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Ayaan Tunio
2025-02-12 09:54:05 -05:00
commit 7118adc514
1108 changed files with 80873 additions and 0 deletions
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17
boot/arm32/vmm/consts.h Normal file
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#ifndef _BOOT_VMM_CONSTS_H
#define _BOOT_VMM_CONSTS_H
#define VMM_LV0_ENTITY_COUNT (256)
#define VMM_LV1_ENTITY_COUNT (4096)
#define VMM_PAGE_SIZE (4096)
#define VMM_OFFSET_IN_DIRECTORY(a) (((a) >> 20) & 0xfff)
#define VMM_OFFSET_IN_TABLE(a) (((a) >> 12) & 0xff)
#define VMM_OFFSET_IN_PAGE(a) ((a)&0xfff)
#define TABLE_START(vaddr) ((vaddr >> 20) << 20)
#define PAGE_START(vaddr) ((vaddr >> 12) << 12)
#define FRAME(addr) (addr / VMM_PAGE_SIZE)
#define PTABLE_TOP_KERNEL_OFFSET 3072
#endif //_BOOT_VMM_CONSTS_H

147
boot/arm32/vmm/vmm.c Normal file
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#include "vmm.h"
#include <libboot/log/log.h>
#include <libboot/mem/alloc.h>
#include <libboot/mem/mem.h>
#include <libboot/types.h>
// #define DEBUG_VMM
#define VMM_OFFSET_IN_DIRECTORY(a) (((a) >> 20) & 0xfff)
#define VMM_OFFSET_IN_TABLE(a) (((a) >> 12) & 0xff)
#define VMM_OFFSET_IN_PAGE(a) ((a)&0xfff)
#define ALIGN_TO_TABLE(a) ((a)&0xfff00000)
static pdirectory_t* pdir = NULL;
static ptable_t* map_table(size_t tphyz, size_t tvirt);
static void mmu_enable();
static inline void write_ttbcr(uint32_t val)
{
asm volatile("mcr p15, 0, %0, c2, c0, 2"
:
: "r"(val)
: "memory");
asm volatile("dmb");
}
static inline void write_ttbr0(uint32_t val)
{
asm volatile("mcr p15, 0, %0, c2, c0, 0"
:
: "r"(val)
: "memory");
asm volatile("dmb");
}
static inline void write_dacr(uint32_t val)
{
asm volatile("mcr p15, 0, %0, c3, c0, 0"
:
: "r"(val));
asm volatile("dmb");
}
static void mmu_enable()
{
volatile uint32_t val;
asm volatile("mrc p15, 0, %0, c1, c0, 0"
: "=r"(val));
asm volatile("orr %0, %1, #0x1"
: "=r"(val)
: "r"(val));
asm volatile("mcr p15, 0, %0, c1, c0, 0" ::"r"(val)
: "memory");
asm volatile("isb");
}
static pdirectory_t* vm_alloc_pdir()
{
return (pdirectory_t*)malloc_aligned(sizeof(pdirectory_t), sizeof(pdirectory_t));
}
static ptable_t* vm_alloc_ptable()
{
return (ptable_t*)malloc_aligned(sizeof(ptable_t), sizeof(ptable_t));
}
static ptable_t* map_table(size_t tphyz, size_t tvirt)
{
ptable_t* table = vm_alloc_ptable();
for (size_t phyz = tphyz, virt = tvirt, i = 0; i < VMM_LV0_ENTITY_COUNT; phyz += VMM_PAGE_SIZE, virt += VMM_PAGE_SIZE, i++) {
page_desc_t new_page;
new_page.one = 1;
new_page.baddr = (phyz / VMM_PAGE_SIZE);
new_page.tex = 0b001;
new_page.c = 1;
new_page.b = 1;
new_page.ap1 = 0b11;
new_page.ap2 = 0b0;
new_page.s = 1;
table->entities[i] = new_page;
}
uint32_t table_int = (uint32_t)table;
pdir->entities[VMM_OFFSET_IN_DIRECTORY(tvirt)].valid = 1;
pdir->entities[VMM_OFFSET_IN_DIRECTORY(tvirt)].zero1 = 0;
