On 19.07.2022 19:42, Oleksandr Tyshchenko wrote:
> --- a/xen/drivers/vpci/header.c
> +++ b/xen/drivers/vpci/header.c
> @@ -443,11 +443,27 @@ static int modify_bars(const struct pci_dev *pdev,
> uint16_t cmd, bool rom_only)
> return 0;
> }
>
> +/* TODO: Add proper emulation for all bits of the command register. */
> static void cf_check cmd_write(
> const struct pci_dev *pdev, unsigned int reg, uint32_t cmd, void *data)
> {
> uint16_t current_cmd = pci_conf_read16(pdev->sbdf, reg);
>
> + if ( !is_hardware_domain(pdev->domain) )
> + {
> + struct vpci_header *header = data;
> +
> + header->guest_cmd = cmd;
> +#ifdef CONFIG_HAS_PCI_MSI
> + if ( pdev->vpci->msi->enabled || pdev->vpci->msix->enabled )
> + /*
> + * Guest wants to enable INTx, but it can't be enabled
> + * if MSI/MSI-X enabled.
> + */
> + cmd |= PCI_COMMAND_INTX_DISABLE;
> +#endif
> + }
> +
> /*
> * Let Dom0 play with all the bits directly except for the memory
> * decoding one.
> @@ -464,6 +480,19 @@ static void cf_check cmd_write(
> pci_conf_write16(pdev->sbdf, reg, cmd);
> }
>
> +static uint32_t cf_check cmd_read(
> + const struct pci_dev *pdev, unsigned int reg, void *data)
> +{
> + if ( !is_hardware_domain(pdev->domain) )
> + {
> + struct vpci_header *header = data;
> +
> + return header->guest_cmd;
> + }
> +
> + return pci_conf_read16(pdev->sbdf, reg);
> +}
This function wants the same leading comment as cmd_write(). I also
think you better wouldn't give the guest the impression that r/o bits
can actually be written to (but getting this right may well fall
under the TODO).
Jan
