On 03.11.2021 11:24, Oleksandr Andrushchenko wrote:
> On 03.11.21 11:49, Jan Beulich wrote:
>> Aiui you want to prevent the guest from clearing the bit if either
>> MSI or MSI-X are in use. Symmetrically, when the guest enables MSI
>> or MSI-X, you will want to force the bit set (which may well be in
>> a separate, future patch).
> static uint32_t emulate_cmd_reg(const struct pci_dev *pdev, uint32_t cmd)
> {
> /* TODO: Add proper emulation for all bits of the command register. */
>
> if ( (cmd & PCI_COMMAND_INTX_DISABLE) == 0 )
> {
> /* Guest wants to enable INTx. It can't be enabled if MSI/MSI-X
> enabled. */
> #ifdef CONFIG_HAS_PCI_MSI
> if ( pdev->vpci->msi->enabled )
> cmd |= PCI_COMMAND_INTX_DISABLE;
> #endif
> }
>
> return cmd;
> }
>
> Is this what you mean?
Something along these lines, yes. I'd omit the outer if() for clarity /
brevity.
Jan
