* Copyright (c) 2000 The NetBSD Foundation, Inc.

/* $NetBSD: cpu.c,v 1.145 2023/02/25 00:35:01 riastradh Exp $ */

/*-
* Copyright (c) 2000 The NetBSD Foundation, Inc.
* Copyright (c) 2002, 2006, 2007 YAMAMOTO Takashi,
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by RedBack Networks Inc.
*
* Author: Bill Sommerfeld
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/

/*
* Copyright (c) 1999 Stefan Grefen
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY 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 AND 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>
__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.145 2023/02/25 00:35:01 riastradh Exp $");

#include "opt_ddb.h"
#include "opt_multiprocessor.h"
#include "opt_mpbios.h" /* for MPDEBUG */
#include "opt_mtrr.h"
#include "opt_xen.h"

#include "lapic.h"
#include "ioapic.h"

#include <sys/param.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/kmem.h>
#include <sys/cpu.h>
#include <sys/cpufreq.h>
#include <sys/atomic.h>
#include <sys/reboot.h>
#include <sys/idle.h>

#include <uvm/uvm.h>

#include <machine/cpu.h>
#include <machine/cpufunc.h>
#include <machine/cpuvar.h>
#include <machine/pmap.h>
#include <machine/pmap_private.h>
#include <machine/vmparam.h>
#include <machine/mpbiosvar.h>
#include <machine/pcb.h>
#include <machine/specialreg.h>
#include <machine/segments.h>
#include <machine/gdt.h>
#include <machine/mtrr.h>
#include <machine/pio.h>

#include <x86/fpu.h>

#include <xen/xen.h>
#include <xen/include/public/vcpu.h>
#include <xen/vcpuvar.h>

#if NLAPIC > 0
#include <machine/apicvar.h>
#include <machine/i82489reg.h>
#include <machine/i82489var.h>
#endif

#include <dev/ic/mc146818reg.h>
#include <dev/isa/isareg.h>

static int cpu_match(device_t, cfdata_t, void *);
static void cpu_attach(device_t, device_t, void *);
static void cpu_defer(device_t);
static int cpu_rescan(device_t, const char *, const int *);
static void cpu_childdetached(device_t, device_t);
static int vcpu_match(device_t, cfdata_t, void *);
static void vcpu_attach(device_t, device_t, void *);
static void cpu_attach_common(device_t, device_t, void *);
void cpu_offline_md(void);

struct cpu_softc {
device_t sc_dev; /* device tree glue */
struct cpu_info *sc_info; /* pointer to CPU info */
bool sc_wasonline;
};

int mp_cpu_start(struct cpu_info *, vaddr_t);
void mp_cpu_start_cleanup(struct cpu_info *);
const struct cpu_functions mp_cpu_funcs = { mp_cpu_start, NULL,
mp_cpu_start_cleanup };

CFATTACH_DECL2_NEW(cpu, sizeof(struct cpu_softc),
cpu_match, cpu_attach, NULL, NULL, cpu_rescan, cpu_childdetached);

CFATTACH_DECL_NEW(vcpu, sizeof(struct cpu_softc),
vcpu_match, vcpu_attach, NULL, NULL);

/*
* Statically-allocated CPU info for the primary CPU (or the only
* CPU, on uniprocessors). The CPU info list is initialized to
* point at it.
*/
struct cpu_info cpu_info_primary __aligned(CACHE_LINE_SIZE) = {
.ci_dev = 0,
.ci_self = &cpu_info_primary,
.ci_idepth = -1,
.ci_curlwp = &lwp0,
.ci_curldt = -1,
};
struct cpu_info phycpu_info_primary __aligned(CACHE_LINE_SIZE) = {
.ci_dev = 0,
.ci_self = &phycpu_info_primary,
};

struct cpu_info *cpu_info_list = &cpu_info_primary;
struct cpu_info *phycpu_info_list = &phycpu_info_primary;

uint32_t cpu_feature[7] __read_mostly; /* X86 CPUID feature bits
* [0] basic features %edx
* [1] basic features %ecx
* [2] extended features %edx
* [3] extended features %ecx
* [4] VIA padlock features
* [5] structured extended features cpuid.7:%ebx
* [6] structured extended features cpuid.7:%ecx
*/

bool x86_mp_online;
paddr_t mp_trampoline_paddr = MP_TRAMPOLINE;

#if defined(MULTIPROCESSOR)
void cpu_hatch(void *);
static void cpu_boot_secondary(struct cpu_info *ci);
static void cpu_start_secondary(struct cpu_info *ci);
#endif /* MULTIPROCESSOR */

static int
cpu_match(device_t parent, cfdata_t match, void *aux)
{

return 1;
}

static void
cpu_attach(device_t parent, device_t self, void *aux)
{
struct cpu_softc *sc = device_private(self);
struct cpu_attach_args *caa = aux;
struct cpu_info *ci;
uintptr_t ptr;
static int nphycpu = 0;

sc->sc_dev = self;

