 59f0eaaacd
			
		
	
	
	59f0eaaacd
	
	
	
		
			
			Introduced by commit 25d67f860f ("bfin: Use generic idle loop").
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
		
	
			
		
			
				
	
	
		
			434 lines
		
	
	
	
		
			11 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			434 lines
		
	
	
	
		
			11 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Blackfin architecture-dependent process handling
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|  *
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|  * Copyright 2004-2009 Analog Devices Inc.
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|  *
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|  * Licensed under the GPL-2 or later
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|  */
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| 
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| #include <linux/module.h>
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| #include <linux/unistd.h>
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| #include <linux/user.h>
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| #include <linux/uaccess.h>
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| #include <linux/slab.h>
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| #include <linux/sched.h>
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| #include <linux/tick.h>
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| #include <linux/fs.h>
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| #include <linux/err.h>
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| 
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| #include <asm/blackfin.h>
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| #include <asm/fixed_code.h>
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| #include <asm/mem_map.h>
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| #include <asm/irq.h>
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| 
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| asmlinkage void ret_from_fork(void);
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| 
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| /* Points to the SDRAM backup memory for the stack that is currently in
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|  * L1 scratchpad memory.
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|  */
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| void *current_l1_stack_save;
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| 
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| /* The number of tasks currently using a L1 stack area.  The SRAM is
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|  * allocated/deallocated whenever this changes from/to zero.
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|  */
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| int nr_l1stack_tasks;
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| 
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| /* Start and length of the area in L1 scratchpad memory which we've allocated
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|  * for process stacks.
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|  */
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| void *l1_stack_base;
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| unsigned long l1_stack_len;
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| 
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| void (*pm_power_off)(void) = NULL;
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| EXPORT_SYMBOL(pm_power_off);
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| 
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| /*
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|  * The idle loop on BFIN
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|  */
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| #ifdef CONFIG_IDLE_L1
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| void arch_cpu_idle(void)__attribute__((l1_text));
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| #endif
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| 
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| /*
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|  * This is our default idle handler.  We need to disable
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|  * interrupts here to ensure we don't miss a wakeup call.
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|  */
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| void arch_cpu_idle(void)
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| {
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| #ifdef CONFIG_IPIPE
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| 	ipipe_suspend_domain();
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| #endif
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| 	hard_local_irq_disable();
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| 	if (!need_resched())
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| 		idle_with_irq_disabled();
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| 
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| 	hard_local_irq_enable();
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| }
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| 
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| #ifdef CONFIG_HOTPLUG_CPU
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| void arch_cpu_idle_dead(void)
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| {
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| 	cpu_die();
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| }
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| #endif
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| 
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| /*
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|  * Do necessary setup to start up a newly executed thread.
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|  *
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|  * pass the data segment into user programs if it exists,
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|  * it can't hurt anything as far as I can tell
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|  */
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| void start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
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| {
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| 	regs->pc = new_ip;
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| 	if (current->mm)
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| 		regs->p5 = current->mm->start_data;
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| #ifndef CONFIG_SMP
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| 	task_thread_info(current)->l1_task_info.stack_start =
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| 		(void *)current->mm->context.stack_start;
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| 	task_thread_info(current)->l1_task_info.lowest_sp = (void *)new_sp;
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| 	memcpy(L1_SCRATCH_TASK_INFO, &task_thread_info(current)->l1_task_info,
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| 	       sizeof(*L1_SCRATCH_TASK_INFO));
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| #endif
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| 	wrusp(new_sp);
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| }
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| EXPORT_SYMBOL_GPL(start_thread);
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| 
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| void flush_thread(void)
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| {
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| }
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| 
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| asmlinkage int bfin_clone(unsigned long clone_flags, unsigned long newsp)
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| {
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| #ifdef __ARCH_SYNC_CORE_DCACHE
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| 	if (current->nr_cpus_allowed == num_possible_cpus())
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| 		set_cpus_allowed_ptr(current, cpumask_of(smp_processor_id()));
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| #endif
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| 	if (newsp)
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| 		newsp -= 12;
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| 	return do_fork(clone_flags, newsp, 0, NULL, NULL);
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| }
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| 
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| int
