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

[Max Zhen]

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;
> > +     }