mirror of https://gitee.com/openkylin/linux.git
47 lines
1.3 KiB
C
47 lines
1.3 KiB
C
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/*
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* Copyright (C) 2000 David J. Mckay (david.mckay@st.com)
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*
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* May be copied or modified under the terms of the GNU General Public
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* License. See linux/COPYING for more information.
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*
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* Dynamic DMA mapping support.
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*
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* On the overdrive, we can only DMA from memory behind the PCI bus!
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* this means that all DMA'able memory must come from there.
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* this restriction will not apply to later boards.
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*/
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#include <linux/types.h>
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#include <linux/mm.h>
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#include <linux/string.h>
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#include <linux/pci.h>
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#include <asm/io.h>
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void *pci_alloc_consistent(struct pci_dev *hwdev, size_t size,
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dma_addr_t * dma_handle)
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{
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void *ret;
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int gfp = GFP_ATOMIC;
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printk("BUG: pci_alloc_consistent() called - not yet supported\n");
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/* We ALWAYS need DMA memory on the overdrive hardware,
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* due to it's extreme weirdness
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* Need to flush the cache here as well, since the memory
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* can still be seen through the cache!
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*/
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gfp |= GFP_DMA;
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ret = (void *) __get_free_pages(gfp, get_order(size));
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if (ret != NULL) {
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memset(ret, 0, size);
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*dma_handle = virt_to_bus(ret);
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}
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return ret;
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}
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void pci_free_consistent(struct pci_dev *hwdev, size_t size,
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void *vaddr, dma_addr_t dma_handle)
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{
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free_pages((unsigned long) vaddr, get_order(size));
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}
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