projects / mirror_ubuntu-bionic-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| b920de1b DH |
1 | /* MN10300 Dynamic DMA mapping support |
| 2 | * | |
| 3 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. | |
| 4 | * Written by David Howells (dhowells@redhat.com) | |
| 5 | * Derived from: arch/i386/kernel/pci-dma.c | |
| 6 | * | |
| 7 | * This program is free software; you can redistribute it and/or | |
| 8 | * modify it under the terms of the GNU General Public Licence | |
| 9 | * as published by the Free Software Foundation; either version | |
| 10 | * 2 of the Licence, or (at your option) any later version. | |
| 11 | */ | |
| 12 | ||
| 13 | #include <linux/types.h> | |
| 14 | #include <linux/mm.h> | |
| 15 | #include <linux/string.h> | |
| 16 | #include <linux/pci.h> | |
| 17 | #include <asm/io.h> | |
| 18 | ||
| 19 | void *dma_alloc_coherent(struct device *dev, size_t size, | |
| 20 | dma_addr_t *dma_handle, int gfp) | |
| 21 | { | |
| 22 | unsigned long addr; | |
| 23 | void *ret; | |
| 24 | ||
| 25 | /* ignore region specifiers */ | |
| 26 | gfp &= ~(__GFP_DMA | __GFP_HIGHMEM); | |
| 27 | ||
| 28 | if (dev == NULL || dev->coherent_dma_mask < 0xffffffff) | |
| 29 | gfp |= GFP_DMA; | |
| 30 | ||
| 31 | addr = __get_free_pages(gfp, get_order(size)); | |
| 32 | if (!addr) | |
| 33 | return NULL; | |
| 34 | ||
| 35 | /* map the coherent memory through the uncached memory window */ | |
| 36 | ret = (void *) (addr | 0x20000000); | |
| 37 | ||
| 38 | /* fill the memory with obvious rubbish */ | |
| 39 | memset((void *) addr, 0xfb, size); | |
| 40 | ||
| 41 | /* write back and evict all cache lines covering this region */ | |
| 42 | mn10300_dcache_flush_inv_range2(virt_to_phys((void *) addr), PAGE_SIZE); | |
| 43 | ||
| 44 | *dma_handle = virt_to_bus((void *) addr); | |
| 45 | return ret; | |
| 46 | } | |
| 47 | EXPORT_SYMBOL(dma_alloc_coherent); | |
| 48 | ||
| 49 | void dma_free_coherent(struct device *dev, size_t size, void *vaddr, | |
| 50 | dma_addr_t dma_handle) | |
| 51 | { | |
| 52 | unsigned long addr = (unsigned long) vaddr & ~0x20000000; | |
| 53 | ||
| 54 | free_pages(addr, get_order(size)); | |
| 55 | } | |
| 56 | EXPORT_SYMBOL(dma_free_coherent); |