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| copy_thread(unsigned long clone_flags,
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| 	    unsigned long usp, unsigned long topstk,
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| 	    struct task_struct *p)
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| {
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| 	struct pt_regs *childregs;
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| 	unsigned long *v;
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| 
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| 	childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
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| 	v = ((unsigned long *)childregs) - 2;
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| 	if (unlikely(p->flags & PF_KTHREAD)) {
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| 		memset(childregs, 0, sizeof(struct pt_regs));
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| 		v[0] = usp;
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| 		v[1] = topstk;
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| 		childregs->orig_p0 = -1;
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| 		childregs->ipend = 0x8000;
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| 		__asm__ __volatile__("%0 = syscfg;":"=da"(childregs->syscfg):);
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| 		p->thread.usp = 0;
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| 	} else {
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| 		*childregs = *current_pt_regs();
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| 		childregs->r0 = 0;
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| 		p->thread.usp = usp ? : rdusp();
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| 		v[0] = v[1] = 0;
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| 	}
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| 
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| 	p->thread.ksp = (unsigned long)v;
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| 	p->thread.pc = (unsigned long)ret_from_fork;
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| 
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| 	return 0;
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| }
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| 
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| unsigned long get_wchan(struct task_struct *p)
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| {
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| 	unsigned long fp, pc;
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| 	unsigned long stack_page;
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| 	int count = 0;
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| 	if (!p || p == current || p->state == TASK_RUNNING)
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| 		return 0;
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| 
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| 	stack_page = (unsigned long)p;
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| 	fp = p->thread.usp;
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| 	do {
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| 		if (fp < stack_page + sizeof(struct thread_info) ||
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| 		    fp >= 8184 + stack_page)
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| 			return 0;
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| 		pc = ((unsigned long *)fp)[1];
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| 		if (!in_sched_functions(pc))
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| 			return pc;
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| 		fp = *(unsigned long *)fp;
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| 	}
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| 	while (count++ < 16);
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| 	return 0;
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| }
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| 
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| void finish_atomic_sections (struct pt_regs *regs)
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| {
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| 	int __user *up0 = (int __user *)regs->p0;
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| 
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| 	switch (regs->pc) {
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| 	default:
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| 		/* not in middle of an atomic step, so resume like normal */
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| 		return;
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| 
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| 	case ATOMIC_XCHG32 + 2:
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| 		put_user(regs->r1, up0);
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| 		break;
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| 
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| 	case ATOMIC_CAS32 + 2:
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| 	case ATOMIC_CAS32 + 4:
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| 		if (regs->r0 == regs->r1)
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| 	case ATOMIC_CAS32 + 6:
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| 			put_user(regs->r2, up0);
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| 		break;
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| 
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| 	case ATOMIC_ADD32 + 2:
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| 		regs->r0 = regs->r1 + regs->r0;
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| 		/* fall through */
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| 	case ATOMIC_ADD32 + 4:
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| 		put_user(regs->r0, up0);
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| 		break;
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| 
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| 	case ATOMIC_SUB32 + 2:
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| 		regs->r0 = regs->r1 - regs->r0;
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| 		/* fall through */
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| 	case ATOMIC_SUB32 + 4:
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| 		put_user(regs->r0, up0);
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| 		break;
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| 
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| 	case ATOMIC_IOR32 + 2:
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| 		regs->r0 = regs->r1 | regs->r0;
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| 		/* fall through */
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| 	case ATOMIC_IOR32 + 4:
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| 		put_user(regs->r0, up0);
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| 		break;
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| 
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| 	case ATOMIC_AND32 + 2:
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| 		regs->r0 = regs->r1 & regs->r0;
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| 		/* fall through */
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| 	case ATOMIC_AND32 + 4:
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| 		put_user(regs->r0, up0);
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| 		break;
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| 
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| 	case ATOMIC_XOR32 + 2:
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| 		regs->r0 = regs->r1 ^ regs->r0;
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| 		/* fall through */
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| 	case ATOMIC_XOR32 + 4:
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| 		put_user(regs->r0, up0);
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| 		break;
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| 	}
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| 
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| 	/*
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| 	 * We've finished the atomic section, and the only thing left for
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| 	 * userspace is to do a RTS, so we might as well handle that too
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| 	 * since we need to update the PC anyways.
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| 	 */
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| 	regs->pc = regs->rets;
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| }
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| 
