Kernel: Rename Aarch64Asm -> ASM_wrapper and add Aarch64::Asm namespace

Author: https://github.com/jamesmintram
Commit: https://github.com/SerenityOS/serenity/commit/4a4a3193f84
Pull-request: https://github.com/SerenityOS/serenity/pull/10514
Reviewed-by: https://github.com/mundak ✅
Reviewed-by: https://github.com/nico

Kernel/Arch/aarch64/ASM_wrapper.h

@@ -8,7 +8,7 @@
 
 #include <Kernel/Arch/aarch64/Registers.h>
 
-namespace Kernel {
+namespace Kernel::Aarch64::Asm {
 
 inline void set_ttbr1_el1(FlatPtr ttbr1_el1)
 {

Kernel/Prekernel/Arch/aarch64/Prekernel.h

@@ -13,11 +13,6 @@ void init_prekernel_page_tables();
 
 [[noreturn]] void panic(const char* msg);
 
-[[noreturn]] inline void halt()
-{
-    for (;;) {
-        asm volatile("wfi");
-    }
-}
+[[noreturn]] void halt();
 
 }

Kernel/Prekernel/Arch/aarch64/PrekernelCommon.cpp

@@ -6,7 +6,7 @@
 
 #include <Kernel/Prekernel/Arch/aarch64/Prekernel.h>
 
-#include <Kernel/Arch/aarch64/Aarch64Asm.h>
+#include <Kernel/Arch/aarch64/ASM_wrapper.h>
 #include <Kernel/Prekernel/Arch/aarch64/UART.h>
 
 namespace Prekernel {
@@ -19,7 +19,14 @@ namespace Prekernel {
         uart.print_str(msg);
     }
 
-    Kernel::halt();
+    Prekernel::halt();
+}
+
+[[noreturn]] void halt()
+{
+    for (;;) {
+        asm volatile("wfi");
+    }
 }
 
 }

Kernel/Prekernel/Arch/aarch64/PrekernelExceptions.cpp

@@ -4,7 +4,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
-#include <Kernel/Arch/aarch64/Aarch64Asm.h>
+#include <Kernel/Arch/aarch64/ASM_wrapper.h>
 #include <Kernel/Arch/aarch64/Registers.h>
 #include <Kernel/Prekernel/Arch/aarch64/Aarch64_asm_utils.h>
 #include <Kernel/Prekernel/Arch/aarch64/Prekernel.h>
@@ -82,14 +82,14 @@ static void set_up_el1()
 
 void drop_to_exception_level_1()
 {
-    switch (Kernel::get_current_exception_level()) {
-    case ExceptionLevel::EL3:
+    switch (Kernel::Aarch64::Asm::get_current_exception_level()) {
+    case Kernel::Aarch64::Asm::ExceptionLevel::EL3:
         drop_to_el2();
         [[fallthrough]];
-    case ExceptionLevel::EL2:
+    case Kernel::Aarch64::Asm::ExceptionLevel::EL2:
         drop_to_el1();
         [[fallthrough]];
-    case ExceptionLevel::EL1:
+    case Kernel::Aarch64::Asm::ExceptionLevel::EL1:
         set_up_el1();
         break;
     default: {

Kernel/Prekernel/Arch/aarch64/PrekernelMMU.cpp

@@ -8,7 +8,7 @@
 
 #include <Kernel/Prekernel/Arch/aarch64/Prekernel.h>
 
-#include <Kernel/Arch/aarch64/Aarch64Asm.h>
+#include <Kernel/Arch/aarch64/ASM_wrapper.h>
 #include <Kernel/Arch/aarch64/Registers.h>
 #include <Kernel/Prekernel/Arch/aarch64/UART.h>
 
@@ -108,8 +108,8 @@ static void build_identity_map(page_table_t page_table)
 
 static void switch_to_page_table(u8* page_table)
 {
-    set_ttbr0_el1((FlatPtr)page_table);
-    set_ttbr1_el1((FlatPtr)page_table);
+    Aarch64::Asm::set_ttbr0_el1((FlatPtr)page_table);
+    Aarch64::Asm::set_ttbr1_el1((FlatPtr)page_table);
 }
 
 static void activate_mmu()
@@ -144,7 +144,7 @@ static void activate_mmu()
     sctlr_el1.M = 1; //Enable MMU
     Aarch64::SCTLR_EL1::write(sctlr_el1);
 
-    flush();
+    Aarch64::Asm::flush();
 }
 
 void init_prekernel_page_tables()

Kernel/Prekernel/Arch/aarch64/boot.S

@@ -13,7 +13,7 @@ start:
   // Let only core 0 continue, put other cores to sleep.
   mrs x13, MPIDR_EL1
   and x13, x13, 0xff
-  cbnz x13, halt
+  cbnz x13, _ZN9Prekernel4haltEv
 
   // Let stack start before .text for now.
   // 512 kiB (0x80000) of stack are probably not sufficient, especially once we give the other cores some stack too,

Kernel/Prekernel/Arch/aarch64/init.cpp

@@ -7,7 +7,7 @@
 
 #include <AK/Types.h>
 
-#include <Kernel/Arch/aarch64/Aarch64Asm.h>
+#include <Kernel/Arch/aarch64/ASM_wrapper.h>
 #include <Kernel/Prekernel/Arch/aarch64/Aarch64_asm_utils.h>
 #include <Kernel/Prekernel/Arch/aarch64/BootPPMParser.h>
 #include <Kernel/Prekernel/Arch/aarch64/Framebuffer.h>
@@ -20,6 +20,8 @@
 static void draw_logo();
 static u32 query_firmware_version();
 
+extern "C" void wait_cycles(int n);
+
 extern "C" [[noreturn]] void halt();
 extern "C" [[noreturn]] void init();
 
@@ -37,7 +39,7 @@ extern "C" [[noreturn]] void init()
     uart.print_str("\r\n");
 
     uart.print_str("CPU started in: EL");
-    uart.print_num(static_cast<u64>(Kernel::get_current_exception_level()));
+    uart.print_num(static_cast<u64>(Kernel::Aarch64::Asm::get_current_exception_level()));
     uart.print_str("\r\n");
 
     uart.print_str("Drop CPU to EL1\r\n");
@@ -71,21 +73,14 @@ extern size_t __stack_chk_guard;
 size_t __stack_chk_guard;
 extern "C" [[noreturn]] void __stack_chk_fail();
 
-[[noreturn]] void halt()
-{
-    for (;;) {
-        asm volatile("wfi");
-    }
-}
-
 void __stack_chk_fail()
 {
-    halt();
+    Prekernel::halt();
 }
 
 [[noreturn]] void __assertion_failed(char const*, char const*, unsigned int, char const*)
 {
-    halt();
+    Prekernel::halt();
 }
 
 class QueryFirmwareVersionMboxMessage : Prekernel::Mailbox::Message {
@@ -160,7 +155,7 @@ static void draw_logo()
                     break;
                 default:
                     Prekernel::warnln("Unsupported pixel format");
-                    halt();
+                    Prekernel::halt();
                 }
 
                 logo_pixels += 3;

Kernel/Prekernel/CMakeLists.txt

@@ -24,9 +24,6 @@ if ("${SERENITY_ARCH}" STREQUAL "aarch64")
         # Assembly
         Arch/aarch64/boot.S
         Arch/aarch64/Aarch64_asm_utils.S
-
-        # Shared with kernel
-        ../Arch/aarch64/Aarch64Asm.cpp
     )
 else()
     set(SOURCES