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| author | Boqun Feng <boqun.feng@gmail.com> | 2021-07-27 02:06:50 +0800 |
|---|---|---|
| committer | Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> | 2021-08-23 10:59:26 +0100 |
| commit | 15d82ca23c996d50062286d27ed6a42a8105c04a (patch) | |
| tree | 9cd2e429798627d35f07c193be7ee87c01dc7d6f /drivers/pci/probe.c | |
| parent | e73f0f0ee7541171d89f2e2491130c7771ba58d3 (diff) | |
| download | linux-15d82ca23c996d50062286d27ed6a42a8105c04a.tar.gz | |
PCI: Introduce domain_nr in pci_host_bridge
Currently we retrieve the PCI domain number of the host bridge from the
bus sysdata (or pci_config_window if PCI_DOMAINS_GENERIC=y). Actually
we have the information at PCI host bridge probing time, and it makes
sense that we store it into pci_host_bridge. One benefit of doing so is
the requirement for supporting PCI on Hyper-V for ARM64, because the
host bridge of Hyper-V doesn't have pci_config_window, whereas ARM64 is
a PCI_DOMAINS_GENERIC=y arch, so we cannot retrieve the PCI domain
number from pci_config_window on ARM64 Hyper-V guest.
As the preparation for ARM64 Hyper-V PCI support, we introduce the
domain_nr in pci_host_bridge and a sentinel value to allow drivers to
set domain numbers properly at probing time. Currently
CONFIG_PCI_DOMAINS_GENERIC=y archs are only users of this
newly-introduced field.
Link: https://lore.kernel.org/r/20210726180657.142727-2-boqun.feng@gmail.com
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci/probe.c')
| -rw-r--r-- | drivers/pci/probe.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 79177ac37880f..60c50d4f156fa 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -594,6 +594,7 @@ static void pci_init_host_bridge(struct pci_host_bridge *bridge) bridge->native_pme = 1; bridge->native_ltr = 1; bridge->native_dpc = 1; + bridge->domain_nr = PCI_DOMAIN_NR_NOT_SET; device_initialize(&bridge->dev); } @@ -898,7 +899,10 @@ static int pci_register_host_bridge(struct pci_host_bridge *bridge) bus->ops = bridge->ops; bus->number = bus->busn_res.start = bridge->busnr; #ifdef CONFIG_PCI_DOMAINS_GENERIC - bus->domain_nr = pci_bus_find_domain_nr(bus, parent); + if (bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET) + bus->domain_nr = pci_bus_find_domain_nr(bus, parent); + else + bus->domain_nr = bridge->domain_nr; #endif b = pci_find_bus(pci_domain_nr(bus), bridge->busnr); |