projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* |
| 2 | * Support for DMA from PCI devices to main memory on | |
| 3 | * machines without an iommu or with directly addressable | |
| 4 | * RAM (typically a pmac with 2Gb of RAM or less) | |
| 5 | * | |
| 6 | * Copyright (C) 2003 Benjamin Herrenschmidt (benh@kernel.crashing.org) | |
| 7 | * | |
| 8 | * This program is free software; you can redistribute it and/or | |
| 9 | * modify it under the terms of the GNU General Public License | |
| 10 | * as published by the Free Software Foundation; either version | |
| 11 | * 2 of the License, or (at your option) any later version. | |
| 12 | */ | |
| 13 | ||
| 14 | #include <linux/kernel.h> | |
| 15 | #include <linux/pci.h> | |
| 16 | #include <linux/delay.h> | |
| 17 | #include <linux/string.h> | |
| 18 | #include <linux/init.h> | |
| 19 | #include <linux/bootmem.h> | |
| 20 | #include <linux/mm.h> | |
| 21 | #include <linux/dma-mapping.h> | |
| 22 | ||
| 23 | #include <asm/sections.h> | |
| 24 | #include <asm/io.h> | |
| 25 | #include <asm/prom.h> | |
| 26 | #include <asm/pci-bridge.h> | |
| 27 | #include <asm/machdep.h> | |
| 28 | #include <asm/pmac_feature.h> | |
| 29 | #include <asm/abs_addr.h> | |
| 30 | ||
| 31 | #include "pci.h" | |
| 32 | ||
| 33 | static void *pci_direct_alloc_coherent(struct device *hwdev, size_t size, | |
| dd0fc66f | 34 | dma_addr_t *dma_handle, gfp_t flag) |
| 1da177e4 LT |
35 | { |
| 36 | void *ret; | |
| 37 | ||
| 38 | ret = (void *)__get_free_pages(flag, get_order(size)); | |
| 39 | if (ret != NULL) { | |
| 40 | memset(ret, 0, size); | |
| 41 | *dma_handle = virt_to_abs(ret); | |
| 42 | } | |
| 43 | return ret; | |
| 44 | } | |
| 45 | ||
| 46 | static void pci_direct_free_coherent(struct device *hwdev, size_t size, | |
| 47 | void *vaddr, dma_addr_t dma_handle) | |
| 48 | { | |
| 49 | free_pages((unsigned long)vaddr, get_order(size)); | |
| 50 | } | |
| 51 | ||
| 52 | static dma_addr_t pci_direct_map_single(struct device *hwdev, void *ptr, | |
| 53 | size_t size, enum dma_data_direction direction) | |
| 54 | { | |
| 55 | return virt_to_abs(ptr); | |
| 56 | } | |
| 57 | ||
| 58 | static void pci_direct_unmap_single(struct device *hwdev, dma_addr_t dma_addr, | |
| 59 | size_t size, enum dma_data_direction direction) | |
| 60 | { | |
| 61 | } | |
| 62 | ||
| 63 | static int pci_direct_map_sg(struct device *hwdev, struct scatterlist *sg, | |
| 64 | int nents, enum dma_data_direction direction) | |
| 65 | { | |
| 66 | int i; | |
| 67 | ||
| 68 | for (i = 0; i < nents; i++, sg++) { | |
| 69 | sg->dma_address = page_to_phys(sg->page) + sg->offset; | |
| 70 | sg->dma_length = sg->length; | |
| 71 | } | |
| 72 | ||
| 73 | return nents; | |
| 74 | } | |
| 75 | ||
| 76 | static void pci_direct_unmap_sg(struct device *hwdev, struct scatterlist *sg, | |
| 77 | int nents, enum dma_data_direction direction) | |
| 78 | { | |
| 79 | } | |
| 80 | ||
| 81 | static int pci_direct_dma_supported(struct device *dev, u64 mask) | |
| 82 | { | |
| 83 | return mask < 0x100000000ull; | |
| 84 | } | |
| 85 | ||
| 86 | void __init pci_direct_iommu_init(void) | |
| 87 | { | |
| 88 | pci_dma_ops.alloc_coherent = pci_direct_alloc_coherent; | |
| 89 | pci_dma_ops.free_coherent = pci_direct_free_coherent; | |
| 90 | pci_dma_ops.map_single = pci_direct_map_single; | |
| 91 | pci_dma_ops.unmap_single = pci_direct_unmap_single; | |
| 92 | pci_dma_ops.map_sg = pci_direct_map_sg; | |
| 93 | pci_dma_ops.unmap_sg = pci_direct_unmap_sg; | |
| 94 | pci_dma_ops.dma_supported = pci_direct_dma_supported; | |
| 95 | } |