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| author | Chris Metcalf <cmetcalf@tilera.com> | 2013-08-02 12:24:42 -0400 |
|---|---|---|
| committer | Chris Metcalf <cmetcalf@tilera.com> | 2013-08-06 12:52:33 -0400 |
| commit | 803c874abe1358998ab65a8cca728684ebb50a13 (patch) | |
| tree | 06f6ca14ed84458c0bd2b40e8b61a3cb4c0e8e1c /arch/tile/include/asm | |
| parent | 26cde05a2cb7d4c0f4cd1d4aeeadc2939c972786 (diff) | |
| download | linux-803c874abe1358998ab65a8cca728684ebb50a13.tar.gz linux-803c874abe1358998ab65a8cca728684ebb50a13.tar.bz2 linux-803c874abe1358998ab65a8cca728684ebb50a13.zip | |
tile: support LSI MEGARAID SAS HBA hybrid dma_ops
The LSI MEGARAID SAS HBA suffers from the problem where it can do
64-bit DMA to streaming buffers but not to consistent buffers.
In other words, 64-bit DMA is used for disk data transfers and 32-bit
DMA must be used for control message transfers. According to LSI,
the firmware is not fully functional yet. This change implements a
kind of hybrid dma_ops to support this.
Note that on most other platforms, the 64-bit DMA addressing space is the
same as the 32-bit DMA space and they overlap the physical memory space.
No special arrangement is needed to support this kind of mixed DMA
capability. On TILE-Gx, the 64-bit DMA space is completely separate
from the 32-bit DMA space. Due to the use of the IOMMU, the 64-bit DMA
space doesn't overlap the physical memory space. On the other hand,
the 32-bit DMA space overlaps the physical memory space under 4GB.
The separate address spaces make it necessary to have separate dma_ops.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Diffstat (limited to 'arch/tile/include/asm')
| -rw-r--r-- | arch/tile/include/asm/dma-mapping.h | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/arch/tile/include/asm/dma-mapping.h b/arch/tile/include/asm/dma-mapping.h index f2ff191376b4..4a60059876e6 100644 --- a/arch/tile/include/asm/dma-mapping.h +++ b/arch/tile/include/asm/dma-mapping.h @@ -23,6 +23,7 @@ extern struct dma_map_ops *tile_dma_map_ops; extern struct dma_map_ops *gx_pci_dma_map_ops; extern struct dma_map_ops *gx_legacy_pci_dma_map_ops; +extern struct dma_map_ops *gx_hybrid_pci_dma_map_ops; static inline struct dma_map_ops *get_dma_ops(struct device *dev) { @@ -44,12 +45,12 @@ static inline void set_dma_offset(struct device *dev, dma_addr_t off) static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) { - return paddr + get_dma_offset(dev); + return paddr; } static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr) { - return daddr - get_dma_offset(dev); + return daddr; } static inline void dma_mark_clean(void *addr, size_t size) {} @@ -88,7 +89,10 @@ dma_set_mask(struct device *dev, u64 mask) struct dma_map_ops *dma_ops = get_dma_ops(dev); /* Handle legacy PCI devices with limited memory addressability. */ - if ((dma_ops == gx_pci_dma_map_ops) && (mask <= DMA_BIT_MASK(32))) { + if ((dma_ops == gx_pci_dma_map_ops || + dma_ops == gx_hybrid_pci_dma_map_ops || + dma_ops == gx_legacy_pci_dma_map_ops) && + (mask <= DMA_BIT_MASK(32))) { set_dma_ops(dev, gx_legacy_pci_dma_map_ops); set_dma_offset(dev, 0); if (mask > dev->archdata.max_direct_dma_addr) |