On Tue, Sep 09, 2025 at 09:43:02AM -0500, Lucas De Marchi wrote:
On Tue, Sep 09, 2025 at 04:50:41AM +0000, Usyskin, Alexander wrote:
+static int mei_lb_component_match(struct device *dev, int subcomponent,
+ void *data)
+{
+ /*
+ * This function checks if requester is Intel %PCI_CLASS_DISPLAY_VGA
or
+ * %PCI_CLASS_DISPLAY_OTHER device, and checks if the requester is
the
+ * grand parent of mei_if i.e. late bind MEI device
+ */
+ struct device *base = data;
+ struct pci_dev *pdev;
+
+ if (!dev)
+ return 0;
+
+ if (!dev_is_pci(dev))
+ return 0;
+
+ pdev = to_pci_dev(dev);
+
+ if (pdev->vendor != PCI_VENDOR_ID_INTEL)
+ return 0;
+
+ if (pdev->class != (PCI_CLASS_DISPLAY_VGA << 8) &&
+ pdev->class != (PCI_CLASS_DISPLAY_OTHER << 8))
this doesn't seem right, we should allow other PCI classes. AFAICS this
check could just be removed and just leave the INTEL_COMPONENT_LB below
to protect for component match
Lucas De Marchi
The subcomponent is unique only in its own instance of the component framework.
Or I'm wrong here?
We have to ensure that we have Intel display device, not any other device to
subcomponent check to work correctly.
We are matching by child-parent relationship + the component id. So you
have both the mei device and another pci device that added that specific
subcomponent and both need to have a common parent. Thinking about
another device that would match the parent-child relationship: audio,
but audio doesn't add that.
what scenario would cause a false match that I'm not seeing?
so, I doesn't seem it would fail any, but it's fine as a sanity check.
This is in fact very similar to mei_pxp_component_match(). If we are
going to remove the display check, it could be done later on top, making
sure not to match what it shouldn't.
So, this looks good to me. I tested this on a Battlemage card
it's correclty loading the firmware:
xe 0000:03:00.0: [drm:xe_late_bind_init [xe]] Request late binding
firmware xe/fan_control_8086_e20b_8086_1100.bin
xe 0000:03:00.0: [drm] Using fan_control firmware from
xe/fan_control_8086_e20b_8086_1100.bin version 203.0.0.0
...
mei_lb xe.mei-gscfi.768-e2c2afa2-3817-4d19-9d95-06b16b588a5d: bound
0000:03:00.0 (ops xe_late_bind_component_ops [xe])
xe 0000:03:00.0: [drm:xe_late_bind_work [xe]] Load fan_control firmware
xe 0000:03:00.0: [drm:xe_late_bind_work [xe]] Load fan_control firmware
successful
Reviewed-by: Lucas De Marchi <lucas.demar...@intel.com>
Greg, does this look ok to you now for us to merge through drm?
thanks
Lucas De Marchi
Lucas De Marchi