/*
* If we're an Application Processor, allocate a cpu_info
* If we're the first attached CPU use the primary cpu_info,
* otherwise allocate a new one
*/
aprint_naive("\n");
aprint_normal("\n");
if (nphycpu > 0) {
struct cpu_info *tmp;
ptr = (uintptr_t)kmem_zalloc(sizeof(*ci) + CACHE_LINE_SIZE - 1,
KM_SLEEP);
ci = (struct cpu_info *)roundup2(ptr, CACHE_LINE_SIZE);
ci->ci_curldt = -1;

tmp = phycpu_info_list;
while (tmp->ci_next)
tmp = tmp->ci_next;

tmp->ci_next = ci;
} else {
ci = &phycpu_info_primary;
}

ci->ci_self = ci;
sc->sc_info = ci;

ci->ci_dev = self;
ci->ci_acpiid = caa->cpu_id;
ci->ci_cpuid = caa->cpu_number;
ci->ci_vcpu = NULL;
ci->ci_index = nphycpu++;
ci->ci_kfpu_spl = -1;

if (!pmf_device_register(self, NULL, NULL))
aprint_error_dev(self, "couldn't establish power handler\n");

(void)config_defer(self, cpu_defer);
}

static void
cpu_defer(device_t self)
{
cpu_rescan(self, NULL, NULL);
}

static int
cpu_rescan(device_t self, const char *ifattr, const int *locators)
{
struct cpu_softc *sc = device_private(self);
struct cpufeature_attach_args cfaa;
struct cpu_info *ci = sc->sc_info;

memset(&cfaa, 0, sizeof(cfaa));
cfaa.ci = ci;

if (ifattr_match(ifattr, "cpufeaturebus")) {

if (ci->ci_frequency == NULL) {
cfaa.name = "frequency";
ci->ci_frequency =
config_found(self, &cfaa, NULL,
CFARGS(.iattr = "cpufeaturebus"));
}
}

return 0;
}

static void
cpu_childdetached(device_t self, device_t child)
{
struct cpu_softc *sc = device_private(self);
struct cpu_info *ci = sc->sc_info;

if (ci->ci_frequency == child)
ci->ci_frequency = NULL;
}

static int
vcpu_match(device_t parent, cfdata_t match, void *aux)
{
struct vcpu_attach_args *vcaa = aux;
struct vcpu_runstate_info vcr;
int error;

if (strcmp(vcaa->vcaa_name, match->cf_name) == 0) {
error = HYPERVISOR_vcpu_op(VCPUOP_get_runstate_info,
vcaa->vcaa_caa.cpu_number, &vcr);
switch (error) {
case 0:
return 1;
case -ENOENT:
return 0;
default:
panic("Unknown hypervisor error %d returned on vcpu runstate probe\n", error);
}
}

return 0;
}

static void
vcpu_attach(device_t parent, device_t self, void *aux)
{
struct vcpu_attach_args *vcaa = aux;

KASSERT(vcaa->vcaa_caa.cpu_func == NULL);
vcaa->vcaa_caa.cpu_func = &mp_cpu_funcs;
cpu_attach_common(parent, self, &vcaa->vcaa_caa);

if (!pmf_device_register(self, NULL, NULL))
aprint_error_dev(self, "couldn't establish power handler\n");
}

static int
vcpu_is_up(struct cpu_info *ci)
{
KASSERT(ci != NULL);
return HYPERVISOR_vcpu_op(VCPUOP_is_up, ci->ci_vcpuid, NULL);
}

static void
cpu_vm_init(struct cpu_info *ci)
{
int ncolors = 2, i;

for (i = CAI_ICACHE; i <= CAI_L2CACHE; i++) {
struct x86_cache_info *cai;
int tcolors;

cai = &ci->ci_cinfo[i];

tcolors = atop(cai->cai_totalsize);
switch (cai->cai_associativity) {
case 0xff:
tcolors = 1; /* fully associative */
break;
case 0:
case 1:
break;
default:
tcolors /= cai->cai_associativity;
}
ncolors = uimax(ncolors, tcolors);
}

/*
* Knowing the size of the largest cache on this CPU, potentially
* re-color our pages.
*/
aprint_debug_dev(ci->ci_dev, "%d page colors\n", ncolors);
uvm_page_recolor(ncolors);
pmap_tlb_cpu_init(ci);
#ifndef __HAVE_DIRECT_MAP
pmap_vpage_cpu_init(ci);
#endif
}

static void
cpu_attach_common(device_t parent, device_t self, void *aux)
{
struct cpu_softc *sc = device_private(self);
struct cpu_attach_args *caa = aux;
struct cpu_info *ci;
uintptr_t ptr;
int cpunum = caa->cpu_number;
static bool again = false;

sc->sc_dev = self;

