freebsd-dev/sys/dev/cpuctl/cpuctl.c
2020-09-01 22:11:22 +00:00

605 lines
15 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2006-2008 Stanislav Sedov <stas@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("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/ioccom.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/sched.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/uio.h>
#include <sys/pcpu.h>
#include <sys/smp.h>
#include <sys/pmckern.h>
#include <sys/cpuctl.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <machine/cpufunc.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
#include <x86/ucode.h>
static d_open_t cpuctl_open;
static d_ioctl_t cpuctl_ioctl;
#define CPUCTL_VERSION 1
#ifdef CPUCTL_DEBUG
# define DPRINTF(format,...) printf(format, __VA_ARGS__);
#else
# define DPRINTF(...)
#endif
#define UCODE_SIZE_MAX (4 * 1024 * 1024)
static int cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd,
struct thread *td);
static int cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data,
struct thread *td);
static int cpuctl_do_cpuid_count(int cpu, cpuctl_cpuid_count_args_t *data,
struct thread *td);
static int cpuctl_do_eval_cpu_features(int cpu, struct thread *td);
static int cpuctl_do_update(int cpu, cpuctl_update_args_t *data,
struct thread *td);
static int update_intel(int cpu, cpuctl_update_args_t *args,
struct thread *td);
static int update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td);
static int update_via(int cpu, cpuctl_update_args_t *args,
struct thread *td);
static struct cdev **cpuctl_devs;
static MALLOC_DEFINE(M_CPUCTL, "cpuctl", "CPUCTL buffer");
static struct cdevsw cpuctl_cdevsw = {
.d_version = D_VERSION,
.d_open = cpuctl_open,
.d_ioctl = cpuctl_ioctl,
.d_name = "cpuctl",
};
/*
* This function checks if specified cpu enabled or not.
*/
static int
cpu_enabled(int cpu)
{
return (pmc_cpu_is_disabled(cpu) == 0);
}
/*
* Check if the current thread is bound to a specific cpu.
*/
static int
cpu_sched_is_bound(struct thread *td)
{
int ret;
thread_lock(td);
ret = sched_is_bound(td);
thread_unlock(td);
return (ret);
}
/*
* Switch to target cpu to run.
*/
static void
set_cpu(int cpu, struct thread *td)
{
KASSERT(cpu >= 0 && cpu <= mp_maxid && cpu_enabled(cpu),
("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
thread_lock(td);
sched_bind(td, cpu);
thread_unlock(td);
KASSERT(td->td_oncpu == cpu,
("[cpuctl,%d]: cannot bind to target cpu %d on cpu %d", __LINE__,
cpu, td->td_oncpu));
}
static void
restore_cpu(int oldcpu, int is_bound, struct thread *td)
{
KASSERT(oldcpu >= 0 && oldcpu <= mp_maxid && cpu_enabled(oldcpu),
("[cpuctl,%d]: bad cpu number %d", __LINE__, oldcpu));
thread_lock(td);
if (is_bound == 0)
sched_unbind(td);
else
sched_bind(td, oldcpu);
thread_unlock(td);
}
int
cpuctl_ioctl(struct cdev *dev, u_long cmd, caddr_t data,
int flags, struct thread *td)
{
int cpu, ret;
cpu = dev2unit(dev);
if (cpu > mp_maxid || !cpu_enabled(cpu)) {
DPRINTF("[cpuctl,%d]: bad cpu number %d\n", __LINE__, cpu);
return (ENXIO);
}
/* Require write flag for "write" requests. */
if ((cmd == CPUCTL_MSRCBIT || cmd == CPUCTL_MSRSBIT ||
cmd == CPUCTL_UPDATE || cmd == CPUCTL_WRMSR ||
cmd == CPUCTL_EVAL_CPU_FEATURES) &&
(flags & FWRITE) == 0)
return (EPERM);
switch (cmd) {
case CPUCTL_RDMSR:
ret = cpuctl_do_msr(cpu, (cpuctl_msr_args_t *)data, cmd, td);
break;
case CPUCTL_MSRSBIT:
case CPUCTL_MSRCBIT:
case CPUCTL_WRMSR:
ret = priv_check(td, PRIV_CPUCTL_WRMSR);
if (ret != 0)
goto fail;
ret = cpuctl_do_msr(cpu, (cpuctl_msr_args_t *)data, cmd, td);
break;
case CPUCTL_CPUID:
ret = cpuctl_do_cpuid(cpu, (cpuctl_cpuid_args_t *)data, td);
break;
case CPUCTL_UPDATE:
ret = priv_check(td, PRIV_CPUCTL_UPDATE);
if (ret != 0)
goto fail;
ret = cpuctl_do_update(cpu, (cpuctl_update_args_t *)data, td);
break;
case CPUCTL_CPUID_COUNT:
ret = cpuctl_do_cpuid_count(cpu,
(cpuctl_cpuid_count_args_t *)data, td);
break;
case CPUCTL_EVAL_CPU_FEATURES:
ret = cpuctl_do_eval_cpu_features(cpu, td);
break;
default:
ret = EINVAL;
break;
}
fail:
return (ret);
}
/*
* Actually perform cpuid operation.
