linux/arch/ppc64/kernel/pci_direct_iommu.c
Al Viro dd0fc66fb3 [PATCH] gfp flags annotations - part 1
- added typedef unsigned int __nocast gfp_t;

 - replaced __nocast uses for gfp flags with gfp_t - it gives exactly
   the same warnings as far as sparse is concerned, doesn't change
   generated code (from gcc point of view we replaced unsigned int with
   typedef) and documents what's going on far better.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-08 15:00:57 -07:00

96 lines
2.5 KiB
C

/*
* Support for DMA from PCI devices to main memory on
* machines without an iommu or with directly addressable
* RAM (typically a pmac with 2Gb of RAM or less)
*
* Copyright (C) 2003 Benjamin Herrenschmidt (benh@kernel.crashing.org)
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/abs_addr.h>
#include "pci.h"
static void *pci_direct_alloc_coherent(struct device *hwdev, size_t size,
dma_addr_t *dma_handle, gfp_t flag)
{
void *ret;
ret = (void *)__get_free_pages(flag, get_order(size));
if (ret != NULL) {
memset(ret, 0, size);
*dma_handle = virt_to_abs(ret);
}
return ret;
}
static void pci_direct_free_coherent(struct device *hwdev, size_t size,
void *vaddr, dma_addr_t dma_handle)
{
free_pages((unsigned long)vaddr, get_order(size));
}
static dma_addr_t pci_direct_map_single(struct device *hwdev, void *ptr,
size_t size, enum dma_data_direction direction)
{
return virt_to_abs(ptr);
}
static void pci_direct_unmap_single(struct device *hwdev, dma_addr_t dma_addr,
size_t size, enum dma_data_direction direction)
{
}
static int pci_direct_map_sg(struct device *hwdev, struct scatterlist *sg,
int nents, enum dma_data_direction direction)
{
int i;
for (i = 0; i < nents; i++, sg++) {
sg->dma_address = page_to_phys(sg->page) + sg->offset;
sg->dma_length = sg->length;
}
return nents;
}
static void pci_direct_unmap_sg(struct device *hwdev, struct scatterlist *sg,
int nents, enum dma_data_direction direction)
{
}
static int pci_direct_dma_supported(struct device *dev, u64 mask)
{
return mask < 0x100000000ull;
}
void __init pci_direct_iommu_init(void)
{
pci_dma_ops.alloc_coherent = pci_direct_alloc_coherent;
pci_dma_ops.free_coherent = pci_direct_free_coherent;
pci_dma_ops.map_single = pci_direct_map_single;
pci_dma_ops.unmap_single = pci_direct_unmap_single;
pci_dma_ops.map_sg = pci_direct_map_sg;
pci_dma_ops.unmap_sg = pci_direct_unmap_sg;
pci_dma_ops.dma_supported = pci_direct_dma_supported;
}