Re: [PATCH Xilinx Alveo 7/8] fpga: xrt: Alveo management physical function driver

Max Zhen
2020-12-04T04:41:33Z

Hi Yilun,

On 12/1/20 7:00 PM, Xu Yilun wrote:
>
>
>> +static int xmgmt_main_event_cb(struct platform_device *pdev,
>> + enum xrt_events evt, void *arg)
>> +{
>> + struct xmgmt_main *xmm = platform_get_drvdata(pdev);
>> + struct xrt_event_arg_subdev *esd = (struct xrt_event_arg_subdev *)arg;
>> + enum xrt_subdev_id id;
>> + int instance;
>> + size_t fwlen;
>> +
>> + switch (evt) {
>> + case XRT_EVENT_POST_CREATION: {
>> + id = esd->xevt_subdev_id;
>> + instance = esd->xevt_subdev_instance;
>> + xrt_info(pdev, "processing event %d for (%d, %d)",
>> + evt, id, instance);
>> +
>> + if (id == XRT_SUBDEV_GPIO)
>> + xmm->gpio_ready = true;
>> + else if (id == XRT_SUBDEV_QSPI)
>> + xmm->flash_ready = true;
>> + else
>> + BUG_ON(1);
>> +
>> + if (xmm->gpio_ready && xmm->flash_ready) {
>> + int rc;
>> +
>> + rc = load_firmware_from_disk(pdev, &xmm->firmware_blp,
>> + &fwlen);
>> + if (rc != 0) {
>> + rc = load_firmware_from_flash(pdev,
>> + &xmm->firmware_blp, &fwlen);
>
> I'm curious that before the shell metadata is loaded, how the QSPI
> subdev is enumerated and get to work? The QSPI DT info itself is
> stored in metadata, is it?

No, it is not from the shell metadata. The QSPI subdev info is
discovered from a rom located on the PCIE BAR pointed to by VSEC cap
found in config space.

>
> I didn't find the creation of leaf platform devices, maybe I can find
> the answer in the missing Patch #5?

Leaf driver is children of partition driver. They are created in
xrt_part_create_leaves() in xrt-partition.c.

Thanks,
Max

>
> Thanks,
> Yilun
>
>> + }
>> + if (rc == 0 && is_valid_firmware(pdev,
>> + xmm->firmware_blp, fwlen))
>> + (void) xmgmt_create_blp(xmm);
>> + else
>> + xrt_err(pdev,
>> + "failed to find firmware, giving up");
>> + xmm->evt_hdl = NULL;
>> + }
>> + break;
>> + }