[PATCH v3] Axi-usb: Add support for 64-bit addressing.

Arnd Bergmann
2016-05-24T08:50:37Z

On Tuesday, May 24, 2016 10:51:08 AM CEST Nava kishore Manne wrote:
> diff --git a/Documentation/devicetree/bindings/usb/udc-xilinx.txt b/Documentation/devicetree/bindings/usb/udc-xilinx.txt
> index 47b4e39..09df757 100644
> --- a/Documentation/devicetree/bindings/usb/udc-xilinx.txt
> +++ b/Documentation/devicetree/bindings/usb/udc-xilinx.txt
> @@ -1,18 +1,23 @@
> Xilinx USB2 device controller
>
> Required properties:
> -- compatible : Should be "xlnx,usb2-device-4.00.a"
> +- compatible : Should be "xlnx,usb2-device-4.00.a" or
> + "xlnx,usb2-device-5.00"
> - reg : Physical base address and size of the USB2
> device registers map.
> - interrupts : Should contain single irq line of USB2 device
> controller
> - xlnx,has-builtin-dma : if DMA is included
> +- dma-ranges : Should be as the following
> + <child-bus-address, parent-bus-address, length>

A USB host should not have any children that are DMA capable, I think, so this
property doesn't make sense here. It should be part of the parent bus.

> +- xlnx,addrwidth : Should be the dma addressing size in bits(ex: 64 bits)

I'm still unconvinced about the property definition here. What are the possible
options for the IP block? I don't think I ever saw a reply from you to my earlier
questions.

> @@ -214,6 +223,20 @@ static const struct usb_endpoint_descriptor config_bulk_out_desc = {
> .wMaxPacketSize = cpu_to_le16(EP0_MAX_PACKET),
> };
>
> +/**
> + * xudc_write64 - write 64bit value to device registers
> + * @addr: base addr of device registers
> + * @offset: register offset
> + * @val: data to be written
> + **/
> +static void xudc_write64(struct xusb_ep *ep, u32 offset, u64 val)
> +{
> + struct xusb_udc *udc = ep->udc;
> +
> + udc->write_fn(udc->addr, offset, lower_32_bits(val));
> + udc->write_fn(udc->addr, offset+0x04, upper_32_bits(val));
> +}
> +
> /**
> * xudc_write32 - little endian write to device registers
> * @addr: base addr of device registers
> @@ -330,8 +353,13 @@ static int xudc_start_dma(struct xusb_ep *ep, dma_addr_t src,
> * destination registers and then set the length
> * into the DMA length register.
> */
> - udc->write_fn(udc->addr, XUSB_DMA_DSAR_ADDR_OFFSET, src);
> - udc->write_fn(udc->addr, XUSB_DMA_DDAR_ADDR_OFFSET, dst);
> + if (udc->dma_addrwidth > 32) {
> + xudc_write64(ep, XUSB_DMA_DSAR_ADDR_OFFSET_LSB, src);
> + xudc_write64(ep, XUSB_DMA_DDAR_ADDR_OFFSET_LSB, dst);
> + } else {
> + udc->write_fn(udc->addr, XUSB_DMA_DSAR_ADDR_OFFSET, src);
> + udc->write_fn(udc->addr, XUSB_DMA_DDAR_ADDR_OFFSET, dst);
> + }
> udc->write_fn(udc->addr, XUSB_DMA_LENGTH_OFFSET, length);
>

This looks good.

Arnd