diff options
| -rw-r--r-- | drivers/vfio/pci/vfio_pci_config.c | 41 |
1 files changed, 38 insertions, 3 deletions
diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c index f1dde2c0fe99..964ff22bf281 100644 --- a/drivers/vfio/pci/vfio_pci_config.c +++ b/drivers/vfio/pci/vfio_pci_config.c @@ -587,12 +587,46 @@ static int __init init_pci_cap_basic_perm(struct perm_bits *perm) return 0; } +static int vfio_pm_config_write(struct vfio_pci_device *vdev, int pos, + int count, struct perm_bits *perm, + int offset, __le32 val) +{ + count = vfio_default_config_write(vdev, pos, count, perm, offset, val); + if (count < 0) + return count; + + if (offset == PCI_PM_CTRL) { + pci_power_t state; + + switch (le32_to_cpu(val) & PCI_PM_CTRL_STATE_MASK) { + case 0: + state = PCI_D0; + break; + case 1: + state = PCI_D1; + break; + case 2: + state = PCI_D2; + break; + case 3: + state = PCI_D3hot; + break; + } + + pci_set_power_state(vdev->pdev, state); + } + + return count; +} + /* Permissions for the Power Management capability */ static int __init init_pci_cap_pm_perm(struct perm_bits *perm) { if (alloc_perm_bits(perm, pci_cap_length[PCI_CAP_ID_PM])) return -ENOMEM; + perm->writefn = vfio_pm_config_write; + /* * We always virtualize the next field so we can remove * capabilities from the chain if we want to. @@ -600,10 +634,11 @@ static int __init init_pci_cap_pm_perm(struct perm_bits *perm) p_setb(perm, PCI_CAP_LIST_NEXT, (u8)ALL_VIRT, NO_WRITE); /* - * Power management is defined *per function*, - * so we let the user write this + * Power management is defined *per function*, so we can let + * the user change power state, but we trap and initiate the + * change ourselves, so the state bits are read-only. */ - p_setd(perm, PCI_PM_CTRL, NO_VIRT, ALL_WRITE); + p_setd(perm, PCI_PM_CTRL, NO_VIRT, ~PCI_PM_CTRL_STATE_MASK); return 0; } |
