/*
* text_poke_early - Update instructions on a live kernel at boot time
* @addr: address to modify
* @opcode: source of the copy
* @len: length to copy
*
* When you use this code to patch more than one byte of an instruction
* you need to make sure that other CPUs cannot execute this code in parallel.
* Also no thread must be currently preempted in the middle of these
* instructions. And on the local CPU you need to be protected again NMI or MCE
* handlers seeing an inconsistent instruction while you patch.
*
* This routine is called with local interrupt disabled.
*/
static void *__init text_poke_early(void *addr, const void *opcode, size_t len)
{
memcpy(addr, opcode, len);
sync_core();
return addr;
}
static force_inline void do_vgettimeofday(struct timeval * tv)
{
long sequence, t;
unsigned long sec, usec;
do {
sequence = __vxtime_sequence[1];
rmb();
sec = __xtime.tv_sec;
usec = __xtime.tv_usec + (__jiffies - __wall_jiffies) * (1000000 / HZ);
switch (__vxtime.mode) {
case VXTIME_TSC:
sync_core();
rdtscll(t);
usec += (((t - __vxtime.last_tsc) * __vxtime.tsc_quot) >> 32);
break;
case VXTIME_HPET:
usec += ((readl(fix_to_virt(VSYSCALL_HPET) + 0xf0) - __vxtime.last) * __vxtime.quot) >> 32;
break;
}
rmb();
} while (sequence != __vxtime_sequence[0]);
tv->tv_sec = sec + usec / 1000000;
tv->tv_usec = usec % 1000000;
}
/*
* Mark it noinline so we make sure it is not unrolled.
* Wait until value is reached.
*/
static noinline void tsc_barrier(long wait_cpu, int value)
{
sync_core();
per_cpu(wait_sync, smp_processor_id())--;
do {
barrier();
} while (unlikely(per_cpu(wait_sync, wait_cpu) > value));
__get_cpu_var(tsc_count) = get_cycles_sync();
}
int cch_allocate(struct gru_context_configuration_handle *cch)
{
int ret;
cch->opc = CCHOP_ALLOCATE;
start_instruction(cch);
ret = wait_instruction_complete(cch, cchop_allocate);
/*
* Stop speculation into the GSEG being mapped by the previous ALLOCATE.
* The GSEG memory does not exist until the ALLOCATE completes.
*/
sync_core();
return ret;
}
int cch_deallocate(struct gru_context_configuration_handle *cch)
{
int ret;
cch->opc = CCHOP_DEALLOCATE;
start_instruction(cch);
ret = wait_instruction_complete(cch, cchop_deallocate);
/*
* Stop speculation into the GSEG being unmapped by the previous
* DEALLOCATE.
*/
sync_core();
return ret;
}
int cch_allocate(struct gru_context_configuration_handle *cch)
{
int ret;
cch->opc = CCHOP_ALLOCATE;
start_instruction(cch);
ret = wait_instruction_complete(cch, cchop_allocate);
/*
*/
sync_core();
return ret;
}
/*----------------------------------------------------------------------*/
int gru_get_cb_exception_detail(void *cb,
struct control_block_extended_exc_detail *excdet)
{
struct gru_control_block_extended *cbe;
struct gru_thread_state *kgts = NULL;
unsigned long off;
int cbrnum, bid;
/*
* Locate kgts for cb. This algorithm is SLOW but
* this function is rarely called (ie., almost never).
* Performance does not matter.
