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map apic

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This commit is contained in:
Eggert Jung
2026-02-03 18:13:22 +01:00
parent 609a8e80ef
commit 8cab43f197
3 changed files with 72 additions and 26 deletions
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2
kernel/main.cc
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@@ -45,7 +45,7 @@ static KeyboardApplication kapp;
// Main function // Main function
extern "C" int main() { extern "C" int main() {
//PageFrameAllocator::init(); PageFrameAllocator::init();
memset(&paging_tree, 0, sizeof(four_lvl_paging_t)); memset(&paging_tree, 0, sizeof(four_lvl_paging_t));
create_basic_page_table((uintptr_t)&paging_tree); create_basic_page_table((uintptr_t)&paging_tree);
load_cr3((void*)&paging_tree.l4); load_cr3((void*)&paging_tree.l4);

61
kernel/memory/pagetable.cc
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@@ -11,22 +11,22 @@ void create_basic_page_table(uintptr_t base){
//pagetable_entry_t *l1 = (pagetable_entry_t *) (base + (7 * 4096)); //pagetable_entry_t *l1 = (pagetable_entry_t *) (base + (7 * 4096));
four_lvl_paging_t* table = (four_lvl_paging_t*)base; four_lvl_paging_t* table = (four_lvl_paging_t*)base;
table->l4 = { table->l4.entries[0] = {
.present = 0, .present = 1,
.write = 0, .write = 1,
.user = 0, .user = 1,
.address = 0, //(uintptr_t)&(table->l3) >> 12, .address = (uintptr_t)&(table->l3) >> 12,
}; };
table->l3 = { table->l3.entries[0] = {
.present = 1, .present = 1,
.write = 1, .write = 1,
.user = 1, .user = 1,
.address = (uintptr_t)&(table->l2) >> 12, .address = (uintptr_t)&(table->l2) >> 12,
}; };
for(uint32_t i=0; i<sizeof(table->l2)/sizeof(table->l2[0]); i++){ for(uint32_t i=0; i<sizeof(table->l1)/sizeof(table->l1[0]); i++){
table->l2[i] = { table->l2.entries[i] = {
.present = 1, .present = 1,
.write = 1, .write = 1,
.user = 1, .user = 1,
@@ -35,7 +35,7 @@ void create_basic_page_table(uintptr_t base){
} }
//kernel memory //kernel memory
for(uintptr_t i=0; i<0x40000000/4096; i++){ for(uintptr_t i=0; i<0x4000000/4096; i++){
table->l1[i/512].entries[i%512] = { table->l1[i/512].entries[i%512] = {
.present = 1, .present = 1,
.write = 1, .write = 1,
@@ -44,4 +44,47 @@ void create_basic_page_table(uintptr_t base){
}; };
} }
//add ioapic address to pagetable
table->l3.entries[3] = {
.present = 1,
.write = 1,
.user = 1,
.address = (uintptr_t)&(table->l2_apic) >> 12,
};
table->l2_apic.entries[502] = {
.present = 1,
.write = 1,
.user = 1,
.address = (uintptr_t)&(table->ioapic) >> 12,
};
table->ioapic.entries[0] = {
.present = 1,
.write = 1,
.user = 0,
.address = 0xFEC00,
};
//lapic
table->l2_apic.entries[503] = {
.present = 1,
.write = 1,
.user = 1,
.address = (uintptr_t)&(table->lapic) >> 12,
};
table->lapic.entries[0] = {
.present = 1,
.write = 1,
.user = 0,
.address = 0xFEE00,
};
//unmap 0 page
table->l1[0].entries[0].present = 0;
////map ioapic
//uintptr_t ioapic_page = 0xfec00000 >> 12;
//table->l1[ioapic_page/512].entries[ioapic_page%512].address = ioapic_page;
//table->l1[ioapic_page/512].entries[ioapic_page%512].present = 1;
//table->l1[ioapic_page/512].entries[ioapic_page%512].write = 1;
} }

35
kernel/memory/pagetable.h
View File

@@ -22,24 +22,27 @@ typedef struct {
pagetable_entry_t entries[512]; pagetable_entry_t entries[512];
} pagetable_t; } pagetable_t;
typedef struct { //typedef struct {
uint8_t present:1 = 0; // uint8_t present:1 = 0;
uint8_t write:1 = 0; // uint8_t write:1 = 0;
uint8_t user:1 = 0; // uint8_t user:1 = 0;
uint8_t pwt:1 = 0; // uint8_t pwt:1 = 0;
uint8_t cache_disable:1 = 0; // uint8_t cache_disable:1 = 0;
uint8_t accessed:1 = 0; // uint8_t accessed:1 = 0;
uint8_t rsvd_0:6 = 0; // uint8_t rsvd_0:6 = 0;
uint64_t address:39 = 0; // uint64_t address:39 = 0;
uint16_t rsvd_1:10 = 0; // uint16_t rsvd_1:10 = 0;
uint8_t execute_disable:1 = 0; // uint8_t execute_disable:1 = 0;
} __attribute__((__packed__)) pagedirectory_entry_t; //} __attribute__((__packed__)) pagedirectory_entry_t;
typedef struct { typedef struct {
alignas(4096) pagedirectory_entry_t l4; alignas(4096) pagetable_t l4;
alignas(4096) pagedirectory_entry_t l3; alignas(4096) pagetable_t l3;
alignas(4096) pagedirectory_entry_t l2[32]; alignas(4096) pagetable_t l2;
alignas(4096) pagetable_t l1[32]; alignas(4096) pagetable_t l1[64];
alignas(4096) pagetable_t l2_apic;
alignas(4096) pagetable_t ioapic;
alignas(4096) pagetable_t lapic;
} four_lvl_paging_t; } four_lvl_paging_t;
void create_basic_page_table(uintptr_t base); void create_basic_page_table(uintptr_t base);