/*
* If we're an Application Processor, allocate a cpu_info
* structure, otherwise use the primary's.
*/
if (caa->cpu_role == CPU_ROLE_AP) {
aprint_naive(": Application Processor\n");
ptr = (uintptr_t)kmem_alloc(sizeof(*ci) + CACHE_LINE_SIZE - 1,
KM_SLEEP);
ci = (struct cpu_info *)roundup2(ptr, CACHE_LINE_SIZE);
memset(ci, 0, sizeof(*ci));
cpu_init_tss(ci);
} else {
aprint_naive(": %s Processor\n",
caa->cpu_role == CPU_ROLE_SP ? "Single" : "Boot");
ci = &cpu_info_primary;
}

ci->ci_self = ci;
sc->sc_info = ci;
ci->ci_dev = self;
ci->ci_cpuid = cpunum;
ci->ci_vcpuid = cpunum;
ci->ci_kfpu_spl = -1;

KASSERT(HYPERVISOR_shared_info != NULL);
KASSERT(cpunum < XEN_LEGACY_MAX_VCPUS);
ci->ci_vcpu = &HYPERVISOR_shared_info->vcpu_info[cpunum];

KASSERT(ci->ci_func == 0);
ci->ci_func = caa->cpu_func;
aprint_normal("\n");

/* Must be called before mi_cpu_attach(). */
cpu_vm_init(ci);

if (caa->cpu_role == CPU_ROLE_AP) {
int error;

error = mi_cpu_attach(ci);

KASSERT(ci->ci_data.cpu_idlelwp != NULL);
if (error != 0) {
aprint_error_dev(self,
"mi_cpu_attach failed with %d\n", error);
return;
}

} else {
KASSERT(ci->ci_data.cpu_idlelwp != NULL);
}

KASSERT(ci->ci_cpuid == ci->ci_index);
#ifdef __x86_64__
/* No user PGD mapped for this CPU yet */
ci->ci_xen_current_user_pgd = 0;
#endif
mutex_init(&ci->ci_kpm_mtx, MUTEX_DEFAULT, IPL_VM);
pmap_reference(pmap_kernel());
ci->ci_pmap = pmap_kernel();
ci->ci_tlbstate = TLBSTATE_STALE;

/*
* Boot processor may not be attached first, but the below
* must be done to allow booting other processors.
*/
if (!again) {
atomic_or_32(&ci->ci_flags, CPUF_PRESENT | CPUF_PRIMARY);
/* Basic init. */
cpu_intr_init(ci);
cpu_get_tsc_freq(ci);
cpu_init(ci);
pmap_cpu_init_late(ci);

/* Every processor needs to init its own ipi h/w (similar to lapic) */
xen_ipi_init();

/* Make sure DELAY() is initialized. */
DELAY(1);
again = true;
}

/* further PCB init done later. */

switch (caa->cpu_role) {
case CPU_ROLE_SP:
atomic_or_32(&ci->ci_flags, CPUF_SP);
cpu_identify(ci);
x86_cpu_idle_init();
break;

case CPU_ROLE_BP:
atomic_or_32(&ci->ci_flags, CPUF_BSP);
cpu_identify(ci);
x86_cpu_idle_init();
break;

case CPU_ROLE_AP:
atomic_or_32(&ci->ci_flags, CPUF_AP);

/*
* report on an AP
*/

#if defined(MULTIPROCESSOR)
/* interrupt handler stack */
cpu_intr_init(ci);

/* Setup per-cpu memory for idt */
idt_vec_init_cpu_md(&ci->ci_idtvec, cpu_index(ci));

/* Setup per-cpu memory for gdt */
gdt_alloc_cpu(ci);

pmap_cpu_init_late(ci);
cpu_start_secondary(ci);

if (ci->ci_flags & CPUF_PRESENT) {
struct cpu_info *tmp;

cpu_identify(ci);
tmp = cpu_info_list;
while (tmp->ci_next)
tmp = tmp->ci_next;

tmp->ci_next = ci;
}
#else
aprint_error_dev(ci->ci_dev, "not started\n");
#endif
break;

default:
panic("unknown processor type??\n");
}

#ifdef MPVERBOSE
if (mp_verbose) {
struct lwp *l = ci->ci_data.cpu_idlelwp;
struct pcb *pcb = lwp_getpcb(l);

aprint_verbose_dev(self,
"idle lwp at %p, idle sp at %p\n",
l,
#ifdef i386
(void *)pcb->pcb_esp
#else
(void *)pcb->pcb_rsp
#endif
);

}
#endif /* MPVERBOSE */
}

/*
* Initialize the processor appropriately.
*/

void
cpu_init(struct cpu_info *ci)
{
uint32_t cr4 = 0;

/*
* If we have FXSAVE/FXRESTOR, use them.
*/
if (cpu_feature[0] & CPUID_FXSR) {
cr4 |= CR4_OSFXSR;

/*
* If we have SSE/SSE2, enable XMM exceptions.
*/
if (cpu_feature[0] & (CPUID_SSE|CPUID_SSE2))
cr4 |= CR4_OSXMMEXCPT;
}

