1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2006 Ralf Baechle <ralf@linux-mips.org>
4 */
5 #include <linux/dma-direct.h>
6 #include <asm/ip32/crime.h>
7
8 /*
9 * Few notes.
10 * 1. CPU sees memory as two chunks: 0-256M@0x0, and the rest @0x40000000+256M
11 * 2. PCI sees memory as one big chunk @0x0 (or we could use 0x40000000 for
12 * native-endian)
13 * 3. All other devices see memory as one big chunk at 0x40000000
14 * 4. Non-PCI devices will pass NULL as struct device*
15 *
16 * Thus we translate differently, depending on device.
17 */
18
19 #define RAM_OFFSET_MASK 0x3fffffffUL
20
21 dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
22 {
23 dma_addr_t dma_addr = paddr & RAM_OFFSET_MASK;
24
25 if (!dev)
26 dma_addr += CRIME_HI_MEM_BASE;
27 return dma_addr;
28 }
29
30 phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dma_addr)
31 {
32 phys_addr_t paddr = dma_addr & RAM_OFFSET_MASK;
33
34 if (dma_addr >= 256*1024*1024)
35 paddr += CRIME_HI_MEM_BASE;
36 return paddr;
37 }
38
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