smp_64.c
// SPDX-License-Identifier: GPL-2.0
/* smp.c: Sparc64 SMP support.
*
* Copyright (C) 1997, 2007, 2008 David S. Miller (davem@davemloft.net)
*/
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/sched/mm.h>
#include <linux/sched/hotplug.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <linux/threads.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/fs.h>
#include <linux/seq_file.h>
#include <linux/cache.h>
#include <linux/jiffies.h>
#include <linux/profile.h>
#include <linux/memblock.h>
#include <linux/vmalloc.h>
#include <linux/ftrace.h>
#include <linux/cpu.h>
#include <linux/slab.h>
#include <linux/kgdb.h>
#include <asm/head.h>
#include <asm/ptrace.h>
#include <linux/atomic.h>
#include <asm/tlbflush.h>
#include <asm/mmu_context.h>
#include <asm/cpudata.h>
#include <asm/hvtramp.h>
#include <asm/io.h>
#include <asm/timer.h>
#include <asm/setup.h>
#include <asm/irq.h>
#include <asm/irq_regs.h>
#include <asm/page.h>
#include <asm/oplib.h>
#include <linux/uaccess.h>
#include <asm/starfire.h>
#include <asm/tlb.h>
#include <asm/pgalloc.h>
#include <asm/sections.h>
#include <asm/prom.h>
#include <asm/mdesc.h>
#include <asm/ldc.h>
#include <asm/hypervisor.h>
#include <asm/pcr.h>
#include "cpumap.h"
#include "kernel.h"
DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
cpumask_t cpu_core_map[NR_CPUS] __read_mostly =
{ [0 ... NR_CPUS-1] = CPU_MASK_NONE };
cpumask_t cpu_core_sib_map[NR_CPUS] __read_mostly = {
[0 ... NR_CPUS-1] = CPU_MASK_NONE };
cpumask_t cpu_core_sib_cache_map[NR_CPUS] __read_mostly = {
[0 ... NR_CPUS - 1] = CPU_MASK_NONE };
EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
EXPORT_SYMBOL(cpu_core_map);
EXPORT_SYMBOL(cpu_core_sib_map);
EXPORT_SYMBOL(cpu_core_sib_cache_map);
static cpumask_t smp_commenced_mask;
static DEFINE_PER_CPU(bool, poke);
static bool cpu_poke;
void smp_info(struct seq_file *m)
{
int i;
seq_printf(m, "State:\n");
for_each_online_cpu(i)
seq_printf(m, "CPU%d:\t\tonline\n", i);
}
void smp_bogo(struct seq_file *m)
{
int i;
for_each_online_cpu(i)
seq_printf(m,
"Cpu%dClkTck\t: %016lx\n",
i, cpu_data(i).clock_tick);
}
extern void setup_sparc64_timer(void);
static volatile unsigned long callin_flag = 0;
void smp_callin(void)
{
int cpuid = hard_smp_processor_id();
__local_per_cpu_offset = __per_cpu_offset(cpuid);
if (tlb_type == hypervisor)
sun4v_ktsb_register();
__flush_tlb_all();
setup_sparc64_timer();
if (cheetah_pcache_forced_on)
cheetah_enable_pcache();
callin_flag = 1;
__asm__ __volatile__("membar #Sync\n\t"
"flush %%g6" : : : "memory");
/* Clear this or we will die instantly when we
* schedule back to this idler...
*/
current_thread_info()->new_child = 0;
/* Attach to the address space of init_task. */
mmgrab(&init_mm);
current->active_mm = &init_mm;
/* inform the notifiers about the new cpu */
notify_cpu_starting(cpuid);
while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
rmb();
set_cpu_online(cpuid, true);
local_irq_enable();
cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
}
void cpu_panic(void)
{
printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
panic("SMP bolixed\n");
}
/* This tick register synchronization scheme is taken entirely from
* the ia64 port, see arch/ia64/kernel/smpboot.c for details and credit.
*
* The only change I've made is to rework it so that the master
* initiates the synchonization instead of the slave. -DaveM
*/
#define MASTER 0
#define SLAVE (SMP_CACHE_BYTES/sizeof(unsigned long))
#define NUM_ROUNDS 64 /* magic value */
#define NUM_ITERS 5 /* likewise */
static DEFINE_RAW_SPINLOCK(itc_sync_lock);
static unsigned long go[SLAVE + 1];
#define DEBUG_TICK_SYNC 0
static inline long get_delta (long *rt, long *master)
{
unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
unsigned long tcenter, t0, t1, tm;
unsigned long i;
for (i = 0; i < NUM_ITERS; i++) {
t0 = tick_ops->get_tick();
go[MASTER] = 1;
membar_safe("#StoreLoad");
while (!(tm = go[SLAVE]))
rmb();
go[SLAVE] = 0;
wmb();
t1 = tick_ops->get_tick();
if (t1 - t0 < best_t1 - best_t0)
best_t0 = t0, best_t1 = t1, best_tm = tm;
}
*rt = best_t1 - best_t0;
*master = best_tm - best_t0;
/* average best_t0 and best_t1 without overflow: */
tcenter = (best_t0/2 + best_t1/2);
if (best_t0 % 2 + best_t1 % 2 == 2)
tcenter++;
return tcenter - best_tm;
}
void smp_synchronize_tick_client(void)
{
long i, delta, adj, adjust_latency = 0, done = 0;
unsigned long flags, rt, master_time_stamp;
