platform.c, neither of which seems to be in mainline or linux-next. A Google search suggests that Vivado is a Xilinx product; maybe this bug report should be directed there? On Fri, Apr 26, 2019 at 7:09 AM <bugzilla-daemon@xxxxxxxxxxxxxxxxxxx> wrote: > > https://bugzilla.kernel.org/show_bug.cgi?id=203435 > > Bug ID: 203435 > Summary: Xilinx pcie endpoint DMA not functional for ZynqMP PS > AXI-PXI DMA endpoint > Product: Drivers > Version: 2.5 > Kernel Version: 4.14.0 > Hardware: Other > OS: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: PCI > Assignee: drivers_pci@xxxxxxxxxxxxxxxxxxxx > Reporter: dtyree@xxxxxxxxxxxxxxx > Regression: No > > The ps_pcie_dma-1.00.a driver does not work as an endpoint. I'd be happy to > help fix/enable/test this out, but I do not understand what the intent was. > > The rootdma option is the only one allowed / documented through device-tree and > kernel docs. It does not cover the epdma branches in the code that require that > drivers/dma/xilinx/xilinx_ps_pcie_platform.c:18:#define PLATFORM_DRIVER_NAME > "ps_pcie_pform_dma" > > be available. I am not sure if this was intended to be the endpoint. > > The vivado build for the pcie endpoint will not enable the endpoint DMA > channels. I would expect that to be done through device-tree/PCIe BAR > configuration reads (for sizes) to set up the channels, but I can't find > anything that may other than the mystery of epdma with PLATFORM_DRIVER_NAME. > > Because the fsbl does not enable the AXI-DMA the rootdma channel enable check > fails on line xilinx_ps_pcie_platform.c:1832 > channel->chan_base = > (struct DMA_ENGINE_REGISTERS *)((__force char *)(xdev->reg_base) + > (channel_number * DMA_CHANNEL_REGS_SIZE)); > > if (((channel->chan_base->dma_channel_status) & > DMA_STATUS_DMA_PRES_BIT) == 0) { > dev_err(&platform_dev->dev, > "Hardware reports channel not present\n"); > return -ENOTSUPP; > } > > Is there a different way to access use the PS AXI-PCIe DMA? > > Can anyone offer some advice? Have I misunderstood the dis-functionality of the > epdma -vs- rootdma branching? > > Thanks