/* If xsave is supported, enable it */
if (cpu_feature[1] & CPUID2_XSAVE && x86_fpu_save >= FPU_SAVE_XSAVE)
cr4 |= CR4_OSXSAVE;

if (cr4) {
cr4 |= rcr4();
lcr4(cr4);
}

if (x86_fpu_save >= FPU_SAVE_FXSAVE) {
fpuinit_mxcsr_mask();
}

/*
* Changing CR4 register may change cpuid values. For example, setting
* CR4_OSXSAVE sets CPUID2_OSXSAVE. The CPUID2_OSXSAVE is in
* ci_feat_val[1], so update it.
* XXX Other than ci_feat_val[1] might be changed.
*/
if (cpuid_level >= 1) {
u_int descs[4];

x86_cpuid(1, descs);
ci->ci_feat_val[1] = descs[2];
}

/* If xsave is enabled, enable all fpu features */
if (cr4 & CR4_OSXSAVE) {
wrxcr(0, x86_xsave_features & XCR0_FPU);
}

atomic_or_32(&ci->ci_flags, CPUF_RUNNING);
}

#ifdef MULTIPROCESSOR

void
cpu_boot_secondary_processors(void)
{
struct cpu_info *ci;
kcpuset_t *cpus;
u_long i;

kcpuset_create(&cpus, true);
kcpuset_set(cpus, cpu_index(curcpu()));
for (i = 0; i < maxcpus; i++) {
ci = cpu_lookup(i);
if (ci == NULL)
continue;
if (ci->ci_data.cpu_idlelwp == NULL)
continue;
if ((ci->ci_flags & CPUF_PRESENT) == 0)
continue;
if (ci->ci_flags & (CPUF_BSP|CPUF_SP|CPUF_PRIMARY))
continue;
cpu_boot_secondary(ci);
kcpuset_set(cpus, cpu_index(ci));
}
while (!kcpuset_match(cpus, kcpuset_running))
;
kcpuset_destroy(cpus);

x86_mp_online = true;
}

static void
cpu_init_idle_lwp(struct cpu_info *ci)
{
struct lwp *l = ci->ci_data.cpu_idlelwp;
struct pcb *pcb = lwp_getpcb(l);

pcb->pcb_cr0 = rcr0();
}

void
cpu_init_idle_lwps(void)
{
struct cpu_info *ci;
u_long i;

for (i = 0; i < maxcpus; i++) {
ci = cpu_lookup(i);
if (ci == NULL)
continue;
if (ci->ci_data.cpu_idlelwp == NULL)
continue;
if ((ci->ci_flags & CPUF_PRESENT) == 0)
continue;
cpu_init_idle_lwp(ci);
}
}

static void
cpu_start_secondary(struct cpu_info *ci)
{
int i;

aprint_debug_dev(ci->ci_dev, "starting\n");

ci->ci_curlwp = ci->ci_data.cpu_idlelwp;

if (CPU_STARTUP(ci, (vaddr_t) cpu_hatch) != 0) {
return;
}

/*
* wait for it to become ready
*/
for (i = 100000; (!(ci->ci_flags & CPUF_PRESENT)) && i > 0; i--) {
delay(10);
}
if ((ci->ci_flags & CPUF_PRESENT) == 0) {
aprint_error_dev(ci->ci_dev, "failed to become ready\n");
#if defined(MPDEBUG) && defined(DDB)
printf("dropping into debugger; continue from here to resume boot\n");
Debugger();
#endif
}

CPU_START_CLEANUP(ci);
}

void
cpu_boot_secondary(struct cpu_info *ci)
{
int i;
atomic_or_32(&ci->ci_flags, CPUF_GO);
for (i = 100000; (!(ci->ci_flags & CPUF_RUNNING)) && i > 0; i--) {
delay(10);
}
if ((ci->ci_flags & CPUF_RUNNING) == 0) {
aprint_error_dev(ci->ci_dev, "CPU failed to start\n");
#if defined(MPDEBUG) && defined(DDB)
printf("dropping into debugger; continue from here to resume boot\n");
Debugger();
#endif
}
}

/*
* APs end up here immediately after initialisation and VCPUOP_up in
* mp_cpu_start().
* At this point, we are running in the idle pcb/idle stack of the new
* CPU. This function jumps to the idle loop and starts looking for
* work.
*/
extern void x86_64_tls_switch(struct lwp *);
void
cpu_hatch(void *v)
{
struct cpu_info *ci = (struct cpu_info *)v;
struct pcb *pcb;
int s, i;

/* Setup TLS and kernel GS/FS */
cpu_init_msrs(ci, true);
cpu_init_idt(ci);
gdt_init_cpu(ci);

cpu_probe(ci);

atomic_or_32(&ci->ci_flags, CPUF_PRESENT);

while ((ci->ci_flags & CPUF_GO) == 0) {
/* Don't use delay, boot CPU may be patching the text. */
for (i = 10000; i != 0; i--)
x86_pause();
}

/* Because the text may have been patched in x86_patch(). */
x86_flush();
tlbflushg();

KASSERT((ci->ci_flags & CPUF_RUNNING) == 0);