#if DEBUG_TICK_SYNC
struct {
long rt; /* roundtrip time */
long master; /* master's timestamp */
long diff; /* difference between midpoint and master's timestamp */
long lat; /* estimate of itc adjustment latency */
} t[NUM_ROUNDS];
#endif
go[MASTER] = 1;
while (go[MASTER])
rmb();
local_irq_save(flags);
{
for (i = 0; i < NUM_ROUNDS; i++) {
delta = get_delta(&rt, &master_time_stamp);
if (delta == 0)
done = 1; /* let's lock on to this... */
if (!done) {
if (i > 0) {
adjust_latency += -delta;
adj = -delta + adjust_latency/4;
} else
adj = -delta;
tick_ops->add_tick(adj);
}
#if DEBUG_TICK_SYNC
t[i].rt = rt;
t[i].master = master_time_stamp;
t[i].diff = delta;
t[i].lat = adjust_latency/4;
#endif
}
}
local_irq_restore(flags);
#if DEBUG_TICK_SYNC
for (i = 0; i < NUM_ROUNDS; i++)
printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
t[i].rt, t[i].master, t[i].diff, t[i].lat);
#endif
printk(KERN_INFO "CPU %d: synchronized TICK with master CPU "
"(last diff %ld cycles, maxerr %lu cycles)\n",
smp_processor_id(), delta, rt);
}
static void smp_start_sync_tick_client(int cpu);
static void smp_synchronize_one_tick(int cpu)
{
unsigned long flags, i;
go[MASTER] = 0;
smp_start_sync_tick_client(cpu);
/* wait for client to be ready */
while (!go[MASTER])
rmb();
/* now let the client proceed into his loop */
go[MASTER] = 0;
membar_safe("#StoreLoad");
raw_spin_lock_irqsave(&itc_sync_lock, flags);
{
for (i = 0; i < NUM_ROUNDS*NUM_ITERS; i++) {
while (!go[MASTER])
rmb();
go[MASTER] = 0;
wmb();
go[SLAVE] = tick_ops->get_tick();
membar_safe("#StoreLoad");
}
}
raw_spin_unlock_irqrestore(&itc_sync_lock, flags);
}
#if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
static void ldom_startcpu_cpuid(unsigned int cpu, unsigned long thread_reg,
void **descrp)
{
extern unsigned long sparc64_ttable_tl0;
extern unsigned long kern_locked_tte_data;
struct hvtramp_descr *hdesc;
unsigned long trampoline_ra;
struct trap_per_cpu *tb;
u64 tte_vaddr, tte_data;
unsigned long hv_err;
int i;
hdesc = kzalloc(sizeof(*hdesc) +
(sizeof(struct hvtramp_mapping) *
num_kernel_image_mappings - 1),
GFP_KERNEL);
if (!hdesc) {
printk(KERN_ERR "ldom_startcpu_cpuid: Cannot allocate "
"hvtramp_descr.\n");
return;
}
*descrp = hdesc;
hdesc->cpu = cpu;
hdesc->num_mappings = num_kernel_image_mappings;
tb = &trap_block[cpu];
hdesc->fault_info_va = (unsigned long) &tb->fault_info;
hdesc->fault_info_pa = kimage_addr_to_ra(&tb->fault_info);
hdesc->thread_reg = thread_reg;
tte_vaddr = (unsigned long) KERNBASE;
tte_data = kern_locked_tte_data;
for (i = 0; i < hdesc->num_mappings; i++) {
hdesc->maps[i].vaddr = tte_vaddr;
hdesc->maps[i].tte = tte_data;
tte_vaddr += 0x400000;
tte_data += 0x400000;
}
trampoline_ra = kimage_addr_to_ra(hv_cpu_startup);
hv_err = sun4v_cpu_start(cpu, trampoline_ra,
kimage_addr_to_ra(&sparc64_ttable_tl0),
__pa(hdesc));
if (hv_err)
printk(KERN_ERR "ldom_startcpu_cpuid: sun4v_cpu_start() "
"gives error %lu\n", hv_err);
}
#endif
extern unsigned long sparc64_cpu_startup;
/* The OBP cpu startup callback truncates the 3rd arg cookie to
* 32-bits (I think) so to be safe we have it read the pointer
* contained here so we work on >4GB machines. -DaveM
*/
static struct thread_info *cpu_new_thread = NULL;
static int smp_boot_one_cpu(unsigned int cpu, struct task_struct *idle)
{
unsigned long entry =
(unsigned long)(&sparc64_cpu_startup);
unsigned long cookie =
(unsigned long)(&cpu_new_thread);
void *descr = NULL;
int timeout, ret;
callin_flag = 0;
cpu_new_thread = task_thread_info(idle);
if (tlb_type == hypervisor) {
#if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
if (ldom_domaining_enabled)
ldom_startcpu_cpuid(cpu,
(unsigned long) cpu_new_thread,
&descr);
else
#endif
prom_startcpu_cpuid(cpu, entry, cookie);
} else {
struct device_node *dp = of_find_node_by_cpuid(cpu);
prom_startcpu(dp->phandle, entry, cookie);
}
for (timeout = 0; timeout < 50000; timeout++) {
if (callin_flag)
break;
udelay(100);
}
if (callin_flag) {
ret = 0;
} else {
printk("Processor %d is stuck.\n", cpu);
ret = -ENODEV;
}
cpu_new_thread = NULL;
kfree(descr);
return ret;
}
static void spitfire_xcall_helper(u64 data0, u64 data1, u64 data2, u64 pstate, unsigned long cpu)
{
u64 result, target;
int stuck, tmp;
if (this_is_starfire) {
/* map to real upaid */
cpu = (((cpu & 0x3c) << 1) |
((cpu & 0x40) >> 4) |
(cpu & 0x3));
}
target = (cpu << 14) | 0x70;
again:
/* Ok, this is the real Spitfire Errata #54.
