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#include <linux/config.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/threads.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/sched.h>
#include <linux/cache.h>
#include <asm/atomic.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/hardirq.h>
#include <asm/softirq.h>
#include <asm/mmu_context.h>
#include <asm/irq.h>
#ifdef CONFIG_SGI_IP27
#include <asm/sn/arch.h>
#include <asm/sn/intr.h>
#include <asm/sn/addrs.h>
#include <asm/sn/agent.h>
#include <asm/sn/sn0/ip27.h>
#define DORESCHED 0xab
#define DOCALL 0xbc
static void sendintr(int destid, unsigned char status)
{
int irq;
#if (CPUS_PER_NODE == 2)
switch (status) {
case DORESCHED: irq = CPU_RESCHED_A_IRQ; break;
case DOCALL: irq = CPU_CALL_A_IRQ; break;
default: panic("sendintr");
}
irq += cputoslice(destid);
/*
* Convert the compact hub number to the NASID to get the correct
* part of the address space. Then set the interrupt bit associated
* with the CPU we want to send the interrupt to.
*/
REMOTE_HUB_SEND_INTR(COMPACT_TO_NASID_NODEID(cputocnode(destid)),
FAST_IRQ_TO_LEVEL(irq));
#else
<< Bomb! Must redefine this for more than 2 CPUS. >>
#endif
}
#endif /* CONFIG_SGI_IP27 */
/* The 'big kernel lock' */
spinlock_t kernel_flag __cacheline_aligned_in_smp = SPIN_LOCK_UNLOCKED;
int smp_threads_ready; /* Not used */
atomic_t smp_commenced = ATOMIC_INIT(0);
struct cpuinfo_mips cpu_data[NR_CPUS];
int smp_num_cpus = 1; /* Number that came online. */
int __cpu_number_map[NR_CPUS];
int __cpu_logical_map[NR_CPUS];
cycles_t cacheflush_time;
static void smp_tune_scheduling (void)
{
}
void __init smp_boot_cpus(void)
{
extern void allowboot(void);
init_new_context(current, &init_mm);
current->processor = 0;
init_idle();
smp_tune_scheduling();
allowboot();
}
void __init smp_commence(void)
{
wmb();
atomic_set(&smp_commenced,1);
}
static void stop_this_cpu(void *dummy)
{
/*
* Remove this CPU
*/
for (;;);
}
void smp_send_stop(void)
{
smp_call_function(stop_this_cpu, NULL, 1, 0);
smp_num_cpus = 1;
}
/*
* this function sends a 'reschedule' IPI to another CPU.
* it goes straight through and wastes no time serializing
* anything. Worst case is that we lose a reschedule ...
*/
void smp_send_reschedule(int cpu)
{
sendintr(cpu, DORESCHED);
}
/* Not really SMP stuff ... */
int setup_profiling_timer(unsigned int multiplier)
{
return 0;
}
/*
* Run a function on all other CPUs.
* <func> The function to run. This must be fast and non-blocking.
* <info> An arbitrary pointer to pass to the function.
* <retry> If true, keep retrying until ready.
* <wait> If true, wait until function has completed on other CPUs.
* [RETURNS] 0 on success, else a negative status code.
*
* Does not return until remote CPUs are nearly ready to execute <func>
* or are or have executed.
