1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
96 lines
2.5 KiB
C
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, unsigned int __nocast 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;
|
|
}
|