Commit Graph

63 Commits

Author SHA1 Message Date
Thierry Reding
b4bbb107d7 dma-mapping: Provide write-combine allocations
Provide an implementation for dma_{alloc,free,mmap}_writecombine() when
the architecture supports DMA attributes.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2014-08-26 07:39:13 +02:00
Santosh Shilimkar
812b99e4b0 ARM: dma: implement set_arch_dma_coherent_ops()
Implement the set_arch_dma_coherent_ops() for ARM architecture.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Olof Johansson <olof@lixom.net>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
2014-05-07 09:21:44 -04:00
Grygorii Strashko
6ce0d20016 ARM: dma: Use dma_pfn_offset for dma address translation
In most of cases DMA addresses can be performed using offset value of
 Bus address space relatively to physical address space as following:

PFN->DMA:
 __pfn_to_phys(pfn + [-]dma_pfn_offset)

DMA->PFN:
 __phys_to_pfn(dma_addr) + [-]dma_pfn_offset

Thanks to Russell King for suggesting the optimised macro's for
conversion.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Olof Johansson <olof@lixom.net>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
2014-05-07 09:21:43 -04:00
Linus Torvalds
eda670c626 Features:
- SWIOTLB has tracing added when doing bounce buffer.
  - Xen ARM/ARM64 can use Xen-SWIOTLB. This work allows Linux to
    safely program real devices for DMA operations when running as
    a guest on Xen on ARM, without IOMMU support.*1
  - xen_raw_printk works with PVHVM guests if needed.
 Bug-fixes:
  - Make memory ballooning work under HVM with large MMIO region.
  - Inform hypervisor of MCFG regions found in ACPI DSDT.
  - Remove deprecated IRQF_DISABLED.
  - Remove deprecated __cpuinit.
 
 [*1]:
 "On arm and arm64 all Xen guests, including dom0, run with second stage
 translation enabled. As a consequence when dom0 programs a device for a
 DMA operation is going to use (pseudo) physical addresses instead
 machine addresses. This work introduces two trees to track physical to
 machine and machine to physical mappings of foreign pages. Local pages
 are assumed mapped 1:1 (physical address == machine address).  It
 enables the SWIOTLB-Xen driver on ARM and ARM64, so that Linux can
 translate physical addresses to machine addresses for dma operations
 when necessary. " (Stefano).
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Merge tag 'stable/for-linus-3.13-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen updates from Konrad Rzeszutek Wilk:
 "This has tons of fixes and two major features which are concentrated
  around the Xen SWIOTLB library.

  The short <blurb> is that the tracing facility (just one function) has
  been added to SWIOTLB to make it easier to track I/O progress.
  Additionally under Xen and ARM (32 & 64) the Xen-SWIOTLB driver
  "is used to translate physical to machine and machine to physical
  addresses of foreign[guest] pages for DMA operations" (Stefano) when
  booting under hardware without proper IOMMU.

  There are also bug-fixes, cleanups, compile warning fixes, etc.

  The commit times for some of the commits is a bit fresh - that is b/c
  we wanted to make sure we have the Ack's from the ARM folks - which
  with the string of back-to-back conferences took a bit of time.  Rest
  assured - the code has been stewing in #linux-next for some time.

  Features:
   - SWIOTLB has tracing added when doing bounce buffer.
   - Xen ARM/ARM64 can use Xen-SWIOTLB.  This work allows Linux to
     safely program real devices for DMA operations when running as a
     guest on Xen on ARM, without IOMMU support. [*1]
   - xen_raw_printk works with PVHVM guests if needed.

  Bug-fixes:
   - Make memory ballooning work under HVM with large MMIO region.
   - Inform hypervisor of MCFG regions found in ACPI DSDT.
   - Remove deprecated IRQF_DISABLED.
   - Remove deprecated __cpuinit.

