kernel/arch/powerpc/include/asm/dma-mapping.h, branch linux-4.3.y

dma-mapping: consolidate dma_set_mask

2015-09-10T20:29:01Z

Almost everyone implements dma_set_mask the same way, although some time that's hidden in ->set_dma_mask methods. This patch consolidates those into a common implementation that either calls ->set_dma_mask if present or otherwise uses the default implementation. Some architectures used to only call ->set_dma_mask after the initial checks, and those instance have been fixed to do the full work. h8300 implemented dma_set_mask bogusly as a no-ops and has been fixed. Unfortunately some architectures overload unrelated semantics like changing the dma_ops into it so we still need to allow for an architecture override for now. [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig Cc: Arnd Bergmann Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Yoshinori Sato Cc: Michal Simek Cc: Jonas Bonn Cc: Chris Metcalf Cc: Guan Xuetao Cc: Ralf Baechle Cc: Benjamin Herrenschmidt Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Andy Shevchenko Signed-off-by: Max Filippov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dma-mapping: consolidate dma_supported

2015-09-10T20:29:01Z

Most architectures just call into ->dma_supported, but some also return 1 if the method is not present, or 0 if no dma ops are present (although that should never happeb). Consolidate this more broad version into common code. Also fix h8300 which inorrectly always returned 0, which would have been a problem if it's dma_set_mask implementation wasn't a similarly buggy noop. As a few architectures have much more elaborate implementations, we still allow for arch overrides. [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig Cc: Arnd Bergmann Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Yoshinori Sato Cc: Michal Simek Cc: Jonas Bonn Cc: Chris Metcalf Cc: Guan Xuetao Cc: Ralf Baechle Cc: Benjamin Herrenschmidt Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Andy Shevchenko Signed-off-by: Max Filippov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dma-mapping: cosolidate dma_mapping_error

2015-09-10T20:29:01Z

Currently there are three valid implementations of dma_mapping_error: (1) call ->mapping_error (2) check for a hardcoded error code (3) always return 0 This patch provides a common implementation that calls ->mapping_error if present, then checks for DMA_ERROR_CODE if defined or otherwise returns 0. [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig Cc: Arnd Bergmann Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Yoshinori Sato Cc: Michal Simek Cc: Jonas Bonn Cc: Chris Metcalf Cc: Guan Xuetao Cc: Ralf Baechle Cc: Benjamin Herrenschmidt Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Andy Shevchenko Signed-off-by: Max Filippov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dma-mapping: consolidate dma_{alloc,free}_noncoherent

2015-09-10T20:29:01Z

Most architectures do not support non-coherent allocations and either define dma_{alloc,free}_noncoherent to their coherent versions or stub them out. Openrisc uses dma_{alloc,free}_attrs to implement them, and only Mips implements them directly. This patch moves the Openrisc version to common code, and handles the DMA_ATTR_NON_CONSISTENT case in the mips dma_map_ops instance. Note that actual non-coherent allocations require a dma_cache_sync implementation, so if non-coherent allocations didn't work on an architecture before this patch they still won't work after it. [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig Cc: Arnd Bergmann Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Yoshinori Sato Cc: Michal Simek Cc: Jonas Bonn Cc: Chris Metcalf Cc: Guan Xuetao Cc: Ralf Baechle Cc: Benjamin Herrenschmidt Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Andy Shevchenko Signed-off-by: Max Filippov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dma-mapping: consolidate dma_{alloc,free}_{attrs,coherent}

2015-09-10T20:29:01Z

Since 2009 we have a nice asm-generic header implementing lots of DMA API functions for architectures using struct dma_map_ops, but unfortunately it's still missing a lot of APIs that all architectures still have to duplicate. This series consolidates the remaining functions, although we still need arch opt outs for two of them as a few architectures have very non-standard implementations. This patch (of 5): The coherent DMA allocator works the same over all architectures supporting dma_map operations. This patch consolidates them and converges the minor differences: - the debug_dma helpers are now called from all architectures, including those that were previously missing them - dma_alloc_from_coherent and dma_release_from_coherent are now always called from the generic alloc/free routines instead of the ops dma-mapping-common.h always includes dma-coherent.h to get the defintions for them, or the stubs if the architecture doesn't support this feature - checks for ->alloc / ->free presence are removed. There is only one magic instead of dma_map_ops without them (mic_dma_ops) and that one is x86 only anyway. Besides that only x86 needs special treatment to replace a default devices if none is passed and tweak the gfp_flags. An optional arch hook is provided for that. [linux@roeck-us.net: fix build] [jcmvbkbc@gmail.com: fix xtensa] Signed-off-by: Christoph Hellwig Cc: Arnd Bergmann Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Yoshinori Sato Cc: Michal Simek Cc: Jonas Bonn Cc: Chris Metcalf Cc: Guan Xuetao Cc: Ralf Baechle Cc: Benjamin Herrenschmidt Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Andy Shevchenko Signed-off-by: Guenter Roeck Signed-off-by: Max Filippov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

powerpc/iommu: Support "hybrid" iommu/direct DMA ops for coherent_mask < dma_mask

2015-07-13T00:10:55Z

This patch adds the ability to the DMA direct ops to fallback to the IOMMU ops for coherent alloc/free if the coherent mask of the device isn't suitable for accessing the direct DMA space and the device also happens to have an active IOMMU table. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman

powerpc/iommu: Remove dma_data union

2015-07-13T00:10:54Z

To support "hybrid" DMA ops in a subsequent patch, we will need both a direct DMA offset and an iommu pointer. Those are currently exclusive (a union), so change them to be separate fields. While there, also type iommu_table_base properly and make exist only on CONFIG_PPC64 since it's not referenced on 32-bit at all. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman

powerpc: Use bool function return values of true/false not 1/0

2015-03-31T03:19:47Z

Use the normal return values for bool functions Signed-off-by: Joe Perches Acked-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman

powerpc/powernv: Override dma_get_required_mask()

2014-09-30T07:15:20Z

The dma_get_required_mask() function is used by some drivers to query the platform about what DMA mask is needed to cover all of memory. This is a bit of a strange semantic when we have to choose between IOMMU translation or bypass, but essentially what it means is "what DMA mask will give best performances". Currently, our IOMMU backend always returns a 32-bit mask here, we don't do anything special to it when we have bypass available. This causes some drivers to choose a 32-bit mask, thus losing the ability to use the bypass window, thinking this is more efficient. The problem was reported from the driver of following device: 0004:03:00.0 0107: 1000:0087 (rev 05) 0004:03:00.0 Serial Attached SCSI controller: LSI Logic / Symbios \ Logic SAS2308 PCI-Express Fusion-MPT SAS-2 (rev 05) This patch adds an override of that function in order to, instead, return a 64-bit mask whenever a bypass window is available in order for drivers to prefer this configuration. Reported-by: Murali N. Iyer Suggested-by: Benjamin Herrenschmidt Signed-off-by: Gavin Shan Signed-off-by: Michael Ellerman

powerpc/powernv: Add iommu DMA bypass support for IODA2

2014-02-11T05:07:37Z

This patch adds the support for to create a direct iommu "bypass" window on IODA2 bridges (such as Power8) allowing to bypass iommu page translation completely for 64-bit DMA capable devices, thus significantly improving DMA performances. Additionally, this adds a hook to the struct iommu_table so that the IOMMU API / VFIO can disable the bypass when external ownership is requested, since in that case, the device will be used by an environment such as userspace or a KVM guest which must not be allowed to bypass translations. Signed-off-by: Benjamin Herrenschmidt