diff options
Diffstat (limited to 'arch/x86_64/src/context_switching/main.cpp')
| -rw-r--r-- | arch/x86_64/src/context_switching/main.cpp | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/arch/x86_64/src/context_switching/main.cpp b/arch/x86_64/src/context_switching/main.cpp index 5d19f23..a5bd3fb 100644 --- a/arch/x86_64/src/context_switching/main.cpp +++ b/arch/x86_64/src/context_switching/main.cpp @@ -13,22 +13,21 @@ namespace teachos::arch::context_switching decltype(auto) global_descriptor_table = segment_descriptor_table::initialize_global_descriptor_table(); decltype(auto) interrupt_descriptor_table = interrupt_descriptor_table::initialize_interrupt_descriptor_table(); - interrupt_descriptor_table::segment_selector segment_selector{ - 1U, interrupt_descriptor_table::segment_selector::REQUEST_LEVEL_KERNEL}; - kernel::cpu::far_pointer pointer{boot::reload_segment_register, segment_selector}; - kernel::cpu::jmp(pointer); + kernel::cpu::far_pointer pointer{&boot::reload_segment_register, 1 * sizeof(segment_descriptor_table::segment_descriptor)}; + asm volatile("rex64 lcall *%[far_function_pointer]" : : [far_function_pointer] "m" (pointer)); - // Load task state segment descriptor from the last element in the global descriptor table, done by calculating - // offset in bytes to the start of the segment descriptor (5 * 16) = 80 - uint16_t const tss_selector = - (global_descriptor_table.size() - 1) * sizeof(segment_descriptor_table::segment_descriptor); - kernel::cpu::load_task_register(tss_selector); + // // Load task state segment descriptor from the last element in the global descriptor table, done by calculating + // // offset in bytes to the start of the segment descriptor (5 * 16) = 80 + // uint16_t const tss_selector = + // (global_descriptor_table.size() - 1) * sizeof(segment_descriptor_table::segment_descriptor); + // kernel::cpu::load_task_register(tss_selector); - auto const stored_task_register = kernel::cpu::store_task_register(); - arch::exception_handling::assert(tss_selector == stored_task_register, - "[Global Descriptor Table] Loaded TR value is not the same as the stored value."); + // auto const stored_task_register = kernel::cpu::store_task_register(); + // arch::exception_handling::assert(tss_selector == stored_task_register, + // "[Global Descriptor Table] Loaded TR value is not the same as the stored value."); - kernel::cpu::set_interrupt_flag(); + // FIXME: We currently cannot enable interrupts, since for some reason, we will later run into what looks like a GP. Maybe because no IDT is loaded? Maybe our boot code segment is not set up correctly? + // kernel::cpu::set_interrupt_flag(); descriptor_tables tables = {global_descriptor_table, interrupt_descriptor_table}; return tables; |