Files
ladybird/Kernel/Prekernel/Arch/aarch64/init.cpp
Marcin Undak 18eb4a59d6 Kernel: Print current CPU exception level after booting on Aarch64
This is a first step to switch to exception level 1.

This is also my first patch for SerenityOS :)
2021-10-15 17:47:39 +01:00

69 lines
1.8 KiB
C++

/*
* Copyright (c) 2021, Nico Weber <thakis@chromium.org>
* Copyright (c) 2021, Marcin Undak <mcinek@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Types.h>
#include <Kernel/Prekernel/Arch/aarch64/Aarch64_asm_utils.h>
#include <Kernel/Prekernel/Arch/aarch64/Mailbox.h>
#include <Kernel/Prekernel/Arch/aarch64/Timer.h>
#include <Kernel/Prekernel/Arch/aarch64/UART.h>
extern "C" [[noreturn]] void halt();
extern "C" [[noreturn]] void init();
extern "C" [[noreturn]] void init()
{
auto& uart = Prekernel::UART::the();
uart.print_str("\r\nWelcome to Serenity OS!\r\n");
uart.print_str("Imagine this being your ideal operating system.\r\n");
uart.print_str("Observed deviations from that ideal are shortcomings of your imagination.\r\n\r\n");
u32 firmware_version = Prekernel::Mailbox::query_firmware_version();
uart.print_str("Firmware version: ");
uart.print_num(firmware_version);
uart.print_str("\r\n");
auto exception_level = get_current_exception_level();
uart.print_str("Current CPU exception level: EL");
uart.print_num(exception_level);
uart.print_str("\r\n");
auto& timer = Prekernel::Timer::the();
u64 start_musec = 0;
for (;;) {
u64 now_musec;
while ((now_musec = timer.microseconds_since_boot()) - start_musec < 1'000'000)
;
start_musec = now_musec;
uart.print_str("Timer: ");
uart.print_num(now_musec);
uart.print_str("\r\n");
}
}
// FIXME: Share this with the Intel Prekernel.
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();
}
[[noreturn]] void __assertion_failed(char const*, char const*, unsigned int, char const*)
{
halt();
}