On 3/21/2024 10:23 AM, Jose Ignacio Tornos Martinez wrote: > Currently, this driver is not working when the device is handled in a > Virtual Machine (PCI pass-through), as it was already reported here: > https://lore.kernel.org/all/fc6bd06f-d52b-4dee-ab1b-4bb845cc0b95@xxxxxxxxxxx/T/ > Baochen Qiang focused the problem and described how to have it working > for a specific real MSI vector from host that needs to be used in VM too. > And this value, as it was commented, can change. > > The problem seems complex to me and I don't know if there is any easy way > to solve it. Meanwhile and using the information from Baochen Qiang, > since the use of VMs is very interesting for testing procedures, > I would like to just add this workaround that consists on adding a > parameter to pass the real MSI vector from host to the VM. In that way, > checking the 'lscpi' command output from host, it could be handled manually > or with some user tool in order to have the VM with the driver working. > Of course, if this parameter is not configured (zero value and default), > we will have the same behavior as always. > > Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@xxxxxxxxxx> > --- > drivers/net/wireless/ath/ath11k/pci.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/drivers/net/wireless/ath/ath11k/pci.c b/drivers/net/wireless/ath/ath11k/pci.c > index be9d2c69cc41..0e322956b10f 100644 > --- a/drivers/net/wireless/ath/ath11k/pci.c > +++ b/drivers/net/wireless/ath/ath11k/pci.c > @@ -31,6 +31,11 @@ > > #define TCSR_SOC_HW_SUB_VER 0x1910010 > > +static ulong ath11k_host_msi_addr = 0; > +module_param_named(host_msi_addr, ath11k_host_msi_addr, ulong, 0644); > +MODULE_PARM_DESC(host_msi_addr, > + "Workaround to configure the MSI address that is used from host in order to be used in VM"); > + > static const struct pci_device_id ath11k_pci_id_table[] = { > { PCI_VDEVICE(QCOM, QCA6390_DEVICE_ID) }, > { PCI_VDEVICE(QCOM, WCN6855_DEVICE_ID) }, > @@ -443,6 +448,18 @@ static int ath11k_pci_alloc_msi(struct ath11k_pci *ab_pci) > > ath11k_pci_msi_disable(ab_pci); > > + if (ath11k_host_msi_addr) { > + ab_pci->ab->pci.msi.ep_base_data = 0; > + ab->pci.msi.addr_hi = (u32)(ath11k_host_msi_addr >> 32); > + ab->pci.msi.addr_lo = (u32)(ath11k_host_msi_addr & 0xffffffff); > + > + ath11k_dbg(ab, ATH11K_DBG_PCI, "msi addr hi 0x%x lo 0x%x base data is %d\n", > + ab->pci.msi.addr_hi, > + ab->pci.msi.addr_lo, > + ab->pci.msi.ep_base_data); > + return 0; > + } > + > msi_desc = irq_get_msi_desc(ab_pci->pdev->irq); > if (!msi_desc) { > ath11k_err(ab, "msi_desc is NULL!\n"); > @@ -482,6 +499,9 @@ static int ath11k_pci_config_msi_data(struct ath11k_pci *ab_pci) > { > struct msi_desc *msi_desc; > > + if (ath11k_host_msi_addr) > + return 0; > + > msi_desc = irq_get_msi_desc(ab_pci->pdev->irq); > if (!msi_desc) { > ath11k_err(ab_pci->ab, "msi_desc is NULL!\n"); + kernel@xxxxxxxxxxx to make sure the Qualcomm VM experts are aware of this issue and to see if they have any additional suggestions.
