#include <linux/types.h>
#include <asm/delay.h>
#include <irq.h>
#include <hwregs/intr_vect.h>
#include <hwregs/intr_vect_defs.h>
#include <asm/tlbflush.h>
#include <asm/mmu_context.h>
#include <hwregs/asm/mmu_defs_asm.h>
#include <hwregs/supp_reg.h>
#include <asm/atomic.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/timex.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/cpumask.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#define IPI_SCHEDULE 1
#define IPI_CALL 2
#define IPI_FLUSH_TLB 4
#define IPI_BOOT 8
#define FLUSH_ALL (void*)0xffffffff
/* Vector of locks used for various atomic operations */
spinlock_t cris_atomic_locks[] = { [0 ... LOCK_COUNT - 1] = SPIN_LOCK_UNLOCKED};
/* CPU masks */
cpumask_t phys_cpu_present_map = CPU_MASK_NONE;
EXPORT_SYMBOL(phys_cpu_present_map);
/* Variables used during SMP boot */
volatile int cpu_now_booting = 0;
volatile struct thread_info *smp_init_current_idle_thread;
/* Variables used during IPI */
static DEFINE_SPINLOCK(call_lock);
static DEFINE_SPINLOCK(tlbstate_lock);
struct call_data_struct {
void (*func) (void *info);
void *info;
int wait;
};
static struct call_data_struct * call_data;
static struct mm_struct* flush_mm;
static struct vm_area_struct* flush_vma;
static unsigned long flush_addr;
extern int setup_irq(int, struct irqaction *);
/* Mode registers */
static unsigned long irq_regs[NR_CPUS] = {
regi_irq,
regi_irq2
};
static irqreturn_t crisv32_ipi_interrupt(int irq, void *dev_id);
static int send_ipi(int vector, int wait, cpumask_t cpu_mask);
static struct irqaction irq_ipi = {
.handler = crisv32_ipi_interrupt,
.flags = IRQF_DISABLED,
.name = "ipi",
};
extern void cris_mmu_init(void);
extern void cris_timer_init(void);
/* SMP initialization */
void __init smp_prepare_cpus(unsigned int max_cpus)
{
int i;
/* From now on we can expect IPIs so set them up */
setup_irq(IPI_INTR_VECT, &irq_ipi);
/* Mark all possible CPUs as present */
for (i = 0; i < max_cpus; i++)
cpu_set(i, phys_cpu_present_map);
}
void __devinit smp_prepare_boot_cpu(void)
{
/* PGD pointer has moved after per_cpu initialization so
* update the MMU.
*/
pgd_t **pgd;
pgd = (pgd_t**)&per_cpu(current_pgd, smp_processor_id());
SUPP_BANK_SEL(1);
SUPP_REG_WR(RW_MM_TLB_PGD, pgd);
SUPP_BANK_SEL(2);
SUPP_REG_WR(RW_MM_TLB_PGD, pgd);
cpu_set(0, cpu_online_map);
cpu_set(0, phys_cpu_present_map);
cpu_set(0, cpu_possible_map);
}
void __init smp_cpus_done(unsigned int max_cpus)
{
}
/* Bring one cpu online.*/
static int __init
smp_boot_one_cpu(int cpuid)
{
unsigned timeout;
struct task_struct *idle;
cpumask_t cpu_mask = CPU_MASK_NONE;
idle = fork_idle(cpuid);
if (IS_ERR(idle))
panic("SMP: fork failed for CPU:%d", cpuid);
task_thread_info(idle)->cpu = cpuid;
/* Information to the CPU that is about to boot */
smp_init_current_idle_thread = task_thread_info(idle);
cpu_now_booting = cpuid;
/* Kick it */
cpu_set(cpuid, cpu_online_map);
cpu_set(cpuid, cpu_mask);
send_ipi(IPI_BOOT, 0, cpu_mask);
cpu_clear(cpuid, cpu_online_map);
/* Wait for CPU to come online */
for (timeout = 0; timeout < 10000; timeout++) {
if(cpu_online(cpuid)) {
cpu_now_booting = 0;
smp_init_current_idle_thread = NULL;
return 0; /* CPU online */
}
udelay(100);
barrier();
}
put_task_struct(idle);
idle = NULL;
printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
return -1;
}
/* Secondary CPUs starts using C here. Here we need to setup CPU
* specific stuff such as the local timer and the MMU. */
void __init smp_callin(void)
{
extern void cpu_idle(void);
int cpu = cpu_now_booting;
reg_intr_vect_rw_mask vect_mask = {0};
/* Initialise the idle task for this CPU */
atomic_inc(&init_mm.mm_count);
current->active_mm = &init_mm;
/* Set up MMU */
cris_mmu_init();
__flush_tlb_all();
/* Setup local timer. */
cris_timer_init();
/* Enable IRQ and idle */
REG_WR(intr_vect, irq_regs[cpu], rw_mask, vect_mask);
unmask_irq(IPI_INTR_VECT);
unmask_irq(TIMER0_INTR_VECT);
preempt_disable();
notify_cpu_starting(cpu);
local_irq_enable();
cpu_set(cpu, cpu_online_map);
cpu_idle();
}
/* Stop execution on this CPU.*/
void stop_this_cpu(void* dummy)
{
local_irq_disable();
asm volatile("halt");
}
/* Other calls */
void smp_send_stop(void)
{
smp_call_function(stop_this_cpu, NULL, 0);
}
int setup_profiling_timer(unsigned int multiplier)
{
return -EINVAL;
}
/* cache_decay_ticks is used by the scheduler to decide if a process
* is "hot" on one CPU. A higher value means a higher penalty to move
* a process to another CPU. Our cache is rather small so we report
* 1 tick.
