Skip to content

Commit

Permalink
[PATCH] m68k: Add the generic dma API functions
Browse files Browse the repository at this point in the history
Signed-off-by: Roman Zippel <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
  • Loading branch information
Roman Zippel authored and Linus Torvalds committed Jun 25, 2006
1 parent 3921ee2 commit b035c96
Show file tree
Hide file tree
Showing 6 changed files with 197 additions and 17 deletions.
2 changes: 1 addition & 1 deletion arch/m68k/apollo/Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -2,4 +2,4 @@
# Makefile for Linux arch/m68k/amiga source directory
#

obj-y := config.o dn_ints.o dma.o
obj-y := config.o dn_ints.o
4 changes: 2 additions & 2 deletions arch/m68k/kernel/Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -9,8 +9,8 @@ else
endif
extra-y += vmlinux.lds

obj-y := entry.o process.o traps.o ints.o signal.o ptrace.o \
sys_m68k.o time.o semaphore.o setup.o m68k_ksyms.o
obj-y := entry.o process.o traps.o ints.o dma.o signal.o ptrace.o \
sys_m68k.o time.o semaphore.o setup.o m68k_ksyms.o

obj-$(CONFIG_PCI) += bios32.o
obj-$(CONFIG_MODULES) += module.o
Expand Down
129 changes: 129 additions & 0 deletions arch/m68k/kernel/dma.c
Original file line number Diff line number Diff line change
@@ -0,0 +1,129 @@
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/

#undef DEBUG

#include <linux/dma-mapping.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/vmalloc.h>

#include <asm/pgalloc.h>
#include <asm/scatterlist.h>

void *dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *handle, int flag)
{
struct page *page, **map;
pgprot_t pgprot;
void *addr;
int i, order;

pr_debug("dma_alloc_coherent: %d,%x\n", size, flag);

size = PAGE_ALIGN(size);
order = get_order(size);

page = alloc_pages(flag, order);
if (!page)
return NULL;

*handle = page_to_phys(page);
map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA);
if (!map) {
__free_pages(page, order);
return NULL;
}
split_page(page, order);

order = 1 << order;
size >>= PAGE_SHIFT;
map[0] = page;
for (i = 1; i < size; i++)
map[i] = page + i;
for (; i < order; i++)
__free_page(page + i);
pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
if (CPU_IS_040_OR_060)
pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
else
pgprot_val(pgprot) |= _PAGE_NOCACHE030;
addr = vmap(map, size, flag, pgprot);
kfree(map);

return addr;
}
EXPORT_SYMBOL(dma_alloc_coherent);

void dma_free_coherent(struct device *dev, size_t size,
void *addr, dma_addr_t handle)
{
pr_debug("dma_free_coherent: %p, %x\n", addr, handle);
vfree(addr);
}
EXPORT_SYMBOL(dma_free_coherent);

inline void dma_sync_single_for_device(struct device *dev, dma_addr_t handle, size_t size,
enum dma_data_direction dir)
{
switch (dir) {
case DMA_TO_DEVICE:
cache_push(handle, size);
break;
case DMA_FROM_DEVICE:
cache_clear(handle, size);
break;
default:
if (printk_ratelimit())
printk("dma_sync_single_for_device: unsupported dir %u\n", dir);
break;
}
}
EXPORT_SYMBOL(dma_sync_single_for_device);

void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction dir)
{
int i;

for (i = 0; i < nents; sg++, i++)
dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
}
EXPORT_SYMBOL(dma_sync_sg_for_device);

dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size,
enum dma_data_direction dir)
{
dma_addr_t handle = virt_to_bus(addr);

dma_sync_single_for_device(dev, handle, size, dir);
return handle;
}
EXPORT_SYMBOL(dma_map_single);

dma_addr_t dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir)
{
dma_addr_t handle = page_to_phys(page) + offset;

dma_sync_single_for_device(dev, handle, size, dir);
return handle;
}
EXPORT_SYMBOL(dma_map_page);

int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction dir)
{
int i;

for (i = 0; i < nents; sg++, i++) {
sg->dma_address = page_to_phys(sg->page) + sg->offset;
dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
}
return nents;
}
EXPORT_SYMBOL(dma_map_sg);
8 changes: 4 additions & 4 deletions drivers/scsi/sun3x_esp.c
Original file line number Diff line number Diff line change
Expand Up @@ -332,11 +332,11 @@ static void dma_mmu_get_scsi_sgl (struct NCR_ESP *esp, Scsi_Cmnd *sp)
struct scatterlist *sg = sp->SCp.buffer;

