In current code, when guest does S3, virtio devices are reset due to the bit No_Soft_Reset is not set. After resetting, the display resources of virtio-gpu are destroyed, then the display can't come back and only show blank after resuming.
Implement No_Soft_Reset bit of PCI_PM_CTRL register, then guest can check this bit, if this bit is set, the devices resetting will not be done, and then the display can work after resuming. Signed-off-by: Jiqian Chen <jiqian.c...@amd.com> --- hw/virtio/virtio-pci.c | 38 +++++++++++++++++++++++++++++++++- include/hw/virtio/virtio-pci.h | 5 +++++ 2 files changed, 42 insertions(+), 1 deletion(-) diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index 1a7039fb0c68..daafda315f8c 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -2197,6 +2197,11 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp) pcie_cap_lnkctl_init(pci_dev); } + if (proxy->flags & VIRTIO_PCI_FLAG_PM_NO_SOFT_RESET) { + pci_set_word(pci_dev->config + pos + PCI_PM_CTRL, + PCI_PM_CTRL_NO_SOFT_RESET); + } + if (proxy->flags & VIRTIO_PCI_FLAG_INIT_PM) { /* Init Power Management Control Register */ pci_set_word(pci_dev->wmask + pos + PCI_PM_CTRL, @@ -2259,18 +2264,47 @@ static void virtio_pci_reset(DeviceState *qdev) } } +static bool device_no_need_reset(PCIDevice *dev) +{ + if (pci_is_express(dev)) { + uint16_t pmcsr; + + pmcsr = pci_get_word(dev->config + dev->exp.pm_cap + PCI_PM_CTRL); + /* + * When No_Soft_Reset bit is set and the device + * is in D3hot state, don't reset device + */ + if ((pmcsr & PCI_PM_CTRL_NO_SOFT_RESET) && + (pmcsr & PCI_PM_CTRL_STATE_MASK) == 3) { + return true; + } + } + + return false; +} + static void virtio_pci_bus_reset_hold(Object *obj) { PCIDevice *dev = PCI_DEVICE(obj); DeviceState *qdev = DEVICE(obj); + if (device_no_need_reset(dev)) { + return; + } + virtio_pci_reset(qdev); if (pci_is_express(dev)) { + uint16_t val = 0; + VirtIOPCIProxy *proxy = VIRTIO_PCI(dev); + pcie_cap_deverr_reset(dev); pcie_cap_lnkctl_reset(dev); - pci_set_word(dev->config + dev->exp.pm_cap + PCI_PM_CTRL, 0); + if (proxy->flags & VIRTIO_PCI_FLAG_PM_NO_SOFT_RESET) { + val |= PCI_PM_CTRL_NO_SOFT_RESET; + } + pci_set_word(dev->config + dev->exp.pm_cap + PCI_PM_CTRL, val); } } @@ -2297,6 +2331,8 @@ static Property virtio_pci_properties[] = { VIRTIO_PCI_FLAG_INIT_LNKCTL_BIT, true), DEFINE_PROP_BIT("x-pcie-pm-init", VirtIOPCIProxy, flags, VIRTIO_PCI_FLAG_INIT_PM_BIT, true), + DEFINE_PROP_BIT("x-pcie-pm-no-soft-reset", VirtIOPCIProxy, flags, + VIRTIO_PCI_FLAG_PM_NO_SOFT_RESET_BIT, false), DEFINE_PROP_BIT("x-pcie-flr-init", VirtIOPCIProxy, flags, VIRTIO_PCI_FLAG_INIT_FLR_BIT, true), DEFINE_PROP_BIT("aer", VirtIOPCIProxy, flags, diff --git a/include/hw/virtio/virtio-pci.h b/include/hw/virtio/virtio-pci.h index 59d88018c16a..9e67ba38c748 100644 --- a/include/hw/virtio/virtio-pci.h +++ b/include/hw/virtio/virtio-pci.h @@ -43,6 +43,7 @@ enum { VIRTIO_PCI_FLAG_INIT_FLR_BIT, VIRTIO_PCI_FLAG_AER_BIT, VIRTIO_PCI_FLAG_ATS_PAGE_ALIGNED_BIT, + VIRTIO_PCI_FLAG_PM_NO_SOFT_RESET_BIT, }; /* Need to activate work-arounds for buggy guests at vmstate load. */ @@ -79,6 +80,10 @@ enum { /* Init Power Management */ #define VIRTIO_PCI_FLAG_INIT_PM (1 << VIRTIO_PCI_FLAG_INIT_PM_BIT) +/* Init The No_Soft_Reset bit of Power Management */ +#define VIRTIO_PCI_FLAG_PM_NO_SOFT_RESET \ + (1 << VIRTIO_PCI_FLAG_PM_NO_SOFT_RESET_BIT) + /* Init Function Level Reset capability */ #define VIRTIO_PCI_FLAG_INIT_FLR (1 << VIRTIO_PCI_FLAG_INIT_FLR_BIT) -- 2.34.1