*/
unsigned long cache_decay_ticks = 1;
int __cpuinit __cpu_up(unsigned int cpu)
{
smp_boot_one_cpu(cpu);
return cpu_online(cpu) ? 0 : -ENOSYS;
}
void smp_send_reschedule(int cpu)
{
cpumask_t cpu_mask = CPU_MASK_NONE;
cpu_set(cpu, cpu_mask);
send_ipi(IPI_SCHEDULE, 0, cpu_mask);
}
/* TLB flushing
*
* Flush needs to be done on the local CPU and on any other CPU that
* may have the same mapping. The mm->cpu_vm_mask is used to keep track
* of which CPUs that a specific process has been executed on.
*/
void flush_tlb_common(struct mm_struct* mm, struct vm_area_struct* vma, unsigned long addr)
{
unsigned long flags;
cpumask_t cpu_mask;
spin_lock_irqsave(&tlbstate_lock, flags);
cpu_mask = (mm == FLUSH_ALL ? CPU_MASK_ALL : mm->cpu_vm_mask);
cpu_clear(smp_processor_id(), cpu_mask);
flush_mm = mm;
flush_vma = vma;
flush_addr = addr;
send_ipi(IPI_FLUSH_TLB, 1, cpu_mask);
spin_unlock_irqrestore(&tlbstate_lock, flags);
}
void flush_tlb_all(void)
{
__flush_tlb_all();
flush_tlb_common(FLUSH_ALL, FLUSH_ALL, 0);
}
void flush_tlb_mm(struct mm_struct *mm)
{
__flush_tlb_mm(mm);
flush_tlb_common(mm, FLUSH_ALL, 0);
/* No more mappings in other CPUs */
cpus_clear(mm->cpu_vm_mask);
cpu_set(smp_processor_id(), mm->cpu_vm_mask);
}
void flush_tlb_page(struct vm_area_struct *vma,
unsigned long addr)
{
__flush_tlb_page(vma, addr);
flush_tlb_common(vma->vm_mm, vma, addr);
}
/* Inter processor interrupts
*
* The IPIs are used for:
* * Force a schedule on a CPU
* * FLush TLB on other CPUs
* * Call a function on other CPUs
*/
int send_ipi(int vector, int wait, cpumask_t cpu_mask)
{
int i = 0;
reg_intr_vect_rw_ipi ipi = REG_RD(intr_vect, irq_regs[i], rw_ipi);
int ret = 0;
/* Calculate CPUs to send to. */
cpus_and(cpu_mask, cpu_mask, cpu_online_map);
/* Send the IPI. */
for_each_cpu_mask(i, cpu_mask)
{
ipi.vector |= vector;
REG_WR(intr_vect, irq_regs[i], rw_ipi, ipi);
}
/* Wait for IPI to finish on other CPUS */
if (wait) {
for_each_cpu_mask(i, cpu_mask) {
int j;
for (j = 0 ; j < 1000; j++) {
ipi = REG_RD(intr_vect, irq_regs[i], rw_ipi);
if (!ipi.vector)
break;
udelay(100);
}
/* Timeout? */
if (ipi.vector) {
printk("SMP call timeout from %d to %d\n", smp_processor_id(), i);
ret = -ETIMEDOUT;
dump_stack();
}
}
}
return ret;
}
/*
* You must not call this function with disabled interrupts or from a
* hardware interrupt handler or from a bottom half handler.
*/
int smp_call_function(void (*func)(void *info), void *info, int wait)
{
cpumask_t cpu_mask = CPU_MASK_ALL;
struct call_data_struct data;
int ret;
cpu_clear(smp_processor_id(), cpu_mask);
WARN_ON(irqs_disabled());
data.func = func;
data.info = info;
data.wait = wait;
spin_lock(&call_lock);
call_data = &data;
ret = send_ipi(IPI_CALL, wait, cpu_mask);
spin_unlock(&call_lock);
return ret;
}
irqreturn_t crisv32_ipi_interrupt(int irq, void *dev_id)
{
void (*func) (void *info) = call_data->func;
void *info = call_data->info;
reg_intr_vect_rw_ipi ipi;
ipi = REG_RD(intr_vect, irq_regs[smp_processor_id()], rw_ipi);
if (ipi.vector & IPI_CALL) {
func(info);
}
if (ipi.vector & IPI_FLUSH_TLB) {
if (flush_mm == FLUSH_ALL)
__flush_tlb_all();
else if (flush_vma == FLUSH_ALL)
__flush_tlb_mm(flush_mm);
else
__flush_tlb_page(flush_vma, flush_addr);
}
ipi.vector = 0;
REG_WR(intr_vect, irq_regs[smp_processor_id()], rw_ipi, ipi);
return IRQ_HANDLED;
}