*/
static volatile struct call_data_struct {
void (*func) (void *info);
void *info;
atomic_t started;
atomic_t finished;
int wait;
} *call_data;
int smp_call_function (void (*func) (void *info), void *info, int retry,
int wait)
{
struct call_data_struct data;
int i, cpus = smp_num_cpus-1;
static spinlock_t lock = SPIN_LOCK_UNLOCKED;
if (cpus == 0)
return 0;
data.func = func;
data.info = info;
atomic_set(&data.started, 0);
data.wait = wait;
if (wait)
atomic_set(&data.finished, 0);
spin_lock_bh(&lock);
call_data = &data;
/* Send a message to all other CPUs and wait for them to respond */
for (i = 0; i < smp_num_cpus; i++)
if (smp_processor_id() != i)
sendintr(i, DOCALL);
/* Wait for response */
/* FIXME: lock-up detection, backtrace on lock-up */
while (atomic_read(&data.started) != cpus)
barrier();
if (wait)
while (atomic_read(&data.finished) != cpus)
barrier();
spin_unlock_bh(&lock);
return 0;
}
extern void smp_call_function_interrupt(int irq, void *d, struct pt_regs *r)
{
void (*func) (void *info) = call_data->func;
void *info = call_data->info;
int wait = call_data->wait;
/*
* Notify initiating CPU that I've grabbed the data and am
* about to execute the function.
*/
atomic_inc(&call_data->started);
/*
* At this point the info structure may be out of scope unless wait==1.
*/
(*func)(info);
if (wait)
atomic_inc(&call_data->finished);
}
static void flush_tlb_all_ipi(void *info)
{
_flush_tlb_all();
}
void flush_tlb_all(void)
{
smp_call_function(flush_tlb_all_ipi, 0, 1, 1);
_flush_tlb_all();
}
static void flush_tlb_mm_ipi(void *mm)
{
_flush_tlb_mm((struct mm_struct *)mm);
}
/*
* The following tlb flush calls are invoked when old translations are
* being torn down, or pte attributes are changing. For single threaded
* address spaces, a new context is obtained on the current cpu, and tlb
* context on other cpus are invalidated to force a new context allocation
* at switch_mm time, should the mm ever be used on other cpus. For
* multithreaded address spaces, intercpu interrupts have to be sent.
* Another case where intercpu interrupts are required is when the target
* mm might be active on another cpu (eg debuggers doing the flushes on
* behalf of debugees, kswapd stealing pages from another process etc).
* Kanoj 07/00.
*/
void flush_tlb_mm(struct mm_struct *mm)
{
if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) {
smp_call_function(flush_tlb_mm_ipi, (void *)mm, 1, 1);
} else {
int i;
for (i = 0; i < smp_num_cpus; i++)
if (smp_processor_id() != i)
CPU_CONTEXT(i, mm) = 0;
}
_flush_tlb_mm(mm);
}
struct flush_tlb_data {
struct mm_struct *mm;
struct vm_area_struct *vma;
unsigned long addr1;
unsigned long addr2;
};
static void flush_tlb_range_ipi(void *info)
{
struct flush_tlb_data *fd = (struct flush_tlb_data *)info;
_flush_tlb_range(fd->mm, fd->addr1, fd->addr2);
}
void flush_tlb_range(struct mm_struct *mm, unsigned long start, unsigned long end)
{
if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) {
struct flush_tlb_data fd;
fd.mm = mm;
fd.addr1 = start;
fd.addr2 = end;
smp_call_function(flush_tlb_range_ipi, (void *)&fd, 1, 1);
} else {
int i;
for (i = 0; i < smp_num_cpus; i++)
if (smp_processor_id() != i)
CPU_CONTEXT(i, mm) = 0;
}
_flush_tlb_range(mm, start, end);
}
static void flush_tlb_page_ipi(void *info)
{
struct flush_tlb_data *fd = (struct flush_tlb_data *)info;
_flush_tlb_page(fd->vma, fd->addr1);
}
void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
{
if ((atomic_read(&vma->vm_mm->mm_users) != 1) || (current->mm != vma->vm_mm)) {
struct flush_tlb_data fd;
fd.vma = vma;
fd.addr1 = page;
smp_call_function(flush_tlb_page_ipi, (void *)&fd, 1, 1);
} else {
int i;
for (i = 0; i < smp_num_cpus; i++)
if (smp_processor_id() != i)
CPU_CONTEXT(i, vma->vm_mm) = 0;
}
_flush_tlb_page(vma, page);
}
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