 7cb3be0a27
			
		
	
	
	7cb3be0a27
	
	
	
		
			
			Commit 2ba85e7af4 (ARM: Fix FIQ code on VIVT CPUs) causes the following build warning:
arch/arm/kernel/fiq.c:92:3: warning: passing argument 1 of 'cpu_cache.coherent_kern_range' makes integer from pointer without a cast [enabled by default]
Cast it as '(unsigned long)base' to avoid the warning.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
		
	
			
		
			
				
	
	
		
			155 lines
		
	
	
	
		
			3.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			155 lines
		
	
	
	
		
			3.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *  linux/arch/arm/kernel/fiq.c
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|  *
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|  *  Copyright (C) 1998 Russell King
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|  *  Copyright (C) 1998, 1999 Phil Blundell
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|  *
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|  *  FIQ support written by Philip Blundell <philb@gnu.org>, 1998.
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|  *
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|  *  FIQ support re-written by Russell King to be more generic
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|  *
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|  * We now properly support a method by which the FIQ handlers can
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|  * be stacked onto the vector.  We still do not support sharing
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|  * the FIQ vector itself.
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|  *
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|  * Operation is as follows:
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|  *  1. Owner A claims FIQ:
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|  *     - default_fiq relinquishes control.
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|  *  2. Owner A:
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|  *     - inserts code.
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|  *     - sets any registers,
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|  *     - enables FIQ.
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|  *  3. Owner B claims FIQ:
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|  *     - if owner A has a relinquish function.
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|  *       - disable FIQs.
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|  *       - saves any registers.
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|  *       - returns zero.
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|  *  4. Owner B:
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|  *     - inserts code.
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|  *     - sets any registers,
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|  *     - enables FIQ.
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|  *  5. Owner B releases FIQ:
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|  *     - Owner A is asked to reacquire FIQ:
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|  *	 - inserts code.
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|  *	 - restores saved registers.
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|  *	 - enables FIQ.
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|  *  6. Goto 3
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|  */
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| #include <linux/module.h>
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| #include <linux/kernel.h>
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| #include <linux/init.h>
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| #include <linux/interrupt.h>
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| #include <linux/seq_file.h>
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| 
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| #include <asm/cacheflush.h>
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| #include <asm/cp15.h>
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| #include <asm/fiq.h>
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| #include <asm/irq.h>
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| #include <asm/traps.h>
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| 
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| #define FIQ_OFFSET ({					\
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| 		extern void *vector_fiq_offset;		\
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| 		(unsigned)&vector_fiq_offset;		\
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| 	})
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| 
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| static unsigned long no_fiq_insn;
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| 
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| /* Default reacquire function
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|  * - we always relinquish FIQ control
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|  * - we always reacquire FIQ control
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|  */
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| static int fiq_def_op(void *ref, int relinquish)
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| {
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| 	if (!relinquish)
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| 		set_fiq_handler(&no_fiq_insn, sizeof(no_fiq_insn));
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| 
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| 	return 0;
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| }
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| 
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| static struct fiq_handler default_owner = {
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| 	.name	= "default",
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| 	.fiq_op = fiq_def_op,
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| };
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| 
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| static struct fiq_handler *current_fiq = &default_owner;
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| 
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| int show_fiq_list(struct seq_file *p, int prec)
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| {
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| 	if (current_fiq != &default_owner)
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| 		seq_printf(p, "%*s:              %s\n", prec, "FIQ",
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| 			current_fiq->name);
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| 
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| 	return 0;
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| }
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| 
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| void set_fiq_handler(void *start, unsigned int length)
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| {
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| 	void *base = vectors_page;
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| 	unsigned offset = FIQ_OFFSET;
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| 
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| 	memcpy(base + offset, start, length);
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| 	if (!cache_is_vipt_nonaliasing())
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| 		flush_icache_range((unsigned long)base + offset, offset +
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| 				   length);
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| 	flush_icache_range(0xffff0000 + offset, 0xffff0000 + offset + length);
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| }
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| 
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| int claim_fiq(struct fiq_handler *f)
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| {
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| 	int ret = 0;
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| 
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| 	if (current_fiq) {
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| 		ret = -EBUSY;
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| 
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| 		if (current_fiq->fiq_op != NULL)
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| 			ret = current_fiq->fiq_op(current_fiq->dev_id, 1);
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| 	}
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| 
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| 	if (!ret) {
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| 		f->next = current_fiq;
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| 		current_fiq = f;
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| 	}
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| 
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| 	return ret;
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| }
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| 
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| void release_fiq(struct fiq_handler *f)
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| {
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| 	if (current_fiq != f) {
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| 		printk(KERN_ERR "%s FIQ trying to release %s FIQ\n",
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| 		       f->name, current_fiq->name);
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| 		dump_stack();
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| 		return;
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| 	}
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| 
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| 	do
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| 		current_fiq = current_fiq->next;
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| 	while (current_fiq->fiq_op(current_fiq->dev_id, 0));
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| }
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| 
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| static int fiq_start;
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| 
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| void enable_fiq(int fiq)
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| {
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| 	enable_irq(fiq + fiq_start);
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| }
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| 
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| void disable_fiq(int fiq)
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| {
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| 	disable_irq(fiq + fiq_start);
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| }
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| 
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| EXPORT_SYMBOL(set_fiq_handler);
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| EXPORT_SYMBOL(__set_fiq_regs);	/* defined in fiqasm.S */
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| EXPORT_SYMBOL(__get_fiq_regs);	/* defined in fiqasm.S */
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| EXPORT_SYMBOL(claim_fiq);
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| EXPORT_SYMBOL(release_fiq);
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| EXPORT_SYMBOL(enable_fiq);
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| EXPORT_SYMBOL(disable_fiq);
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| 
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| void __init init_FIQ(int start)
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| {
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| 	unsigned offset = FIQ_OFFSET;
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| 	no_fiq_insn = *(unsigned long *)(0xffff0000 + offset);
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| 	fiq_start = start;
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| }
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