FreeBSD-5.3/sys/i386/i386/i686_mem.c
/*-
* Copyright (c) 1999 Michael Smith <msmith@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sys/i386/i386/i686_mem.c,v 1.24 2004/07/01 07:46:28 jhb Exp $");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/memrange.h>
#include <sys/smp.h>
#include <sys/sysctl.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
/*
* i686 memory range operations
*
* This code will probably be impenetrable without reference to the
* Intel Pentium Pro documentation.
*/
static char *mem_owner_bios = "BIOS";
#define MR686_FIXMTRR (1<<0)
#define mrwithin(mr, a) \
(((a) >= (mr)->mr_base) && ((a) < ((mr)->mr_base + (mr)->mr_len)))
#define mroverlap(mra, mrb) \
(mrwithin(mra, mrb->mr_base) || mrwithin(mrb, mra->mr_base))
#define mrvalid(base, len) \
((!(base & ((1 << 12) - 1))) && /* base is multiple of 4k */ \
((len) >= (1 << 12)) && /* length is >= 4k */ \
powerof2((len)) && /* ... and power of two */ \
!((base) & ((len) - 1))) /* range is not discontiuous */
#define mrcopyflags(curr, new) (((curr) & ~MDF_ATTRMASK) | ((new) & MDF_ATTRMASK))
static int mtrrs_disabled;
TUNABLE_INT("machdep.disable_mtrrs", &mtrrs_disabled);
SYSCTL_INT(_machdep, OID_AUTO, disable_mtrrs, CTLFLAG_RDTUN,
&mtrrs_disabled, 0, "Disable i686 MTRRs.");
static void i686_mrinit(struct mem_range_softc *sc);
static int i686_mrset(struct mem_range_softc *sc,
struct mem_range_desc *mrd,
int *arg);
static void i686_mrAPinit(struct mem_range_softc *sc);
static struct mem_range_ops i686_mrops = {
i686_mrinit,
i686_mrset,
i686_mrAPinit
};
/* XXX for AP startup hook */
static u_int64_t mtrrcap, mtrrdef;
static struct mem_range_desc *mem_range_match(struct mem_range_softc *sc,
struct mem_range_desc *mrd);
static void i686_mrfetch(struct mem_range_softc *sc);
static int i686_mtrrtype(int flags);
static int i686_mrt2mtrr(int flags, int oldval);
static int i686_mtrrconflict(int flag1, int flag2);
static void i686_mrstore(struct mem_range_softc *sc);
static void i686_mrstoreone(void *arg);
static struct mem_range_desc *i686_mtrrfixsearch(struct mem_range_softc *sc,
u_int64_t addr);
static int i686_mrsetlow(struct mem_range_softc *sc,
struct mem_range_desc *mrd,
int *arg);
static int i686_mrsetvariable(struct mem_range_softc *sc,
struct mem_range_desc *mrd,
int *arg);
/* i686 MTRR type to memory range type conversion */
static int i686_mtrrtomrt[] = {
MDF_UNCACHEABLE,
MDF_WRITECOMBINE,
MDF_UNKNOWN,
MDF_UNKNOWN,
MDF_WRITETHROUGH,
MDF_WRITEPROTECT,
MDF_WRITEBACK
};
#define MTRRTOMRTLEN (sizeof(i686_mtrrtomrt) / sizeof(i686_mtrrtomrt[0]))
static int
i686_mtrr2mrt(int val) {
if (val < 0 || val >= MTRRTOMRTLEN)
return MDF_UNKNOWN;
return i686_mtrrtomrt[val];
}
/*
* i686 MTRR conflicts. Writeback and uncachable may overlap.
*/
static int
i686_mtrrconflict(int flag1, int flag2) {
flag1 &= MDF_ATTRMASK;
flag2 &= MDF_ATTRMASK;
if (flag1 == flag2 ||
(flag1 == MDF_WRITEBACK && flag2 == MDF_UNCACHEABLE) ||
(flag2 == MDF_WRITEBACK && flag1 == MDF_UNCACHEABLE))
return 0;
return 1;
}
/*
* Look for an exactly-matching range.
*/
static struct mem_range_desc *
mem_range_match(struct mem_range_softc *sc, struct mem_range_desc *mrd)
{
struct mem_range_desc *cand;
int i;
for (i = 0, cand = sc->mr_desc; i < sc->mr_ndesc; i++, cand++)
if ((cand->mr_base == mrd->mr_base) &&
(cand->mr_len == mrd->mr_len))
return(cand);
return(NULL);
}
/*
* Fetch the current mtrr settings from the current CPU (assumed to all
* be in sync in the SMP case). Note that if we are here, we assume
* that MTRRs are enabled, and we may or may not have fixed MTRRs.