KASSERT(ci->ci_curlwp == ci->ci_data.cpu_idlelwp);
KASSERT(curlwp == ci->ci_data.cpu_idlelwp);
pcb = lwp_getpcb(curlwp);
pcb->pcb_cr3 = pmap_pdirpa(pmap_kernel(), 0);

xen_ipi_init();

xen_initclocks();

#ifdef __x86_64__
fpuinit(ci);
#endif

lldt(GSEL(GLDT_SEL, SEL_KPL));

cpu_init(ci);
cpu_get_tsc_freq(ci);

s = splhigh();
x86_enable_intr();
splx(s);

aprint_debug_dev(ci->ci_dev, "running\n");

KASSERT(ci->ci_curlwp == ci->ci_data.cpu_idlelwp);
idle_loop(NULL);
KASSERT(false);
}

#if defined(DDB)

#include <ddb/db_output.h>
#include <machine/db_machdep.h>

/*
* Dump CPU information from ddb.
*/
void
cpu_debug_dump(void)
{
struct cpu_info *ci;
CPU_INFO_ITERATOR cii;

db_printf("addr dev id flags ipis curlwp\n");
for (CPU_INFO_FOREACH(cii, ci)) {
db_printf("%p %s %ld %x %x %10p\n",
ci,
ci->ci_dev == NULL ? "BOOT" : device_xname(ci->ci_dev),
(long)ci->ci_vcpuid,
ci->ci_flags, ci->ci_ipis,
ci->ci_curlwp);
}
}
#endif /* DDB */

#endif /* MULTIPROCESSOR */

extern void hypervisor_callback(void);
extern void failsafe_callback(void);
#ifdef __x86_64__
typedef void (vector)(void);
extern vector Xsyscall, Xsyscall32;
#endif

/*
* Setup the "trampoline". On Xen, we setup nearly all cpu context
* outside a trampoline, so we prototype and call targetip like so:
* void targetip(struct cpu_info *);
*/

static void
gdt_prepframes(paddr_t *frames, vaddr_t base, uint32_t entries)
{
int i;
for (i = 0; i < entries; i++) {
frames[i] = ((paddr_t)xpmap_ptetomach(
(pt_entry_t *)(base + (i << PAGE_SHIFT)))) >> PAGE_SHIFT;

/* Mark Read-only */
pmap_pte_clearbits(kvtopte(base + (i << PAGE_SHIFT)),
PTE_W);
}
}

#ifdef __x86_64__
extern char *ldtstore;

static void
xen_init_amd64_vcpuctxt(struct cpu_info *ci, struct vcpu_guest_context *initctx,
void targetrip(struct cpu_info *))
{
/* page frames to point at GDT */
extern int gdt_size;
paddr_t frames[16];
psize_t gdt_ents;

struct lwp *l;
struct pcb *pcb;

volatile struct vcpu_info *vci;

KASSERT(ci != NULL);
KASSERT(ci != &cpu_info_primary);
KASSERT(initctx != NULL);
KASSERT(targetrip != NULL);

memset(initctx, 0, sizeof(*initctx));

gdt_ents = roundup(gdt_size, PAGE_SIZE) >> PAGE_SHIFT;
KASSERT(gdt_ents <= 16);

gdt_prepframes(frames, (vaddr_t)ci->ci_gdt, gdt_ents);

/* Initialise the vcpu context: We use idle_loop()'s pcb context. */

l = ci->ci_data.cpu_idlelwp;

KASSERT(l != NULL);
pcb = lwp_getpcb(l);
KASSERT(pcb != NULL);

/* resume with interrupts off */
vci = ci->ci_vcpu;
vci->evtchn_upcall_mask = 1;
__insn_barrier();

/* resume in kernel-mode */
initctx->flags = VGCF_in_kernel | VGCF_online;

/* Stack and entry points:
* We arrange for the stack frame for cpu_hatch() to
* appear as a callee frame of lwp_trampoline(). Being a
* leaf frame prevents trampling on any of the MD stack setup
* that x86/vm_machdep.c:cpu_lwp_fork() does for idle_loop()
*/

initctx->user_regs.rdi = (uint64_t) ci; /* targetrip(ci); */
initctx->user_regs.rip = (vaddr_t) targetrip;

initctx->user_regs.cs = GSEL(GCODE_SEL, SEL_KPL);

initctx->user_regs.rflags = pcb->pcb_flags;
initctx->user_regs.rsp = pcb->pcb_rsp;

/* Data segments */
initctx->user_regs.ss = GSEL(GDATA_SEL, SEL_KPL);
initctx->user_regs.es = GSEL(GDATA_SEL, SEL_KPL);
initctx->user_regs.ds = GSEL(GDATA_SEL, SEL_KPL);

/* GDT */
memcpy(initctx->gdt_frames, frames, sizeof(frames));
initctx->gdt_ents = gdt_ents;

/* LDT */
initctx->ldt_base = (unsigned long)ldtstore;
initctx->ldt_ents = LDT_SIZE >> 3;