pdir->entities[VMM_OFFSET_IN_DIRECTORY(tvirt)].zero2 = 0;
pdir->entities[VMM_OFFSET_IN_DIRECTORY(tvirt)].ns = 0;
pdir->entities[VMM_OFFSET_IN_DIRECTORY(tvirt)].zero3 = 0;
pdir->entities[VMM_OFFSET_IN_DIRECTORY(tvirt)].domain = 0b0011;
pdir->entities[VMM_OFFSET_IN_DIRECTORY(tvirt)].baddr = ((table_int / 1024));
return table;
}
static void vm_init()
{
pdir = vm_alloc_pdir();
for (int i = 0; i < VMM_LV1_ENTITY_COUNT; i++) {
pdir->entities[i].valid = 0;
}
}
static void vm_map_devices()
{
map_table(0x1c000000, 0x1c000000); // mapping uart
}
void vm_setup(size_t kernel_vaddr, size_t kernel_paddr, size_t kernel_size)
{
vm_init();
vm_map_devices();
extern int bootloader_start[];
size_t bootloader_start_aligned = ALIGN_TO_TABLE((size_t)bootloader_start);
map_table(bootloader_start_aligned, bootloader_start_aligned);
#ifdef DEBUG_VMM
log("map %x to %x", bootloader_start_aligned, bootloader_start_aligned);
#endif
size_t table_paddr = ALIGN_TO_TABLE(kernel_paddr);
size_t table_vaddr = ALIGN_TO_TABLE(kernel_vaddr);
const size_t bytes_per_table = VMM_LV0_ENTITY_COUNT * VMM_PAGE_SIZE;
const size_t tables_per_kernel = align_size((kernel_size + bytes_per_table - 1) / bytes_per_table, 4);
for (int i = 0; i < tables_per_kernel; i++) {
map_table(table_paddr, table_paddr);
map_table(table_paddr, table_vaddr);
#ifdef DEBUG_VMM
log("map %x to %x", table_paddr, table_paddr);
log("map %x to %x", table_paddr, table_vaddr);
#endif
table_paddr += bytes_per_table;
table_vaddr += bytes_per_table;
}
write_ttbr0((size_t)(pdir));
write_dacr(0x55555555);
mmu_enable();
}
void vm_setup_secondary_cpu()
{
write_ttbr0((uint32_t)(pdir));
write_dacr(0x55555555);
mmu_enable();
}

54
boot/arm32/vmm/vmm.h Normal file
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#ifndef _BOOT_VMM_VMM_H
#define _BOOT_VMM_VMM_H
#include "consts.h"
#include <libboot/types.h>
struct PACKED page_desc {
union {
struct {
unsigned int xn : 1; // Execute never. Stops execution of page.
unsigned int one : 1; // Always one for tables
unsigned int b : 1; // cacheable
unsigned int c : 1; // Cacheable
unsigned int ap1 : 2;
unsigned int tex : 3;
unsigned int ap2 : 1;
unsigned int s : 1;
unsigned int ng : 1;
unsigned int baddr : 20;
};
uint32_t data;
};
};
typedef struct page_desc page_desc_t;
struct PACKED table_desc {
union {
struct {
int valid : 1; /* Valid mapping */
int zero1 : 1;
int zero2 : 1;
int ns : 1;
int zero3 : 1;
int domain : 4;
int imp : 1;
int baddr : 22;
};
uint32_t data;
};
};
typedef struct table_desc table_desc_t;
typedef struct {
page_desc_t entities[VMM_LV0_ENTITY_COUNT];
} ptable_t;
typedef struct pdirectory {
table_desc_t entities[VMM_LV1_ENTITY_COUNT];
} pdirectory_t;
void vm_setup(size_t kernel_vaddr, size_t kernel_paddr, size_t kernel_size);
void vm_setup_secondary_cpu();
#endif // _BOOT_VMM_VMM_H