alistair23-linux/arch/powerpc/include/asm/iommu.h
Mark Nelson f9226d572d powerpc: Update remaining dma_mapping_ops to use map/unmap_page
After the merge of the 32 and 64bit DMA code, dma_direct_ops lost
their map/unmap_single() functions but gained map/unmap_page().  This
caused a problem for Cell because Cell's dma_iommu_fixed_ops called
the dma_direct_ops if the fixed linear mapping was to be used or the
iommu ops if the dynamic window was to be used.  So in order to fix
this problem we need to update the 64bit DMA code to use
map/unmap_page.

First, we update the generic IOMMU code so that iommu_map_single()
becomes iommu_map_page() and iommu_unmap_single() becomes
iommu_unmap_page().  Then we propagate these changes up through all
the callers of these two functions and in the process update all the
dma_mapping_ops so that they have map/unmap_page rahter than
map/unmap_single.  We can do this because on 64bit there is no HIGHMEM
memory so map/unmap_page ends up performing exactly the same function
as map/unmap_single, just taking different arguments.

This has no affect on drivers because the dma_map_single_attrs() just
ends up calling the map_page() function of the appropriate
dma_mapping_ops and similarly the dma_unmap_single_attrs() calls
unmap_page().

This fixes an oops on Cell blades, which oops on boot without this
because they call dma_direct_ops.map_single, which is NULL.

Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-10-31 16:13:48 +11:00

133 lines
4.5 KiB
C

/*
* Copyright (C) 2001 Mike Corrigan & Dave Engebretsen, IBM Corporation
* Rewrite, cleanup:
* Copyright (C) 2004 Olof Johansson <olof@lixom.net>, IBM Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _ASM_IOMMU_H
#define _ASM_IOMMU_H
#ifdef __KERNEL__
#include <linux/compiler.h>
#include <linux/spinlock.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/bitops.h>
#include <asm/machdep.h>
#include <asm/types.h>
#define IOMMU_PAGE_SHIFT 12
#define IOMMU_PAGE_SIZE (ASM_CONST(1) << IOMMU_PAGE_SHIFT)
#define IOMMU_PAGE_MASK (~((1 << IOMMU_PAGE_SHIFT) - 1))
#define IOMMU_PAGE_ALIGN(addr) _ALIGN_UP(addr, IOMMU_PAGE_SIZE)
/* Boot time flags */
extern int iommu_is_off;
extern int iommu_force_on;
/* Pure 2^n version of get_order */
static __inline__ __attribute_const__ int get_iommu_order(unsigned long size)
{
return __ilog2((size - 1) >> IOMMU_PAGE_SHIFT) + 1;
}
/*
* IOMAP_MAX_ORDER defines the largest contiguous block
* of dma space we can get. IOMAP_MAX_ORDER = 13
* allows up to 2**12 pages (4096 * 4096) = 16 MB
*/
#define IOMAP_MAX_ORDER 13
struct iommu_table {
unsigned long it_busno; /* Bus number this table belongs to */
unsigned long it_size; /* Size of iommu table in entries */
unsigned long it_offset; /* Offset into global table */
unsigned long it_base; /* mapped address of tce table */
unsigned long it_index; /* which iommu table this is */
unsigned long it_type; /* type: PCI or Virtual Bus */
unsigned long it_blocksize; /* Entries in each block (cacheline) */
unsigned long it_hint; /* Hint for next alloc */
unsigned long it_largehint; /* Hint for large allocs */
unsigned long it_halfpoint; /* Breaking point for small/large allocs */
spinlock_t it_lock; /* Protects it_map */
unsigned long *it_map; /* A simple allocation bitmap for now */
};
struct scatterlist;
/* Frees table for an individual device node */
extern void iommu_free_table(struct iommu_table *tbl, const char *node_name);
/* Initializes an iommu_table based in values set in the passed-in
* structure
*/
extern struct iommu_table *iommu_init_table(struct iommu_table * tbl,
int nid);
extern int iommu_map_sg(struct device *dev, struct iommu_table *tbl,
struct scatterlist *sglist, int nelems,
unsigned long mask, enum dma_data_direction direction,
struct dma_attrs *attrs);
extern void iommu_unmap_sg(struct iommu_table *tbl, struct scatterlist *sglist,
int nelems, enum dma_data_direction direction,
struct dma_attrs *attrs);
extern void *iommu_alloc_coherent(struct device *dev, struct iommu_table *tbl,
size_t size, dma_addr_t *dma_handle,
unsigned long mask, gfp_t flag, int node);
extern void iommu_free_coherent(struct iommu_table *tbl, size_t size,
void *vaddr, dma_addr_t dma_handle);
extern dma_addr_t iommu_map_page(struct device *dev, struct iommu_table *tbl,
struct page *page, unsigned long offset,
size_t size, unsigned long mask,
enum dma_data_direction direction,
struct dma_attrs *attrs);
extern void iommu_unmap_page(struct iommu_table *tbl, dma_addr_t dma_handle,
size_t size, enum dma_data_direction direction,
struct dma_attrs *attrs);
extern void iommu_init_early_pSeries(void);
extern void iommu_init_early_iSeries(void);
extern void iommu_init_early_dart(void);
extern void iommu_init_early_pasemi(void);
#ifdef CONFIG_PCI
extern void pci_iommu_init(void);
extern void pci_direct_iommu_init(void);
#else
static inline void pci_iommu_init(void) { }
#endif
extern void alloc_dart_table(void);
#if defined(CONFIG_PPC64) && defined(CONFIG_PM)
static inline void iommu_save(void)
{
if (ppc_md.iommu_save)
ppc_md.iommu_save();
}
static inline void iommu_restore(void)
{
if (ppc_md.iommu_restore)
ppc_md.iommu_restore();
}
#endif
#endif /* __KERNEL__ */
#endif /* _ASM_IOMMU_H */