Kernel/aarch64: Add support for the Pi 5 xHCs in the RP1

This driver doesn't get the base addresses and interrupt numbers from
the devicetree, since the devicetree seems to expect that the RP1 BAR1
is set to 0. Our BAR allocator chooses a different address.

Author: spholz

Kernel/Arch/aarch64/RPi/RP1.cpp

@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2025, Sönke Holz <[email protected]>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <Kernel/Arch/aarch64/RPi/RP1.h>
+#include <Kernel/Bus/PCI/BarMapping.h>
+#include <Kernel/Bus/USB/USBManagement.h>
+#include <Kernel/Bus/USB/xHCI/xHCIController.h>
+#include <Kernel/Interrupts/IRQHandler.h>
+
+namespace Kernel::RPi {
+
+class RP1xHCIController final : public USB::xHCIController {
+public:
+    static ErrorOr<NonnullLockRefPtr<RP1xHCIController>> try_to_initialize(PhysicalAddress, size_t index, size_t interrupt_number);
+
+private:
+    RP1xHCIController(Memory::TypedMapping<u8> registers_mapping, size_t index, size_t interrupt_number);
+
+    // ^xHCIController
+    virtual bool using_message_signalled_interrupts() const override { return m_using_message_signalled_interrupts; }
+    virtual ErrorOr<OwnPtr<GenericInterruptHandler>> create_interrupter(u16 interrupter_id) override;
+    virtual ErrorOr<void> write_dmesgln_prefix(StringBuilder& builder) const override
+    {
+        TRY(builder.try_appendff("xHCI: RP1 USBHOST{}: "sv, m_index));
+        return {};
+    }
+
+    size_t m_index { 0 };
+    size_t m_interrupt_number { 0 };
+    bool m_using_message_signalled_interrupts { false };
+};
+
+ErrorOr<NonnullLockRefPtr<RP1xHCIController>> RP1xHCIController::try_to_initialize(PhysicalAddress paddr, size_t index, size_t interrupt_number)
+{
+    auto registers_mapping = TRY(Memory::map_typed_writable<u8>(paddr));
+
+    auto controller = TRY(adopt_nonnull_lock_ref_or_enomem(new (nothrow) RP1xHCIController(move(registers_mapping), index, interrupt_number)));
+    TRY(controller->initialize());
+    return controller;
+}
+
+UNMAP_AFTER_INIT RP1xHCIController::RP1xHCIController(Memory::TypedMapping<u8> registers_mapping, size_t index, size_t interrupt_number)
+    : xHCIController(move(registers_mapping))
+    , m_index(index)
+    , m_interrupt_number(interrupt_number)
+{
+}
+
+ErrorOr<OwnPtr<GenericInterruptHandler>> RP1xHCIController::create_interrupter(u16)
+{
+    // FIXME: Add interrupt support. This requires adding support for the BCM2712 MSI-X interrupt controller.
+    return nullptr;
+}
+
+ErrorOr<void> RP1::try_to_initialize_xhci_controllers(PCI::DeviceIdentifier const& pci_identifier)
+{
+    PCI::enable_memory_space(pci_identifier);
+    PCI::enable_bus_mastering(pci_identifier);
+
+    auto bar1_address = TRY(get_bar_address(pci_identifier, PCI::HeaderType0BaseRegister::BAR1));
+
+    // Chapter 5. USB, https://datasheets.raspberrypi.com/rp1/rp1-peripherals.pdf
+    // The interrupt numbers are taken from the devicetree.
+    auto usbhost0 = TRY(RP1xHCIController::try_to_initialize(bar1_address.offset(0x20'0000), 0, 31));
+    auto usbhost1 = TRY(RP1xHCIController::try_to_initialize(bar1_address.offset(0x30'0000), 1, 36));
+
+    USB::USBManagement::the().add_controller(usbhost0);
+    USB::USBManagement::the().add_controller(usbhost1);
+
+    return {};
+}
+
+}

Kernel/Arch/aarch64/RPi/RP1.h

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2025, Sönke Holz <[email protected]>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Forward.h>
+#include <Kernel/Bus/PCI/Definitions.h>
+
+namespace Kernel::RPi {
+
+class RP1 {
+public:
+    static ErrorOr<void> try_to_initialize_xhci_controllers(PCI::DeviceIdentifier const&);
+};
+
+}