  [*1]:
  "On arm and arm64 all Xen guests, including dom0, run with second
   stage translation enabled.  As a consequence when dom0 programs a
   device for a DMA operation is going to use (pseudo) physical
   addresses instead machine addresses.  This work introduces two trees
   to track physical to machine and machine to physical mappings of
   foreign pages.  Local pages are assumed mapped 1:1 (physical address
   == machine address).  It enables the SWIOTLB-Xen driver on ARM and
   ARM64, so that Linux can translate physical addresses to machine
   addresses for dma operations when necessary.  " (Stefano)"

* tag 'stable/for-linus-3.13-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (32 commits)
  xen/arm: pfn_to_mfn and mfn_to_pfn return the argument if nothing is in the p2m
  arm,arm64/include/asm/io.h: define struct bio_vec
  swiotlb-xen: missing include dma-direction.h
  pci-swiotlb-xen: call pci_request_acs only ifdef CONFIG_PCI
  arm: make SWIOTLB available
  xen: delete new instances of added __cpuinit
  xen/balloon: Set balloon's initial state to number of existing RAM pages
  xen/mcfg: Call PHYSDEVOP_pci_mmcfg_reserved for MCFG areas.
  xen: remove deprecated IRQF_DISABLED
  x86/xen: remove deprecated IRQF_DISABLED
  swiotlb-xen: fix error code returned by xen_swiotlb_map_sg_attrs
  swiotlb-xen: static inline xen_phys_to_bus, xen_bus_to_phys, xen_virt_to_bus and range_straddles_page_boundary
  grant-table: call set_phys_to_machine after mapping grant refs
  arm,arm64: do not always merge biovec if we are running on Xen
  swiotlb: print a warning when the swiotlb is full
  swiotlb-xen: use xen_dma_map/unmap_page, xen_dma_sync_single_for_cpu/device
  xen: introduce xen_dma_map/unmap_page and xen_dma_sync_single_for_cpu/device
  tracing/events: Fix swiotlb tracepoint creation
  swiotlb-xen: use xen_alloc/free_coherent_pages
  xen: introduce xen_alloc/free_coherent_pages
  ...
2013-11-15 13:34:37 +09:00
Konrad Rzeszutek Wilk
e1d8f62ad4 Merge remote-tracking branch 'stefano/swiotlb-xen-9.1' into stable/for-linus-3.13
* stefano/swiotlb-xen-9.1:
  swiotlb-xen: fix error code returned by xen_swiotlb_map_sg_attrs
  swiotlb-xen: static inline xen_phys_to_bus, xen_bus_to_phys, xen_virt_to_bus and range_straddles_page_boundary
  grant-table: call set_phys_to_machine after mapping grant refs
  arm,arm64: do not always merge biovec if we are running on Xen
  swiotlb: print a warning when the swiotlb is full
  swiotlb-xen: use xen_dma_map/unmap_page, xen_dma_sync_single_for_cpu/device
  xen: introduce xen_dma_map/unmap_page and xen_dma_sync_single_for_cpu/device
  swiotlb-xen: use xen_alloc/free_coherent_pages
  xen: introduce xen_alloc/free_coherent_pages
  arm64/xen: get_dma_ops: return xen_dma_ops if we are running as xen_initial_domain
  arm/xen: get_dma_ops: return xen_dma_ops if we are running as xen_initial_domain
  swiotlb-xen: introduce xen_swiotlb_set_dma_mask
  xen/arm,arm64: enable SWIOTLB_XEN
  xen: make xen_create_contiguous_region return the dma address
  xen/x86: allow __set_phys_to_machine for autotranslate guests
  arm/xen,arm64/xen: introduce p2m
  arm64: define DMA_ERROR_CODE
  arm: make SWIOTLB available

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Conflicts:
	arch/arm/include/asm/dma-mapping.h
	drivers/xen/swiotlb-xen.c

[Conflicts arose b/c "arm: make SWIOTLB available" v8 was in Stefano's
branch, while I had v9 + Ack from Russel. I also fixed up white-space
issues]
2013-11-08 16:10:48 -05:00
Stefano Stabellini
fbd989b1d7 arm: make SWIOTLB available
IOMMU_HELPER is needed because SWIOTLB calls iommu_is_span_boundary,
provided by lib/iommu_helper.c.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: will.deacon@arm.com
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>

Changes in v9:
- remove uneeded include asm/cacheflush.h;
- just return 0 if !dev->dma_mask in dma_capable.