*/
static void
i686_mrfetch(struct mem_range_softc *sc)
{
struct mem_range_desc *mrd;
u_int64_t msrv;
int i, j, msr;
mrd = sc->mr_desc;
/* Get fixed-range MTRRs */
if (sc->mr_cap & MR686_FIXMTRR) {
msr = MSR_MTRR64kBase;
for (i = 0; i < (MTRR_N64K / 8); i++, msr++) {
msrv = rdmsr(msr);
for (j = 0; j < 8; j++, mrd++) {
mrd->mr_flags = (mrd->mr_flags & ~MDF_ATTRMASK) |
i686_mtrr2mrt(msrv & 0xff) |
MDF_ACTIVE;
if (mrd->mr_owner[0] == 0)
strcpy(mrd->mr_owner, mem_owner_bios);
msrv = msrv >> 8;
}
}
msr = MSR_MTRR16kBase;
for (i = 0; i < (MTRR_N16K / 8); i++, msr++) {
msrv = rdmsr(msr);
for (j = 0; j < 8; j++, mrd++) {
mrd->mr_flags = (mrd->mr_flags & ~MDF_ATTRMASK) |
i686_mtrr2mrt(msrv & 0xff) |
MDF_ACTIVE;
if (mrd->mr_owner[0] == 0)
strcpy(mrd->mr_owner, mem_owner_bios);
msrv = msrv >> 8;
}
}
msr = MSR_MTRR4kBase;
for (i = 0; i < (MTRR_N4K / 8); i++, msr++) {
msrv = rdmsr(msr);
for (j = 0; j < 8; j++, mrd++) {
mrd->mr_flags = (mrd->mr_flags & ~MDF_ATTRMASK) |
i686_mtrr2mrt(msrv & 0xff) |
MDF_ACTIVE;
if (mrd->mr_owner[0] == 0)
strcpy(mrd->mr_owner, mem_owner_bios);
msrv = msrv >> 8;
}
}
}
/* Get remainder which must be variable MTRRs */
msr = MSR_MTRRVarBase;
for (; (mrd - sc->mr_desc) < sc->mr_ndesc; msr += 2, mrd++) {
msrv = rdmsr(msr);
mrd->mr_flags = (mrd->mr_flags & ~MDF_ATTRMASK) |
i686_mtrr2mrt(msrv & 0xff);
mrd->mr_base = msrv & 0x0000000ffffff000LL;
msrv = rdmsr(msr + 1);
mrd->mr_flags = (msrv & 0x800) ?
(mrd->mr_flags | MDF_ACTIVE) :
(mrd->mr_flags & ~MDF_ACTIVE);
/* Compute the range from the mask. Ick. */
mrd->mr_len = (~(msrv & 0x0000000ffffff000LL) & 0x0000000fffffffffLL) + 1;
if (!mrvalid(mrd->mr_base, mrd->mr_len))
mrd->mr_flags |= MDF_BOGUS;
/* If unclaimed and active, must be the BIOS */
if ((mrd->mr_flags & MDF_ACTIVE) && (mrd->mr_owner[0] == 0))
strcpy(mrd->mr_owner, mem_owner_bios);
}
}
/*
* Return the MTRR memory type matching a region's flags
*/
static int
i686_mtrrtype(int flags)
{
int i;
flags &= MDF_ATTRMASK;
for (i = 0; i < MTRRTOMRTLEN; i++) {
if (i686_mtrrtomrt[i] == MDF_UNKNOWN)
continue;
if (flags == i686_mtrrtomrt[i])
return(i);
}
return(-1);
}
static int
i686_mrt2mtrr(int flags, int oldval)
{
int val;
if ((val = i686_mtrrtype(flags)) == -1)
return oldval & 0xff;
return val & 0xff;
}
/*
* Update running CPU(s) MTRRs to match the ranges in the descriptor
* list.
*
* XXX Must be called with interrupts enabled.
*/
static void
i686_mrstore(struct mem_range_softc *sc)
{
#ifdef SMP
/*
* We should use ipi_all_but_self() to call other CPUs into a
* locking gate, then call a target function to do this work.