*/
static int
cpuctl_do_cpuid_count(int cpu, cpuctl_cpuid_count_args_t *data,
struct thread *td)
{
int is_bound = 0;
int oldcpu;
KASSERT(cpu >= 0 && cpu <= mp_maxid,
("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
/* Explicitly clear cpuid data to avoid returning stale info. */
bzero(data->data, sizeof(data->data));
DPRINTF("[cpuctl,%d]: retrieving cpuid lev %#0x type %#0x for %d cpu\n",
__LINE__, data->level, data->level_type, cpu);
#ifdef __i386__
if (cpu_id == 0)
return (ENODEV);
#endif
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
cpuid_count(data->level, data->level_type, data->data);
restore_cpu(oldcpu, is_bound, td);
return (0);
}
static int
cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data, struct thread *td)
{
cpuctl_cpuid_count_args_t cdata;
int error;
cdata.level = data->level;
/* Override the level type. */
cdata.level_type = 0;
error = cpuctl_do_cpuid_count(cpu, &cdata, td);
bcopy(cdata.data, data->data, sizeof(data->data)); /* Ignore error */
return (error);
}
/*
* Actually perform MSR operations.
*/
static int
cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd, struct thread *td)
{
uint64_t reg;
int is_bound = 0;
int oldcpu;
int ret;
KASSERT(cpu >= 0 && cpu <= mp_maxid,
("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
/*
* Explicitly clear cpuid data to avoid returning stale
* info
*/
DPRINTF("[cpuctl,%d]: operating on MSR %#0x for %d cpu\n", __LINE__,
data->msr, cpu);
#ifdef __i386__
if ((cpu_feature & CPUID_MSR) == 0)
return (ENODEV);
#endif
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
if (cmd == CPUCTL_RDMSR) {
data->data = 0;
ret = rdmsr_safe(data->msr, &data->data);
} else if (cmd == CPUCTL_WRMSR) {
ret = wrmsr_safe(data->msr, data->data);
} else if (cmd == CPUCTL_MSRSBIT) {
critical_enter();
ret = rdmsr_safe(data->msr, &reg);
if (ret == 0)
ret = wrmsr_safe(data->msr, reg | data->data);
critical_exit();
} else if (cmd == CPUCTL_MSRCBIT) {
critical_enter();
ret = rdmsr_safe(data->msr, &reg);
if (ret == 0)
ret = wrmsr_safe(data->msr, reg & ~data->data);
critical_exit();
} else
panic("[cpuctl,%d]: unknown operation requested: %lu",
__LINE__, cmd);
restore_cpu(oldcpu, is_bound, td);
return (ret);
}
/*
* Actually perform microcode update.
