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#include <lib/mmu.h>
#define CACHABLE 0x08
#define BUFFERABLE 0x04
#define NO_PERMISSIONS_REQUIRED 0b11 << 10
#define MMU_TABLE_BASE 0x00004000
void mmu_start(unsigned long base, unsigned long flags);
void mmu_section(unsigned long virtual, unsigned long physical, unsigned long flags)
{
unsigned long offset = virtual >> 20;
unsigned long* entry = (unsigned long*)(MMU_TABLE_BASE | (offset << 2));
unsigned long physval = (physical & 0xFFF00000) | (flags & 0x7FFC) | 0x00C02;
*entry = physval;
}
void mmu_init(void)
{
mmu_section(0x00000000, 0x00000000, CACHABLE | BUFFERABLE);
for (unsigned long addr = 0x00100000;; addr += 0x00100000) {
mmu_section(addr, addr, NO_PERMISSIONS_REQUIRED);
if (addr == 0x02000000)
mmu_section(addr, addr, CACHABLE | BUFFERABLE | NO_PERMISSIONS_REQUIRED);
//else if (addr == 0x3F000000)
//else
// mmu_section(addr, addr, NO_PERMISSIONS_REQUIRED);
if (addr == 0xFFF00000)
break;
}
mmu_start(MMU_TABLE_BASE,0x00000001|0x1000|0x0004);
}
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