* The "proper" solution involves a generalised locking gate
* implementation, not ready yet.
*/
smp_rendezvous(NULL, i686_mrstoreone, NULL, (void *)sc);
#else
disable_intr(); /* disable interrupts */
i686_mrstoreone((void *)sc);
enable_intr();
#endif
}
/*
* Update the current CPU's MTRRs with those represented in the
* descriptor list. Note that we do this wholesale rather than
* just stuffing one entry; this is simpler (but slower, of course).
*/
static void
i686_mrstoreone(void *arg)
{
struct mem_range_softc *sc = (struct mem_range_softc *)arg;
struct mem_range_desc *mrd;
u_int64_t omsrv, msrv;
int i, j, msr;
u_int cr4save;
mrd = sc->mr_desc;
cr4save = rcr4(); /* save cr4 */
if (cr4save & CR4_PGE)
load_cr4(cr4save & ~CR4_PGE);
load_cr0((rcr0() & ~CR0_NW) | CR0_CD); /* disable caches (CD = 1, NW = 0) */
wbinvd(); /* flush caches, TLBs */
wrmsr(MSR_MTRRdefType, rdmsr(MSR_MTRRdefType) & ~0x800); /* disable MTRRs (E = 0) */
/* Set fixed-range MTRRs */
if (sc->mr_cap & MR686_FIXMTRR) {
msr = MSR_MTRR64kBase;
for (i = 0; i < (MTRR_N64K / 8); i++, msr++) {
msrv = 0;
omsrv = rdmsr(msr);
for (j = 7; j >= 0; j--) {
msrv = msrv << 8;
msrv |= i686_mrt2mtrr((mrd + j)->mr_flags, omsrv >> (j*8));
}
wrmsr(msr, msrv);
mrd += 8;
}
msr = MSR_MTRR16kBase;
for (i = 0; i < (MTRR_N16K / 8); i++, msr++) {
msrv = 0;
omsrv = rdmsr(msr);
for (j = 7; j >= 0; j--) {
msrv = msrv << 8;
msrv |= i686_mrt2mtrr((mrd + j)->mr_flags, omsrv >> (j*8));
}
wrmsr(msr, msrv);
mrd += 8;
}
msr = MSR_MTRR4kBase;
for (i = 0; i < (MTRR_N4K / 8); i++, msr++) {
msrv = 0;
omsrv = rdmsr(msr);
for (j = 7; j >= 0; j--) {
msrv = msrv << 8;
msrv |= i686_mrt2mtrr((mrd + j)->mr_flags, omsrv >> (j*8));
}
wrmsr(msr, msrv);
mrd += 8;
}
}
/* Set remainder which must be variable MTRRs */
msr = MSR_MTRRVarBase;
for (; (mrd - sc->mr_desc) < sc->mr_ndesc; msr += 2, mrd++) {
/* base/type register */
omsrv = rdmsr(msr);
if (mrd->mr_flags & MDF_ACTIVE) {
msrv = mrd->mr_base & 0x0000000ffffff000LL;
msrv |= i686_mrt2mtrr(mrd->mr_flags, omsrv);
} else {
msrv = 0;
}
wrmsr(msr, msrv);
/* mask/active register */
if (mrd->mr_flags & MDF_ACTIVE) {
msrv = 0x800 | (~(mrd->mr_len - 1) & 0x0000000ffffff000LL);
} else {
msrv = 0;
}
wrmsr(msr + 1, msrv);
}
wbinvd(); /* flush caches, TLBs */
wrmsr(MSR_MTRRdefType, rdmsr(MSR_MTRRdefType) | 0x800); /* restore MTRR state */
load_cr0(rcr0() & ~(CR0_CD | CR0_NW)); /* enable caches CD = 0 and NW = 0 */
load_cr4(cr4save); /* restore cr4 */
}
/*
* Hunt for the fixed MTRR referencing (addr)
*/
static struct mem_range_desc *
i686_mtrrfixsearch(struct mem_range_softc *sc, u_int64_t addr)
{
struct mem_range_desc *mrd;
int i;
for (i = 0, mrd = sc->mr_desc; i < (MTRR_N64K + MTRR_N16K + MTRR_N4K); i++, mrd++)
if ((addr >= mrd->mr_base) && (addr < (mrd->mr_base + mrd->mr_len)))
return(mrd);
return(NULL);
}
/*
* Try to satisfy the given range request by manipulating the fixed MTRRs that
* cover low memory.
