void
mmuinit(void)
{
PTE *l1, *l2;
uintptr pa, va;
l1 = (PTE*)PADDR(L1);
l2 = (PTE*)PADDR(L2);
/* map all of ram at KZERO */
va = KZERO;
for(pa = PHYSDRAM; pa < PHYSDRAM+DRAMSIZE; pa += MiB){
l1[L1X(va)] = pa|Dom0|L1AP(Krw)|Section|Cached|Buffered;
va += MiB;
}
/* identity map first MB of ram so mmu can be enabled */
l1[L1X(PHYSDRAM)] = PHYSDRAM|Dom0|L1AP(Krw)|Section|Cached|Buffered;
/* map i/o registers */
va = VIRTIO;
for(pa = PHYSIO; pa < PHYSIO+IOSIZE; pa += MiB){
l1[L1X(va)] = pa|Dom0|L1AP(Krw)|Section;
va += MiB;
}
/* double map exception vectors at top of virtual memory */
va = HVECTORS;
l1[L1X(va)] = (uintptr)l2|Dom0|Coarse;
l2[L2X(va)] = PHYSDRAM|L2AP(Krw)|Small;
}
void
mmuinit(void)
{
uintptr pa;
PTE *l1, *l2;
pa = ttbget();
l1 = KADDR(pa);
/* redundant with l.s; only covers first MB of 17MB */
l1[L1X(VIRTIO)] = PHYSIO|Dom0|L1AP(Krw)|Section;
idmap(l1, PHYSETHER); /* igep 9221 ethernet regs */
idmap(l1, PHYSL4PROT);
idmap(l1, PHYSL3);
idmap(l1, PHYSSMS);
idmap(l1, PHYSDRC);
idmap(l1, PHYSGPMC);
/* map high vectors to start of dram, but only 4K, not 1MB */
pa -= MACHSIZE+2*1024;
l2 = KADDR(pa);
memset(l2, 0, 1024);
/* vectors step on u-boot, but so do page tables */
l2[L2X(HVECTORS)] = PHYSDRAM|L2AP(Krw)|Small;
l1[L1X(HVECTORS)] = pa|Dom0|Coarse; /* vectors -> ttb-machsize-2k */
coherence();
cacheuwbinv();
l2cacheuwbinv();
mmuinvalidate();
m->mmul1 = l1;
// mmudump(l1); /* DEBUG */
}
void
putmmu(uintptr va, uintptr pa, Page* page)
{
int x;
Page *pg;
PTE *l1, *pte;
x = L1X(va);
l1 = &m->mmul1[x];
if(*l1 == Fault){
/* wasteful - l2 pages only have 256 entries - fix */
if(up->mmul2cache == nil){
/* auxpg since we don't need much? memset if so */
pg = newpage(1, 0, 0);
pg->va = VA(kmap(pg));
}
else{
pg = up->mmul2cache;
up->mmul2cache = pg->next;
memset(UINT2PTR(pg->va), 0, BY2PG);
}
pg->daddr = x;
pg->next = up->mmul2;
up->mmul2 = pg;
/* force l2 page to memory */
cachedwbse((void *)pg->va, BY2PG);
*l1 = PPN(pg->pa)|Dom0|Coarse;
cachedwbse(l1, sizeof *l1);
if(x >= m->mmul1lo && x < m->mmul1hi){
if(x+1 - m->mmul1lo < m->mmul1hi - x)
m->mmul1lo = x+1;
else
m->mmul1hi = x;
}
}
pte = UINT2PTR(KADDR(PPN(*l1)));
/* protection bits are
* PTERONLY|PTEVALID;
* PTEWRITE|PTEVALID;
* PTEWRITE|PTEUNCACHED|PTEVALID;
*/
x = Small;
if(!(pa & PTEUNCACHED))
x |= Cached|Buffered;
if(pa & PTEWRITE)
x |= L2AP(Urw);
else
x |= L2AP(Uro);
pte[L2X(va)] = PPN(pa)|x;
cachedwbse(&pte[L2X(va)], sizeof pte[0]);
/* clear out the current entry */
mmuinvalidateaddr(PPN(va));
/* write back dirty entries - we need this because the pio() in
* fault.c is writing via a different virt addr and won't clean
* its changes out of the dcache. Page coloring doesn't work
* on this mmu because the virtual cache is set associative
* rather than direct mapped.
*/
cachedwbinv();
if(page->txtflush){
cacheiinv();
page->txtflush = 0;
}
checkmmu(va, PPN(pa));
}
