diff options
Diffstat (limited to 'Kernel/PCI/IOAccess.cpp')
| -rw-r--r-- | Kernel/PCI/IOAccess.cpp | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/Kernel/PCI/IOAccess.cpp b/Kernel/PCI/IOAccess.cpp index d2fc93defb..ebcc155d06 100644 --- a/Kernel/PCI/IOAccess.cpp +++ b/Kernel/PCI/IOAccess.cpp @@ -67,17 +67,26 @@ void IOAccess::write32_field(Address address, u32 field, u32 value) void IOAccess::enumerate_hardware(Function<void(Address, ID)> callback) { dbgln_if(PCI_DEBUG, "PCI: IO enumerating hardware"); - // Single PCI host controller. - if ((read8_field(Address(), PCI_HEADER_TYPE) & 0x80) == 0) { - enumerate_bus(-1, 0, callback, true); - return; - } - // Multiple PCI host controllers. - for (int bus = 0; bus < 256; ++bus) { - if (read16_field(Address(0, 0, 0, bus), PCI_VENDOR_ID) == PCI_NONE) - break; - enumerate_bus(-1, bus, callback, false); + // First scan bus 0. Find any device on that bus, and if it's a PCI-to-PCI + // bridge, recursively scan it too. + m_enumerated_buses.set(0, true); + enumerate_bus(-1, 0, callback, true); + + // Handle Multiple PCI host bridges on slot 0, device 0. + // If we happen to miss some PCI buses because they are not reachable through + // recursive PCI-to-PCI bridges starting from bus 0, we might find them here. + if ((read8_field(Address(), PCI_HEADER_TYPE) & 0x80) != 0) { + for (int bus = 1; bus < 256; ++bus) { + if (read16_field(Address(0, 0, 0, bus), PCI_VENDOR_ID) == PCI_NONE) + continue; + if (read16_field(Address(0, 0, 0, bus), PCI_CLASS) != 0x6) + continue; + if (m_enumerated_buses.get(bus)) + continue; + enumerate_bus(-1, bus, callback, false); + m_enumerated_buses.set(bus, true); + } } } |