*
* Note that we try to be generous here; we'll bloat the range out to the
* next higher/lower boundary to avoid the consumer having to know too much
* about the mechanisms here.
*
* XXX note that this will have to be updated when we start supporting "busy" ranges.
*/
static int
i686_mrsetlow(struct mem_range_softc *sc, struct mem_range_desc *mrd, int *arg)
{
struct mem_range_desc *first_md, *last_md, *curr_md;
/* range check */
if (((first_md = i686_mtrrfixsearch(sc, mrd->mr_base)) == NULL) ||
((last_md = i686_mtrrfixsearch(sc, mrd->mr_base + mrd->mr_len - 1)) == NULL))
return(EINVAL);
/* check we aren't doing something risky */
if (!(mrd->mr_flags & MDF_FORCE))
for (curr_md = first_md; curr_md <= last_md; curr_md++) {
if ((curr_md->mr_flags & MDF_ATTRMASK) == MDF_UNKNOWN)
return (EACCES);
}
/* set flags, clear set-by-firmware flag */
for (curr_md = first_md; curr_md <= last_md; curr_md++) {
curr_md->mr_flags = mrcopyflags(curr_md->mr_flags & ~MDF_FIRMWARE, mrd->mr_flags);
bcopy(mrd->mr_owner, curr_md->mr_owner, sizeof(mrd->mr_owner));
}
return(0);
}
/*
* Modify/add a variable MTRR to satisfy the request.
*
* XXX needs to be updated to properly support "busy" ranges.
*/
static int
i686_mrsetvariable(struct mem_range_softc *sc, struct mem_range_desc *mrd, int *arg)
{
struct mem_range_desc *curr_md, *free_md;
int i;
/*
* Scan the currently active variable descriptors, look for
* one we exactly match (straight takeover) and for possible
* accidental overlaps.
* Keep track of the first empty variable descriptor in case we
* can't perform a takeover.
*/
i = (sc->mr_cap & MR686_FIXMTRR) ? MTRR_N64K + MTRR_N16K + MTRR_N4K : 0;
curr_md = sc->mr_desc + i;
free_md = NULL;
for (; i < sc->mr_ndesc; i++, curr_md++) {
if (curr_md->mr_flags & MDF_ACTIVE) {
/* exact match? */
if ((curr_md->mr_base == mrd->mr_base) &&
(curr_md->mr_len == mrd->mr_len)) {
/* whoops, owned by someone */
if (curr_md->mr_flags & MDF_BUSY)
return(EBUSY);
/* check we aren't doing something risky */
if (!(mrd->mr_flags & MDF_FORCE) &&
((curr_md->mr_flags & MDF_ATTRMASK) == MDF_UNKNOWN))
return (EACCES);
/* Ok, just hijack this entry */
free_md = curr_md;
break;
}
/* non-exact overlap ? */
if (mroverlap(curr_md, mrd)) {
/* between conflicting region types? */
if (i686_mtrrconflict(curr_md->mr_flags, mrd->mr_flags))
return(EINVAL);
}
} else if (free_md == NULL) {
free_md = curr_md;
}
}
/* got somewhere to put it? */
if (free_md == NULL)
return(ENOSPC);
/* Set up new descriptor */
free_md->mr_base = mrd->mr_base;
free_md->mr_len = mrd->mr_len;
free_md->mr_flags = mrcopyflags(MDF_ACTIVE, mrd->mr_flags);
bcopy(mrd->mr_owner, free_md->mr_owner, sizeof(mrd->mr_owner));
return(0);
}
/*
* Handle requests to set memory range attributes by manipulating MTRRs.