Changes in v8:
- use __phys_to_pfn and __pfn_to_phys.

Changes in v7:
- dma_mark_clean: empty implementation;
- in dma_capable use coherent_dma_mask if dma_mask hasn't been
  allocated.

Changes in v6:
- check for dev->dma_mask being NULL in dma_capable.

Changes in v5:
- implement dma_mark_clean using dmac_flush_range.

Changes in v3:
- dma_capable: do not treat dma_mask as a limit;
- remove SWIOTLB dependency on NEED_SG_DMA_LENGTH.
2013-11-08 15:16:07 -05:00
Santosh Shilimkar
26ba47b183 ARM: 7805/1: mm: change max*pfn to include the physical offset of memory
Most of the kernel code assumes that max*pfn is maximum pfns because
the physical start of memory is expected to be PFN0. Since this
assumption is not true on ARM architectures, the meaning of max*pfn
is number of memory pages. This is done to keep drivers happy which
are making use of of these variable to calculate the dma bounce limit
using dma_mask.

Now since we have a architecture override possibility for DMAable
maximum pfns, lets make meaning of max*pfns as maximum pnfs on ARM
as well.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-10-31 14:49:29 +00:00
Stefano Stabellini
c7e9bc5483 arm/xen: get_dma_ops: return xen_dma_ops if we are running as xen_initial_domain
We can't simply override arm_dma_ops with xen_dma_ops because devices
are allowed to have their own dma_ops and they take precedence over
arm_dma_ops. When running on Xen as initial domain, we always want
xen_dma_ops to be the one in use.

We introduce __generic_dma_ops to allow xen_dma_ops functions to call
back to the native implementation.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
CC: will.deacon@arm.com
CC: linux@arm.linux.org.uk

Changes in v7:
- return xen_dma_ops only if we are the initial domain;
- rename __get_dma_ops to __generic_dma_ops.
2013-10-18 16:01:26 +00:00
Stefano Stabellini
06e6295bce arm: make SWIOTLB available
IOMMU_HELPER is needed because SWIOTLB calls iommu_is_span_boundary,
provided by lib/iommu_helper.c.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: will.deacon@arm.com
CC: linux@arm.linux.org.uk


Changes in v8:
- use __phys_to_pfn and __pfn_to_phys.

Changes in v7:
- dma_mark_clean: empty implementation;
- in dma_capable use coherent_dma_mask if dma_mask hasn't been
  allocated.

Changes in v6:
- check for dev->dma_mask being NULL in dma_capable.

Changes in v5:
- implement dma_mark_clean using dmac_flush_range.

Changes in v3:
- dma_capable: do not treat dma_mask as a limit;
- remove SWIOTLB dependency on NEED_SG_DMA_LENGTH.
2013-10-15 15:47:14 +00:00
Linus Torvalds
787314c35f IOMMU Updates for Linux v3.8
A few new features this merge-window. The most important one is
 probably, that dma-debug now warns if a dma-handle is not checked with
 dma_mapping_error by the device driver. This requires minor changes to
 some architectures which make use of dma-debug. Most of these changes
 have the respective Acks by the Arch-Maintainers.
 Besides that there are updates to the AMD IOMMU driver for refactor the
 IOMMU-Groups support and to make sure it does not trigger a hardware
 erratum.
 The OMAP changes (for which I pulled in a branch from Tony Lindgren's
 tree) have a conflict in linux-next with the arm-soc tree. The conflict
 is in the file arch/arm/mach-omap2/clock44xx_data.c which is deleted in
 the arm-soc tree. It is safe to delete the file too so solve the
 conflict. Similar changes are done in the arm-soc tree in the common
 clock framework migration. A missing hunk from the patch in the IOMMU
 tree will be submitted as a seperate patch when the merge-window is
 closed.
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Merge tag 'iommu-updates-v3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull IOMMU updates from Joerg Roedel:
 "A few new features this merge-window.  The most important one is
  probably, that dma-debug now warns if a dma-handle is not checked with
  dma_mapping_error by the device driver.  This requires minor changes
  to some architectures which make use of dma-debug.  Most of these
  changes have the respective Acks by the Arch-Maintainers.

