freebsd-skq/sys/powerpc/pseries/mmu_phyp.c
Justin Hibbits 10d0cdfc6e Add support for powernv POWER9 MMU initialization
The POWER9 MMU (PowerISA 3.0) is slightly different from current
configurations, using a partition table even for hypervisor mode, and
dropping the SDR1 register.  Key off the newly early-enabled CPU features
flags for the new architecture, and configure the MMU appropriately.

The POWER9 MMU ignores the "PSIZ" field in the PTCR, and expects a 64kB
table.  As we are enabled for powernv (hypervisor mode, no VMs), only
initialize partition table entry 0, and zero out the rest.  The actual
contents of the register are identical to SDR1 from previous architectures.

Along with this, fix a bug in the page table allocation with very large
memory.  The table can be allocated on any 256k boundary.  The
bootstrap_alloc alignment argument is an int, and with large amounts of
memory passing the size of the table as the alignment will overflow an
integer.  Hard-code the alignment at 256k as wider alignment is not
necessary.

Reviewed by:	nwhitehorn
Tested by:	Breno Leitao
Relnotes:	Yes
2018-05-05 16:00:02 +00:00

475 lines
13 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (C) 2010 Andreas Tobler
* 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 ``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 TOOLS GMBH 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("$FreeBSD$");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/ktr.h>
#include <sys/lock.h>
#include <sys/rmlock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/vmmeter.h>
#include <dev/ofw/openfirm.h>
#include <machine/ofw_machdep.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_extern.h>
#include <vm/vm_pageout.h>
#include <vm/uma.h>
#include <powerpc/aim/mmu_oea64.h>
#include "mmu_if.h"
#include "moea64_if.h"
#include "phyp-hvcall.h"
static struct rmlock mphyp_eviction_lock;
/*
* Kernel MMU interface
*/
static void mphyp_bootstrap(mmu_t mmup, vm_offset_t kernelstart,
vm_offset_t kernelend);
static void mphyp_cpu_bootstrap(mmu_t mmup, int ap);
static int64_t mphyp_pte_synch(mmu_t, struct pvo_entry *pvo);
static int64_t mphyp_pte_clear(mmu_t, struct pvo_entry *pvo, uint64_t ptebit);
static int64_t mphyp_pte_unset(mmu_t, struct pvo_entry *pvo);
static int mphyp_pte_insert(mmu_t, struct pvo_entry *pvo);
static mmu_method_t mphyp_methods[] = {
MMUMETHOD(mmu_bootstrap, mphyp_bootstrap),
MMUMETHOD(mmu_cpu_bootstrap, mphyp_cpu_bootstrap),
MMUMETHOD(moea64_pte_synch, mphyp_pte_synch),
MMUMETHOD(moea64_pte_clear, mphyp_pte_clear),
MMUMETHOD(moea64_pte_unset, mphyp_pte_unset),
MMUMETHOD(moea64_pte_insert, mphyp_pte_insert),
/* XXX: pmap_copy_page, pmap_init_page with H_PAGE_INIT */
{ 0, 0 }
};
MMU_DEF_INHERIT(pseries_mmu, "mmu_phyp", mphyp_methods, 0, oea64_mmu);
static int brokenkvm = 0;
static void
print_kvm_bug_warning(void *data)
{
if (brokenkvm)
printf("WARNING: Running on a broken hypervisor that does "
"not support mandatory H_CLEAR_MOD and H_CLEAR_REF "
"hypercalls. Performance will be suboptimal.\n");
}
SYSINIT(kvmbugwarn1, SI_SUB_COPYRIGHT, SI_ORDER_THIRD + 1,
print_kvm_bug_warning, NULL);
SYSINIT(kvmbugwarn2, SI_SUB_LAST, SI_ORDER_THIRD + 1, print_kvm_bug_warning,
NULL);
static void
mphyp_bootstrap(mmu_t mmup, vm_offset_t kernelstart, vm_offset_t kernelend)
{
uint64_t final_pteg_count = 0;
char buf[8];
uint32_t prop[2];
uint32_t nptlp, shift = 0, slb_encoding = 0;
uint32_t lp_size, lp_encoding;
struct lpte old;
uint64_t vsid;
phandle_t dev, node, root;
int idx, len, res;
rm_init(&mphyp_eviction_lock, "pte eviction");