*/
for_each_possible_blade(bid) {
if (!gru_base[bid])
break;
kgts = gru_base[bid]->bs_kgts;
if (!kgts || !kgts->ts_gru)
continue;
off = cb - kgts->ts_gru->gs_gru_base_vaddr;
if (off < GRU_SIZE)
break;
kgts = NULL;
}
BUG_ON(!kgts);
cbrnum = thread_cbr_number(kgts, get_cb_number(cb));
cbe = get_cbe(GRUBASE(cb), cbrnum);
gru_flush_cache(cbe); /* CBE not coherent */
sync_core();
excdet->opc = cbe->opccpy;
excdet->exopc = cbe->exopccpy;
excdet->ecause = cbe->ecause;
excdet->exceptdet0 = cbe->idef1upd;
excdet->exceptdet1 = cbe->idef3upd;
gru_flush_cache(cbe);
return 0;
}
int gru_get_cb_exception_detail(void *cb,
struct control_block_extended_exc_detail *excdet)
{
struct gru_control_block_extended *cbe;
struct gru_thread_state *kgts = NULL;
unsigned long off;
int cbrnum, bid;
/*
*/
for_each_possible_blade(bid) {
if (!gru_base[bid])
break;
kgts = gru_base[bid]->bs_kgts;
if (!kgts || !kgts->ts_gru)
continue;
off = cb - kgts->ts_gru->gs_gru_base_vaddr;
if (off < GRU_SIZE)
break;
kgts = NULL;
}
BUG_ON(!kgts);
cbrnum = thread_cbr_number(kgts, get_cb_number(cb));
cbe = get_cbe(GRUBASE(cb), cbrnum);
gru_flush_cache(cbe); /* */
sync_core();
excdet->opc = cbe->opccpy;
excdet->exopc = cbe->exopccpy;
excdet->ecause = cbe->ecause;
excdet->exceptdet0 = cbe->idef1upd;
excdet->exceptdet1 = cbe->idef3upd;
gru_flush_cache(cbe);
return 0;
}
static void __init synchronize_tsc_ap (void)
{
int i;
/*
* Not every cpu is online at the time
* this gets called, so we first wait for the BP to
* finish SMP initialization:
*/
while (!atomic_read(&tsc_start_flag)) mb();
for (i = 0; i < NR_LOOPS; i++) {
atomic_inc(&tsc_count_start);
while (atomic_read(&tsc_count_start) != num_booting_cpus()) mb();
sync_core();
rdtscll(tsc_values[smp_processor_id()]);
if (i == NR_LOOPS-1)
write_tsc(0, 0);
atomic_inc(&tsc_count_stop);
while (atomic_read(&tsc_count_stop) != num_booting_cpus()) mb();
}
}
static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
{
u64 misc_enable;
/* Unmask CPUID levels if masked: */
if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
if (misc_enable & MSR_IA32_MISC_ENABLE_LIMIT_CPUID) {
misc_enable &= ~MSR_IA32_MISC_ENABLE_LIMIT_CPUID;
wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
c->cpuid_level = cpuid_eax(0);
get_cpu_cap(c);
}
}
if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
(c->x86 == 0x6 && c->x86_model >= 0x0e))
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
if (c->x86 >= 6 && !cpu_has(c, X86_FEATURE_IA64)) {
unsigned lower_word;
wrmsr(MSR_IA32_UCODE_REV, 0, 0);
/* Required by the SDM */
sync_core();
rdmsr(MSR_IA32_UCODE_REV, lower_word, c->microcode);
}
/*
* Atom erratum AAE44/AAF40/AAG38/AAH41:
*
* A race condition between speculative fetches and invalidating
* a large page. This is worked around in microcode, but we
* need the microcode to have already been loaded... so if it is
* not, recommend a BIOS update and disable large pages.
*/
if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_mask <= 2 &&
c->microcode < 0x20e) {
printk(KERN_WARNING "Atom PSE erratum detected, BIOS microcode update recommended\n");
clear_cpu_cap(c, X86_FEATURE_PSE);
}
#ifdef CONFIG_X86_64
set_cpu_cap(c, X86_FEATURE_SYSENTER32);
#else
/* Netburst reports 64 bytes clflush size, but does IO in 128 bytes */
if (c->x86 == 15 && c->x86_cache_alignment == 64)
c->x86_cache_alignment = 128;
#endif
/* CPUID workaround for 0F33/0F34 CPU */
if (c->x86 == 0xF && c->x86_model == 0x3
&& (c->x86_mask == 0x3 || c->x86_mask == 0x4))
c->x86_phys_bits = 36;
/*
* c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
* with P/T states and does not stop in deep C-states.
*
* It is also reliable across cores and sockets. (but not across
* cabinets - we turn it off in that case explicitly.)
*/
if (c->x86_power & (1 << 8)) {
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
if (!check_tsc_unstable())
sched_clock_stable = 1;
}
/*
* There is a known erratum on Pentium III and Core Solo
* and Core Duo CPUs.
* " Page with PAT set to WC while associated MTRR is UC
* may consolidate to UC "
* Because of this erratum, it is better to stick with
* setting WC in MTRR rather than using PAT on these CPUs.
*
* Enable PAT WC only on P4, Core 2 or later CPUs.
