pcie: introduce pcie_sltctl_powered_off() helper

In pcie_cap_slot_write_config() we check for PCI_EXP_SLTCTL_PWR_OFF in
a bad form. We should distinguish PCI_EXP_SLTCTL_PWR which is a "mask"
and PCI_EXP_SLTCTL_PWR_OFF which is value for that mask.

Better code is in pcie_cap_slot_unplug_request_cb() and in
pcie_cap_update_power(). Let's use same pattern everywhere. To simplify
things add also a helper.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Anton Kuchin <antonkuchin@yandex-team.ru>
Message-Id: <20230216180356.156832-12-vsementsov@yandex-team.ru>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Vladimir Sementsov-Ogievskiy 2023-02-16 21:03:49 +03:00 committed by Michael S. Tsirkin
parent f90d932094
commit 5aaed9caf1

View File

@ -39,6 +39,11 @@
#define PCIE_DEV_PRINTF(dev, fmt, ...) \
PCIE_DPRINTF("%s:%x "fmt, (dev)->name, (dev)->devfn, ## __VA_ARGS__)
static bool pcie_sltctl_powered_off(uint16_t sltctl)
{
return (sltctl & PCI_EXP_SLTCTL_PCC) == PCI_EXP_SLTCTL_PWR_OFF
&& (sltctl & PCI_EXP_SLTCTL_PIC) == PCI_EXP_SLTCTL_PWR_IND_OFF;
}
/***************************************************************************
* pci express capability helper functions
@ -395,6 +400,7 @@ static void pcie_cap_update_power(PCIDevice *hotplug_dev)
if (sltcap & PCI_EXP_SLTCAP_PCP) {
power = (sltctl & PCI_EXP_SLTCTL_PCC) == PCI_EXP_SLTCTL_PWR_ON;
/* Don't we need to check also (sltctl & PCI_EXP_SLTCTL_PIC) ? */
}
pci_for_each_device(sec_bus, pci_bus_num(sec_bus),
@ -579,8 +585,7 @@ void pcie_cap_slot_unplug_request_cb(HotplugHandler *hotplug_dev,
return;
}
if (((sltctl & PCI_EXP_SLTCTL_PIC) == PCI_EXP_SLTCTL_PWR_IND_OFF) &&
((sltctl & PCI_EXP_SLTCTL_PCC) == PCI_EXP_SLTCTL_PWR_OFF)) {
if (pcie_sltctl_powered_off(sltctl)) {
/* slot is powered off -> unplug without round-trip to the guest */
pcie_cap_slot_do_unplug(hotplug_pdev);
hotplug_event_notify(hotplug_pdev);
@ -770,10 +775,9 @@ void pcie_cap_slot_write_config(PCIDevice *dev,
* this is a work around for guests that overwrite
* control of powered off slots before powering them on.
*/
if ((sltsta & PCI_EXP_SLTSTA_PDS) && (val & PCI_EXP_SLTCTL_PCC) &&
(val & PCI_EXP_SLTCTL_PIC) == PCI_EXP_SLTCTL_PWR_IND_OFF &&
(!(old_slt_ctl & PCI_EXP_SLTCTL_PCC) ||
(old_slt_ctl & PCI_EXP_SLTCTL_PIC) != PCI_EXP_SLTCTL_PWR_IND_OFF)) {
if ((sltsta & PCI_EXP_SLTSTA_PDS) && pcie_sltctl_powered_off(val) &&
!pcie_sltctl_powered_off(old_slt_ctl))
{
pcie_cap_slot_do_unplug(dev);
}
pcie_cap_update_power(dev);