moea64_early_bootstrap(mmup, kernelstart, kernelend);
root = OF_peer(0);
dev = OF_child(root);
while (dev != 0) {
res = OF_getprop(dev, "name", buf, sizeof(buf));
if (res > 0 && strcmp(buf, "cpus") == 0)
break;
dev = OF_peer(dev);
}
node = OF_child(dev);
while (node != 0) {
res = OF_getprop(node, "device_type", buf, sizeof(buf));
if (res > 0 && strcmp(buf, "cpu") == 0)
break;
node = OF_peer(node);
}
res = OF_getencprop(node, "ibm,pft-size", prop, sizeof(prop));
if (res <= 0)
panic("mmu_phyp: unknown PFT size");
final_pteg_count = 1 << prop[1];
res = OF_getencprop(node, "ibm,slb-size", prop, sizeof(prop[0]));
if (res > 0)
n_slbs = prop[0];
moea64_pteg_count = final_pteg_count / sizeof(struct lpteg);
/* Clear any old page table entries */
for (idx = 0; idx < moea64_pteg_count*8; idx++) {
phyp_pft_hcall(H_READ, 0, idx, 0, 0, &old.pte_hi,
&old.pte_lo, &old.pte_lo);
vsid = (old.pte_hi << (ADDR_API_SHFT64 - ADDR_PIDX_SHFT)) >> 28;
if (vsid == VSID_VRMA || vsid == 0 /* Older VRMA */)
continue;
if (old.pte_hi & LPTE_VALID)
phyp_hcall(H_REMOVE, 0, idx, 0);
}
/*
* Scan the large page size property for PAPR compatible machines.
* See PAPR D.5 Changes to Section 5.1.4, 'CPU Node Properties'
* for the encoding of the property.
*/
len = OF_getproplen(node, "ibm,segment-page-sizes");
if (len > 0) {
/*
* We have to use a variable length array on the stack
* since we have very limited stack space.
*/
pcell_t arr[len/sizeof(cell_t)];
res = OF_getencprop(node, "ibm,segment-page-sizes", arr,
sizeof(arr));
len /= 4;
idx = 0;
while (len > 0) {
shift = arr[idx];
slb_encoding = arr[idx + 1];
nptlp = arr[idx + 2];
idx += 3;
len -= 3;
while (len > 0 && nptlp) {
lp_size = arr[idx];
lp_encoding = arr[idx+1];
if (slb_encoding == SLBV_L && lp_encoding == 0)
break;
idx += 2;
len -= 2;
nptlp--;
}
if (nptlp && slb_encoding == SLBV_L && lp_encoding == 0)
break;
}
if (len == 0)
panic("Standard large pages (SLB[L] = 1, PTE[LP] = 0) "
"not supported by this system. Please enable huge "
"page backing if running under PowerKVM.");
moea64_large_page_shift = shift;
moea64_large_page_size = 1ULL << lp_size;
}
moea64_mid_bootstrap(mmup, kernelstart, kernelend);
moea64_late_bootstrap(mmup, kernelstart, kernelend);
/* Test for broken versions of KVM that don't conform to the spec */
if (phyp_hcall(H_CLEAR_MOD, 0, 0) == H_FUNCTION)
brokenkvm = 1;
}
static void
mphyp_cpu_bootstrap(mmu_t mmup, int ap)
{
struct slb *slb = PCPU_GET(aim.slb);
register_t seg0;
int i;
/*
* Install kernel SLB entries
*/
__asm __volatile ("slbia");
__asm __volatile ("slbmfee %0,%1; slbie %0;" : "=r"(seg0) : "r"(0));
for (i = 0; i < 64; i++) {
if (!(slb[i].slbe & SLBE_VALID))
continue;
__asm __volatile ("slbmte %0, %1" ::
"r"(slb[i].slbv), "r"(slb[i].slbe));
}
}
static int64_t
mphyp_pte_synch(mmu_t mmu, struct pvo_entry *pvo)
{
struct lpte pte;
uint64_t junk;
__asm __volatile("ptesync");
phyp_pft_hcall(H_READ, 0, pvo->pvo_pte.slot, 0, 0, &pte.pte_hi,
&pte.pte_lo, &junk);
if ((pte.pte_hi & LPTE_AVPN_MASK) !=
((pvo->pvo_vpn >> (ADDR_API_SHFT64 - ADDR_PIDX_SHFT)) &
LPTE_AVPN_MASK))
return (-1);
if (!(pte.pte_hi & LPTE_VALID))
return (-1);
return (pte.pte_lo & (LPTE_CHG | LPTE_REF));
}
static int64_t
mphyp_pte_clear(mmu_t mmu, struct pvo_entry *pvo, uint64_t ptebit)
{
struct rm_priotracker track;
int64_t refchg;
uint64_t ptelo, junk;
int err;
/*
* This involves two steps (synch and clear) so we need the entry
* not to change in the middle. We are protected against deliberate
* unset by virtue of holding the pmap lock. Protection against
* incidental unset (page table eviction) comes from holding the
* shared eviction lock.