*/
static int
cpuctl_do_update(int cpu, cpuctl_update_args_t *data, struct thread *td)
{
cpuctl_cpuid_args_t args = {
.level = 0,
};
char vendor[13];
int ret;
KASSERT(cpu >= 0 && cpu <= mp_maxid,
("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
DPRINTF("[cpuctl,%d]: XXX %d", __LINE__, cpu);
ret = cpuctl_do_cpuid(cpu, &args, td);
if (ret != 0)
return (ret);
((uint32_t *)vendor)[0] = args.data[1];
((uint32_t *)vendor)[1] = args.data[3];
((uint32_t *)vendor)[2] = args.data[2];
vendor[12] = '\0';
if (strncmp(vendor, INTEL_VENDOR_ID, sizeof(INTEL_VENDOR_ID)) == 0)
ret = update_intel(cpu, data, td);
else if(strncmp(vendor, AMD_VENDOR_ID, sizeof(AMD_VENDOR_ID)) == 0)
ret = update_amd(cpu, data, td);
else if(strncmp(vendor, CENTAUR_VENDOR_ID, sizeof(CENTAUR_VENDOR_ID))
== 0)
ret = update_via(cpu, data, td);
else
ret = ENXIO;
return (ret);
}
struct ucode_update_data {
void *ptr;
int cpu;
int ret;
};
static void
ucode_intel_load_rv(void *arg)
{
struct ucode_update_data *d;
d = arg;
if (PCPU_GET(cpuid) == d->cpu)
d->ret = ucode_intel_load(d->ptr, true, NULL, NULL);
}
static int
update_intel(int cpu, cpuctl_update_args_t *args, struct thread *td)
{
struct ucode_update_data d;
void *ptr;
int is_bound, oldcpu, ret;
if (args->size == 0 || args->data == NULL) {
DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__);
return (EINVAL);
}
if (args->size > UCODE_SIZE_MAX) {
DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__);
return (EINVAL);
}
/*
* 16 byte alignment required. Rely on the fact that
* malloc(9) always returns the pointer aligned at least on
* the size of the allocation.
*/
ptr = malloc(args->size + 16, M_CPUCTL, M_WAITOK);
if (copyin(args->data, ptr, args->size) != 0) {
DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed",
__LINE__, args->data, ptr, args->size);
ret = EFAULT;
goto out;
}
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
d.ptr = ptr;
d.cpu = cpu;
smp_rendezvous(NULL, ucode_intel_load_rv, NULL, &d);
restore_cpu(oldcpu, is_bound, td);
ret = d.ret;
/*
* Replace any existing update. This ensures that the new update
* will be reloaded automatically during ACPI resume.
*/
if (ret == 0)
ptr = ucode_update(ptr);
out:
free(ptr, M_CPUCTL);
return (ret);
}
/*
* NB: MSR 0xc0010020, MSR_K8_UCODE_UPDATE, is not documented by AMD.
* Coreboot, illumos and Linux source code was used to understand
* its workings.
*/
static void
amd_ucode_wrmsr(void *ucode_ptr)
{
uint32_t tmp[4];
wrmsr_safe(MSR_K8_UCODE_UPDATE, (uintptr_t)ucode_ptr);
do_cpuid(0, tmp);
}
static int
update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td)
{
void *ptr;
int ret;
if (args->size == 0 || args->data == NULL) {
DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__);
return (EINVAL);
}
if (args->size > UCODE_SIZE_MAX) {
DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__);
return (EINVAL);
}
/*
* 16 byte alignment required. Rely on the fact that
* malloc(9) always returns the pointer aligned at least on
* the size of the allocation.
*/
ptr = malloc(args->size + 16, M_CPUCTL, M_ZERO | M_WAITOK);
if (copyin(args->data, ptr, args->size) != 0) {
DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed",
__LINE__, args->data, ptr, args->size);
ret = EFAULT;
goto fail;
}
smp_rendezvous(NULL, amd_ucode_wrmsr, NULL, ptr);
ret = 0;
fail:
free(ptr, M_CPUCTL);
return (ret);
}
static int
update_via(int cpu, cpuctl_update_args_t *args, struct thread *td)
{
void *ptr;
uint64_t rev0, rev1, res;
uint32_t tmp[4];
int is_bound;
int oldcpu;
int ret;
if (args->size == 0 || args->data == NULL) {
DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__);
return (EINVAL);
}
if (args->size > UCODE_SIZE_MAX) {
DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__);
return (EINVAL);
}
/*
* 4 byte alignment required.