  Besides that there are updates to the AMD IOMMU driver for refactor
  the IOMMU-Groups support and to make sure it does not trigger a
  hardware erratum.

  The OMAP changes (for which I pulled in a branch from Tony Lindgren's
  tree) have a conflict in linux-next with the arm-soc tree.  The
  conflict is in the file arch/arm/mach-omap2/clock44xx_data.c which is
  deleted in the arm-soc tree.  It is safe to delete the file too so
  solve the conflict.  Similar changes are done in the arm-soc tree in
  the common clock framework migration.  A missing hunk from the patch
  in the IOMMU tree will be submitted as a seperate patch when the
  merge-window is closed."

* tag 'iommu-updates-v3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (29 commits)
  ARM: dma-mapping: support debug_dma_mapping_error
  ARM: OMAP4: hwmod data: ipu and dsp to use parent clocks instead of leaf clocks
  iommu/omap: Adapt to runtime pm
  iommu/omap: Migrate to hwmod framework
  iommu/omap: Keep mmu enabled when requested
  iommu/omap: Remove redundant clock handling on ISR
  iommu/amd: Remove obsolete comment
  iommu/amd: Don't use 512GB pages
  iommu/tegra: smmu: Move bus_set_iommu after probe for multi arch
  iommu/tegra: gart: Move bus_set_iommu after probe for multi arch
  iommu/tegra: smmu: Remove unnecessary PTC/TLB flush all
  tile: dma_debug: add debug_dma_mapping_error support
  sh: dma_debug: add debug_dma_mapping_error support
  powerpc: dma_debug: add debug_dma_mapping_error support
  mips: dma_debug: add debug_dma_mapping_error support
  microblaze: dma-mapping: support debug_dma_mapping_error
  ia64: dma_debug: add debug_dma_mapping_error support
  c6x: dma_debug: add debug_dma_mapping_error support
  ARM64: dma_debug: add debug_dma_mapping_error support
  intel-iommu: Prevent devices with RMRRs from being placed into SI Domain
  ...
2012-12-20 10:07:25 -08:00
Linus Torvalds
c2714334b9 ARM: arm-soc: Updates for Marvell mvebu/kirkwood
This is a branch with updates for Marvell's mvebu/kirkwood platforms. They
 came in late-ish, and were heavily interdependent such that it didn't
 make sense to split them up across the cross-platform topic branches. So
 here they are (for the second release in a row) in a branch on their own.
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Merge tag 'mvebu' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC updates for Marvell mvebu/kirkwood from Olof Johansson:
 "This is a branch with updates for Marvell's mvebu/kirkwood platforms.
  They came in late-ish, and were heavily interdependent such that it
  didn't make sense to split them up across the cross-platform topic
  branches.  So here they are (for the second release in a row) in a
  branch on their own."

