freebsd-dev/sys/dev/cpuctl/cpuctl.c
Ed Schouten 6bfa9a2d66 Replace all calls to minor() with dev2unit().
After I removed all the unit2minor()/minor2unit() calls from the kernel
yesterday, I realised calling minor() everywhere is quite confusing.
Character devices now only have the ability to store a unit number, not
a minor number. Remove the confusion by using dev2unit() everywhere.

This commit could also be considered as a bug fix. A lot of drivers call
minor(), while they should actually be calling dev2unit(). In -CURRENT
this isn't a problem, but it turns out we never had any problem reports
related to that issue in the past. I suspect not many people connect
more than 256 pieces of the same hardware.

Reviewed by:	kib
2008-09-27 08:51:18 +00:00

446 lines
11 KiB
C

/*-
* 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 <machine/cpufunc.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
static d_open_t cpuctl_open;
static d_ioctl_t cpuctl_ioctl;
#define CPUCTL_VERSION 1
#ifdef DEBUG
# define DPRINTF(format,...) printf(format, __VA_ARGS__);
#else
# define DPRINTF(...)
#endif
#define UCODE_SIZE_MAX (10 * 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_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 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_ncpus && 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", __LINE__, cpu));
}
static void
restore_cpu(int oldcpu, int is_bound, struct thread *td)
{
KASSERT(oldcpu >= 0 && oldcpu < mp_ncpus && 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 ret;
int cpu = dev2unit(dev);
if (cpu >= mp_ncpus || !cpu_enabled(cpu)) {
DPRINTF("[cpuctl,%d]: bad cpu number %d\n", __LINE__, cpu);
return (ENXIO);
}
/* Require write flag for "write" requests. */
if ((cmd == CPUCTL_WRMSR || cmd == CPUCTL_UPDATE) &&
((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_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;
default:
ret = EINVAL;
break;
}
fail:
return (ret);
}
/*
* Actually perform cpuid operation.
*/
static int
cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data, struct thread *td)
{
int is_bound = 0;
int oldcpu;
KASSERT(cpu >= 0 && cpu < mp_ncpus,
("[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]: retriving cpuid level %#0x for %d cpu\n",
__LINE__, data->level, cpu);
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
do_cpuid(data->level, data->data);
restore_cpu(oldcpu, is_bound, td);
return (0);
}
/*
* Actually perform MSR operations.
*/
static int
cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd, struct thread *td)
{
int is_bound = 0;
int oldcpu;
int ret;
KASSERT(cpu >= 0 && cpu < mp_ncpus,
("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
/*
* Explicitly clear cpuid data to avoid returning stale
* info
*/
data->data = 0;
DPRINTF("[cpuctl,%d]: operating on MSR %#0x for %d cpu\n", __LINE__,
data->msr, cpu);
oldcpu = td->td_oncpu;
is_bound = cpu_sched_is_bound(td);
set_cpu(cpu, td);
ret = cmd == CPUCTL_RDMSR ? rdmsr_safe(data->msr, &data->data) :
wrmsr_safe(data->msr, data->data);
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_ncpus,
("[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) {
DPRINTF("[cpuctl,%d]: cannot retrive cpuid info for cpu %d",
__LINE__, cpu);
return (ENXIO);
}
((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, INTEL_VENDOR_ID, sizeof(AMD_VENDOR_ID)) == 0)
ret = update_amd(cpu, data, td);
else
ret = ENXIO;
return (ret);
}
static int
update_intel(int cpu, cpuctl_update_args_t *args, struct thread *td)
{
void *ptr = NULL;
uint64_t rev0, rev1;
uint32_t tmp[4];
int is_bound = 0;
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);
}
/*
* 16 byte alignment required.
*/
ptr = malloc(args->size + 16, M_CPUCTL, M_WAITOK);
ptr = (void *)(16 + ((intptr_t)ptr & ~0xf));
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 micorcode revision. */
/*
* Perform update.
*/
wrmsr_safe(MSR_BIOS_UPDT_TRIG, (uintptr_t)(ptr));
wrmsr_safe(MSR_BIOS_SIGN, 0);
/*
* Serialize instruction flow.
*/
do_cpuid(0, tmp);
critical_exit();
rdmsr_safe(MSR_BIOS_SIGN, &rev1); /* Get new micorcode revision. */
restore_cpu(oldcpu, is_bound, td);
if (rev1 > rev0)
ret = 0;
else
ret = EEXIST;
fail:
if (ptr != NULL)
contigfree(ptr, args->size, M_CPUCTL);
return (ret);
}
static int
update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td)
{
void *ptr = NULL;
uint32_t tmp[4];
int is_bound = 0;
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);
}
/*
* XXX Might not require contignous address space - needs check
*/
ptr = contigmalloc(args->size, M_CPUCTL, 0, 0, 0xffffffff, 16, 0);
if (ptr == NULL) {
DPRINTF("[cpuctl,%d]: cannot allocate %zd bytes of memory",
__LINE__, args->size);
return (ENOMEM);
}
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();
/*
* Perform update.
*/
wrmsr_safe(MSR_K8_UCODE_UPDATE, (uintptr_t)args->data);
/*
* Serialize instruction flow.
*/
do_cpuid(0, tmp);
critical_exit();
restore_cpu(oldcpu, is_bound, td);
ret = 0;
fail:
if (ptr != NULL)
contigfree(ptr, args->size, M_CPUCTL);
return (ret);
}
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_ncpus || !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 ((cpu_feature & CPUID_MSR) == 0) {
if (bootverbose)
printf("cpuctl: not available.\n");
return (ENODEV);
}
if (bootverbose)
printf("cpuctl: access to MSR registers/cpuid info.\n");
cpuctl_devs = (struct cdev **)malloc(sizeof(void *) * mp_ncpus,
M_CPUCTL, M_WAITOK | M_ZERO);
if (cpuctl_devs == NULL) {
DPRINTF("[cpuctl,%d]: cannot allocate memory\n",
__LINE__);
return (ENOMEM);
}
for (cpu = 0; cpu < mp_ncpus; 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:
for (cpu = 0; cpu < mp_ncpus; 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);