From: Oleksandr Andrushchenko <[email protected]> Add basic emulation support for guests. At the moment only emulate PCI_COMMAND_INTX_DISABLE bit, the rest is not emulated yet and left as TODO.
Signed-off-by: Oleksandr Andrushchenko <[email protected]> Reviewed-by: Michal Orzel <[email protected]> --- New in v2 --- xen/drivers/vpci/header.c | 35 ++++++++++++++++++++++++++++++++--- 1 file changed, 32 insertions(+), 3 deletions(-) diff --git a/xen/drivers/vpci/header.c b/xen/drivers/vpci/header.c index f23c956cde6c..754aeb5a584f 100644 --- a/xen/drivers/vpci/header.c +++ b/xen/drivers/vpci/header.c @@ -451,6 +451,32 @@ static void cmd_write(const struct pci_dev *pdev, unsigned int reg, pci_conf_write16(pdev->sbdf, reg, cmd); } +static void guest_cmd_write(const struct pci_dev *pdev, unsigned int reg, + uint32_t cmd, void *data) +{ + /* 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: + * - host has INTx disabled + * - MSI/MSI-X enabled + */ + if ( pdev->vpci->msi->enabled ) + cmd |= PCI_COMMAND_INTX_DISABLE; + else + { + uint16_t current_cmd = pci_conf_read16(pdev->sbdf, reg); + + if ( current_cmd & PCI_COMMAND_INTX_DISABLE ) + cmd |= PCI_COMMAND_INTX_DISABLE; + } + } + + cmd_write(pdev, reg, cmd, data); +} + static void bar_write(const struct pci_dev *pdev, unsigned int reg, uint32_t val, void *data) { @@ -598,9 +624,12 @@ static int add_bar_handlers(const struct pci_dev *pdev, bool is_hwdom) struct vpci_bar *bars = header->bars; int rc; - /* Setup a handler for the command register: same for hwdom and guests. */ - rc = vpci_add_register(pdev->vpci, vpci_hw_read16, cmd_write, PCI_COMMAND, - 2, header); + if ( is_hwdom ) + rc = vpci_add_register(pdev->vpci, vpci_hw_read16, cmd_write, + PCI_COMMAND, 2, header); + else + rc = vpci_add_register(pdev->vpci, vpci_hw_read16, guest_cmd_write, + PCI_COMMAND, 2, header); if ( rc ) return rc; -- 2.25.1
