From 8d42b8085556abe25faa3cd35b1937707d814280 Mon Sep 17 00:00:00 2001
From: Matheus <matheusuky@gmail.com>
Date: Sun, 26 May 2024 20:51:54 -0300
Subject: [PATCH] smp: nmi ipi support

---
 kernel-src/arch/x86-64/apic.c         |  2 +-
 kernel-src/arch/x86-64/mmu.c          |  2 +-
 kernel-src/arch/x86-64/smp.c          | 19 ++++++++++++++-----
 kernel-src/include/x86-64/arch/apic.h |  2 ++
 kernel-src/include/x86-64/arch/smp.h  |  3 ++-
 5 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/kernel-src/arch/x86-64/apic.c b/kernel-src/arch/x86-64/apic.c
index ad981aee..ddffa77f 100644
--- a/kernel-src/arch/x86-64/apic.c
+++ b/kernel-src/arch/x86-64/apic.c
@@ -284,7 +284,7 @@ void arch_apic_sendipi(uint8_t cpu, uint8_t vec, uint8_t dest, uint8_t mode, uin
 	while (readlapic(APIC_REG_ICR_LO) & APIC_REG_ICR_LO_STATUS) CPU_PAUSE();
 
 	writelapic(APIC_REG_ICR_HI, (uint32_t)cpu << 24);
-	writelapic(APIC_REG_ICR_LO, vec | (level << 14) | (mode << 15) | (dest << 18));
+	writelapic(APIC_REG_ICR_LO, vec | (level << 8) | (mode << 11) | (dest << 18) | (1 << 14));
 }
 
 void arch_apic_init() {
diff --git a/kernel-src/arch/x86-64/mmu.c b/kernel-src/arch/x86-64/mmu.c
index 949a41d8..6c0f6418 100644
--- a/kernel-src/arch/x86-64/mmu.c
+++ b/kernel-src/arch/x86-64/mmu.c
@@ -220,7 +220,7 @@ void arch_mmu_tlbshootdown(void *page) {
 		mmupage = page;
 		remaining = arch_smp_cpusawake - 1;
 
-		arch_smp_sendipi(NULL, &_cpu()->isr[0xfe], ARCH_SMP_IPI_OTHERCPUS);
+		arch_smp_sendipi(NULL, &_cpu()->isr[0xfe], ARCH_SMP_IPI_OTHERCPUS, true);
 
 		while (__atomic_load_n(&remaining, __ATOMIC_SEQ_CST)) CPU_PAUSE();
 
diff --git a/kernel-src/arch/x86-64/smp.c b/kernel-src/arch/x86-64/smp.c
index 6e1acdad..ca080977 100644
--- a/kernel-src/arch/x86-64/smp.c
+++ b/kernel-src/arch/x86-64/smp.c
@@ -5,6 +5,7 @@
 #include <arch/gdt.h>
 #include <arch/idt.h>
 #include <kernel/cmdline.h>
+#include <arch/smp.h>
 
 static volatile struct limine_smp_request smprequest = {
 	.id = LIMINE_SMP_REQUEST
@@ -13,11 +14,19 @@ static volatile struct limine_smp_request smprequest = {
 // set to 1 because of the bsp
 size_t arch_smp_cpusawake = 1;
 
+// for panic. if the nosmp argument is given to the kernel, this is what the APs will jump to
+static void cpuwakeuphalt(struct limine_smp_info *info) {
+	asm("cli");
+	for (;;) CPU_HALT();
+}
+
+
 static void cpuwakeup(struct limine_smp_info *info) {
 	cpu_set((cpu_t *)info->extra_argument);
 
 	arch_gdt_reload();
 	arch_idt_reload();
+	interrupt_register(0xfd, (void *)cpuwakeuphalt, NULL, IPL_IGNORE);
 	dpc_init();
 	arch_mmu_apswitch();
 	vmm_apinit();
@@ -30,16 +39,16 @@ static void cpuwakeup(struct limine_smp_info *info) {
 	sched_apentry();
 }
 
-// if the nosmp argument is given to the kernel, this is what the APs will jump to
-static void cpuwakeuphalt(struct limine_smp_info *info) {
-	for (;;) CPU_HALT();
+void arch_smp_sendipi(cpu_t *targcpu, isr_t *isr, int target, bool nmi) {
+	arch_apic_sendipi(targcpu ? targcpu->id : 0, INTERRUPT_IDTOVECTOR(isr->id), target, nmi ? APIC_MODE_NMI : 0, 0);
 }
 
-void arch_smp_sendipi(cpu_t *targcpu, isr_t *isr, int target) {
-	arch_apic_sendipi(targcpu ? targcpu->id : 0, INTERRUPT_IDTOVECTOR(isr->id), target, 0, 1);
+void arch_smp_haltallothers() {
+	arch_smp_sendipi(NULL, &_cpu()->isr[0xfd], ARCH_SMP_IPI_OTHERCPUS, true);
 }
 
 void arch_smp_wakeup() {
+	interrupt_register(0xfd, (void *)cpuwakeuphalt, NULL, IPL_IGNORE);
 	struct limine_smp_response *response = smprequest.response;
 	if (response == NULL) {
 		// TODO try to detect the other processors manually
diff --git a/kernel-src/include/x86-64/arch/apic.h b/kernel-src/include/x86-64/arch/apic.h
index f1318b09..331042d3 100644
--- a/kernel-src/include/x86-64/arch/apic.h
+++ b/kernel-src/include/x86-64/arch/apic.h
@@ -1,6 +1,8 @@
 #ifndef _APIC_H
 #define _APIC_H
 
+#define APIC_MODE_NMI 4
+
 void arch_apic_timerinit();
 void arch_apic_init();
 void arch_apic_initap();
diff --git a/kernel-src/include/x86-64/arch/smp.h b/kernel-src/include/x86-64/arch/smp.h
index 904ba9cd..43367192 100644
--- a/kernel-src/include/x86-64/arch/smp.h
+++ b/kernel-src/include/x86-64/arch/smp.h
@@ -9,6 +9,7 @@
 extern size_t arch_smp_cpusawake;
 
 void arch_smp_wakeup();
-void arch_smp_sendipi(cpu_t *targcpu, isr_t *isr, int target);
+void arch_smp_sendipi(cpu_t *targcpu, isr_t *isr, int target, bool nmi);
+void arch_smp_haltallothers();
 
 #endif