* One must read back from a UDB internal register
* after writes to the UDB interrupt dispatch, but
* before the membar Sync for that write.
* So we use the high UDB control register (ASI 0x7f,
* ADDR 0x20) for the dummy read. -DaveM
*/
tmp = 0x40;
__asm__ __volatile__(
"wrpr %1, %2, %%pstate\n\t"
"stxa %4, [%0] %3\n\t"
"stxa %5, [%0+%8] %3\n\t"
"add %0, %8, %0\n\t"
"stxa %6, [%0+%8] %3\n\t"
"membar #Sync\n\t"
"stxa %%g0, [%7] %3\n\t"
"membar #Sync\n\t"
"mov 0x20, %%g1\n\t"
"ldxa [%%g1] 0x7f, %%g0\n\t"
"membar #Sync"
: "=r" (tmp)
: "r" (pstate), "i" (PSTATE_IE), "i" (ASI_INTR_W),
"r" (data0), "r" (data1), "r" (data2), "r" (target),
"r" (0x10), "0" (tmp)
: "g1");
/* NOTE: PSTATE_IE is still clear. */
stuck = 100000;
do {
__asm__ __volatile__("ldxa [%%g0] %1, %0"
: "=r" (result)
: "i" (ASI_INTR_DISPATCH_STAT));
if (result == 0) {
__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
: : "r" (pstate));
return;
}
stuck -= 1;
if (stuck == 0)
break;
} while (result & 0x1);
__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
: : "r" (pstate));
if (stuck == 0) {
printk("CPU[%d]: mondo stuckage result[%016llx]\n",
smp_processor_id(), result);
} else {
udelay(2);
goto again;
}
}
static void spitfire_xcall_deliver(struct trap_per_cpu *tb, int cnt)
{
u64 *mondo, data0, data1, data2;
u16 *cpu_list;
u64 pstate;
int i;
__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
cpu_list = __va(tb->cpu_list_pa);
mondo = __va(tb->cpu_mondo_block_pa);
data0 = mondo[0];
data1 = mondo[1];
data2 = mondo[2];
for (i = 0; i < cnt; i++)
spitfire_xcall_helper(data0, data1, data2, pstate, cpu_list[i]);
}
/* Cheetah now allows to send the whole 64-bytes of data in the interrupt
* packet, but we have no use for that. However we do take advantage of
* the new pipelining feature (ie. dispatch to multiple cpus simultaneously).
*/
static void cheetah_xcall_deliver(struct trap_per_cpu *tb, int cnt)
{
int nack_busy_id, is_jbus, need_more;
u64 *mondo, pstate, ver, busy_mask;
u16 *cpu_list;
cpu_list = __va(tb->cpu_list_pa);
mondo = __va(tb->cpu_mondo_block_pa);
/* Unfortunately, someone at Sun had the brilliant idea to make the
* busy/nack fields hard-coded by ITID number for this Ultra-III
* derivative processor.
*/
__asm__ ("rdpr %%ver, %0" : "=r" (ver));
is_jbus = ((ver >> 32) == __JALAPENO_ID ||
(ver >> 32) == __SERRANO_ID);
__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
retry:
need_more = 0;
__asm__ __volatile__("wrpr %0, %1, %%pstate\n\t"
: : "r" (pstate), "i" (PSTATE_IE));
/* Setup the dispatch data registers. */
__asm__ __volatile__("stxa %0, [%3] %6\n\t"
"stxa %1, [%4] %6\n\t"
"stxa %2, [%5] %6\n\t"
"membar #Sync\n\t"
: /* no outputs */
: "r" (mondo[0]), "r" (mondo[1]), "r" (mondo[2]),
"r" (0x40), "r" (0x50), "r" (0x60),
"i" (ASI_INTR_W));
nack_busy_id = 0;
busy_mask = 0;
{
int i;
for (i = 0; i < cnt; i++) {
u64 target, nr;
nr = cpu_list[i];
if (nr == 0xffff)
continue;
target = (nr << 14) | 0x70;
if (is_jbus) {
busy_mask |= (0x1UL << (nr * 2));
} else {
target |= (nack_busy_id << 24);
busy_mask |= (0x1UL <<
(nack_busy_id * 2));
}
__asm__ __volatile__(
"stxa %%g0, [%0] %1\n\t"
"membar #Sync\n\t"
: /* no outputs */
: "r" (target), "i" (ASI_INTR_W));
nack_busy_id++;
if (nack_busy_id == 32) {
need_more = 1;
break;
}
}
}
/* Now, poll for completion. */
{
u64 dispatch_stat, nack_mask;
long stuck;
stuck = 100000 * nack_busy_id;
nack_mask = busy_mask << 1;
do {
__asm__ __volatile__("ldxa [%%g0] %1, %0"
: "=r" (dispatch_stat)
: "i" (ASI_INTR_DISPATCH_STAT));
if (!(dispatch_stat & (busy_mask | nack_mask))) {
__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
: : "r" (pstate));
if (unlikely(need_more)) {
int i, this_cnt = 0;
for (i = 0; i < cnt; i++) {
if (cpu_list[i] == 0xffff)
continue;
cpu_list[i] = 0xffff;
this_cnt++;
if (this_cnt == 32)
break;
}
goto retry;
}
return;
}
if (!--stuck)
break;
} while (dispatch_stat & busy_mask);
__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
: : "r" (pstate));
if (dispatch_stat & busy_mask) {
/* Busy bits will not clear, continue instead
* of freezing up on this cpu.
*/
printk("CPU[%d]: mondo stuckage result[%016llx]\n",
smp_processor_id(), dispatch_stat);
} else {
int i, this_busy_nack = 0;
/* Delay some random time with interrupts enabled
* to prevent deadlock.
