Sync with BSuSP

code/ap_boot_copy.cpp

@@ -4,8 +4,8 @@ void *startupCodeMemory = memoryService.mapIO(0x8000, Util::PAGESIZE);
 
 // Identity map the allocated physical memory to the kernel address space
 memoryService.unmap(reinterpret_cast<uint32_t>(startupCodeMemory));
-memoryService.mapPhysicalAddress(0x8000, 0x8000,
-                                 Kernel::Paging::PRESENT | Kernel::Paging::READ_WRITE);
+memoryService.mapPhysicalAddress(0x8000, 0x8000, Kernel::Paging::PRESENT
+                                               | Kernel::Paging::READ_WRITE);
 
 // Copy the startup routine and prepared variables to the identity mapped page
 auto startupCode = Util::Address<uint32_t>(reinterpret_cast<uint32_t>(&boot_ap));

code/ap_boot_protected_ap.asm

@@ -6,18 +6,18 @@
     mov edi, ebx ; Now the ID is in EDI
 
     ; Load the AP's prepared GDT and TSS
-    mov ebx, [boot_ap_gdts - boot_ap + startup_address]
-    mov eax, [ebx + edi * 0x4]
+    mov ebx, [boot_ap_gdts - boot_ap + 0x8000]
+    mov eax, [ebx + edi * 0x4] ; Select the GDT
     lgdt [eax]
     mov ax, 0x28
     ltr ax
 
     ; Load the correct stack for this AP
-    mov ebx, [boot_ap_stacks - boot_ap + startup_address]
-    mov esp, [ebx + edi * 0x4]
-    add esp, stack_size ; Stack starts at the bottom
+    mov ebx, [boot_ap_stacks - boot_ap + 0x8000]
+    mov esp, [ebx + edi * 0x4] ; Select the stack
+    add esp, 0x1000 ; Stack starts at the bottom
     mov ebp, esp
 
-    ; Call the entry function
+    ; Call the entry function smpEntry(uint8_t cpuid)
     push edi
-    call [boot_ap_entry - boot_ap + startup_address]
+    call [boot_ap_entry - boot_ap + 0x8000]

code/ap_boot_protected_bsp.asm

@@ -1,12 +1,13 @@
 ; This section has to be compiled for 32-bit protected mode
+bits 32
 boot_ap_32:
     ; Set cr3, cr0 and cr4 to the BSP's values for paging
-    mov eax, [boot_ap_cr3 - boot_ap + startup_address]
+    mov eax, [boot_ap_cr3 - boot_ap + 0x8000]
     mov cr3, eax
-    mov eax, [boot_ap_cr0 - boot_ap + startup_address]
+    mov eax, [boot_ap_cr0 - boot_ap + 0x8000]
     mov cr0, eax
-    mov eax, [boot_ap_cr4 - boot_ap + startup_address]
+    mov eax, [boot_ap_cr4 - boot_ap + 0x8000]
     mov cr4, eax
 
     ; Load the system IDT
-    lidt [boot_ap_idtr - boot_ap + startup_address]
+    lidt [boot_ap_idtr - boot_ap + 0x8000]

code/ap_boot_real_prepare.asm

@@ -1,4 +1,6 @@
 ; This section has to be compiled for 16-bit real mode
+[SECTION .text]
+bits 16
 boot_ap:
     ; Disable interrupts
     cli

code/ap_boot_variables.asm

@@ -0,0 +1,43 @@
+; Export the variables to allow initialization by C++ code
+global boot_ap_idtr
+global boot_ap_cr0
+global boot_ap_cr3
+global boot_ap_cr4
+global boot_ap_gdts
+global boot_ap_stacks
+global boot_ap_entry
+
+[SECTION .text]
+align 8
+bits 16
+boot_ap:
+; [...] boot_ap 16-bit
+
+; The variables initialized during runtime
+align 8
+boot_ap_idtr:
+    dw 0x0
+    dd 0x0
+align 8
+boot_ap_cr0:
+    dd 0x0
+align 8
+boot_ap_cr3:
+    dd 0x0
+align 8
+boot_ap_cr4:
+    dd 0x0
+align 8
+boot_ap_gdts:
+    dd 0x0
+align 8
+boot_ap_stacks:
+    dd 0x0
+align 8
+boot_ap_entry:
+    dd 0x0
+
+bits 32
+align 8
+boot_ap_32:
+; [...] boot_ap_32 32-bit