* tag 'mvebu' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (88 commits)
  arm: l2x0: add aurora related properties to OF binding
  arm: mvebu: add Aurora L2 Cache Controller to the DT
  arm: mvebu: add L2 cache support
  dma: mv_xor: fix error handling path
  dma: mv_xor: fix error checking of irq_of_parse_and_map()
  dma: mv_xor: use request_irq() instead of devm_request_irq()
  dma: mv_xor: clear the window override control registers
  arm: mvebu: fix address decoding armada_cfg_base() function
  ARM: mvebu: update defconfig with I2C and RTC support
  ARM: mvebu: Add SATA support for OpenBlocks AX3-4
  ARM: mvebu: Add support for the RTC in OpenBlocks AX3-4
  ARM: mvebu: Add support for I2C on OpenBlocks AX3-4
  ARM: mvebu: Add support for I2C controllers in Armada 370/XP
  arm: mvebu: Add hardware I/O Coherency support
  arm: plat-orion: Add coherency attribute when setup mbus target
  arm: dma mapping: Export a dma ops function arm_dma_set_mask
  arm: mvebu: Add SMP support for Armada XP
  arm: mm: Add support for PJ4B cpu and init routines
  arm: mvebu: Add IPI support via doorbells
  arm: mvebu: Add initial support for power managmement service unit
  ...
2012-12-14 14:54:26 -08:00
Ming Lei
a015757304 ARM: dma-mapping: support debug_dma_mapping_error
Without the patch, kind of below warning will be dumped if DMA-API
debug is enabled:

[   11.069763] ------------[ cut here ]------------
[   11.074645] WARNING: at lib/dma-debug.c:948 check_unmap+0x770/0x860()
[   11.081420] ehci-omap ehci-omap.0: DMA-API: device driver failed to
check map error[device address=0x0000000
0adb78e80] [size=8 bytes] [mapped as single]
[   11.095611] Modules linked in:

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2012-12-03 18:55:28 +01:00
Gregory CLEMENT
87b54e786a arm: dma mapping: Export a dma ops function arm_dma_set_mask
Expose another DMA operations function: arm_dma_set_mask. This
function will be added to a custom DMA ops for Armada 370/XP.
Depending of its configuration Armada 370/XP can be set as a "nearly"
coherent architecture. In this case the DMA ops is made of:
- specific functions for this architecture
- already exposed arm DMA related functions
- the arm_dma_set_mask which was not exposed yet.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
2012-11-21 17:07:49 +01:00
Marek Szyprowski
16cf8a80a8 ARM: dma-mapping: remove init_consistent_dma_size() stub
Since commit e9da6e9905 ("ARM: dma-mapping: remove custom consistent
dma region") setting consistent dma memory size is not longer required. All
calls to this function has been already removed, so the
init_consistent_dma_size() stub can also be gone.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2012-11-13 10:13:23 +01:00
Marek Szyprowski
6975758966 Revert "ARM: dma-mapping: support debug_dma_mapping_error"
This reverts commit 871ae57adc, which is
scheduled for v3.8 and accidently got into v3.7-rc series.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2012-10-26 07:39:13 +02:00
Ming Lei
871ae57adc ARM: dma-mapping: support debug_dma_mapping_error
Without the patch, kind of below warning will be dumped if DMA-API
debug is enabled:

[   11.069763] ------------[ cut here ]------------
[   11.074645] WARNING: at lib/dma-debug.c:948 check_unmap+0x770/0x860()
[   11.081420] ehci-omap ehci-omap.0: DMA-API: device driver failed to
check map error[device address=0x0000000
0adb78e80] [size=8 bytes] [mapped as single]
[   11.095611] Modules linked in:

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2012-10-23 14:05:34 +02:00
Rob Herring
dd37e9405a ARM: add coherent dma ops
arch_is_coherent is problematic as it is a global symbol. This
doesn't work for multi-platform kernels or platforms which can support
per device coherent DMA.

This adds arm_coherent_dma_ops to be used for devices which connected
coherently (i.e. to the ACP port on Cortex-A9 or A15). The arm_dma_ops
are modified at boot when arch_is_coherent is true.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2012-10-02 08:58:06 +02:00
Marek Szyprowski
6e5267aa54 ARM: DMA-Mapping: add function for setting coherent pool size from platform code
Some platforms might require to increase atomic coherent pool to make
sure that their device will be able to allocate all their buffers from
atomic context. This function can be also used to decrease atomic
coherent pool size if coherent allocations are not used for the given
sub-platform.