*/
udelay(2 * nack_busy_id);
/* Clear out the mask bits for cpus which did not
* NACK us.
*/
for (i = 0; i < cnt; i++) {
u64 check_mask, nr;
nr = cpu_list[i];
if (nr == 0xffff)
continue;
if (is_jbus)
check_mask = (0x2UL << (2*nr));
else
check_mask = (0x2UL <<
this_busy_nack);
if ((dispatch_stat & check_mask) == 0)
cpu_list[i] = 0xffff;
this_busy_nack += 2;
if (this_busy_nack == 64)
break;
}
goto retry;
}
}
}
#define CPU_MONDO_COUNTER(cpuid) (cpu_mondo_counter[cpuid])
#define MONDO_USEC_WAIT_MIN 2
#define MONDO_USEC_WAIT_MAX 100
#define MONDO_RETRY_LIMIT 500000
/* Multi-cpu list version.
*
* Deliver xcalls to 'cnt' number of cpus in 'cpu_list'.
* Sometimes not all cpus receive the mondo, requiring us to re-send
* the mondo until all cpus have received, or cpus are truly stuck
* unable to receive mondo, and we timeout.
* Occasionally a target cpu strand is borrowed briefly by hypervisor to
* perform guest service, such as PCIe error handling. Consider the
* service time, 1 second overall wait is reasonable for 1 cpu.
* Here two in-between mondo check wait time are defined: 2 usec for
* single cpu quick turn around and up to 100usec for large cpu count.
* Deliver mondo to large number of cpus could take longer, we adjusts
* the retry count as long as target cpus are making forward progress.
*/
static void hypervisor_xcall_deliver(struct trap_per_cpu *tb, int cnt)
{
int this_cpu, tot_cpus, prev_sent, i, rem;
int usec_wait, retries, tot_retries;
u16 first_cpu = 0xffff;
unsigned long xc_rcvd = 0;
unsigned long status;
int ecpuerror_id = 0;
int enocpu_id = 0;
u16 *cpu_list;
u16 cpu;
this_cpu = smp_processor_id();
cpu_list = __va(tb->cpu_list_pa);
usec_wait = cnt * MONDO_USEC_WAIT_MIN;
if (usec_wait > MONDO_USEC_WAIT_MAX)
usec_wait = MONDO_USEC_WAIT_MAX;
retries = tot_retries = 0;
tot_cpus = cnt;
prev_sent = 0;
do {
int n_sent, mondo_delivered, target_cpu_busy;
status = sun4v_cpu_mondo_send(cnt,
tb->cpu_list_pa,
tb->cpu_mondo_block_pa);
/* HV_EOK means all cpus received the xcall, we're done. */
if (likely(status == HV_EOK))
goto xcall_done;
/* If not these non-fatal errors, panic */
if (unlikely((status != HV_EWOULDBLOCK) &&
(status != HV_ECPUERROR) &&
(status != HV_ENOCPU)))
goto fatal_errors;
/* First, see if we made any forward progress.
*
* Go through the cpu_list, count the target cpus that have
* received our mondo (n_sent), and those that did not (rem).
* Re-pack cpu_list with the cpus remain to be retried in the
* front - this simplifies tracking the truly stalled cpus.
*
* The hypervisor indicates successful sends by setting
* cpu list entries to the value 0xffff.
*
* EWOULDBLOCK means some target cpus did not receive the
* mondo and retry usually helps.
*
* ECPUERROR means at least one target cpu is in error state,
* it's usually safe to skip the faulty cpu and retry.
*
* ENOCPU means one of the target cpu doesn't belong to the
* domain, perhaps offlined which is unexpected, but not
* fatal and it's okay to skip the offlined cpu.
*/
rem = 0;
n_sent = 0;
for (i = 0; i < cnt; i++) {
cpu = cpu_list[i];
if (likely(cpu == 0xffff)) {
n_sent++;
} else if ((status == HV_ECPUERROR) &&
(sun4v_cpu_state(cpu) == HV_CPU_STATE_ERROR)) {
ecpuerror_id = cpu + 1;
} else if (status == HV_ENOCPU && !cpu_online(cpu)) {
enocpu_id = cpu + 1;
} else {
cpu_list[rem++] = cpu;
}
}
/* No cpu remained, we're done. */
if (rem == 0)
break;
/* Otherwise, update the cpu count for retry. */
cnt = rem;
/* Record the overall number of mondos received by the
* first of the remaining cpus.
*/
if (first_cpu != cpu_list[0]) {
first_cpu = cpu_list[0];
xc_rcvd = CPU_MONDO_COUNTER(first_cpu);
}
/* Was any mondo delivered successfully? */
mondo_delivered = (n_sent > prev_sent);
prev_sent = n_sent;
/* or, was any target cpu busy processing other mondos? */
target_cpu_busy = (xc_rcvd < CPU_MONDO_COUNTER(first_cpu));
xc_rcvd = CPU_MONDO_COUNTER(first_cpu);
/* Retry count is for no progress. If we're making progress,
* reset the retry count.
*/
if (likely(mondo_delivered || target_cpu_busy)) {
tot_retries += retries;
retries = 0;
} else if (unlikely(retries > MONDO_RETRY_LIMIT)) {
goto fatal_mondo_timeout;
}
/* Delay a little bit to let other cpus catch up on
* their cpu mondo queue work.
