6a5c7be5e4
The hook dma_get_required_mask is supposed to return the mask required by the platform to operate efficently. The generic version of dma_get_required_mask in driver/base/platform.c returns a mask based only on max_pfn. However, this is likely too big for iommu systems and could be too small for platforms that require a dma offset or have a secondary window at a high offset. Override the default, provide a hook in ppc_md used by pseries lpar and cell, and provide the default answer based on memblock_end_of_DRAM(), with hooks for get_dma_offset, and provide an implementation for iommu that looks at the defined table size. Coverting from the end address to the required bit mask is based on the generic implementation. The need for this was discovered when the qla2xxx driver switched to 64 bit dma then reverted to 32 bit when dma_get_required_mask said 32 bits was sufficient. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org Cc: benh@kernel.crashing.org Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> |
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| boot | ||
| configs | ||
| include/asm | ||
| kernel | ||
| kvm | ||
| lib | ||
| math-emu | ||
| mm | ||
| net | ||
| oprofile | ||
| platforms | ||
| sysdev | ||
| xmon | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||
| relocs_check.pl | ||