From c035d3c82c607d2f982689951bac86b38ceab8a7 Mon Sep 17 00:00:00 2001 From: Bananymous Date: Sun, 3 Mar 2024 02:17:24 +0200 Subject: [PATCH] Kernel: Start all processors on kernel boot Processors don't do anything, except print hello message and halt. --- kernel/arch/x86_64/GDT.cpp | 2 - kernel/arch/x86_64/PageTable.cpp | 1 + kernel/arch/x86_64/boot.S | 114 +++++++++++++++++--- kernel/arch/x86_64/linker.ld | 7 ++ kernel/include/kernel/APIC.h | 2 + kernel/include/kernel/InterruptController.h | 2 + kernel/include/kernel/PIC.h | 2 + kernel/kernel/APIC.cpp | 79 ++++++++++++-- kernel/kernel/PIC.cpp | 5 + kernel/kernel/kernel.cpp | 15 ++- script/qemu.sh | 2 +- 11 files changed, 202 insertions(+), 29 deletions(-) diff --git a/kernel/arch/x86_64/GDT.cpp b/kernel/arch/x86_64/GDT.cpp index 2617ad51..1baeb334 100644 --- a/kernel/arch/x86_64/GDT.cpp +++ b/kernel/arch/x86_64/GDT.cpp @@ -3,8 +3,6 @@ #include -extern "C" uintptr_t g_boot_stack_top[0]; - namespace Kernel::GDT { diff --git a/kernel/arch/x86_64/PageTable.cpp b/kernel/arch/x86_64/PageTable.cpp index 9647c468..9d690208 100644 --- a/kernel/arch/x86_64/PageTable.cpp +++ b/kernel/arch/x86_64/PageTable.cpp @@ -306,6 +306,7 @@ namespace Kernel void PageTable::load() { + SpinLockGuard _(m_lock); asm volatile("movq %0, %%cr3" :: "r"(m_highest_paging_struct)); s_current = this; } diff --git a/kernel/arch/x86_64/boot.S b/kernel/arch/x86_64/boot.S index 331cefab..0861baca 100644 --- a/kernel/arch/x86_64/boot.S +++ b/kernel/arch/x86_64/boot.S @@ -53,12 +53,9 @@ bananboot_start: bananboot_end: .section .bss, "aw", @nobits - # Create stack - .global g_boot_stack_bottom - g_boot_stack_bottom: - .skip 16384 - .global g_boot_stack_top - g_boot_stack_top: + # reserve 4096 bytes of initial stack for each processor + g_processor_stacks: + .skip 4096 * 64 .global g_kernel_cmdline g_kernel_cmdline: @@ -105,6 +102,13 @@ boot_gdtr: .short . - boot_gdt - 1 .quad V2P(boot_gdt) +.global g_ap_startup_done +g_ap_startup_done: + .byte 0 +.global g_ap_running_count +g_ap_running_count: + .byte 0 + .section .text has_cpuid: @@ -151,6 +155,20 @@ enable_sse: movl %eax, %cr4 ret +# NOTE: return address in argument %edi +initialize_pmode_stack: + movl $1, %eax + cpuid + shrl $24, %ebx + + movw %bx, %gs + + shll $12, %ebx + addl $V2P(g_processor_stacks) + 4096, %ebx + movl %ebx, %esp + + jmp *%edi + initialize_paging: # enable PAE movl %cr4, %ecx @@ -178,10 +196,13 @@ initialize_paging: .type _start, @function _start: # Initialize stack and multiboot info - movl $V2P(g_boot_stack_top), %esp movl %eax, V2P(bootloader_magic) movl %ebx, V2P(bootloader_info) + movl $V2P(1f), %edi + jmp initialize_pmode_stack +1: + call check_requirements call enable_sse @@ -194,17 +215,15 @@ _start: .code64 long_mode: movw $0x10, %ax - movw %ax, %ss - - # clear segment registers (unused in x86_64?) - movw $0x00, %ax movw %ax, %ds + movw %ax, %ss movw %ax, %es - movw %ax, %fs - movw %ax, %gs + + # move stack pointer to higher half + movl %esp, %esp + addq $KERNEL_OFFSET, %rsp # jump to higher half - movq $g_boot_stack_top, %rsp movabsq $higher_half, %rcx jmp *%rcx @@ -227,3 +246,70 @@ system_halt: cli 1: hlt jmp 1b + + +.section .ap_init, "ax" + +.code16 +.global ap_trampoline +ap_trampoline: + cli + ljmpl $0x00, $ap_cs_clear + +ap_cs_clear: + xorw %ax, %ax + movw %ax, %ds + + # load ap gdt and enter protected mode + lgdt ap_gdtr + movl %cr0, %eax + orb $1, %al + movl %eax, %cr0 + ljmpl $0x08, $ap_protected_mode + +.code32 +ap_protected_mode: + movw $0x10, %ax + movw %ax, %ds + movw %ax, %ss + movw %ax, %es + + movl $1f, %edi + jmp V2P(initialize_pmode_stack) +1: + + # load boot gdt, load boot page table and enter long mode + call V2P(initialize_paging) + lgdt V2P(boot_gdtr) + ljmpl $0x08, $ap_long_mode + +.code64 +ap_long_mode: + # move stack pointer to higher half + movl %esp, %esp + addq $KERNEL_OFFSET, %rsp + + # jump to higher half + movabsq $ap_higher_half, %rcx + jmp *%rcx + +ap_higher_half: + # clear rbp for stacktrace + xorq %rbp, %rbp + +1: pause + cmpb $0, g_ap_startup_done + jz 1b + + lock incb g_ap_running_count + + call ap_main + jmp system_halt + +ap_gdt: + .quad 0x0000000000000000 # null descriptor + .quad 0x00CF9A000000FFFF # 32 bit code + .quad 0x00CF92000000FFFF # 32 bit data +ap_gdtr: + .short . - ap_gdt - 1 + .quad ap_gdt diff --git a/kernel/arch/x86_64/linker.ld b/kernel/arch/x86_64/linker.ld index 29e1e781..d8bb8012 100644 --- a/kernel/arch/x86_64/linker.ld +++ b/kernel/arch/x86_64/linker.ld @@ -4,6 +4,13 @@ KERNEL_OFFSET = 0xFFFFFFFF80000000; SECTIONS { + . = 0xF000; + .ap_init ALIGN(4K) : AT(ADDR(.ap_init)) + { + g_ap_init_addr = .; + *(.ap_init) + } + . = 0x00100000 + KERNEL_OFFSET; g_kernel_start = .; diff --git a/kernel/include/kernel/APIC.h b/kernel/include/kernel/APIC.h index a2e31a1d..2e57e5de 100644 --- a/kernel/include/kernel/APIC.h +++ b/kernel/include/kernel/APIC.h @@ -18,6 +18,8 @@ namespace Kernel virtual BAN::ErrorOr reserve_irq(uint8_t irq) override; virtual BAN::Optional get_free_irq() override; + virtual void initialize_multiprocessor() override; + private: uint32_t read_from_local_apic(ptrdiff_t); void write_to_local_apic(ptrdiff_t, uint32_t); diff --git a/kernel/include/kernel/InterruptController.h b/kernel/include/kernel/InterruptController.h index 7283b975..63e6bd75 100644 --- a/kernel/include/kernel/InterruptController.h +++ b/kernel/include/kernel/InterruptController.h @@ -37,6 +37,8 @@ namespace Kernel static void initialize(bool force_pic); static InterruptController& get(); + virtual void initialize_multiprocessor() = 0; + virtual BAN::ErrorOr reserve_irq(uint8_t irq) = 0; virtual BAN::Optional get_free_irq() = 0; diff --git a/kernel/include/kernel/PIC.h b/kernel/include/kernel/PIC.h index e761059a..51fe0413 100644 --- a/kernel/include/kernel/PIC.h +++ b/kernel/include/kernel/PIC.h @@ -16,6 +16,8 @@ namespace Kernel virtual BAN::ErrorOr reserve_irq(uint8_t irq) override; virtual BAN::Optional get_free_irq() override; + virtual void initialize_multiprocessor() override; + static void remap(); static void mask_all(); diff --git a/kernel/kernel/APIC.cpp b/kernel/kernel/APIC.cpp index b1b3abcb..77e22a18 100644 --- a/kernel/kernel/APIC.cpp +++ b/kernel/kernel/APIC.cpp @@ -6,20 +6,27 @@ #include #include #include +#include #include #define LAPIC_EIO_REG 0xB0 #define LAPIC_SIV_REG 0xF0 #define LAPIC_IS_REG 0x100 +#define LAPIC_ERROR_REG 0x280 +#define LAPIC_ICR_LO_REG 0x300 +#define LAPIC_ICR_HI_REG 0x310 #define IOAPIC_MAX_REDIRS 0x01 #define IOAPIC_REDIRS 0x10 -#define DEBUG_PRINT_PROCESSORS 0 - // https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#multiple-apic-description-table-madt-format +extern uint8_t g_ap_init_addr[]; + +extern volatile uint8_t g_ap_startup_done[]; +extern volatile uint8_t g_ap_running_count[]; + namespace Kernel { @@ -182,18 +189,68 @@ namespace Kernel uint32_t sivr = apic->read_from_local_apic(LAPIC_SIV_REG); apic->write_to_local_apic(LAPIC_SIV_REG, sivr | 0x1FF); - #if DEBUG_PRINT_PROCESSORS - for (auto& processor : apic->m_processors) - { - dprintln("Processor{}", processor.processor_id); - dprintln(" lapic id: {}", processor.apic_id); - dprintln(" status: {}", (processor.flags & Processor::Flags::Enabled) ? "enabled" : (processor.flags & Processor::Flags::OnlineCapable) ? "can be enabled" : "disabled"); - } - #endif - return apic; } + void APIC::initialize_multiprocessor() + { + constexpr auto udelay = + [](uint64_t us) { + uint64_t wake_time = SystemTimer::get().ns_since_boot() + us * 1000; + while (SystemTimer::get().ns_since_boot() < wake_time) + __builtin_ia32_pause(); + }; + + const auto send_ipi = + [&](uint8_t processor, uint32_t data, uint64_t ud) + { + write_to_local_apic(LAPIC_ICR_HI_REG, (read_from_local_apic(LAPIC_ICR_HI_REG) & 0x00FFFFFF) | (processor << 24)); + write_to_local_apic(LAPIC_ICR_LO_REG, data); + udelay(ud); + while (read_from_local_apic(LAPIC_ICR_LO_REG) & (1 << 12)) + __builtin_ia32_pause(); + }; + + const size_t ap_init_page = reinterpret_cast(g_ap_init_addr) / PAGE_SIZE; + + dprintln("System has {} processors", m_processors.size()); + + uint8_t bsp_id = get_processor_id(); + dprintln("BSP lapic id: {}", bsp_id); + + for (auto& processor : m_processors) + { + if (processor.apic_id == bsp_id) + continue; + + if (!(processor.flags & (Processor::Flags::Enabled | Processor::Flags::OnlineCapable))) + { + dwarnln("Skipping processor (lapic id {}) initialization", processor.apic_id); + continue; + } + + dprintln("Trying to enable processor (lapic id {})", processor.apic_id); + + write_to_local_apic(LAPIC_ERROR_REG, 0x00); + send_ipi(processor.processor_id, (read_from_local_apic(LAPIC_ICR_LO_REG) & 0xFFF00000) | 0x0000C500, 0); + send_ipi(processor.processor_id, (read_from_local_apic(LAPIC_ICR_LO_REG) & 0xFFF0F800) | 0x00008500, 0); + + udelay(10 * 1000); + + for (int i = 0; i < 2; i++) + { + write_to_local_apic(LAPIC_ERROR_REG, 0x00); + send_ipi(processor.processor_id, (read_from_local_apic(LAPIC_ICR_LO_REG) & 0xFFF0F800) | 0x00000600 | ap_init_page, 200); + } + } + + *g_ap_startup_done = 1; + + udelay(100); + + dprintln("{} processors started", *g_ap_running_count); + } + uint32_t APIC::read_from_local_apic(ptrdiff_t offset) { return MMIO::read32(m_local_apic_vaddr + offset); diff --git a/kernel/kernel/PIC.cpp b/kernel/kernel/PIC.cpp index ce106e4f..344fd98f 100644 --- a/kernel/kernel/PIC.cpp +++ b/kernel/kernel/PIC.cpp @@ -134,4 +134,9 @@ namespace Kernel return IO::inb(port) & (1 << irq); } + void PIC::initialize_multiprocessor() + { + dprintln("Only single processor supported with PIC"); + } + } diff --git a/kernel/kernel/kernel.cpp b/kernel/kernel/kernel.cpp index 11c44c65..c5bfecc2 100644 --- a/kernel/kernel/kernel.cpp +++ b/kernel/kernel/kernel.cpp @@ -19,12 +19,13 @@ #include #include #include +#include #include #include #include +#include #include #include -#include #include struct ParsedCommandLine @@ -127,6 +128,8 @@ extern "C" void kernel_main(uint32_t boot_magic, uint32_t boot_info) SystemTimer::initialize(cmdline.force_pic); dprintln("Timers initialized"); + InterruptController::get().initialize_multiprocessor(); + DevFileSystem::initialize(); dprintln("devfs initialized"); @@ -206,3 +209,13 @@ static void init2(void*) MUST(Process::create_userspace({ 0, 0, 0, 0 }, "/usr/bin/init"sv)); } + +extern "C" void ap_main() +{ + using namespace Kernel; + + dprintln("hello from processor {}", get_processor_id()); + + for (;;) + asm volatile(""); +} diff --git a/script/qemu.sh b/script/qemu.sh index 1c7fc4c7..a34c2313 100755 --- a/script/qemu.sh +++ b/script/qemu.sh @@ -21,7 +21,7 @@ fi qemu-system-$BANAN_ARCH \ -m 1G \ - -smp 2 \ + -smp 4 \ $BIOS_ARGS \ -drive format=raw,id=disk,file=${BANAN_DISK_IMAGE_PATH},if=none \ -device e1000e,netdev=net \