*/
ptr = malloc(args->size, M_CPUCTL, M_WAITOK);
if (copyin(args->data, ptr, args->size) != 0) {
DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed",
__LINE__, args->data, ptr, args->size);
ret = EFAULT;
goto fail;
}
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
critical_enter();
rdmsr_safe(MSR_BIOS_SIGN, &rev0); /* Get current microcode revision. */
/*
* Perform update.
*/
wrmsr_safe(MSR_BIOS_UPDT_TRIG, (uintptr_t)(ptr));
do_cpuid(1, tmp);
/*
* Result are in low byte of MSR FCR5:
* 0x00: No update has been attempted since RESET.
* 0x01: The last attempted update was successful.
* 0x02: The last attempted update was unsuccessful due to a bad
* environment. No update was loaded and any preexisting
* patches are still active.
* 0x03: The last attempted update was not applicable to this processor.
* No update was loaded and any preexisting patches are still
* active.
* 0x04: The last attempted update was not successful due to an invalid
* update data block. No update was loaded and any preexisting
* patches are still active
*/
rdmsr_safe(0x1205, &res);
res &= 0xff;
critical_exit();
rdmsr_safe(MSR_BIOS_SIGN, &rev1); /* Get new microcode revision. */
restore_cpu(oldcpu, is_bound, td);
DPRINTF("[cpu,%d]: rev0=%x rev1=%x res=%x\n", __LINE__,
(unsigned)(rev0 >> 32), (unsigned)(rev1 >> 32), (unsigned)res);
if (res != 0x01)
ret = EINVAL;
else
ret = 0;
fail:
free(ptr, M_CPUCTL);
return (ret);
}
static int
cpuctl_do_eval_cpu_features(int cpu, struct thread *td)
{
int is_bound = 0;
int oldcpu;
KASSERT(cpu >= 0 && cpu <= mp_maxid,
("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
#ifdef __i386__
if (cpu_id == 0)
return (ENODEV);
#endif
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
identify_cpu1();
identify_cpu2();
restore_cpu(oldcpu, is_bound, td);
hw_ibrs_recalculate(true);
hw_ssb_recalculate(true);
#ifdef __amd64__
amd64_syscall_ret_flush_l1d_recalc();
pmap_allow_2m_x_ept_recalculate();
#endif
hw_mds_recalculate();
x86_taa_recalculate();
x86_rngds_mitg_recalculate(true);
printcpuinfo();
return (0);
}
int
cpuctl_open(struct cdev *dev, int flags, int fmt __unused, struct thread *td)
{
int ret = 0;
int cpu;
cpu = dev2unit(dev);
if (cpu > mp_maxid || !cpu_enabled(cpu)) {
DPRINTF("[cpuctl,%d]: incorrect cpu number %d\n", __LINE__,
cpu);
return (ENXIO);
}
if (flags & FWRITE)
ret = securelevel_gt(td->td_ucred, 0);
return (ret);
}
static int
cpuctl_modevent(module_t mod __unused, int type, void *data __unused)
{
int cpu;
switch(type) {
case MOD_LOAD:
if (bootverbose)
printf("cpuctl: access to MSR registers/cpuid info.\n");
cpuctl_devs = malloc(sizeof(*cpuctl_devs) * (mp_maxid + 1), M_CPUCTL,
M_WAITOK | M_ZERO);
CPU_FOREACH(cpu)
if (cpu_enabled(cpu))
cpuctl_devs[cpu] = make_dev(&cpuctl_cdevsw, cpu,
UID_ROOT, GID_KMEM, 0640, "cpuctl%d", cpu);
break;
case MOD_UNLOAD:
CPU_FOREACH(cpu) {
if (cpuctl_devs[cpu] != NULL)
destroy_dev(cpuctl_devs[cpu]);
}
free(cpuctl_devs, M_CPUCTL);
break;
case MOD_SHUTDOWN:
break;
default:
return (EOPNOTSUPP);
}
return (0);
}
DEV_MODULE(cpuctl, cpuctl_modevent, NULL);
MODULE_VERSION(cpuctl, CPUCTL_VERSION);