*/
PMAP_LOCK_ASSERT(pvo->pvo_pmap, MA_OWNED);
rm_rlock(&mphyp_eviction_lock, &track);
refchg = mphyp_pte_synch(mmu, pvo);
if (refchg < 0) {
rm_runlock(&mphyp_eviction_lock, &track);
return (refchg);
}
if (brokenkvm) {
/*
* No way to clear either bit, which is total madness.
* Pessimistically claim that, once modified, it stays so
* forever and that it is never referenced.
*/
rm_runlock(&mphyp_eviction_lock, &track);
return (refchg & ~LPTE_REF);
}
if (ptebit & LPTE_CHG) {
err = phyp_pft_hcall(H_CLEAR_MOD, 0, pvo->pvo_pte.slot, 0, 0,
&ptelo, &junk, &junk);
KASSERT(err == H_SUCCESS,
("Error clearing page change bit: %d", err));
refchg |= (ptelo & LPTE_CHG);
}
if (ptebit & LPTE_REF) {
err = phyp_pft_hcall(H_CLEAR_REF, 0, pvo->pvo_pte.slot, 0, 0,
&ptelo, &junk, &junk);
KASSERT(err == H_SUCCESS,
("Error clearing page reference bit: %d", err));
refchg |= (ptelo & LPTE_REF);
}
rm_runlock(&mphyp_eviction_lock, &track);
return (refchg);
}
static int64_t
mphyp_pte_unset(mmu_t mmu, struct pvo_entry *pvo)
{
struct lpte pte;
uint64_t junk;
int err;
PMAP_LOCK_ASSERT(pvo->pvo_pmap, MA_OWNED);
moea64_pte_from_pvo(pvo, &pte);
err = phyp_pft_hcall(H_REMOVE, H_AVPN, pvo->pvo_pte.slot,
pte.pte_hi & LPTE_AVPN_MASK, 0, &pte.pte_hi, &pte.pte_lo,
&junk);
KASSERT(err == H_SUCCESS || err == H_NOT_FOUND,
("Error removing page: %d", err));
if (err == H_NOT_FOUND) {
moea64_pte_overflow--;
return (-1);
}
return (pte.pte_lo & (LPTE_REF | LPTE_CHG));
}
static uintptr_t
mphyp_pte_spillable_ident(uintptr_t ptegbase, struct lpte *to_evict)
{
uint64_t slot, junk, k;
struct lpte pt;
int i, j;
/* Start at a random slot */
i = mftb() % 8;
k = -1;
for (j = 0; j < 8; j++) {
slot = ptegbase + (i + j) % 8;
phyp_pft_hcall(H_READ, 0, slot, 0, 0, &pt.pte_hi,
&pt.pte_lo, &junk);
if (pt.pte_hi & LPTE_WIRED)
continue;
/* This is a candidate, so remember it */
k = slot;
/* Try to get a page that has not been used lately */
if (!(pt.pte_hi & LPTE_VALID) || !(pt.pte_lo & LPTE_REF)) {
memcpy(to_evict, &pt, sizeof(struct lpte));
return (k);
}
}
if (k == -1)
return (k);
phyp_pft_hcall(H_READ, 0, k, 0, 0, &to_evict->pte_hi,
&to_evict->pte_lo, &junk);
return (k);
}
static int
mphyp_pte_insert(mmu_t mmu, struct pvo_entry *pvo)
{
struct rm_priotracker track;
int64_t result;
struct lpte evicted, pte;
uint64_t index, junk, lastptelo;
PMAP_LOCK_ASSERT(pvo->pvo_pmap, MA_OWNED);
/* Initialize PTE */
moea64_pte_from_pvo(pvo, &pte);
evicted.pte_hi = 0;
/* Make sure further insertion is locked out during evictions */
rm_rlock(&mphyp_eviction_lock, &track);
/*
* First try primary hash.