*/
if (!mondo_delivered)
udelay(usec_wait);
retries++;
} while (1);
xcall_done:
if (unlikely(ecpuerror_id > 0)) {
pr_crit("CPU[%d]: SUN4V mondo cpu error, target cpu(%d) was in error state\n",
this_cpu, ecpuerror_id - 1);
} else if (unlikely(enocpu_id > 0)) {
pr_crit("CPU[%d]: SUN4V mondo cpu error, target cpu(%d) does not belong to the domain\n",
this_cpu, enocpu_id - 1);
}
return;
fatal_errors:
/* fatal errors include bad alignment, etc */
pr_crit("CPU[%d]: Args were cnt(%d) cpulist_pa(%lx) mondo_block_pa(%lx)\n",
this_cpu, tot_cpus, tb->cpu_list_pa, tb->cpu_mondo_block_pa);
panic("Unexpected SUN4V mondo error %lu\n", status);
fatal_mondo_timeout:
/* some cpus being non-responsive to the cpu mondo */
pr_crit("CPU[%d]: SUN4V mondo timeout, cpu(%d) made no forward progress after %d retries. Total target cpus(%d).\n",
this_cpu, first_cpu, (tot_retries + retries), tot_cpus);
panic("SUN4V mondo timeout panic\n");
}
static void (*xcall_deliver_impl)(struct trap_per_cpu *, int);
static void xcall_deliver(u64 data0, u64 data1, u64 data2, const cpumask_t *mask)
{
struct trap_per_cpu *tb;
int this_cpu, i, cnt;
unsigned long flags;
u16 *cpu_list;
u64 *mondo;
/* We have to do this whole thing with interrupts fully disabled.
* Otherwise if we send an xcall from interrupt context it will
* corrupt both our mondo block and cpu list state.
*
* One consequence of this is that we cannot use timeout mechanisms
* that depend upon interrupts being delivered locally. So, for
* example, we cannot sample jiffies and expect it to advance.
*
* Fortunately, udelay() uses %stick/%tick so we can use that.
*/
local_irq_save(flags);
this_cpu = smp_processor_id();
tb = &trap_block[this_cpu];
mondo = __va(tb->cpu_mondo_block_pa);
mondo[0] = data0;
mondo[1] = data1;
mondo[2] = data2;
wmb();
cpu_list = __va(tb->cpu_list_pa);
/* Setup the initial cpu list. */
cnt = 0;
for_each_cpu(i, mask) {
if (i == this_cpu || !cpu_online(i))
continue;
cpu_list[cnt++] = i;
}
if (cnt)
xcall_deliver_impl(tb, cnt);
local_irq_restore(flags);
}
/* Send cross call to all processors mentioned in MASK_P
* except self. Really, there are only two cases currently,
* "cpu_online_mask" and "mm_cpumask(mm)".
*/
static void smp_cross_call_masked(unsigned long *func, u32 ctx, u64 data1, u64 data2, const cpumask_t *mask)
{
u64 data0 = (((u64)ctx)<<32 | (((u64)func) & 0xffffffff));
xcall_deliver(data0, data1, data2, mask);
}
/* Send cross call to all processors except self. */
static void smp_cross_call(unsigned long *func, u32 ctx, u64 data1, u64 data2)
{
smp_cross_call_masked(func, ctx, data1, data2, cpu_online_mask);
}
extern unsigned long xcall_sync_tick;
static void smp_start_sync_tick_client(int cpu)
{
xcall_deliver((u64) &xcall_sync_tick, 0, 0,
cpumask_of(cpu));
}
extern unsigned long xcall_call_function;
void arch_send_call_function_ipi_mask(const struct cpumask *mask)
{
xcall_deliver((u64) &xcall_call_function, 0, 0, mask);
}
extern unsigned long xcall_call_function_single;
void arch_send_call_function_single_ipi(int cpu)
{
xcall_deliver((u64) &xcall_call_function_single, 0, 0,
cpumask_of(cpu));
}
void __irq_entry smp_call_function_client(int irq, struct pt_regs *regs)
{
clear_softint(1 << irq);
irq_enter();
generic_smp_call_function_interrupt();
irq_exit();
}
void __irq_entry smp_call_function_single_client(int irq, struct pt_regs *regs)
{
clear_softint(1 << irq);
irq_enter();
generic_smp_call_function_single_interrupt();
irq_exit();
}
static void tsb_sync(void *info)
{
struct trap_per_cpu *tp = &trap_block[raw_smp_processor_id()];
struct mm_struct *mm = info;
/* It is not valid to test "current->active_mm == mm" here.
*
* The value of "current" is not changed atomically with
* switch_mm(). But that's OK, we just need to check the
* current cpu's trap block PGD physical address.
