diff options
| author | Christoph Hellwig <hch@lst.de> | 2018-06-15 13:08:48 +0200 |
|---|---|---|
| committer | Paul Burton <paul.burton@mips.com> | 2018-06-24 09:27:27 -0700 |
| commit | 03df8229a822ab2c262bf78b05a3ada686b885b9 (patch) | |
| tree | 4dfed8556a62d41e21d2497d9228d1ef829d7ced /arch/mips/sgi-ip32 | |
| parent | e905086e6b2fc9d7e2764cf04622743ca86558f1 (diff) | |
MIPS: IP32: use generic dma noncoherent ops
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
Diffstat (limited to 'arch/mips/sgi-ip32')
| -rw-r--r-- | arch/mips/sgi-ip32/Makefile | 2 | ||||
| -rw-r--r-- | arch/mips/sgi-ip32/ip32-dma.c | 37 |
2 files changed, 38 insertions, 1 deletions
diff --git a/arch/mips/sgi-ip32/Makefile b/arch/mips/sgi-ip32/Makefile index 60f0227425e7..4745cd94df11 100644 --- a/arch/mips/sgi-ip32/Makefile +++ b/arch/mips/sgi-ip32/Makefile @@ -4,4 +4,4 @@ # obj-y += ip32-berr.o ip32-irq.o ip32-platform.o ip32-setup.o ip32-reset.o \ - crime.o ip32-memory.o + crime.o ip32-memory.o ip32-dma.o diff --git a/arch/mips/sgi-ip32/ip32-dma.c b/arch/mips/sgi-ip32/ip32-dma.c new file mode 100644 index 000000000000..fa7b17cb5385 --- /dev/null +++ b/arch/mips/sgi-ip32/ip32-dma.c @@ -0,0 +1,37 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2006 Ralf Baechle <ralf@linux-mips.org> + */ +#include <linux/dma-direct.h> +#include <asm/ip32/crime.h> + +/* + * Few notes. + * 1. CPU sees memory as two chunks: 0-256M@0x0, and the rest @0x40000000+256M + * 2. PCI sees memory as one big chunk @0x0 (or we could use 0x40000000 for + * native-endian) + * 3. All other devices see memory as one big chunk at 0x40000000 + * 4. Non-PCI devices will pass NULL as struct device* + * + * Thus we translate differently, depending on device. + */ + +#define RAM_OFFSET_MASK 0x3fffffffUL + +dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr) +{ + dma_addr_t dma_addr = paddr & RAM_OFFSET_MASK; + + if (!dev) + dma_addr += CRIME_HI_MEM_BASE; + return dma_addr; +} + +phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t dma_addr) +{ + phys_addr_t paddr = dma_addr & RAM_OFFSET_MASK; + + if (dma_addr >= 256*1024*1024) + paddr += CRIME_HI_MEM_BASE; + return paddr; +} |