Kernel/Bus/PCI/IDs.h

@@ -18,6 +18,7 @@ enum VendorID {
     VirtualBox = 0x80ee,
     VMWare = 0x15ad,
     Tdfx = 0x121a,
+    RaspberryPi = 0x1de4,
 };
 
 enum DeviceID {
@@ -27,6 +28,8 @@ enum DeviceID {
     VirtIOEntropy = 0x1005,
     VirtIOGPU = 0x1050,
     VirtIOInput = 0x1052,
+
+    RaspberryPiRP1 = 0x0001,
 };
 
 }

Kernel/Bus/USB/USBManagement.cpp

@@ -11,6 +11,7 @@
 #include <Kernel/Bus/PCI/API.h>
 #include <Kernel/Bus/PCI/Access.h>
 #include <Kernel/Bus/PCI/Definitions.h>
+#include <Kernel/Bus/PCI/IDs.h>
 #include <Kernel/Bus/USB/EHCI/EHCIController.h>
 #include <Kernel/Bus/USB/UHCI/UHCIController.h>
 #include <Kernel/Bus/USB/USBManagement.h>
@@ -19,6 +20,10 @@
 #include <Kernel/Firmware/DeviceTree/DeviceTree.h>
 #include <Kernel/Sections.h>
 
+#if ARCH(AARCH64)
+#    include <Kernel/Arch/aarch64/RPi/RP1.h>
+#endif
+
 namespace Kernel::USB {
 
 static NeverDestroyed<Vector<NonnullLockRefPtr<Driver>>> s_available_drivers;
@@ -48,6 +53,14 @@ UNMAP_AFTER_INIT void USBManagement::enumerate_controllers()
         return;
 
     MUST(PCI::enumerate([this](PCI::DeviceIdentifier const& device_identifier) {
+#if ARCH(AARCH64)
+        if (device_identifier.hardware_id().vendor_id == PCI::VendorID::RaspberryPi && device_identifier.hardware_id().device_id == PCI::DeviceID::RaspberryPiRP1) {
+            if (auto result = RPi::RP1::try_to_initialize_xhci_controllers(device_identifier); result.is_error()) {
+                dmesgln("USBManagement: Failed to initialize RP1 xHCI controllers: {}", result.release_error());
+            }
+        }
+#endif
+
         if (device_identifier.class_code() != PCI::ClassID::SerialBus
             || device_identifier.subclass_code() != PCI::SerialBus::SubclassID::USB)
             return;
@@ -131,6 +144,11 @@ USBManagement& USBManagement::the()
     return *s_the;
 }
 
+void USBManagement::add_controller(NonnullLockRefPtr<USBController> controller)
+{
+    m_controllers.append(controller);
+}
+
 void USBManagement::add_recipe(DeviceTree::DeviceRecipe<NonnullLockRefPtr<USBController>> recipe)
 {
     s_recipes->append(move(recipe));

Kernel/Bus/USB/USBManagement.h

@@ -25,6 +25,8 @@ class USBManagement {
     static LockRefPtr<Driver> get_driver_by_name(StringView name);
     static void unregister_driver(NonnullLockRefPtr<Driver> driver);
 
+    void add_controller(NonnullLockRefPtr<USBController>);
+
     static void add_recipe(DeviceTree::DeviceRecipe<NonnullLockRefPtr<USBController>>);
 
     static Vector<NonnullLockRefPtr<Driver>>& available_drivers();

Kernel/CMakeLists.txt

@@ -482,6 +482,7 @@ elseif("${SERENITY_ARCH}" STREQUAL "aarch64")
         Arch/aarch64/RPi/InterruptController.cpp
         Arch/aarch64/RPi/Mailbox.cpp
         Arch/aarch64/RPi/MiniUART.cpp
+        Arch/aarch64/RPi/RP1.cpp
         Arch/aarch64/RPi/SDHostController.cpp
         Arch/aarch64/RPi/Timer.cpp
         Arch/aarch64/RPi/Watchdog.cpp