In pre-launched VM the GPA of vmsix BAR which is used for vmsix
over msi is calculated/allocated by acrn-config tool. The GPA
needs to be assigned to vdev when vdev is initialized. The
assignment is only needed for pre-launched VM. For SOS kernel
will reprogram the Bar base when startup. For post-launched VM
the Bar GPA will be assigned by device model via hypercall.
Tracked-On: #5316
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
When init_vmsix_on_msi is called during the initialization of a pt
device, the vmsix bar used for vmsix over msi is just created. No
mapping/unmapping is done and pci_vdev_write_vbar should be called
instead of vdev_pt_write_vbar at the time. Currently the Bar mapping
is delayed till OS sizing the Bar. Backup vbar base_gpa to mmio_gpa
is not required here becuase it will be done later when Bar mapping.
Tracked-On: #5316
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
Some passthrough devices require multiple MSI vectors, but don't
support MSI-X. In meanwhile, Linux kernel doesn't support continuous
vector allocation.
On native platform, this issue can be mitigated by IOMMU via interrupt
remapping. However, on ACRN, there is no vIOMMU.
vMSI-X on MSI emulation is one solution to mitigate this problem on ACRN.
This patch adds MSI-X emulation on MSI capability.
For the device needs to do MSI-X emulation, HV will hide MSI capability
and present MSI-X capability to guest.
The guest driver may need to modify to reqeust MSI-X vector.
For example:
ret = pci_alloc_irq_vectors(pdev, 1, STMMAC_MSI_VEC_MAX,
- PCI_IRQ_MSI);
+ PCI_IRQ_MSI | PCI_IRQ_MSIX);
To enable MSI-X emulation, the device should:
- 1. The device should be in vmsix_on_msi_devs array.
- 2. Support MSI, but don't support MSI-X.
- 3. MSI capability should support per-vector mask.
- 4. The device should have an unused BAR.
- 5. The device driver should not rely on PBA for functionality.
Tracked-On: #4831
Signed-off-by: Binbin Wu <binbin.wu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