*
*/
static int
i686_mrset(struct mem_range_softc *sc, struct mem_range_desc *mrd, int *arg)
{
struct mem_range_desc *targ;
int error = 0;
switch(*arg) {
case MEMRANGE_SET_UPDATE:
/* make sure that what's being asked for is even possible at all */
if (!mrvalid(mrd->mr_base, mrd->mr_len) ||
i686_mtrrtype(mrd->mr_flags) == -1)
return(EINVAL);
#define FIXTOP ((MTRR_N64K * 0x10000) + (MTRR_N16K * 0x4000) + (MTRR_N4K * 0x1000))
/* are the "low memory" conditions applicable? */
if ((sc->mr_cap & MR686_FIXMTRR) &&
((mrd->mr_base + mrd->mr_len) <= FIXTOP)) {
if ((error = i686_mrsetlow(sc, mrd, arg)) != 0)
return(error);
} else {
/* it's time to play with variable MTRRs */
if ((error = i686_mrsetvariable(sc, mrd, arg)) != 0)
return(error);
}
break;
case MEMRANGE_SET_REMOVE:
if ((targ = mem_range_match(sc, mrd)) == NULL)
return(ENOENT);
if (targ->mr_flags & MDF_FIXACTIVE)
return(EPERM);
if (targ->mr_flags & MDF_BUSY)
return(EBUSY);
targ->mr_flags &= ~MDF_ACTIVE;
targ->mr_owner[0] = 0;
break;
default:
return(EOPNOTSUPP);
}
/* update the hardware */
i686_mrstore(sc);
i686_mrfetch(sc); /* refetch to see where we're at */
return(0);
}
/*
* Work out how many ranges we support, initialise storage for them,
* fetch the initial settings.
*/
static void
i686_mrinit(struct mem_range_softc *sc)
{
struct mem_range_desc *mrd;
int nmdesc = 0;
int i;
mtrrcap = rdmsr(MSR_MTRRcap);
mtrrdef = rdmsr(MSR_MTRRdefType);
/* For now, bail out if MTRRs are not enabled */
if (!(mtrrdef & 0x800)) {
if (bootverbose)
printf("CPU supports MTRRs but not enabled\n");
return;
}
nmdesc = mtrrcap & 0xff;
if (bootverbose)
printf("Pentium Pro MTRR support enabled\n");
/* If fixed MTRRs supported and enabled */
if ((mtrrcap & 0x100) && (mtrrdef & 0x400)) {
sc->mr_cap = MR686_FIXMTRR;
nmdesc += MTRR_N64K + MTRR_N16K + MTRR_N4K;
}
sc->mr_desc =
(struct mem_range_desc *)malloc(nmdesc * sizeof(struct mem_range_desc),
M_MEMDESC, M_WAITOK | M_ZERO);
sc->mr_ndesc = nmdesc;
mrd = sc->mr_desc;
/* Populate the fixed MTRR entries' base/length */
if (sc->mr_cap & MR686_FIXMTRR) {
for (i = 0; i < MTRR_N64K; i++, mrd++) {
mrd->mr_base = i * 0x10000;
mrd->mr_len = 0x10000;
mrd->mr_flags = MDF_FIXBASE | MDF_FIXLEN | MDF_FIXACTIVE;
}
for (i = 0; i < MTRR_N16K; i++, mrd++) {
mrd->mr_base = i * 0x4000 + 0x80000;
mrd->mr_len = 0x4000;
mrd->mr_flags = MDF_FIXBASE | MDF_FIXLEN | MDF_FIXACTIVE;
}
for (i = 0; i < MTRR_N4K; i++, mrd++) {
mrd->mr_base = i * 0x1000 + 0xc0000;
mrd->mr_len = 0x1000;
mrd->mr_flags = MDF_FIXBASE | MDF_FIXLEN | MDF_FIXACTIVE;
}
}
/*
* Get current settings, anything set now is considered to have
* been set by the firmware. (XXX has something already played here?)
*/
i686_mrfetch(sc);
mrd = sc->mr_desc;
for (i = 0; i < sc->mr_ndesc; i++, mrd++) {
if (mrd->mr_flags & MDF_ACTIVE)
mrd->mr_flags |= MDF_FIRMWARE;
}
}
/*
* Initialise MTRRs on an AP after the BSP has run the init code.
*/
static void
i686_mrAPinit(struct mem_range_softc *sc)
{
i686_mrstoreone((void *)sc); /* set MTRRs to match BSP */
wrmsr(MSR_MTRRdefType, mtrrdef); /* set MTRR behaviour to match BSP */
}
static void
i686_mem_drvinit(void *unused)
{
/* Try for i686 MTRRs */
if (!mtrrs_disabled && (cpu_feature & CPUID_MTRR) &&
((cpu_id & 0xf00) == 0x600 || (cpu_id & 0xf00) == 0xf00) &&
((strcmp(cpu_vendor, "GenuineIntel") == 0) ||
(strcmp(cpu_vendor, "AuthenticAMD") == 0))) {
mem_range_softc.mr_op = &i686_mrops;
}
}
SYSINIT(i686memdev,SI_SUB_DRIVERS,SI_ORDER_FIRST,i686_mem_drvinit,NULL)