126 lines
2.9 KiB
C
126 lines
2.9 KiB
C
/*
|
|
* Copyright © 2008 Keith Packard <keithp@keithp.com>
|
|
*
|
|
* This file is free software; you can redistribute it and/or modify
|
|
* it under the terms of version 2 of the GNU General Public License
|
|
* as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software Foundation,
|
|
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*/
|
|
|
|
#ifndef _LINUX_IO_MAPPING_H
|
|
#define _LINUX_IO_MAPPING_H
|
|
|
|
#include <linux/types.h>
|
|
#include <asm/io.h>
|
|
#include <asm/page.h>
|
|
#include <asm/iomap.h>
|
|
|
|
/*
|
|
* The io_mapping mechanism provides an abstraction for mapping
|
|
* individual pages from an io device to the CPU in an efficient fashion.
|
|
*
|
|
* See Documentation/io_mapping.txt
|
|
*/
|
|
|
|
/* this struct isn't actually defined anywhere */
|
|
struct io_mapping;
|
|
|
|
#ifdef CONFIG_HAVE_ATOMIC_IOMAP
|
|
|
|
/*
|
|
* For small address space machines, mapping large objects
|
|
* into the kernel virtual space isn't practical. Where
|
|
* available, use fixmap support to dynamically map pages
|
|
* of the object at run time.
|
|
*/
|
|
|
|
static inline struct io_mapping *
|
|
io_mapping_create_wc(unsigned long base, unsigned long size)
|
|
{
|
|
return (struct io_mapping *) base;
|
|
}
|
|
|
|
static inline void
|
|
io_mapping_free(struct io_mapping *mapping)
|
|
{
|
|
}
|
|
|
|
/* Atomic map/unmap */
|
|
static inline void *
|
|
io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset)
|
|
{
|
|
offset += (unsigned long) mapping;
|
|
return iomap_atomic_prot_pfn(offset >> PAGE_SHIFT, KM_USER0,
|
|
__pgprot(__PAGE_KERNEL_WC));
|
|
}
|
|
|
|
static inline void
|
|
io_mapping_unmap_atomic(void *vaddr)
|
|
{
|
|
iounmap_atomic(vaddr, KM_USER0);
|
|
}
|
|
|
|
static inline void *
|
|
io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset)
|
|
{
|
|
offset += (unsigned long) mapping;
|
|
return ioremap_wc(offset, PAGE_SIZE);
|
|
}
|
|
|
|
static inline void
|
|
io_mapping_unmap(void *vaddr)
|
|
{
|
|
iounmap(vaddr);
|
|
}
|
|
|
|
#else
|
|
|
|
/* Create the io_mapping object*/
|
|
static inline struct io_mapping *
|
|
io_mapping_create_wc(unsigned long base, unsigned long size)
|
|
{
|
|
return (struct io_mapping *) ioremap_wc(base, size);
|
|
}
|
|
|
|
static inline void
|
|
io_mapping_free(struct io_mapping *mapping)
|
|
{
|
|
iounmap(mapping);
|
|
}
|
|
|
|
/* Atomic map/unmap */
|
|
static inline void *
|
|
io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset)
|
|
{
|
|
return ((char *) mapping) + offset;
|
|
}
|
|
|
|
static inline void
|
|
io_mapping_unmap_atomic(void *vaddr)
|
|
{
|
|
}
|
|
|
|
/* Non-atomic map/unmap */
|
|
static inline void *
|
|
io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset)
|
|
{
|
|
return ((char *) mapping) + offset;
|
|
}
|
|
|
|
static inline void
|
|
io_mapping_unmap(void *vaddr)
|
|
{
|
|
}
|
|
|
|
#endif /* HAVE_ATOMIC_IOMAP */
|
|
|
|
#endif /* _LINUX_IO_MAPPING_H */
|