*/
if (c->x86 == 6 && c->x86_model < 15)
clear_cpu_cap(c, X86_FEATURE_PAT);
#ifdef CONFIG_KMEMCHECK
/*
* P4s have a "fast strings" feature which causes single-
* stepping REP instructions to only generate a #DB on
* cache-line boundaries.
*
* Ingo Molnar reported a Pentium D (model 6) and a Xeon
* (model 2) with the same problem.
*/
if (c->x86 == 15) {
rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
if (misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING) {
printk(KERN_INFO "kmemcheck: Disabling fast string operations\n");
misc_enable &= ~MSR_IA32_MISC_ENABLE_FAST_STRING;
wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
}
}
#endif
/*
* If fast string is not enabled in IA32_MISC_ENABLE for any reason,
* clear the fast string and enhanced fast string CPU capabilities.
*/
if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
if (!(misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING)) {
printk(KERN_INFO "Disabled fast string operations\n");
setup_clear_cpu_cap(X86_FEATURE_REP_GOOD);
setup_clear_cpu_cap(X86_FEATURE_ERMS);
}
}
}
static void early_init_intel(struct cpuinfo_x86 *c)
{
u64 misc_enable;
/* Unmask CPUID levels if masked: */
if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
if (msr_clear_bit(MSR_IA32_MISC_ENABLE,
MSR_IA32_MISC_ENABLE_LIMIT_CPUID_BIT) > 0) {
c->cpuid_level = cpuid_eax(0);
get_cpu_cap(c);
}
}
if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
(c->x86 == 0x6 && c->x86_model >= 0x0e))
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
if (c->x86 >= 6 && !cpu_has(c, X86_FEATURE_IA64)) {
unsigned lower_word;
wrmsr(MSR_IA32_UCODE_REV, 0, 0);
/* Required by the SDM */
sync_core();
rdmsr(MSR_IA32_UCODE_REV, lower_word, c->microcode);
}
/*
* Atom erratum AAE44/AAF40/AAG38/AAH41:
*
* A race condition between speculative fetches and invalidating
* a large page. This is worked around in microcode, but we
* need the microcode to have already been loaded... so if it is
* not, recommend a BIOS update and disable large pages.
*/
if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_mask <= 2 &&
c->microcode < 0x20e) {
pr_warn("Atom PSE erratum detected, BIOS microcode update recommended\n");
clear_cpu_cap(c, X86_FEATURE_PSE);
}
#ifdef CONFIG_X86_64
set_cpu_cap(c, X86_FEATURE_SYSENTER32);
#else
/* Netburst reports 64 bytes clflush size, but does IO in 128 bytes */
if (c->x86 == 15 && c->x86_cache_alignment == 64)
c->x86_cache_alignment = 128;
#endif
/* CPUID workaround for 0F33/0F34 CPU */
if (c->x86 == 0xF && c->x86_model == 0x3
&& (c->x86_mask == 0x3 || c->x86_mask == 0x4))
c->x86_phys_bits = 36;
/*
* c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
* with P/T states and does not stop in deep C-states.
*
* It is also reliable across cores and sockets. (but not across
* cabinets - we turn it off in that case explicitly.)
*/
if (c->x86_power & (1 << 8)) {
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
if (!check_tsc_unstable())
set_sched_clock_stable();
}
/* Penwell and Cloverview have the TSC which doesn't sleep on S3 */
if (c->x86 == 6) {
switch (c->x86_model) {
case 0x27: /* Penwell */
case 0x35: /* Cloverview */
case 0x4a: /* Merrifield */
set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC_S3);
break;
default:
break;
}
}
/*
* There is a known erratum on Pentium III and Core Solo
* and Core Duo CPUs.
* " Page with PAT set to WC while associated MTRR is UC
* may consolidate to UC "
* Because of this erratum, it is better to stick with
* setting WC in MTRR rather than using PAT on these CPUs.
*
* Enable PAT WC only on P4, Core 2 or later CPUs.
*/
if (c->x86 == 6 && c->x86_model < 15)
clear_cpu_cap(c, X86_FEATURE_PAT);
#ifdef CONFIG_KMEMCHECK
/*
* P4s have a "fast strings" feature which causes single-
* stepping REP instructions to only generate a #DB on
* cache-line boundaries.
*
* Ingo Molnar reported a Pentium D (model 6) and a Xeon
* (model 2) with the same problem.
