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2009-05-27powerpc: Move dma-noncoherent.c from arch/powerpc/lib to arch/powerpc/mmBenjamin Herrenschmidt
(pre-requisite to make the next patches more palatable) Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-05-27Revert "powerpc: Rework dma-noncoherent to use generic vmalloc layer"Benjamin Herrenschmidt
This reverts commit 33f00dcedb0e22cdb156a23632814fc580fcfcf8. While it was a good idea to try to use the mm/vmalloc.c allocator instead of our own (in fact, ours is itself a dup on an old variant of the vmalloc one), unfortunately, the approach is terminally busted since dma_alloc_coherent() can be called at interrupt time or in atomic contexts and there's little chances we'll make the code in mm/vmalloc.c cope with\ that :-( Until we can get the generic code to forbid that idiocy and fix all drivers abusing it, we pretty much have no choice but revert to our custom virtual space allocator. There's also a problem with SMP safety since freeing such mapping would require an IPI which cannot be done at interrupt time. However, right now, I don't think we support any platform that is both SMP and has non-coherent DMA (don't laugh, I know such things do exist !) so we can sort that out later. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-23powerpc: Rework dma-noncoherent to use generic vmalloc layerIlya Yanok
This patch rewrites consistent dma allocations support to use vmalloc layer to allocate virtual memory space from vmalloc pool and get rid of CONFIG_CONSISTENT_{START,SIZE}. This greatly simplifies the code by effectively removing a custom allocator we had for virtual space. Signed-off-by: Ilya Yanok <yanok@emcraft.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-12-21powerpc: Rename struct vm_region to avoid conflict with NOMMUDavid Howells
Rename PowerPC's struct vm_region so that I can introduce my own global version for NOMMU. It's feasible that the PowerPC version may wish to use my global one instead. The NOMMU vm_region struct defines areas of the physical memory map that are under mmap. This may include chunks of RAM or regions of memory mapped devices, such as flash. It is also used to retain copies of file content so that shareable private memory mappings of files can be made. As such, it may be compatible with what is described in the banner comment for PowerPC's vm_region struct. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-11-19powerpc: Remove superfluous WARN_ON() from dma-noncoherent.cHollis Blanchard
I can't tell why this WARN_ON exists, and there's no comment explaining it. Whether the pmd is present or not, pte_alloc_kernel() seems to handle both cases. Booting a 440 kernel with 64K PAGE_SIZE triggers the warning, but boot successfully completes and I see no problems beyond that. Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-10-14powerpc: Fix DMA offset for non-coherent DMABenjamin Herrenschmidt
After Becky's work we can almost have different DMA offsets between on-chip devices and PCI. Almost because there's a problem with the non-coherent DMA code that basically ignores the programmed offset to use the global one for everything. This fixes it. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-01powerpc: Prevent memory corruption due to cache invalidation of unaligned ↵Andrew Lewis
DMA buffer On PowerPC processors with non-coherent cache architectures the DMA subsystem calls invalidate_dcache_range() before performing a DMA read operation. If the address and length of the DMA buffer are not aligned to a cache-line boundary this can result in memory outside of the DMA buffer being invalidated in the cache. If this memory has an uncommitted store then the data will be lost and a subsequent read of that address will result in an old value being returned from main memory. Only when the DMA buffer starts on a cache-line boundary and is an exact mutiple of the cache-line size can invalidate_dcache_range() be called, otherwise flush_dcache_range() must be called. flush_dcache_range() will first flush uncommitted writes, and then invalidate the cache. Signed-off-by: Andrew Lewis <andrew-lewis at netspace.net.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-05-08[POWERPC] Remove use of 4level-fixup.h for ppc32David Gibson
For 32-bit systems, powerpc still relies on the 4level-fixup.h hack, to pretend that the generic pagetable handling stuff is 3-levels rather than 4. This patch removes this, instead using the newer pgtable-nopmd.h to handle the elision of both the pud and pmd pagetable levels (ppc32 pagetables are actually 2 levels). This removes a little extraneous code, and makes it more easily compared to the 64-bit pagetable code. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07[POWERPC] 8xx: generic 8xx code arch/powerpc portVitaly Bordug
Including support for non-coherent cache, some mm-related things + relevant field in Kconfig and Makefiles. Also included rheap.o compilation if 8xx is defined. Non-coherent mapping were refined and renamed according to Cristoph Hellwig. Orphaned functions were cleaned up. [Also removed arch/ppc/kernel/dma-mapping.c, because otherwise compiling with ARCH=ppc for a non DMA-cache-coherent platform ends up with two copies of __dma_alloc_coherent etc. -- paulus.] Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com> Signed-off-by: Paul Mackerras <paulus@samba.org>