Suggested-by: Josh Coombs <josh.coombs@gmail.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2012-08-28 21:01:02 +02:00
Marek Szyprowski
dc2832e1e7 ARM: dma-mapping: add support for dma_get_sgtable()
This patch adds support for dma_get_sgtable() function which is required
to let drivers to share the buffers allocated by DMA-mapping subsystem.

Generic implementation based on virt_to_page() is not suitable for ARM
dma-mapping subsystem.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
2012-07-30 12:25:47 +02:00
Marek Szyprowski
64ccc9c033 common: dma-mapping: add support for generic dma_mmap_* calls
Commit 9adc5374 ('common: dma-mapping: introduce mmap method') added a
generic method for implementing mmap user call to dma_map_ops structure.

This patch converts ARM and PowerPC architectures (the only providers of
dma_mmap_coherent/dma_mmap_writecombine calls) to use this generic
dma_map_ops based call and adds a generic cross architecture
definition for dma_mmap_attrs, dma_mmap_coherent, dma_mmap_writecombine
functions.

The generic mmap virt_to_page-based fallback implementation is provided for
architectures which don't provide their own implementation for mmap method.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
2012-07-30 12:25:46 +02:00
Marek Szyprowski
e9da6e9905 ARM: dma-mapping: remove custom consistent dma region
This patch changes dma-mapping subsystem to use generic vmalloc areas
for all consistent dma allocations. This increases the total size limit
of the consistent allocations and removes platform hacks and a lot of
duplicated code.

Atomic allocations are served from special pool preallocated on boot,
because vmalloc areas cannot be reliably created in atomic context.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
2012-07-30 12:25:45 +02:00
Marek Szyprowski
f99d603412 ARM: dma-mapping: use alloc, mmap, free from dma_ops
This patch converts dma_alloc/free/mmap_{coherent,writecombine}
functions to use generic alloc/free/mmap methods from dma_map_ops
structure. A new DMA_ATTR_WRITE_COMBINE DMA attribute have been
introduced to implement writecombine methods.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-By: Subash Patel <subash.ramaswamy@linaro.org>
2012-05-21 15:06:22 +02:00
Marek Szyprowski
15237e1f50 ARM: dma-mapping: move all dma bounce code to separate dma ops structure
This patch removes dma bounce hooks from the common dma mapping
implementation on ARM architecture and creates a separate set of
dma_map_ops for dma bounce devices.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Tested-By: Subash Patel <subash.ramaswamy@linaro.org>
2012-05-21 15:06:18 +02:00
Marek Szyprowski
2dc6a016bb ARM: dma-mapping: use asm-generic/dma-mapping-common.h
This patch modifies dma-mapping implementation on ARM architecture to
use common dma_map_ops structure and asm-generic/dma-mapping-common.h
helpers.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Tested-By: Subash Patel <subash.ramaswamy@linaro.org>
2012-05-21 15:06:14 +02:00
Marek Szyprowski
a227fb92a0 ARM: dma-mapping: remove offset parameter to prepare for generic dma_ops
This patch removes the need for the offset parameter in dma bounce
functions. This is required to let dma-mapping framework on ARM
architecture to use common, generic dma_map_ops based dma-mapping
helpers.

Background and more detailed explaination:

dma_*_range_* functions are available from the early days of the dma
mapping api. They are the correct way of doing a partial syncs on the
buffer (usually used by the network device drivers). This patch changes
only the internal implementation of the dma bounce functions to let
them tunnel through dma_map_ops structure. The driver api stays
unchanged, so driver are obliged to call dma_*_range_* functions to
keep code clean and easy to understand.

The only drawback from this patch is reduced detection of the dma api
abuse. Let us consider the following code:

dma_addr = dma_map_single(dev, ptr, 64, DMA_TO_DEVICE);
dma_sync_single_range_for_cpu(dev, dma_addr+16, 0, 32, DMA_TO_DEVICE);

Without the patch such code fails, because dma bounce code is unable
to find the bounce buffer for the given dma_address. After the patch
the above sync call will be equivalent to:

dma_sync_single_range_for_cpu(dev, dma_addr, 16, 32, DMA_TO_DEVICE);

which succeeds.