*/
if (c->x86 == 15)
if (msr_clear_bit(MSR_IA32_MISC_ENABLE,
MSR_IA32_MISC_ENABLE_FAST_STRING_BIT) > 0)
pr_info("kmemcheck: Disabling fast string operations\n");
#endif
/*
* If fast string is not enabled in IA32_MISC_ENABLE for any reason,
* clear the fast string and enhanced fast string CPU capabilities.
*/
if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
if (!(misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING)) {
pr_info("Disabled fast string operations\n");
setup_clear_cpu_cap(X86_FEATURE_REP_GOOD);
setup_clear_cpu_cap(X86_FEATURE_ERMS);
}
}
/*
* Intel Quark Core DevMan_001.pdf section 6.4.11
* "The operating system also is required to invalidate (i.e., flush)
* the TLB when any changes are made to any of the page table entries.
* The operating system must reload CR3 to cause the TLB to be flushed"
*
* As a result, boot_cpu_has(X86_FEATURE_PGE) in arch/x86/include/asm/tlbflush.h
* should be false so that __flush_tlb_all() causes CR3 insted of CR4.PGE
* to be modified.
*/
if (c->x86 == 5 && c->x86_model == 9) {
pr_info("Disabling PGE capability bit\n");
setup_clear_cpu_cap(X86_FEATURE_PGE);
}
if (c->cpuid_level >= 0x00000001) {
u32 eax, ebx, ecx, edx;
cpuid(0x00000001, &eax, &ebx, &ecx, &edx);
/*
* If HTT (EDX[28]) is set EBX[16:23] contain the number of
* apicids which are reserved per package. Store the resulting
* shift value for the package management code.
*/
if (edx & (1U << 28))
c->x86_coreid_bits = get_count_order((ebx >> 16) & 0xff);
}
static void __init synchronize_tsc_bp (void)
{
int i;
unsigned long long t0;
unsigned long long sum, avg;
long long delta;
long one_usec;
int buggy = 0;
printk(KERN_INFO "checking TSC synchronization across %u CPUs: ",num_booting_cpus());
one_usec = cpu_khz;
atomic_set(&tsc_start_flag, 1);
wmb();
/*
* We loop a few times to get a primed instruction cache,
* then the last pass is more or less synchronized and
* the BP and APs set their cycle counters to zero all at
* once. This reduces the chance of having random offsets
* between the processors, and guarantees that the maximum
* delay between the cycle counters is never bigger than
* the latency of information-passing (cachelines) between
* two CPUs.
*/
for (i = 0; i < NR_LOOPS; i++) {
/*
* all APs synchronize but they loop on '== num_cpus'
*/
while (atomic_read(&tsc_count_start) != num_booting_cpus()-1) mb();
atomic_set(&tsc_count_stop, 0);
wmb();
/*
* this lets the APs save their current TSC:
*/
atomic_inc(&tsc_count_start);
sync_core();
rdtscll(tsc_values[smp_processor_id()]);
/*
* We clear the TSC in the last loop:
*/
if (i == NR_LOOPS-1)
write_tsc(0, 0);
/*
* Wait for all APs to leave the synchronization point:
*/
while (atomic_read(&tsc_count_stop) != num_booting_cpus()-1) mb();
atomic_set(&tsc_count_start, 0);
wmb();
atomic_inc(&tsc_count_stop);
}
sum = 0;
for (i = 0; i < NR_CPUS; i++) {
if (cpu_isset(i, cpu_callout_map)) {
t0 = tsc_values[i];
sum += t0;
}
}
avg = sum / num_booting_cpus();
sum = 0;
for (i = 0; i < NR_CPUS; i++) {
if (!cpu_isset(i, cpu_callout_map))
continue;
delta = tsc_values[i] - avg;
if (delta < 0)
delta = -delta;
/*
* We report bigger than 2 microseconds clock differences.
*/
if (delta > 2*one_usec) {
long realdelta;
if (!buggy) {
buggy = 1;
printk("\n");
}
realdelta = delta / one_usec;
if (tsc_values[i] < avg)
realdelta = -realdelta;
printk("BIOS BUG: CPU#%d improperly initialized, has %ld usecs TSC skew! FIXED.\n",
i, realdelta);
}
sum += delta;
}
if (!buggy)
printk("passed.\n");
}