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| static inline
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| int in_mem(unsigned long addr, unsigned long size,
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|            unsigned long start, unsigned long end)
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| {
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| 	return addr >= start && addr + size <= end;
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| }
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| static inline
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| int in_mem_const_off(unsigned long addr, unsigned long size, unsigned long off,
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|                      unsigned long const_addr, unsigned long const_size)
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| {
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| 	return const_size &&
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| 	       in_mem(addr, size, const_addr + off, const_addr + const_size);
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| }
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| static inline
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| int in_mem_const(unsigned long addr, unsigned long size,
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|                  unsigned long const_addr, unsigned long const_size)
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| {
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| 	return in_mem_const_off(addr, size, 0, const_addr, const_size);
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| }
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| #ifdef CONFIG_BF60x
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| #define ASYNC_ENABLED(bnum, bctlnum)	1
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| #else
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| #define ASYNC_ENABLED(bnum, bctlnum) \
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| ({ \
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| 	(bfin_read_EBIU_AMGCTL() & 0xe) < ((bnum + 1) << 1) ? 0 : \
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| 	bfin_read_EBIU_AMBCTL##bctlnum() & B##bnum##RDYEN ? 0 : \
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| 	1; \
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| })
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| #endif
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| /*
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|  * We can't read EBIU banks that aren't enabled or we end up hanging
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|  * on the access to the async space.  Make sure we validate accesses
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|  * that cross async banks too.
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|  *	0 - found, but unusable
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|  *	1 - found & usable
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|  *	2 - not found
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|  */
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| static
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| int in_async(unsigned long addr, unsigned long size)
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| {
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| 	if (addr >= ASYNC_BANK0_BASE && addr < ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE) {
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| 		if (!ASYNC_ENABLED(0, 0))
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| 			return 0;
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| 		if (addr + size <= ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE)
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| 			return 1;
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| 		size -= ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE - addr;
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| 		addr = ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE;
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| 	}
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| 	if (addr >= ASYNC_BANK1_BASE && addr < ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE) {
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| 		if (!ASYNC_ENABLED(1, 0))
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| 			return 0;
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| 		if (addr + size <= ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE)
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| 			return 1;
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| 		size -= ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE - addr;
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| 		addr = ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE;
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| 	}
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| 	if (addr >= ASYNC_BANK2_BASE && addr < ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE) {
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| 		if (!ASYNC_ENABLED(2, 1))
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| 			return 0;
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| 		if (addr + size <= ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE)
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| 			return 1;
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| 		size -= ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE - addr;
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| 		addr = ASYNC_BANK2_BASE + ASYNC_BANK2_SIZE;
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| 	}
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| 	if (addr >= ASYNC_BANK3_BASE && addr < ASYNC_BANK3_BASE + ASYNC_BANK3_SIZE) {
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| 		if (ASYNC_ENABLED(3, 1))
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| 			return 0;
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| 		if (addr + size <= ASYNC_BANK3_BASE + ASYNC_BANK3_SIZE)
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| 			return 1;
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| 		return 0;
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| 	}
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| 
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| 	/* not within async bounds */
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| 	return 2;
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| }
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| 
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| int bfin_mem_access_type(unsigned long addr, unsigned long size)
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| {
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| 	int cpu = raw_smp_processor_id();
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| 
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| 	/* Check that things do not wrap around */
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| 	if (addr > ULONG_MAX - size)
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| 		return -EFAULT;
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| 
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| 	if (in_mem(addr, size, FIXED_CODE_START, physical_mem_end))
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| 		return BFIN_MEM_ACCESS_CORE;
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| 
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| 	if (in_mem_const(addr, size, L1_CODE_START, L1_CODE_LENGTH))
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| 		return cpu == 0 ? BFIN_MEM_ACCESS_ITEST : BFIN_MEM_ACCESS_IDMA;
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| 	if (in_mem_const(addr, size, L1_SCRATCH_START, L1_SCRATCH_LENGTH))
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| 		return cpu == 0 ? BFIN_MEM_ACCESS_CORE_ONLY : -EFAULT;
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| 	if (in_mem_const(addr, size, L1_DATA_A_START, L1_DATA_A_LENGTH))
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| 		return cpu == 0 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA;
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| 	if (in_mem_const(addr, size, L1_DATA_B_START, L1_DATA_B_LENGTH))
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| 		return cpu == 0 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA;
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| #ifdef COREB_L1_CODE_START
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| 	if (in_mem_const(addr, size, COREB_L1_CODE_START, COREB_L1_CODE_LENGTH))
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| 		return cpu == 1 ? BFIN_MEM_ACCESS_ITEST : BFIN_MEM_ACCESS_IDMA;
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| 	if (in_mem_const(addr, size, COREB_L1_SCRATCH_START, L1_SCRATCH_LENGTH))