I don't consider this as a real problem, because DMA API abuse should be
caught by debug_dma_* function family. This patch lets us to simplify
the internal low-level implementation without chaning the driver visible
API.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Tested-By: Subash Patel <subash.ramaswamy@linaro.org>
2012-05-21 15:06:13 +02:00
Marek Szyprowski
553ac78877 ARM: dma-mapping: introduce DMA_ERROR_CODE constant
Replace all uses of ~0 with DMA_ERROR_CODE, what should make the code
easier to read.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Tested-By: Subash Patel <subash.ramaswamy@linaro.org>
2012-05-21 15:06:12 +02:00
Linus Torvalds
1fdb24e969 Merge branch 'devel-stable' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm
* 'devel-stable' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm: (178 commits)
  ARM: 7139/1: fix compilation with CONFIG_ARM_ATAG_DTB_COMPAT and large TEXT_OFFSET
  ARM: gic, local timers: use the request_percpu_irq() interface
  ARM: gic: consolidate PPI handling
  ARM: switch from NO_MACH_MEMORY_H to NEED_MACH_MEMORY_H
  ARM: mach-s5p64x0: remove mach/memory.h
  ARM: mach-s3c64xx: remove mach/memory.h
  ARM: plat-mxc: remove mach/memory.h
  ARM: mach-prima2: remove mach/memory.h
  ARM: mach-zynq: remove mach/memory.h
  ARM: mach-bcmring: remove mach/memory.h
  ARM: mach-davinci: remove mach/memory.h
  ARM: mach-pxa: remove mach/memory.h
  ARM: mach-ixp4xx: remove mach/memory.h
  ARM: mach-h720x: remove mach/memory.h
  ARM: mach-vt8500: remove mach/memory.h
  ARM: mach-s5pc100: remove mach/memory.h
  ARM: mach-tegra: remove mach/memory.h
  ARM: plat-tcc: remove mach/memory.h
  ARM: mach-mmp: remove mach/memory.h
  ARM: mach-cns3xxx: remove mach/memory.h
  ...

Fix up mostly pretty trivial conflicts in:
 - arch/arm/Kconfig
 - arch/arm/include/asm/localtimer.h
 - arch/arm/kernel/Makefile
 - arch/arm/mach-shmobile/board-ap4evb.c
 - arch/arm/mach-u300/core.c
 - arch/arm/mm/dma-mapping.c
 - arch/arm/mm/proc-v7.S
 - arch/arm/plat-omap/Kconfig
largely due to some CONFIG option renaming (ie CONFIG_PM_SLEEP ->
CONFIG_ARM_CPU_SUSPEND for the arm-specific suspend code etc) and
addition of NEED_MACH_MEMORY_H next to HAVE_IDE.
2011-10-28 12:02:27 -07:00
Catalin Marinas
01f461a3a4 ARM: 7058/1: LPAE: Cast the dma_addr_t argument to unsigned long in dma_to_virt
This is to avoid a compiler warning when invoking the __bus_to_virt()
macro. The dma_to_virt() function gets addresses within the 32-bit
range.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-08-23 15:30:33 +01:00
Jon Medhurst
99d1717dd7 ARM: Add init_consistent_dma_size()
This function can be called during boot to increase the size of the consistent
DMA region above it's default value of 2MB. It must be called before the memory
allocator is initialised, i.e. before any core_initcall.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-08-22 12:00:10 +00:00
Russell King
022ae537b2 ARM: dma: replace ISA_DMA_THRESHOLD with a variable
ISA_DMA_THRESHOLD has been unused by non-arch code, so lets now get
rid of it from ARM by replacing it with arm_dma_zone_mask.  Move
dma_supported() and dma_set_mask() out of line, and have
dma_supported() check this new variable instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-12 11:08:12 +01:00
Russell King
3973c33775 ARM: dmabounce: simplify dma_set_mask()
Simplify the dmabounce specific code in dma_set_mask().  We can just
omit setting the dma mask if dmabounce is enabled (we will have already
set dma mask via callbacks when the device is created in that case.)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-08 14:02:21 +01:00
Russell King
0703ed2a6b ARM: dmabounce: get rid of dma_needs_bounce global function
Pass the device type specific needs_bounce function in at dmabounce
register time, avoiding the need for a platform specific global
function to do this.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-04 08:39:55 +01:00
Russell King
8021a4a048 ARM: dma-mapping: define dma_(un)?map_single in terms of dma_(un)?map_page
Use dma_map_page()/dma_unmap_page() internals to handle dma_map_single()
and dma_unmap_single().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-03 23:27:49 +01:00
Russell King
24056f5250 ARM: DMA: add support for DMA debugging
Add ARM support for the DMA debug infrastructure, which allows the
DMA API usage to be debugged.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-06 22:31:11 +00:00
Russell King
9eedd96301 ARM: DMA: Replace page_to_dma()/dma_to_page() with pfn_to_dma()/dma_to_pfn()
Replace the page_to_dma() and dma_to_page() macros with their PFN
equivalents.  This allows us to map parts of memory which do not have
a struct page allocated to them to bus addresses.  This will be used
internally by dma_alloc_coherent()/dma_alloc_writecombine().

