kernel-ark/include/linux/io-mapping.h
Linus Torvalds 37be944a02 Merge branch 'drm-core-next' of git://people.freedesktop.org/~airlied/linux
* 'drm-core-next' of git://people.freedesktop.org/~airlied/linux: (290 commits)
  Revert "drm/ttm: add a way to bo_wait for either the last read or last write"
  Revert "drm/radeon/kms: add a new gem_wait ioctl with read/write flags"
  vmwgfx: Don't pass unused arguments to do_dirty functions
  vmwgfx: Emulate depth 32 framebuffers
  drm/radeon: Lower the severity of the radeon lockup messages.
  drm/i915/dp: Fix eDP on PCH DP on CPT/PPT
  drm/i915/dp: Introduce is_cpu_edp()
  drm/i915: use correct SPD type value
  drm/i915: fix ILK+ infoframe support
  drm/i915: add DP test request handling
  drm/i915: read full receiver capability field during DP hot plug
  drm/i915/dp: Remove eDP special cases from bandwidth checks
  drm/i915/dp: Fix the math in intel_dp_link_required
  drm/i915/panel: Always record the backlight level again (but cleverly)
  i915: Move i915_read/write out of line
  drm/i915: remove transcoder PLL mashing from mode_set per specs
  drm/i915: if transcoder disable fails, say which
  drm/i915: set watermarks for third pipe on IVB
  drm/i915: export a CPT mode set verification function
  drm/i915: fix transcoder PLL select masking
  ...
2011-10-28 05:54:23 -07:00

168 lines
3.6 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 <linux/slab.h>
#include <asm/io.h>
#include <asm/page.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
*/
#ifdef CONFIG_HAVE_ATOMIC_IOMAP
#include <asm/iomap.h>
struct io_mapping {
resource_size_t base;
unsigned long size;
pgprot_t prot;
};
/*
* 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(resource_size_t base, unsigned long size)
{
struct io_mapping *iomap;
pgprot_t prot;
iomap = kmalloc(sizeof(*iomap), GFP_KERNEL);
if (!iomap)
goto out_err;
if (iomap_create_wc(base, size, &prot))
goto out_free;
iomap->base = base;
iomap->size = size;
iomap->prot = prot;
return iomap;
out_free:
kfree(iomap);
out_err:
return NULL;
}
static inline void
io_mapping_free(struct io_mapping *mapping)
{
iomap_free(mapping->base, mapping->size);
kfree(mapping);
}
/* Atomic map/unmap */
static inline void __iomem *
io_mapping_map_atomic_wc(struct io_mapping *mapping,
unsigned long offset)
{
resource_size_t phys_addr;
unsigned long pfn;
BUG_ON(offset >= mapping->size);
phys_addr = mapping->base + offset;
pfn = (unsigned long) (phys_addr >> PAGE_SHIFT);
return iomap_atomic_prot_pfn(pfn, mapping->prot);
}
static inline void
io_mapping_unmap_atomic(void __iomem *vaddr)
{
iounmap_atomic(vaddr);
}
static inline void __iomem *
io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset)
{
resource_size_t phys_addr;
BUG_ON(offset >= mapping->size);
phys_addr = mapping->base + offset;
return ioremap_wc(phys_addr, PAGE_SIZE);
}
static inline void
io_mapping_unmap(void __iomem *vaddr)
{
iounmap(vaddr);
}
#else
#include <linux/uaccess.h>
/* this struct isn't actually defined anywhere */
struct io_mapping;
/* Create the io_mapping object*/
static inline struct io_mapping *
io_mapping_create_wc(resource_size_t base, unsigned long size)
{
return (struct io_mapping __force *) ioremap_wc(base, size);
}
static inline void
io_mapping_free(struct io_mapping *mapping)
{
iounmap((void __force __iomem *) mapping);
}
/* Atomic map/unmap */
static inline void __iomem *
io_mapping_map_atomic_wc(struct io_mapping *mapping,
unsigned long offset)
{
pagefault_disable();
return ((char __force __iomem *) mapping) + offset;
}
static inline void
io_mapping_unmap_atomic(void __iomem *vaddr)
{
pagefault_enable();
}
/* Non-atomic map/unmap */
static inline void __iomem *
io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset)
{
return ((char __force __iomem *) mapping) + offset;
}
static inline void
io_mapping_unmap(void __iomem *vaddr)
{
}
#endif /* HAVE_ATOMIC_IOMAP */
#endif /* _LINUX_IO_MAPPING_H */