*/
if (tp->pgd_paddr == __pa(mm->pgd))
tsb_context_switch(mm);
}
void smp_tsb_sync(struct mm_struct *mm)
{
smp_call_function_many(mm_cpumask(mm), tsb_sync, mm, 1);
}
extern unsigned long xcall_flush_tlb_mm;
extern unsigned long xcall_flush_tlb_page;
extern unsigned long xcall_flush_tlb_kernel_range;
extern unsigned long xcall_fetch_glob_regs;
extern unsigned long xcall_fetch_glob_pmu;
extern unsigned long xcall_fetch_glob_pmu_n4;
extern unsigned long xcall_receive_signal;
extern unsigned long xcall_new_mmu_context_version;
#ifdef CONFIG_KGDB
extern unsigned long xcall_kgdb_capture;
#endif
#ifdef DCACHE_ALIASING_POSSIBLE
extern unsigned long xcall_flush_dcache_page_cheetah;
#endif
extern unsigned long xcall_flush_dcache_page_spitfire;
static inline void __local_flush_dcache_page(struct page *page)
{
#ifdef DCACHE_ALIASING_POSSIBLE
__flush_dcache_page(page_address(page),
((tlb_type == spitfire) &&
page_mapping_file(page) != NULL));
#else
if (page_mapping_file(page) != NULL &&
tlb_type == spitfire)
__flush_icache_page(__pa(page_address(page)));
#endif
}
void smp_flush_dcache_page_impl(struct page *page, int cpu)
{
int this_cpu;
if (tlb_type == hypervisor)
return;
#ifdef CONFIG_DEBUG_DCFLUSH
atomic_inc(&dcpage_flushes);
#endif
this_cpu = get_cpu();
if (cpu == this_cpu) {
__local_flush_dcache_page(page);
} else if (cpu_online(cpu)) {
void *pg_addr = page_address(page);
u64 data0 = 0;
if (tlb_type == spitfire) {
data0 = ((u64)&xcall_flush_dcache_page_spitfire);
if (page_mapping_file(page) != NULL)
data0 |= ((u64)1 << 32);
} else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
#ifdef DCACHE_ALIASING_POSSIBLE
data0 = ((u64)&xcall_flush_dcache_page_cheetah);
#endif
}
if (data0) {
xcall_deliver(data0, __pa(pg_addr),
(u64) pg_addr, cpumask_of(cpu));
#ifdef CONFIG_DEBUG_DCFLUSH
atomic_inc(&dcpage_flushes_xcall);
#endif
}
}
put_cpu();
}
void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
{
void *pg_addr;
u64 data0;
if (tlb_type == hypervisor)
return;
preempt_disable();
#ifdef CONFIG_DEBUG_DCFLUSH
atomic_inc(&dcpage_flushes);
#endif
data0 = 0;
pg_addr = page_address(page);
if (tlb_type == spitfire) {
data0 = ((u64)&xcall_flush_dcache_page_spitfire);
if (page_mapping_file(page) != NULL)
data0 |= ((u64)1 << 32);
} else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
#ifdef DCACHE_ALIASING_POSSIBLE
data0 = ((u64)&xcall_flush_dcache_page_cheetah);
#endif
}
if (data0) {
xcall_deliver(data0, __pa(pg_addr),
(u64) pg_addr, cpu_online_mask);
#ifdef CONFIG_DEBUG_DCFLUSH
atomic_inc(&dcpage_flushes_xcall);
#endif
}
__local_flush_dcache_page(page);
preempt_enable();
}
#ifdef CONFIG_KGDB
void kgdb_roundup_cpus(void)
{
smp_cross_call(&xcall_kgdb_capture, 0, 0, 0);
}
#endif
void smp_fetch_global_regs(void)
{
smp_cross_call(&xcall_fetch_glob_regs, 0, 0, 0);
}
void smp_fetch_global_pmu(void)
{
if (tlb_type == hypervisor &&
sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
smp_cross_call(&xcall_fetch_glob_pmu_n4, 0, 0, 0);
else
smp_cross_call(&xcall_fetch_glob_pmu, 0, 0, 0);
}
/* We know that the window frames of the user have been flushed
* to the stack before we get here because all callers of us
* are flush_tlb_*() routines, and these run after flush_cache_*()
* which performs the flushw.
*
* mm->cpu_vm_mask is a bit mask of which cpus an address
* space has (potentially) executed on, this is the heuristic
* we use to limit cross calls.
*/
/* This currently is only used by the hugetlb arch pre-fault
* hook on UltraSPARC-III+ and later when changing the pagesize
* bits of the context register for an address space.
*/
void smp_flush_tlb_mm(struct mm_struct *mm)
{
u32 ctx = CTX_HWBITS(mm->context);
get_cpu();
smp_cross_call_masked(&xcall_flush_tlb_mm,
ctx, 0, 0,
mm_cpumask(mm));
__flush_tlb_mm(ctx, SECONDARY_CONTEXT);
put_cpu();
}
struct tlb_pending_info {
unsigned long ctx;
unsigned long nr;
unsigned long *vaddrs;
};
static void tlb_pending_func(void *info)
{
struct tlb_pending_info *t = info;
__flush_tlb_pending(t->ctx, t->nr, t->vaddrs);
}
void smp_flush_tlb_pending(struct mm_struct *mm, unsigned long nr, unsigned long *vaddrs)
{
u32 ctx = CTX_HWBITS(mm->context);
struct tlb_pending_info info;
get_cpu();
info.ctx = ctx;
info.nr = nr;
info.vaddrs = vaddrs;
smp_call_function_many(mm_cpumask(mm), tlb_pending_func,
&info, 1);
__flush_tlb_pending(ctx, nr, vaddrs);
put_cpu();
}
void smp_flush_tlb_page(struct mm_struct *mm, unsigned long vaddr)
{
unsigned long context = CTX_HWBITS(mm->context);
get_cpu();
smp_cross_call_masked(&xcall_flush_tlb_page,
context, vaddr, 0,
mm_cpumask(mm));
__flush_tlb_page(context, vaddr);
put_cpu();
}
void smp_flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
start &= PAGE_MASK;
end = PAGE_ALIGN(end);
if (start != end) {
smp_cross_call(&xcall_flush_tlb_kernel_range,
0, start, end);
__flush_tlb_kernel_range(start, end);
}
}
/* CPU capture. */
/* #define CAPTURE_DEBUG */
extern unsigned long xcall_capture;
static atomic_t smp_capture_depth = ATOMIC_INIT(0);
static atomic_t smp_capture_registry = ATOMIC_INIT(0);
static unsigned long penguins_are_doing_time;
void smp_capture(void)
{
int result = atomic_add_return(1, &smp_capture_depth);
if (result == 1) {
int ncpus = num_online_cpus();
#ifdef CAPTURE_DEBUG
printk("CPU[%d]: Sending penguins to jail...",
smp_processor_id());
#endif
penguins_are_doing_time = 1;
atomic_inc(&smp_capture_registry);
smp_cross_call(&xcall_capture, 0, 0, 0);
while (atomic_read(&smp_capture_registry) != ncpus)
rmb();
#ifdef CAPTURE_DEBUG
printk("done\n");
#endif
}
}
void smp_release(void)
{
if (atomic_dec_and_test(&smp_capture_depth)) {
#ifdef CAPTURE_DEBUG
printk("CPU[%d]: Giving pardon to "
"imprisoned penguins\n",
smp_processor_id());
#endif
penguins_are_doing_time = 0;
membar_safe("#StoreLoad");
atomic_dec(&smp_capture_registry);
}
}
/* Imprisoned penguins run with %pil == PIL_NORMAL_MAX, but PSTATE_IE
* set, so they can service tlb flush xcalls...
