forked from cahirwpz/mimiker
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pmap.c
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pmap.c
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#include <pmap.h>
#include <malloc.h>
#include <libkern.h>
#include <mips/cpu.h>
#include <tlb.h>
#define PTE_INDEX(x) (((x) & 0xfffff000) >> 12)
#define PDE_INDEX(x) (((x) & 0xffc00000) >> 22)
static pmap_t *active_pmap = NULL;
void pmap_init(pmap_t *pmap) {
pmap->pte = (pte_t *)PTE_BASE;
pmap->pde_page = pm_alloc(1);
pmap->pde = (pte_t *)pmap->pde_page->vaddr;
TAILQ_INIT(&pmap->pte_pages);
}
void pmap_delete(pmap_t *pmap) {
while (!TAILQ_EMPTY(&pmap->pte_pages)) {
vm_page_t *pg = TAILQ_FIRST(&pmap->pte_pages);
TAILQ_REMOVE(&pmap->pte_pages, pg, pt.list);
pm_free(pg);
}
pm_free(pmap->pde_page);
}
static void pde_map(pmap_t *pmap, vaddr_t vaddr) {
uint32_t pde_index = PDE_INDEX(vaddr);
if (!(pmap->pde[pde_index] & V_MASK)) {
/* part of page table isn't located in memory */
vm_page_t *pg = pm_alloc(1);
TAILQ_INSERT_TAIL(&pmap->pte_pages, pg, pt.list);
ENTRYLO_SET_PADDR(pmap->pde[pde_index], pg->paddr);
ENTRYLO_SET_V(pmap->pde[pde_index], 1);
ENTRYLO_SET_D(pmap->pde[pde_index], 1);
}
/* make sure proper address is in tlb */
pde_index &= ~1;
tlbhi_t entryhi = (PTE_BASE + pde_index * PAGESIZE) | pmap->asid;
tlblo_t entrylo0 = pmap->pde[pde_index];
tlblo_t entrylo1 = pmap->pde[pde_index + 1];
tlb_overwrite_random(entryhi, entrylo0, entrylo1);
}
static void pt_map(pmap_t *pmap, vm_addr_t vaddr, pm_addr_t paddr,
uint8_t flags) {
pde_map(pmap, vaddr);
pte_t entry = flags;
uint32_t pt_index = PTE_INDEX(vaddr);
ENTRYLO_SET_PADDR(entry , paddr);
pmap->pte[pt_index] = entry;
/* invalidate proper entry in tlb */
tlbhi_t entryhi = 0;
ENTRYHI_SET_VADDR(entryhi, vaddr);
ENTRYHI_SET_ASID(entryhi, pmap->asid);
tlb_invalidate(entryhi);
}
void pmap_map(pmap_t *pmap, vm_addr_t vaddr, pm_addr_t paddr, size_t npages,
uint8_t flags) {
for (size_t i = 0; i < npages; i++)
pt_map(pmap, vaddr + i * PAGESIZE, paddr + i * PAGESIZE, flags);
}
void pmap_unmap(pmap_t *pmap, vm_addr_t vaddr, size_t npages) {
panic("unimplemented");
}
void set_active_pmap(pmap_t *pmap) {
active_pmap = pmap;
mips32_set_c0(C0_ENTRYHI, pmap->asid);
}
pmap_t *get_active_pmap() {
return active_pmap;
}
#ifdef _KERNELSPACE
int main() { /* Simple test */
pmap_t pmap;
pmap_init(&pmap);
pmap.asid = 10;
set_active_pmap(&pmap);
vm_page_t *pg1 = pm_alloc(4);
vaddr_t ex_addr = PAGESIZE * 10;
pmap_map(&pmap, ex_addr, pg1->paddr, pg1->size, PMAP_VALID | PMAP_DIRTY);
int *x = (int *) ex_addr;
for (int i = 0; i < 1024 * pg1->size; i++)
*(x + i) = i;
for (int i = 0; i < 1024 * pg1->size; i++)
assert(*(x + i) == i);
vm_page_t *pg2 = pm_alloc(1);
ex_addr = PAGESIZE * 2000;
pmap_map(&pmap, ex_addr, pg2->paddr, pg2->size, PMAP_VALID | PMAP_DIRTY);
x = (int *) ex_addr;
for (int i = 0; i < 1024 * pg2->size; i++)
*(x + i) = i;
for (int i = 0; i < 1024 * pg2->size; i++)
assert(*(x + i) == i);
pm_free(pg1);
pm_free(pg2);
pmap_delete(&pmap);
kprintf("Tests passed\n");
return 0;
}
#endif /* _KERNELSPACE */