*/
pvo->pvo_pte.slot &= ~7UL; /* Base slot address */
result = phyp_pft_hcall(H_ENTER, 0, pvo->pvo_pte.slot, pte.pte_hi,
pte.pte_lo, &index, &evicted.pte_lo, &junk);
if (result == H_SUCCESS) {
rm_runlock(&mphyp_eviction_lock, &track);
pvo->pvo_pte.slot = index;
return (0);
}
KASSERT(result == H_PTEG_FULL, ("Page insertion error: %ld "
"(ptegidx: %#zx/%#lx, PTE %#lx/%#lx", result, pvo->pvo_pte.slot,
moea64_pteg_count, pte.pte_hi, pte.pte_lo));
/*
* Next try secondary hash.
*/
pvo->pvo_vaddr ^= PVO_HID;
pte.pte_hi ^= LPTE_HID;
pvo->pvo_pte.slot ^= (moea64_pteg_mask << 3);
result = phyp_pft_hcall(H_ENTER, 0, pvo->pvo_pte.slot,
pte.pte_hi, pte.pte_lo, &index, &evicted.pte_lo, &junk);
if (result == H_SUCCESS) {
rm_runlock(&mphyp_eviction_lock, &track);
pvo->pvo_pte.slot = index;
return (0);
}
KASSERT(result == H_PTEG_FULL, ("Secondary page insertion error: %ld",
result));
/*
* Out of luck. Find a PTE to sacrifice.
*/
/* Lock out all insertions for a bit */
rm_runlock(&mphyp_eviction_lock, &track);
rm_wlock(&mphyp_eviction_lock);
index = mphyp_pte_spillable_ident(pvo->pvo_pte.slot, &evicted);
if (index == -1L) {
/* Try other hash table? */
pvo->pvo_vaddr ^= PVO_HID;
pte.pte_hi ^= LPTE_HID;
pvo->pvo_pte.slot ^= (moea64_pteg_mask << 3);
index = mphyp_pte_spillable_ident(pvo->pvo_pte.slot, &evicted);
}
if (index == -1L) {
/* No freeable slots in either PTEG? We're hosed. */
rm_wunlock(&mphyp_eviction_lock);
panic("mphyp_pte_insert: overflow");
return (-1);
}
/* Victim acquired: update page before waving goodbye */
if (evicted.pte_hi & LPTE_VALID) {
result = phyp_pft_hcall(H_REMOVE, H_AVPN, index,
evicted.pte_hi & LPTE_AVPN_MASK, 0, &junk, &lastptelo,
&junk);
moea64_pte_overflow++;
KASSERT(result == H_SUCCESS,
("Error evicting page: %d", (int)result));
}
/*
* Set the new PTE.
*/
result = phyp_pft_hcall(H_ENTER, H_EXACT, index, pte.pte_hi,
pte.pte_lo, &index, &evicted.pte_lo, &junk);
rm_wunlock(&mphyp_eviction_lock); /* All clear */
pvo->pvo_pte.slot = index;
if (result == H_SUCCESS)
return (0);
panic("Page replacement error: %ld", result);
return (result);
}