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03df8229a8
Provide phys_to_dma/dma_to_phys helpers, everything else is generic. Signed-off-by: Christoph Hellwig <hch@lst.de> Patchwork: https://patchwork.linux-mips.org/patch/19546/ Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: David Daney <david.daney@cavium.com> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: Tom Bogendoerfer <tsbogend@alpha.franken.de> Cc: Huacai Chen <chenhc@lemote.com> Cc: iommu@lists.linux-foundation.org Cc: linux-mips@linux-mips.org
38 lines
953 B
C
38 lines
953 B
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2006 Ralf Baechle <ralf@linux-mips.org>
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*/
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#include <linux/dma-direct.h>
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#include <asm/ip32/crime.h>
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/*
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* Few notes.
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* 1. CPU sees memory as two chunks: 0-256M@0x0, and the rest @0x40000000+256M
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* 2. PCI sees memory as one big chunk @0x0 (or we could use 0x40000000 for
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* native-endian)
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* 3. All other devices see memory as one big chunk at 0x40000000
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* 4. Non-PCI devices will pass NULL as struct device*
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*
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* Thus we translate differently, depending on device.
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*/
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#define RAM_OFFSET_MASK 0x3fffffffUL
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dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
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{
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dma_addr_t dma_addr = paddr & RAM_OFFSET_MASK;
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if (!dev)
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dma_addr += CRIME_HI_MEM_BASE;
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return dma_addr;
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}
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phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t dma_addr)
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{
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phys_addr_t paddr = dma_addr & RAM_OFFSET_MASK;
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if (dma_addr >= 256*1024*1024)
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paddr += CRIME_HI_MEM_BASE;
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return paddr;
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}
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