diff options
| -rw-r--r-- | drivers/vfio/pci/vfio_pci.c | 36 |
1 files changed, 33 insertions, 3 deletions
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index d0f1e70..049b9e9 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -50,6 +50,11 @@ module_param(disable_vga, bool, S_IRUGO); MODULE_PARM_DESC(disable_vga, "Disable VGA resource access through vfio-pci"); #endif +static bool disable_idle_d3; +module_param(disable_idle_d3, bool, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(disable_idle_d3, + "Disable using the PCI D3 low power state for idle, unused devices"); + static DEFINE_MUTEX(driver_lock); static inline bool vfio_vga_disabled(void) @@ -114,6 +119,8 @@ static int vfio_pci_enable(struct vfio_pci_device *vdev) u16 cmd; u8 msix_pos; + pci_set_power_state(pdev, PCI_D0); + /* Don't allow our initial saved state to include busmaster */ pci_clear_master(pdev); @@ -225,6 +232,9 @@ out: pci_disable_device(pdev); vfio_pci_try_bus_reset(vdev); + + if (!disable_idle_d3) + pci_set_power_state(pdev, PCI_D3hot); } static void vfio_pci_release(void *device_data) @@ -951,6 +961,20 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) vfio_pci_set_vga_decode(vdev, false)); } + if (!disable_idle_d3) { + /* + * pci-core sets the device power state to an unknown value at + * bootup and after being removed from a driver. The only + * transition it allows from this unknown state is to D0, which + * typically happens when a driver calls pci_enable_device(). + * We're not ready to enable the device yet, but we do want to + * be able to get to D3. Therefore first do a D0 transition + * before going to D3. + */ + pci_set_power_state(pdev, PCI_D0); + pci_set_power_state(pdev, PCI_D3hot); + } + return ret; } @@ -971,6 +995,9 @@ static void vfio_pci_remove(struct pci_dev *pdev) VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM | VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM); } + + if (!disable_idle_d3) + pci_set_power_state(pdev, PCI_D0); } static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev, @@ -1089,10 +1116,13 @@ static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev) put_devs: for (i = 0; i < devs.cur_index; i++) { - if (!ret) { - tmp = vfio_device_data(devs.devices[i]); + tmp = vfio_device_data(devs.devices[i]); + if (!ret) tmp->needs_reset = false; - } + + if (!tmp->refcnt && !disable_idle_d3) + pci_set_power_state(tmp->pdev, PCI_D3hot); + vfio_device_put(devs.devices[i]); } |