*/
extern void prom_world(int);
void __irq_entry smp_penguin_jailcell(int irq, struct pt_regs *regs)
{
clear_softint(1 << irq);
preempt_disable();
__asm__ __volatile__("flushw");
prom_world(1);
atomic_inc(&smp_capture_registry);
membar_safe("#StoreLoad");
while (penguins_are_doing_time)
rmb();
atomic_dec(&smp_capture_registry);
prom_world(0);
preempt_enable();
}
void __init smp_prepare_cpus(unsigned int max_cpus)
{
}
void smp_prepare_boot_cpu(void)
{
}
void __init smp_setup_processor_id(void)
{
if (tlb_type == spitfire)
xcall_deliver_impl = spitfire_xcall_deliver;
else if (tlb_type == cheetah || tlb_type == cheetah_plus)
xcall_deliver_impl = cheetah_xcall_deliver;
else
xcall_deliver_impl = hypervisor_xcall_deliver;
}
void __init smp_fill_in_cpu_possible_map(void)
{
int possible_cpus = num_possible_cpus();
int i;
if (possible_cpus > nr_cpu_ids)
possible_cpus = nr_cpu_ids;
for (i = 0; i < possible_cpus; i++)
set_cpu_possible(i, true);
for (; i < NR_CPUS; i++)
set_cpu_possible(i, false);
}
void smp_fill_in_sib_core_maps(void)
{
unsigned int i;
for_each_present_cpu(i) {
unsigned int j;
cpumask_clear(&cpu_core_map[i]);
if (cpu_data(i).core_id == 0) {
cpumask_set_cpu(i, &cpu_core_map[i]);
continue;
}
for_each_present_cpu(j) {
if (cpu_data(i).core_id ==
cpu_data(j).core_id)
cpumask_set_cpu(j, &cpu_core_map[i]);
}
}
for_each_present_cpu(i) {
unsigned int j;
for_each_present_cpu(j) {
if (cpu_data(i).max_cache_id ==
cpu_data(j).max_cache_id)
cpumask_set_cpu(j, &cpu_core_sib_cache_map[i]);
if (cpu_data(i).sock_id == cpu_data(j).sock_id)
cpumask_set_cpu(j, &cpu_core_sib_map[i]);
}
}
for_each_present_cpu(i) {
unsigned int j;
cpumask_clear(&per_cpu(cpu_sibling_map, i));
if (cpu_data(i).proc_id == -1) {
cpumask_set_cpu(i, &per_cpu(cpu_sibling_map, i));
continue;
}
for_each_present_cpu(j) {
if (cpu_data(i).proc_id ==
cpu_data(j).proc_id)
cpumask_set_cpu(j, &per_cpu(cpu_sibling_map, i));
}
}
}
int __cpu_up(unsigned int cpu, struct task_struct *tidle)
{
int ret = smp_boot_one_cpu(cpu, tidle);
if (!ret) {
cpumask_set_cpu(cpu, &smp_commenced_mask);
while (!cpu_online(cpu))
mb();
if (!cpu_online(cpu)) {
ret = -ENODEV;
} else {
/* On SUN4V, writes to %tick and %stick are
* not allowed.