/* Kernel context state */
initctx->kernel_ss = GSEL(GDATA_SEL, SEL_KPL);
initctx->kernel_sp = pcb->pcb_rsp0;
initctx->ctrlreg[0] = pcb->pcb_cr0;
initctx->ctrlreg[1] = 0; /* "resuming" from kernel - no User cr3. */
initctx->ctrlreg[2] = (vaddr_t)targetrip;
/*
* Use pmap_kernel() L4 PD directly, until we setup the
* per-cpu L4 PD in pmap_cpu_init_late()
*/
initctx->ctrlreg[3] = xen_pfn_to_cr3(x86_btop(xpmap_ptom(ci->ci_kpm_pdirpa)));
initctx->ctrlreg[4] = CR4_PAE | CR4_OSFXSR | CR4_OSXMMEXCPT;

/* Xen callbacks */
initctx->event_callback_eip = (unsigned long)hypervisor_callback;
initctx->failsafe_callback_eip = (unsigned long)failsafe_callback;
initctx->syscall_callback_eip = (unsigned long)Xsyscall;

return;
}
#else /* i386 */
extern union descriptor *ldtstore;
extern void Xsyscall(void);

static void
xen_init_i386_vcpuctxt(struct cpu_info *ci, struct vcpu_guest_context *initctx,
void targeteip(struct cpu_info *))
{
/* page frames to point at GDT */
extern int gdt_size;
paddr_t frames[16];
psize_t gdt_ents;

struct lwp *l;
struct pcb *pcb;

volatile struct vcpu_info *vci;

KASSERT(ci != NULL);
KASSERT(ci != &cpu_info_primary);
KASSERT(initctx != NULL);
KASSERT(targeteip != NULL);

memset(initctx, 0, sizeof(*initctx));

gdt_ents = roundup(gdt_size, PAGE_SIZE) >> PAGE_SHIFT;
KASSERT(gdt_ents <= 16);

gdt_prepframes(frames, (vaddr_t)ci->ci_gdt, gdt_ents);

/*
* Initialise the vcpu context:
* We use this cpu's idle_loop() pcb context.
*/

l = ci->ci_data.cpu_idlelwp;

KASSERT(l != NULL);
pcb = lwp_getpcb(l);
KASSERT(pcb != NULL);

/* resume with interrupts off */
vci = ci->ci_vcpu;
vci->evtchn_upcall_mask = 1;
__insn_barrier();

/* resume in kernel-mode */
initctx->flags = VGCF_in_kernel | VGCF_online;

/* Stack frame setup for cpu_hatch():
* We arrange for the stack frame for cpu_hatch() to
* appear as a callee frame of lwp_trampoline(). Being a
* leaf frame prevents trampling on any of the MD stack setup
* that x86/vm_machdep.c:cpu_lwp_fork() does for idle_loop()
*/

initctx->user_regs.esp = pcb->pcb_esp - 4; /* Leave word for
arg1 */
{
/* targeteip(ci); */
uint32_t *arg = (uint32_t *)initctx->user_regs.esp;
arg[1] = (uint32_t)ci; /* arg1 */
}

initctx->user_regs.eip = (vaddr_t)targeteip;
initctx->user_regs.cs = GSEL(GCODE_SEL, SEL_KPL);
initctx->user_regs.eflags |= pcb->pcb_iopl;

/* Data segments */
initctx->user_regs.ss = GSEL(GDATA_SEL, SEL_KPL);
initctx->user_regs.es = GSEL(GDATA_SEL, SEL_KPL);
initctx->user_regs.ds = GSEL(GDATA_SEL, SEL_KPL);
initctx->user_regs.fs = GSEL(GDATA_SEL, SEL_KPL);

/* GDT */
memcpy(initctx->gdt_frames, frames, sizeof(frames));
initctx->gdt_ents = gdt_ents;

/* LDT */
initctx->ldt_base = (unsigned long)ldtstore;
initctx->ldt_ents = NLDT;

/* Kernel context state */
initctx->kernel_ss = GSEL(GDATA_SEL, SEL_KPL);
initctx->kernel_sp = pcb->pcb_esp0;
initctx->ctrlreg[0] = pcb->pcb_cr0;
initctx->ctrlreg[1] = 0; /* "resuming" from kernel - no User cr3. */
initctx->ctrlreg[2] = (vaddr_t)targeteip;
initctx->ctrlreg[3] = xen_pfn_to_cr3(x86_btop(xpmap_ptom(ci->ci_pae_l3_pdirpa)));
initctx->ctrlreg[4] = /* CR4_PAE | */CR4_OSFXSR | CR4_OSXMMEXCPT;

/* Xen callbacks */
initctx->event_callback_eip = (unsigned long)hypervisor_callback;
initctx->event_callback_cs = GSEL(GCODE_SEL, SEL_KPL);
initctx->failsafe_callback_eip = (unsigned long)failsafe_callback;
initctx->failsafe_callback_cs = GSEL(GCODE_SEL, SEL_KPL);

return;
}
#endif /* __x86_64__ */

int
mp_cpu_start(struct cpu_info *ci, vaddr_t target)
{
int hyperror;
struct vcpu_guest_context *vcpuctx;

