On Wed, Jan 18, 2023 at 08:36:00PM -0500, Tianfei Zhang wrote: > Implement the image_load and available_images callback functions > for fpgahp driver. This patch leverages some APIs from pciehp > driver to implement the device reconfiguration below the PCI hotplug > bridge. > > Here are the steps for a process of image load. > 1. remove all PFs and VFs except the PF0. > 2. remove all non-reserved devices of PF0. > 3. trigger a image load via BMC. > 4. disable the link of the hotplug bridge. > 5. remove all reserved devices under PF0 and PCI devices > below the hotplug bridge. > 6. wait for image load done via BMC, e.g. 10s. > 7. re-enable the link of the hotplug bridge. > 8. re-enumerate PCI devices below the hotplug bridge. > > Signed-off-by: Tianfei Zhang <tianfei.zhang@xxxxxxxxx> > --- > Documentation/ABI/testing/sysfs-driver-fpgahp | 21 ++ > MAINTAINERS | 1 + > drivers/pci/hotplug/fpgahp.c | 179 ++++++++++++++++++ > 3 files changed, 201 insertions(+) > create mode 100644 Documentation/ABI/testing/sysfs-driver-fpgahp > > diff --git a/Documentation/ABI/testing/sysfs-driver-fpgahp b/Documentation/ABI/testing/sysfs-driver-fpgahp > new file mode 100644 > index 000000000000..8d4b1bfc4012 > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-driver-fpgahp > @@ -0,0 +1,21 @@ > +What: /sys/bus/pci/slots/X-X/available_images > +Date: May 2023 > +KernelVersion: 6.3 > +Contact: Tianfei Zhang <tianfei.zhang@xxxxxxxxx> > +Description: Read-only. This file returns a space separated list of > + key words that may be written into the image_load file > + described below. These keywords decribe an FPGA, BMC, > + or firmware image in FLASH or EEPROM storage that may > + be loaded. No, sysfs is "one value per file", why is this a list? And what exactly defines the values in this list? > + > +What: /sys/bus/pci/slots/X-X/image_load > +Date: May 2023 > +KernelVersion: 6.3 > +Contact: Tianfei Zhang <tianfei.zhang@xxxxxxxxx> > +Description: Write-only. A key word may be written to this file to > + trigger a new image loading of an FPGA, BMC, or firmware > + image from FLASH or EEPROM. Refer to the available_images > + file for a list of supported key words for the underlying > + device. > + Writing an unsupported string to this file will result in > + EINVAL being returned. Why is this a separate file from the "read the list" file? That feels wrong. thanks, greg k-h
