107 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			107 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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|  */
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| 
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| #include <linux/vmalloc.h>
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| #include <linux/init.h>
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| #include <linux/module.h>
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| #include <linux/io.h>
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| #include <linux/mm.h>
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| #include <linux/slab.h>
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| #include <linux/cache.h>
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| 
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| static inline bool arc_uncached_addr_space(phys_addr_t paddr)
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| {
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| 	if (is_isa_arcompact()) {
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| 		if (paddr >= ARC_UNCACHED_ADDR_SPACE)
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| 			return true;
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| 	} else if (paddr >= perip_base && paddr <= perip_end) {
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| 		return true;
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| 	}
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| 
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| 	return false;
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| }
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| 
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| void __iomem *ioremap(phys_addr_t paddr, unsigned long size)
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| {
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| 	phys_addr_t end;
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| 
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| 	/* Don't allow wraparound or zero size */
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| 	end = paddr + size - 1;
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| 	if (!size || (end < paddr))
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| 		return NULL;
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| 
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| 	/*
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| 	 * If the region is h/w uncached, MMU mapping can be elided as optim
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| 	 * The cast to u32 is fine as this region can only be inside 4GB
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| 	 */
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| 	if (arc_uncached_addr_space(paddr))
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| 		return (void __iomem *)(u32)paddr;
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| 
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| 	return ioremap_prot(paddr, size, PAGE_KERNEL_NO_CACHE);
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| }
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| EXPORT_SYMBOL(ioremap);
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| 
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| /*
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|  * ioremap with access flags
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|  * Cache semantics wise it is same as ioremap - "forced" uncached.
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|  * However unlike vanilla ioremap which bypasses ARC MMU for addresses in
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|  * ARC hardware uncached region, this one still goes thru the MMU as caller
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|  * might need finer access control (R/W/X)
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|  */
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| void __iomem *ioremap_prot(phys_addr_t paddr, unsigned long size,
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| 			   unsigned long flags)
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| {
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| 	unsigned long vaddr;
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| 	struct vm_struct *area;
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| 	phys_addr_t off, end;
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| 	pgprot_t prot = __pgprot(flags);
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| 
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| 	/* Don't allow wraparound, zero size */
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| 	end = paddr + size - 1;
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| 	if ((!size) || (end < paddr))
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| 		return NULL;
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| 
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| 	/* An early platform driver might end up here */
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| 	if (!slab_is_available())
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| 		return NULL;
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| 
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| 	/* force uncached */
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| 	prot = pgprot_noncached(prot);
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| 
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| 	/* Mappings have to be page-aligned */
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| 	off = paddr & ~PAGE_MASK;
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| 	paddr &= PAGE_MASK;
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| 	size = PAGE_ALIGN(end + 1) - paddr;
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| 
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| 	/*
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| 	 * Ok, go for it..
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| 	 */
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| 	area = get_vm_area(size, VM_IOREMAP);
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| 	if (!area)
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| 		return NULL;
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| 	area->phys_addr = paddr;
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| 	vaddr = (unsigned long)area->addr;
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| 	if (ioremap_page_range(vaddr, vaddr + size, paddr, prot)) {
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| 		vunmap((void __force *)vaddr);
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| 		return NULL;
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| 	}
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| 	return (void __iomem *)(off + (char __iomem *)vaddr);
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| }
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| EXPORT_SYMBOL(ioremap_prot);
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| 
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| 
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| void iounmap(const void __iomem *addr)
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| {
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| 	/* weird double cast to handle phys_addr_t > 32 bits */
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| 	if (arc_uncached_addr_space((phys_addr_t)(u32)addr))
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| 		return;
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| 
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| 	vfree((void *)(PAGE_MASK & (unsigned long __force)addr));
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| }
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| EXPORT_SYMBOL(iounmap);
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