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#include <common.h>
#include <asm/arch/mmu.h>
#include <asm/sysreg.h>
void mmu_init_r(unsigned long dest_addr)
{
uintptr_t vmr_table_addr;
/* Round monitor address down to the nearest page boundary */
dest_addr &= PAGE_ADDR_MASK;
/* Initialize TLB entry 0 to cover the monitor, and lock it */
sysreg_write(TLBEHI, dest_addr | SYSREG_BIT(TLBEHI_V));
sysreg_write(TLBELO, dest_addr | MMU_VMR_CACHE_WRBACK);
sysreg_write(MMUCR, SYSREG_BF(DRP, 0) | SYSREG_BF(DLA, 1)
| SYSREG_BIT(MMUCR_S) | SYSREG_BIT(M));
__builtin_tlbw();
/*
* Calculate the address of the VM range table in a PC-relative
* manner to make sure we hit the SDRAM and not the flash.
*/
vmr_table_addr = (uintptr_t)&mmu_vmr_table;
sysreg_write(PTBR, vmr_table_addr);
printf("VMR table @ 0x%08lx\n", vmr_table_addr);
/* Enable paging */
sysreg_write(MMUCR, SYSREG_BF(DRP, 1) | SYSREG_BF(DLA, 1)
| SYSREG_BIT(MMUCR_S) | SYSREG_BIT(M) | SYSREG_BIT(E));
}
int mmu_handle_tlb_miss(void)
{
const struct mmu_vm_range *vmr_table;
const struct mmu_vm_range *vmr;
unsigned int fault_pgno;
int first, last;
fault_pgno = sysreg_read(TLBEAR) >> PAGE_SHIFT;
vmr_table = (const struct mmu_vm_range *)sysreg_read(PTBR);
/* Do a binary search through the VM ranges */
first = 0;
last = CONFIG_SYS_NR_VM_REGIONS;
while (first < last) {
unsigned int start;
int middle;
/* Pick the entry in the middle of the remaining range */
middle = (first + last) >> 1;
vmr = &vmr_table[middle];
start = vmr->virt_pgno;
/* Do the bisection thing */
if (fault_pgno < start) {
last = middle;
} else if (fault_pgno >= (start + vmr->nr_pages)) {
first = middle + 1;
} else {
/* Got it; let's slam it into the TLB */
uint32_t tlbelo;
tlbelo = vmr->phys & ~PAGE_ADDR_MASK;
tlbelo |= fault_pgno << PAGE_SHIFT;
sysreg_write(TLBELO, tlbelo);
__builtin_tlbw();
/* Zero means success */
return 0;
}
}
/*
* Didn't find any matching entries. Return a nonzero value to
* indicate that this should be treated as a fatal exception.
*/
return -1;
}
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