ref: 34885a7d22296fc47a2bcf7f02bb6b1953ea3d24
dir: /sys/src/9/lx2k/mem.c/
#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#define INITMAP (ROUND((uintptr)end + BY2PG, PGLSZ(1))-KZERO)
/*
* Create initial identity map in top-level page table
* (L1BOT) for TTBR0. This page table is only used until
* mmu1init() loads m->mmutop.
*/
void
mmuidmap(uintptr *l1bot)
{
uintptr pa, pe, attr;
/* VDRAM */
attr = PTEWRITE | PTEAF | PTEKERNEL | PTEUXN | PTESH(SHARE_INNER);
pe = -KZERO;
for(pa = VDRAM - KZERO; pa < pe; pa += PGLSZ(PTLEVELS-1))
l1bot[PTLX(pa, PTLEVELS-1)] = pa | PTEVALID | PTEBLOCK | attr;
}
/*
* Create initial shared kernel page table (L1) for TTBR1.
* This page table coveres the INITMAP and VIRTIO,
* and later we fill the ram mappings in meminit().
*/
void
mmu0init(uintptr *l1)
{
uintptr va, pa, pe, attr;
/* DRAM - INITMAP */
attr = PTEWRITE | PTEAF | PTEKERNEL | PTEUXN | PTESH(SHARE_INNER);
pe = INITMAP;
for(pa = VDRAM - KZERO, va = VDRAM; pa < pe; pa += PGLSZ(1), va += PGLSZ(1))
l1[PTL1X(va, 1)] = pa | PTEVALID | PTEBLOCK | attr;
/* VIRTIO */
attr = PTEWRITE | PTEAF | PTEKERNEL | PTEUXN | PTEPXN | PTESH(SHARE_OUTER) | PTEDEVICE;
pe = PHYSIOEND;
for(pa = PHYSIO, va = VIRTIO; pa < pe; pa += PGLSZ(1), va += PGLSZ(1)){
if(((pa|va) & PGLSZ(1)-1) != 0){
l1[PTL1X(va, 1)] = (uintptr)l1 | PTEVALID | PTETABLE;
for(; pa < pe && ((va|pa) & PGLSZ(1)-1) != 0; pa += PGLSZ(0), va += PGLSZ(0)){
assert(l1[PTLX(va, 0)] == 0);
l1[PTLX(va, 0)] = pa | PTEVALID | PTEPAGE | attr;
}
break;
}
l1[PTL1X(va, 1)] = pa | PTEVALID | PTEBLOCK | attr;
}
if(PTLEVELS > 2)
for(va = KSEG0; va != 0; va += PGLSZ(2))
l1[PTL1X(va, 2)] = (uintptr)&l1[L1TABLEX(va, 1)] | PTEVALID | PTETABLE;
if(PTLEVELS > 3)
for(va = KSEG0; va != 0; va += PGLSZ(3))
l1[PTL1X(va, 3)] = (uintptr)&l1[L1TABLEX(va, 2)] | PTEVALID | PTETABLE;
}
void
meminit(void)
{
char *p;
/* GPP DRAM Region #1 */
conf.mem[0].base = PGROUND((uintptr)end - KZERO);
conf.mem[0].limit = 0x100000000ULL;
kmapram(conf.mem[0].base, conf.mem[0].limit);
conf.mem[0].npage = (conf.mem[0].limit - conf.mem[0].base)/BY2PG;
if(p = getconf("*maxmem")){
/* GPP DRAM Region #2 */
conf.mem[1].base = 0x2080000000ULL;
conf.mem[1].limit = strtoull(p, 0, 0);
conf.mem[1].npage = (conf.mem[1].limit - conf.mem[1].base)/BY2PG;
}
}