[mirror_ubuntu-bionic-kernel.git] / arch / parisc / mm / ioremap.c

// SPDX-License-Identifier: GPL-2.0
/*
 * arch/parisc/mm/ioremap.c
 *
 * (C) Copyright 1995 1996 Linus Torvalds
 * (C) Copyright 2001-2006 Helge Deller <deller@gmx.de>
 * (C) Copyright 2005 Kyle McMartin <kyle@parisc-linux.org>
 */

#include <linux/vmalloc.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/io.h>
#include <asm/pgalloc.h>

/*
 * Generic mapping function (not visible outside):
 */

/*
 * Remap an arbitrary physical address space into the kernel virtual
 * address space.
 *
 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
 * have to convert them into an offset in a page-aligned mapping, but the
 * caller shouldn't need to know that small detail.
 */
void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
{
	void __iomem *addr;
	struct vm_struct *area;
	unsigned long offset, last_addr;
	pgprot_t pgprot;

#ifdef CONFIG_EISA
	unsigned long end = phys_addr + size - 1;
	/* Support EISA addresses */
	if ((phys_addr >= 0x00080000 && end < 0x000fffff) ||
	    (phys_addr >= 0x00500000 && end < 0x03bfffff)) {
		phys_addr |= F_EXTEND(0xfc000000);
		flags |= _PAGE_NO_CACHE;
	}
#endif

	/* Don't allow wraparound or zero size */
	last_addr = phys_addr + size - 1;
	if (!size || last_addr < phys_addr)
		return NULL;

	/*
	 * Don't allow anybody to remap normal RAM that we're using..
	 */
	if (phys_addr < virt_to_phys(high_memory)) {
		char *t_addr, *t_end;
		struct page *page;

		t_addr = __va(phys_addr);
		t_end = t_addr + (size - 1);
	   
		for (page = virt_to_page(t_addr); 
		     page <= virt_to_page(t_end); page++) {
			if(!PageReserved(page))
				return NULL;
		}
	}

	pgprot = __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY |
			  _PAGE_ACCESSED | flags);

	/*
	 * Mappings have to be page-aligned
	 */
	offset = phys_addr & ~PAGE_MASK;
	phys_addr &= PAGE_MASK;
	size = PAGE_ALIGN(last_addr + 1) - phys_addr;

	/*
	 * Ok, go for it..
	 */
	area = get_vm_area(size, VM_IOREMAP);
	if (!area)
		return NULL;

	addr = (void __iomem *) area->addr;
	if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size,
			       phys_addr, pgprot)) {
		vfree(addr);
		return NULL;
	}

	return (void __iomem *) (offset + (char __iomem *)addr);
}
EXPORT_SYMBOL(__ioremap);

void iounmap(const volatile void __iomem *addr)
{
	if (addr > high_memory)
		return vfree((void *) (PAGE_MASK & (unsigned long __force) addr));
}
EXPORT_SYMBOL(iounmap);
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* arch/parisc/mm/ioremap.c
	4	*
1da177e4	5	* (C) Copyright 1995 1996 Linus Torvalds
b2d6b9fb	6	* (C) Copyright 2001-2006 Helge Deller <deller@gmx.de>
e0565a1c	7	* (C) Copyright 2005 Kyle McMartin <kyle@parisc-linux.org>
1da177e4 LT	8	*/
	9
	10	#include <linux/vmalloc.h>
	11	#include <linux/errno.h>
	12	#include <linux/module.h>
e34067fd	13	#include <linux/io.h>
1da177e4	14	#include <asm/pgalloc.h>
1da177e4	15
1da177e4 LT	16	/*
	17	* Generic mapping function (not visible outside):
	18	*/
	19
	20	/*
	21	* Remap an arbitrary physical address space into the kernel virtual
e0565a1c	22	* address space.
1da177e4 LT	23	*
	24	* NOTE! We need to allow non-page-aligned mappings too: we will obviously
	25	* have to convert them into an offset in a page-aligned mapping, but the
	26	* caller shouldn't need to know that small detail.
	27	*/
	28	void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
	29	{
e51ec241	30	void __iomem *addr;
cb4ab59c HD	31	struct vm_struct *area;
cb4ab59c HD	32	unsigned long offset, last_addr;
e34067fd	33	pgprot_t pgprot;
cb4ab59c	34
29ef8295	35	#ifdef CONFIG_EISA
1da177e4 LT	36	unsigned long end = phys_addr + size - 1;
1da177e4 LT	37	/* Support EISA addresses */
10267cdd HD	38	if ((phys_addr >= 0x00080000 && end < 0x000fffff) \|\|
	39	(phys_addr >= 0x00500000 && end < 0x03bfffff)) {
	40	phys_addr \|= F_EXTEND(0xfc000000);
b2d6b9fb	41	flags \|= _PAGE_NO_CACHE;
1da177e4	42	}
1da177e4 LT	43	#endif
1da177e4 LT	44
1da177e4 LT	45	/* Don't allow wraparound or zero size */
	46	last_addr = phys_addr + size - 1;
	47	if (!size \|\| last_addr < phys_addr)
	48	return NULL;
	49
	50	/*
	51	* Don't allow anybody to remap normal RAM that we're using..
	52	*/
	53	if (phys_addr < virt_to_phys(high_memory)) {
	54	char t_addr, t_end;
	55	struct page *page;
	56
	57	t_addr = __va(phys_addr);
	58	t_end = t_addr + (size - 1);
	59
e0565a1c KM	60	for (page = virt_to_page(t_addr);
e0565a1c KM	61	page <= virt_to_page(t_end); page++) {
1da177e4 LT	62	if(!PageReserved(page))
1da177e4 LT	63	return NULL;
e0565a1c	64	}
1da177e4 LT	65	}
1da177e4 LT	66
e34067fd HS	67	pgprot = __pgprot(_PAGE_PRESENT \| _PAGE_RW \| _PAGE_DIRTY \|
	68	_PAGE_ACCESSED \| flags);
	69
1da177e4 LT	70	/*
	71	* Mappings have to be page-aligned
	72	*/
	73	offset = phys_addr & ~PAGE_MASK;
	74	phys_addr &= PAGE_MASK;
a292dfa0	75	size = PAGE_ALIGN(last_addr + 1) - phys_addr;
1da177e4 LT	76
	77	/*
	78	* Ok, go for it..
	79	*/
	80	area = get_vm_area(size, VM_IOREMAP);
	81	if (!area)
	82	return NULL;
e0565a1c	83
e51ec241	84	addr = (void __iomem *) area->addr;
e34067fd HS	85	if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size,
e34067fd HS	86	phys_addr, pgprot)) {
1da177e4 LT	87	vfree(addr);
	88	return NULL;
	89	}
e0565a1c	90
e51ec241	91	return (void __iomem ) (offset + (char __iomem )addr);
1da177e4	92	}
d345fd36	93	EXPORT_SYMBOL(__ioremap);
1da177e4	94
01232e93	95	void iounmap(const volatile void __iomem *addr)
1da177e4	96	{
1da177e4 LT	97	if (addr > high_memory)
1da177e4 LT	98	return vfree((void *) (PAGE_MASK & (unsigned long __force) addr));
1da177e4	99	}
d345fd36	100	EXPORT_SYMBOL(iounmap);