code/apictimer_trigger.cpp

@@ -13,7 +13,7 @@ void ApicTimer::trigger(const InterruptFrame &frame) {
         return;
     }
 
-    // Trigger preemption
+    // BSP triggers preemption
     if (time.toMilliseconds() % yieldInterval == 0) {
         System::getService<SchedulerService>().yield();
     }

code/ioapic_redtbl_example.cpp

@@ -2,7 +2,6 @@
 void IoApic::initializeREDTBL() {
     // GSI2 belongs to the PIT in many systems
     auto gsi = GlobalSystemInterrupt(2);
-    IrqOverride *override = getOverride(gsi);
 
     REDTBLEntry redtblEntry{};
     redtblEntry.deliveryMode    = REDTBLEntry::DeliveryMode::FIXED;
@@ -10,6 +9,7 @@ void IoApic::initializeREDTBL() {
     redtblEntry.isMasked        = true;
     redtblEntry.destination     = LocalApic::getId(); // Redirect to BSP
 
+    IrqOverride *override = getOverride(gsi);
     if (override != nullptr) {
         // Apply any information provided by an interrupt override
         redtblEntry.vector      = override->source + 32;

code/lapic_lvt_example.cpp

@@ -1,7 +1,10 @@
-LVTEntry lvtEntry{};
-lvtEntry.deliveryMode = LVTEntry::DeliveryMode::FIXED;
-lvtEntry.pinPolarity  = LVTEntry::PinPolarity::HIGH;
-lvtEntry.triggerMode  = LVTEntry::TriggerMode::EDGE;
-lvtEntry.isMasked     = true;
-lvtEntry.vector       = InterruptVector::LINT0;
-writeLVT(LINT0, lvtEntry);
+// Excerpt from the initializeLVT function
+void LocalApic::initializeLVT() {
+    LVTEntry lvtEntry{};
+    lvtEntry.deliveryMode = LVTEntry::DeliveryMode::FIXED;
+    lvtEntry.pinPolarity  = LVTEntry::PinPolarity::HIGH;
+    lvtEntry.triggerMode  = LVTEntry::TriggerMode::EDGE;
+    lvtEntry.isMasked     = true;
+    lvtEntry.vector       = InterruptVector::ERROR;
+    writeLVT(ERROR, lvtEntry);
+}

code/lapic_svr_example.cpp

@@ -1,4 +1,7 @@
-SVREntry svrEntry{};
-svrEntry.vector      = InterruptVector::SPURIOUS;
-svrEntry.isSWEnabled = true; // Keep the APIC software enabled
-writeSVR(svrEntry);
+// Excerpt from the initialize function
+void LocalApic::initialize() {
+    SVREntry svrEntry{};
+    svrEntry.vector      = InterruptVector::SPURIOUS;
+    svrEntry.isSWEnabled = true; // Keep the APIC software enabled
+    writeSVR(svrEntry);
+}

code/pit_early_delay.cpp

@@ -2,7 +2,7 @@
 void Pit::earlyDelay(uint16_t us) {
     uint32_t counter = (static_cast<double>(BASE_FREQUENCY) / 1'000'000) * us;
 
-    controlPort.writeByte(0b110000);                                  // Channel 0, mode 0
+    controlPort.writeByte(0b110000); // Channel 0, mode 0
     dataPort0.writeByte(static_cast<uint8_t>(counter & 0xFF));        // Low byte
     dataPort0.writeByte(static_cast<uint8_t>((counter >> 8) & 0xFF)); // High byte