*/
if (tlb_type != hypervisor)
smp_synchronize_one_tick(cpu);
}
}
return ret;
}
#ifdef CONFIG_HOTPLUG_CPU
void cpu_play_dead(void)
{
int cpu = smp_processor_id();
unsigned long pstate;
idle_task_exit();
if (tlb_type == hypervisor) {
struct trap_per_cpu *tb = &trap_block[cpu];
sun4v_cpu_qconf(HV_CPU_QUEUE_CPU_MONDO,
tb->cpu_mondo_pa, 0);
sun4v_cpu_qconf(HV_CPU_QUEUE_DEVICE_MONDO,
tb->dev_mondo_pa, 0);
sun4v_cpu_qconf(HV_CPU_QUEUE_RES_ERROR,
tb->resum_mondo_pa, 0);
sun4v_cpu_qconf(HV_CPU_QUEUE_NONRES_ERROR,
tb->nonresum_mondo_pa, 0);
}
cpumask_clear_cpu(cpu, &smp_commenced_mask);
membar_safe("#Sync");
local_irq_disable();
__asm__ __volatile__(
"rdpr %%pstate, %0\n\t"
"wrpr %0, %1, %%pstate"
: "=r" (pstate)
: "i" (PSTATE_IE));
while (1)
barrier();
}
int __cpu_disable(void)
{
int cpu = smp_processor_id();
cpuinfo_sparc *c;
int i;
for_each_cpu(i, &cpu_core_map[cpu])
cpumask_clear_cpu(cpu, &cpu_core_map[i]);
cpumask_clear(&cpu_core_map[cpu]);
for_each_cpu(i, &per_cpu(cpu_sibling_map, cpu))
cpumask_clear_cpu(cpu, &per_cpu(cpu_sibling_map, i));
cpumask_clear(&per_cpu(cpu_sibling_map, cpu));
c = &cpu_data(cpu);
c->core_id = 0;
c->proc_id = -1;
smp_wmb();
/* Make sure no interrupts point to this cpu. */
fixup_irqs();
local_irq_enable();
mdelay(1);
local_irq_disable();
set_cpu_online(cpu, false);
cpu_map_rebuild();
return 0;
}
void __cpu_die(unsigned int cpu)
{
int i;
for (i = 0; i < 100; i++) {
smp_rmb();
if (!cpumask_test_cpu(cpu, &smp_commenced_mask))
break;
msleep(100);
}
if (cpumask_test_cpu(cpu, &smp_commenced_mask)) {
printk(KERN_ERR "CPU %u didn't die...\n", cpu);
} else {
#if defined(CONFIG_SUN_LDOMS)
unsigned long hv_err;
int limit = 100;
do {
hv_err = sun4v_cpu_stop(cpu);
if (hv_err == HV_EOK) {
set_cpu_present(cpu, false);
break;
}
} while (--limit > 0);
if (limit <= 0) {
printk(KERN_ERR "sun4v_cpu_stop() fails err=%lu\n",
hv_err);
}
#endif
}
}
#endif
void __init smp_cpus_done(unsigned int max_cpus)
{
}
static void send_cpu_ipi(int cpu)
{
xcall_deliver((u64) &xcall_receive_signal,
0, 0, cpumask_of(cpu));
}
void scheduler_poke(void)
{
if (!cpu_poke)
return;
if (!__this_cpu_read(poke))
return;
__this_cpu_write(poke, false);
set_softint(1 << PIL_SMP_RECEIVE_SIGNAL);
}
static unsigned long send_cpu_poke(int cpu)
{
unsigned long hv_err;
per_cpu(poke, cpu) = true;
hv_err = sun4v_cpu_poke(cpu);
if (hv_err != HV_EOK) {
per_cpu(poke, cpu) = false;
pr_err_ratelimited("%s: sun4v_cpu_poke() fails err=%lu\n",
__func__, hv_err);
}
return hv_err;
}
void smp_send_reschedule(int cpu)
{
if (cpu == smp_processor_id()) {
WARN_ON_ONCE(preemptible());
set_softint(1 << PIL_SMP_RECEIVE_SIGNAL);
return;
}
/* Use cpu poke to resume idle cpu if supported. */
if (cpu_poke && idle_cpu(cpu)) {
unsigned long ret;
ret = send_cpu_poke(cpu);
if (ret == HV_EOK)
return;
}
/* Use IPI in following cases:
* - cpu poke not supported
* - cpu not idle
* - send_cpu_poke() returns with error
*/
send_cpu_ipi(cpu);
}
void smp_init_cpu_poke(void)
{
unsigned long major;
unsigned long minor;
int ret;
if (tlb_type != hypervisor)
return;
ret = sun4v_hvapi_get(HV_GRP_CORE, &major, &minor);
if (ret) {
pr_debug("HV_GRP_CORE is not registered\n");
return;
}
if (major == 1 && minor >= 6) {
/* CPU POKE is registered. */
cpu_poke = true;
return;
}
pr_debug("CPU_POKE not supported\n");
}
void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs)
{
clear_softint(1 << irq);
scheduler_ipi();
}
static void stop_this_cpu(void *dummy)
{
set_cpu_online(smp_processor_id(), false);
prom_stopself();
}
void smp_send_stop(void)
{
int cpu;
if (tlb_type == hypervisor) {
int this_cpu = smp_processor_id();
#ifdef CONFIG_SERIAL_SUNHV
sunhv_migrate_hvcons_irq(this_cpu);
#endif
for_each_online_cpu(cpu) {
if (cpu == this_cpu)
continue;
set_cpu_online(cpu, false);
#ifdef CONFIG_SUN_LDOMS
if (ldom_domaining_enabled) {
unsigned long hv_err;
hv_err = sun4v_cpu_stop(cpu);
if (hv_err)
printk(KERN_ERR "sun4v_cpu_stop() "
"failed err=%lu\n", hv_err);
} else
#endif
prom_stopcpu_cpuid(cpu);
}
} else
smp_call_function(stop_this_cpu, NULL, 0);
}
static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
{
if (cpu_to_node(from) == cpu_to_node(to))
return LOCAL_DISTANCE;
else
return REMOTE_DISTANCE;
}
static int __init pcpu_cpu_to_node(int cpu)
{
return cpu_to_node(cpu);
}
void __init setup_per_cpu_areas(void)
{
unsigned long delta;
unsigned int cpu;
int rc = -EINVAL;
if (pcpu_chosen_fc != PCPU_FC_PAGE) {
rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
PERCPU_DYNAMIC_RESERVE, 4 << 20,
pcpu_cpu_distance,
pcpu_cpu_to_node);
if (rc)
pr_warn("PERCPU: %s allocator failed (%d), "
"falling back to page size\n",
pcpu_fc_names[pcpu_chosen_fc], rc);
}
if (rc < 0)
rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE,
pcpu_cpu_to_node);
if (rc < 0)
panic("cannot initialize percpu area (err=%d)", rc);
delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
for_each_possible_cpu(cpu)
__per_cpu_offset(cpu) = delta + pcpu_unit_offsets[cpu];
/* Setup %g5 for the boot cpu. */
__local_per_cpu_offset = __per_cpu_offset(smp_processor_id());
of_fill_in_cpu_data();
if (tlb_type == hypervisor)
mdesc_fill_in_cpu_data(cpu_all_mask);
}