while (sz >= 0) {
sg[sz].dvma_address = dvma_map((unsigned long)page_address(sg[sz].page) +
sg[sz].dma_address = dvma_map((unsigned long)page_address(sg[sz].page) +
sg[sz].offset, sg[sz].length);
sz--;
}
sp->SCp.ptr=(char *)((unsigned long)sp->SCp.buffer->dvma_address);
sp->SCp.ptr=(char *)((unsigned long)sp->SCp.buffer->dma_address);
}

static void dma_mmu_release_scsi_one (struct NCR_ESP *esp, Scsi_Cmnd *sp)
Expand All @@ -350,14 +350,14 @@ static void dma_mmu_release_scsi_sgl (struct NCR_ESP *esp, Scsi_Cmnd *sp)
struct scatterlist *sg = (struct scatterlist *)sp->buffer;

while(sz >= 0) {
dvma_unmap((char *)sg[sz].dvma_address);
dvma_unmap((char *)sg[sz].dma_address);
sz--;
}
}

static void dma_advance_sg (Scsi_Cmnd *sp)
{
sp->SCp.ptr = (char *)((unsigned long)sp->SCp.buffer->dvma_address);
sp->SCp.ptr = (char *)((unsigned long)sp->SCp.buffer->dma_address);
}

static int sun3x_esp_release(struct Scsi_Host *instance)
Expand Down
62 changes: 57 additions & 5 deletions include/asm-m68k/dma-mapping.h
Original file line number Diff line number Diff line change
@@ -1,11 +1,63 @@
#ifndef _M68K_DMA_MAPPING_H
#define _M68K_DMA_MAPPING_H

struct scatterlist;

#ifdef CONFIG_PCI
#include <asm-generic/dma-mapping.h>
#else
#include <asm-generic/dma-mapping-broken.h>
#endif
static inline int dma_supported(struct device *dev, u64 mask)
{
return 1;
}

static inline int dma_set_mask(struct device *dev, u64 mask)
{
return 0;
}

extern void *dma_alloc_coherent(struct device *, size_t,
dma_addr_t *, int);
extern void dma_free_coherent(struct device *, size_t,
void *, dma_addr_t);

extern dma_addr_t dma_map_single(struct device *, void *, size_t,
enum dma_data_direction);
static inline void dma_unmap_single(struct device *dev, dma_addr_t addr,
size_t size, enum dma_data_direction dir)
{
}

extern dma_addr_t dma_map_page(struct device *, struct page *,
unsigned long, size_t size,
enum dma_data_direction);
static inline void dma_unmap_page(struct device *dev, dma_addr_t address,
size_t size, enum dma_data_direction dir)
{
}

extern int dma_map_sg(struct device *, struct scatterlist *, int,
enum dma_data_direction);
static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
int nhwentries, enum dma_data_direction dir)
{
}

extern void dma_sync_single_for_device(struct device *, dma_addr_t, size_t,
enum dma_data_direction);
extern void dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
enum dma_data_direction);

static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t handle,
size_t size, enum dma_data_direction dir)
{
}

static inline void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir)
{
}

static inline int dma_mapping_error(dma_addr_t handle)
{
return 0;
}

#endif /* _M68K_DMA_MAPPING_H */
9 changes: 4 additions & 5 deletions include/asm-m68k/scatterlist.h
Original file line number Diff line number Diff line change
Expand Up @@ -2,18 +2,17 @@
#define _M68K_SCATTERLIST_H

struct scatterlist {
/* These two are only valid if ADDRESS member of this
* struct is NULL.
*/
struct page *page;
unsigned int offset;

unsigned int length;

__u32 dvma_address; /* A place to hang host-specific addresses at. */
__u32 dma_address; /* A place to hang host-specific addresses at. */
};

/* This is bogus and should go away. */
#define ISA_DMA_THRESHOLD (0x00ffffff)

#define sg_dma_address(sg) ((sg)->dma_address)
#define sg_dma_len(sg) ((sg)->length)

#endif /* !(_M68K_SCATTERLIST_H) */

0 comments on commit b035c96

Please sign in to comment.