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kernel: get rid of 36 bit Paerange mask in mtrr (supporting machines with more than 64GB of memory)

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This commit is contained in:
cinap_lenrek 2017-09-27 13:58:00 +02:00
parent b8d4c6ff17
commit dad00a77da
1 changed files with 0 additions and 17 deletions
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17
sys/src/9/pc/mtrr.c
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@ -34,8 +34,6 @@ enum {
Extl2,
Extapm,
Extaddrsz,
Paerange = 1LL << 36,
};
enum {
@ -116,18 +114,9 @@ physmask(void)
cpuid(Extaddrsz, regs);
mask = (1LL << (regs[0] & 0xFF)) - 1; /* ax */
}
mask &= Paerange - 1; /* x86 sanity */
return mask;
}
/* limit physical addresses to 36 bits on the x86 */
static void
sanity(Mtrreg *mtrr)
{
mtrr->base &= Paerange - 1;
mtrr->mask &= Paerange - 1;
}
static int
ispow2(uvlong ul)
{
@ -138,7 +127,6 @@ ispow2(uvlong ul)
static int
mtrrdec(Mtrreg *mtrr, uvlong *ptr, uvlong *size, int *type)
{
sanity(mtrr);
*ptr = mtrr->base & ~(BY2PG-1);
*type = mtrr->base & 0xff;
*size = (physmask() ^ (mtrr->mask & ~(BY2PG-1))) + 1;
@ -150,7 +138,6 @@ mtrrenc(Mtrreg *mtrr, uvlong ptr, uvlong size, int type, int ok)
{
mtrr->base = ptr | (type & 0xff);
mtrr->mask = (physmask() & ~(size - 1)) | (ok? 1<<11: 0);
sanity(mtrr);
}
/*
@ -162,13 +149,11 @@ mtrrget(Mtrreg *mtrr, uint i)
{
rdmsr(MTRRPhysBase0 + 2*i, &mtrr->base);
rdmsr(MTRRPhysMask0 + 2*i, &mtrr->mask);
sanity(mtrr);
}
static void
mtrrput(Mtrreg *mtrr, uint i)
{
sanity(mtrr);
wrmsr(MTRRPhysBase0 + 2*i, mtrr->base);
wrmsr(MTRRPhysMask0 + 2*i, mtrr->mask);
}
@ -275,8 +260,6 @@ mtrr0(uvlong base, uvlong size, char *tstr)
return "mtrrs not supported";
if(base & (BY2PG-1) || size & (BY2PG-1) || size == 0)
return "mtrr base or size not 4k aligned or zero size";
if(base + size >= Paerange)
return "mtrr range exceeds 36 bits";
if(!ispow2(size))
return "mtrr size not power of 2";
if(base & (size - 1))