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| 		return cpu == 1 ? BFIN_MEM_ACCESS_CORE_ONLY : -EFAULT;
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| 	if (in_mem_const(addr, size, COREB_L1_DATA_A_START, COREB_L1_DATA_A_LENGTH))
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| 		return cpu == 1 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA;
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| 	if (in_mem_const(addr, size, COREB_L1_DATA_B_START, COREB_L1_DATA_B_LENGTH))
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| 		return cpu == 1 ? BFIN_MEM_ACCESS_CORE : BFIN_MEM_ACCESS_IDMA;
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| #endif
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| 	if (in_mem_const(addr, size, L2_START, L2_LENGTH))
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| 		return BFIN_MEM_ACCESS_CORE;
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| 
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| 	if (addr >= SYSMMR_BASE)
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| 		return BFIN_MEM_ACCESS_CORE_ONLY;
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| 
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| 	switch (in_async(addr, size)) {
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| 	case 0: return -EFAULT;
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| 	case 1: return BFIN_MEM_ACCESS_CORE;
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| 	case 2: /* fall through */;
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| 	}
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| 
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| 	if (in_mem_const(addr, size, BOOT_ROM_START, BOOT_ROM_LENGTH))
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| 		return BFIN_MEM_ACCESS_CORE;
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| 	if (in_mem_const(addr, size, L1_ROM_START, L1_ROM_LENGTH))
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| 		return BFIN_MEM_ACCESS_DMA;
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| 
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| 	return -EFAULT;
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| }
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| 
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| #if defined(CONFIG_ACCESS_CHECK)
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| #ifdef CONFIG_ACCESS_OK_L1
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| __attribute__((l1_text))
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| #endif
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| /* Return 1 if access to memory range is OK, 0 otherwise */
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| int _access_ok(unsigned long addr, unsigned long size)
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| {
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| 	int aret;
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| 
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| 	if (size == 0)
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| 		return 1;
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| 	/* Check that things do not wrap around */
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| 	if (addr > ULONG_MAX - size)
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| 		return 0;
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| 	if (segment_eq(get_fs(), KERNEL_DS))
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| 		return 1;
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| #ifdef CONFIG_MTD_UCLINUX
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| 	if (1)
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| #else
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| 	if (0)
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| #endif
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| 	{
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| 		if (in_mem(addr, size, memory_start, memory_end))
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| 			return 1;
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| 		if (in_mem(addr, size, memory_mtd_end, physical_mem_end))
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| 			return 1;
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| # ifndef CONFIG_ROMFS_ON_MTD
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| 		if (0)
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| # endif
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| 			/* For XIP, allow user space to use pointers within the ROMFS.  */
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| 			if (in_mem(addr, size, memory_mtd_start, memory_mtd_end))
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| 				return 1;
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| 	} else {
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| 		if (in_mem(addr, size, memory_start, physical_mem_end))
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| 			return 1;
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| 	}
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| 
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| 	if (in_mem(addr, size, (unsigned long)__init_begin, (unsigned long)__init_end))
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| 		return 1;
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| 
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| 	if (in_mem_const(addr, size, L1_CODE_START, L1_CODE_LENGTH))
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| 		return 1;
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| 	if (in_mem_const_off(addr, size, _etext_l1 - _stext_l1, L1_CODE_START, L1_CODE_LENGTH))
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| 		return 1;
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| 	if (in_mem_const_off(addr, size, _ebss_l1 - _sdata_l1, L1_DATA_A_START, L1_DATA_A_LENGTH))
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| 		return 1;
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| 	if (in_mem_const_off(addr, size, _ebss_b_l1 - _sdata_b_l1, L1_DATA_B_START, L1_DATA_B_LENGTH))
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| 		return 1;
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| #ifdef COREB_L1_CODE_START
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| 	if (in_mem_const(addr, size, COREB_L1_CODE_START, COREB_L1_CODE_LENGTH))
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| 		return 1;
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| 	if (in_mem_const(addr, size, COREB_L1_SCRATCH_START, L1_SCRATCH_LENGTH))
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| 		return 1;
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| 	if (in_mem_const(addr, size, COREB_L1_DATA_A_START, COREB_L1_DATA_A_LENGTH))
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| 		return 1;
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| 	if (in_mem_const(addr, size, COREB_L1_DATA_B_START, COREB_L1_DATA_B_LENGTH))
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| 		return 1;
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| #endif
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| 
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| #ifndef CONFIG_EXCEPTION_L1_SCRATCH
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| 	if (in_mem_const(addr, size, (unsigned long)l1_stack_base, l1_stack_len))
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| 		return 1;
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| #endif
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| 
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| 	aret = in_async(addr, size);
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| 	if (aret < 2)
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| 		return aret;
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| 
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| 	if (in_mem_const_off(addr, size, _ebss_l2 - _stext_l2, L2_START, L2_LENGTH))
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| 		return 1;
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| 
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| 	if (in_mem_const(addr, size, BOOT_ROM_START, BOOT_ROM_LENGTH))
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| 		return 1;
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| 	if (in_mem_const(addr, size, L1_ROM_START, L1_ROM_LENGTH))
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| 		return 1;
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| 
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| 	return 0;
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| }
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| EXPORT_SYMBOL(_access_ok);
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| #endif /* CONFIG_ACCESS_CHECK */
 |