KASSERT(ci != NULL);
KASSERT(ci != &cpu_info_primary);
KASSERT(ci->ci_flags & CPUF_AP);

vcpuctx = kmem_alloc(sizeof(*vcpuctx), KM_SLEEP);

#ifdef __x86_64__
xen_init_amd64_vcpuctxt(ci, vcpuctx, (void (*)(struct cpu_info *))target);
#else
xen_init_i386_vcpuctxt(ci, vcpuctx, (void (*)(struct cpu_info *))target);
#endif

/* Initialise the given vcpu to execute cpu_hatch(ci); */
if ((hyperror = HYPERVISOR_vcpu_op(VCPUOP_initialise, ci->ci_vcpuid, vcpuctx))) {
aprint_error(": context initialisation failed. errno = %d\n", hyperror);
goto out;
}

/* Start it up */

/* First bring it down */
if ((hyperror = HYPERVISOR_vcpu_op(VCPUOP_down, ci->ci_vcpuid, NULL))) {
aprint_error(": VCPUOP_down hypervisor command failed. errno = %d\n", hyperror);
goto out;
}

if ((hyperror = HYPERVISOR_vcpu_op(VCPUOP_up, ci->ci_vcpuid, NULL))) {
aprint_error(": VCPUOP_up hypervisor command failed. errno = %d\n", hyperror);
goto out;
}

if (!vcpu_is_up(ci)) {
aprint_error(": did not come up\n");
hyperror = -1;
goto out;
}

out:
kmem_free(vcpuctx, sizeof(*vcpuctx));
return hyperror;
}

void
mp_cpu_start_cleanup(struct cpu_info *ci)
{
if (vcpu_is_up(ci)) {
aprint_debug_dev(ci->ci_dev, "is started.\n");
} else {
aprint_error_dev(ci->ci_dev, "did not start up.\n");
}
}

void
cpu_init_msrs(struct cpu_info *ci, bool full)
{
#ifdef __x86_64__
if (full) {
HYPERVISOR_set_segment_base(SEGBASE_FS, 0);
HYPERVISOR_set_segment_base(SEGBASE_GS_KERNEL, (uint64_t)ci);
HYPERVISOR_set_segment_base(SEGBASE_GS_USER, 0);
}
#endif

if (cpu_feature[2] & CPUID_NOX)
wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_NXE);
}

void
cpu_offline_md(void)
{
return;
}

void
cpu_get_tsc_freq(struct cpu_info *ci)
{
uint32_t vcpu_tversion;
const volatile vcpu_time_info_t *tinfo = &ci->ci_vcpu->time;

vcpu_tversion = tinfo->version;
while (tinfo->version == vcpu_tversion); /* Wait for a time update. XXX: timeout ? */

uint64_t freq = 1000000000ULL << 32;
freq = freq / (uint64_t)tinfo->tsc_to_system_mul;
if (tinfo->tsc_shift < 0)
freq = freq << -tinfo->tsc_shift;
else
freq = freq >> tinfo->tsc_shift;
ci->ci_data.cpu_cc_freq = freq;
}

/*
* Loads pmap for the current CPU.
*/
void
cpu_load_pmap(struct pmap *pmap, struct pmap *oldpmap)
{
struct cpu_info *ci = curcpu();
cpuid_t cid = cpu_index(ci);
int i;

KASSERT(kpreempt_disabled());
KASSERT(pmap != pmap_kernel());

mutex_enter(&ci->ci_kpm_mtx);
/* make new pmap visible to xen_kpm_sync() */
kcpuset_atomic_set(pmap->pm_xen_ptp_cpus, cid);

#ifdef __x86_64__
pd_entry_t *new_pgd;
paddr_t l4_pd_ma;

l4_pd_ma = xpmap_ptom_masked(ci->ci_kpm_pdirpa);

/*
* Map user space address in kernel space and load
* user cr3
*/
new_pgd = pmap->pm_pdir;
KASSERT(pmap == ci->ci_pmap);

/* Copy user pmap L4 PDEs (in user addr. range) to per-cpu L4 */
for (i = 0; i < PDIR_SLOT_USERLIM; i++) {
KASSERT(pmap != pmap_kernel() || new_pgd[i] == 0);
if (ci->ci_kpm_pdir[i] != new_pgd[i]) {
xpq_queue_pte_update(l4_pd_ma + i * sizeof(pd_entry_t),
new_pgd[i]);
}
}

xen_set_user_pgd(pmap_pdirpa(pmap, 0));
ci->ci_xen_current_user_pgd = pmap_pdirpa(pmap, 0);
#else
paddr_t l3_pd = xpmap_ptom_masked(ci->ci_pae_l3_pdirpa);
/* don't update the kernel L3 slot */
for (i = 0; i < PDP_SIZE - 1; i++) {
xpq_queue_pte_update(l3_pd + i * sizeof(pd_entry_t),
xpmap_ptom(pmap->pm_pdirpa[i]) | PTE_P);
}
#endif

tlbflush();

/* old pmap no longer visible to xen_kpm_sync() */
if (oldpmap != pmap_kernel()) {
kcpuset_atomic_clear(oldpmap->pm_xen_ptp_cpus, cid);
}
mutex_exit(&ci->ci_kpm_mtx);
}

/*
* pmap_cpu_init_late: perform late per-CPU initialization.
*
* Short note about percpu PDIR pages. Both the PAE and __x86_64__ architectures
* have per-cpu PDIR tables, for two different reasons:
* - on PAE, this is to get around Xen's pagetable setup constraints (multiple
* L3[3]s cannot point to the same L2 - Xen will refuse to pin a table set up
* this way).
* - on __x86_64__, this is for multiple CPUs to map in different user pmaps
* (see cpu_load_pmap()).
*
* What this means for us is that the PDIR of the pmap_kernel() is considered
* to be a canonical "SHADOW" PDIR with the following properties:
* - its recursive mapping points to itself
* - per-cpu recursive mappings point to themselves on __x86_64__
* - per-cpu L4 pages' kernel entries are expected to be in sync with
* the shadow
*/

void
pmap_cpu_init_late(struct cpu_info *ci)
{
int i;

/*
* The BP has already its own PD page allocated during early
* MD startup.
*/

#ifdef __x86_64__
/* Setup per-cpu normal_pdes */
extern pd_entry_t * const normal_pdes[];
for (i = 0;i < PTP_LEVELS - 1;i++) {
ci->ci_normal_pdes[i] = normal_pdes[i];
}
#endif

if (ci == &cpu_info_primary)
return;

KASSERT(ci != NULL);

#if defined(i386)
cpu_alloc_l3_page(ci);
KASSERT(ci->ci_pae_l3_pdirpa != 0);

/* Initialise L2 entries 0 - 2: Point them to pmap_kernel() */
for (i = 0; i < PDP_SIZE - 1; i++) {
ci->ci_pae_l3_pdir[i] =
xpmap_ptom_masked(pmap_kernel()->pm_pdirpa[i]) | PTE_P;
}
#endif

ci->ci_kpm_pdir = (pd_entry_t *)uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
UVM_KMF_WIRED | UVM_KMF_ZERO | UVM_KMF_NOWAIT);

if (ci->ci_kpm_pdir == NULL) {
panic("%s: failed to allocate L4 per-cpu PD for CPU %d\n",
__func__, cpu_index(ci));
}
ci->ci_kpm_pdirpa = vtophys((vaddr_t)ci->ci_kpm_pdir);
KASSERT(ci->ci_kpm_pdirpa != 0);

#ifdef __x86_64__
extern pt_entry_t xpmap_pg_nx;

/* Copy over the pmap_kernel() shadow L4 entries */
memcpy(ci->ci_kpm_pdir, pmap_kernel()->pm_pdir, PAGE_SIZE);

/* Recursive kernel mapping */
ci->ci_kpm_pdir[PDIR_SLOT_PTE] = xpmap_ptom_masked(ci->ci_kpm_pdirpa)
| PTE_P | xpmap_pg_nx;
#else
/* Copy over the pmap_kernel() shadow L2 entries */
memcpy(ci->ci_kpm_pdir, pmap_kernel()->pm_pdir + PDIR_SLOT_KERN,
nkptp[PTP_LEVELS - 1] * sizeof(pd_entry_t));
#endif

/* Xen wants a RO pdir. */
pmap_protect(pmap_kernel(), (vaddr_t)ci->ci_kpm_pdir,
(vaddr_t)ci->ci_kpm_pdir + PAGE_SIZE, VM_PROT_READ);
pmap_update(pmap_kernel());

#ifdef __x86_64__
xpq_queue_pin_l4_table(xpmap_ptom_masked(ci->ci_kpm_pdirpa));
#else
/*
* Initialize L3 entry 3. This mapping is shared across all pmaps and is
* static, ie: loading a new pmap will not update this entry.
*/
ci->ci_pae_l3_pdir[3] = xpmap_ptom_masked(ci->ci_kpm_pdirpa) | PTE_P;

/* Xen wants a RO L3. */
pmap_protect(pmap_kernel(), (vaddr_t)ci->ci_pae_l3_pdir,
(vaddr_t)ci->ci_pae_l3_pdir + PAGE_SIZE, VM_PROT_READ);
pmap_update(pmap_kernel());

xpq_queue_pin_l3_table(xpmap_ptom_masked(ci->ci_pae_l3_pdirpa));
#endif
}

/*
* Notify all other cpus to halt.
*/

void
cpu_broadcast_halt(void)
{
xen_broadcast_ipi(XEN_IPI_HALT);
}

/*
* Send a dummy ipi to a cpu, and raise an AST on the running LWP.
*/

void
cpu_kick(struct cpu_info *ci)
{
(void)xen_send_ipi(ci, XEN_IPI_AST);
}