Build tested on Versatile, OMAP1, IOP13xx and KS8695.

Tested-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-03 11:27:43 +00:00
Russell King
0485e18bc4 Revert "[ARM] pxa: remove now unnecessary dma_needs_bounce()"
This reverts commit 4fa5518, which causes a compilation regression for
IXP4xx platforms.

Reported-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-08 12:28:39 +01:00
Linus Torvalds
636d17427b Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (226 commits)
  ARM: 6323/1: cam60: don't use __init for cam60_spi_{flash_platform_data,partitions}
  ARM: 6324/1: cam60: move cam60_spi_devices to .init.data
  ARM: 6322/1: imx/pca100: Fix name of spi platform data
  ARM: 6321/1: fix syntax error in main Kconfig file
  ARM: 6297/1: move U300 timer to dynamic clock lookup
  ARM: 6296/1: clock U300 intcon and timer properly
  ARM: 6295/1: fix U300 apb_pclk split
  ARM: 6306/1: fix inverted MMC card detect in U300
  ARM: 6299/1: errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID
  ARM: 6294/1: etm: do a dummy read from OSSRR during initialization
  ARM: 6292/1: coresight: add ETM management registers
  ARM: 6288/1: ftrace: document mcount formats
  ARM: 6287/1: ftrace: clean up mcount assembly indentation
  ARM: 6286/1: fix Thumb-2 decompressor broken by "Auto calculate ZRELADDR"
  ARM: 6281/1: video/imxfb.c: allow usage without BACKLIGHT_CLASS_DEVICE
  ARM: 6280/1: imx: Fix build failure when including <mach/gpio.h> without <linux/spinlock.h>
  ARM: S5PV210: Fix on missing s3c-sdhci card detection method for hsmmc3
  ARM: S5P: Fix on missing S5P_DEV_FIMC in plat-s5p/Kconfig
  ARM: S5PV210: Override FIMC driver name on Aquila board
  ARM: S5PC100: enable FIMC on SMDKC100
  ...

Fix up conflicts in arch/arm/mach-{s5pc100,s5pv210}/cpu.c due to
different subsystem 'setname' calls, and trivial port types in
include/linux/serial_core.h
2010-08-11 09:13:19 -07:00
FUJITA Tomonori
3b9c6c11f5 dma-mapping: remove dma_is_consistent API
Architectures implement dma_is_consistent() in different ways (some
misinterpret the definition of API in DMA-API.txt).  So it hasn't been so
useful for drivers.  We have only one user of the API in tree.  Unlikely
out-of-tree drivers use the API.

Even if we fix dma_is_consistent() in some architectures, it doesn't look
useful at all.  It was invented long ago for some old systems that can't
allocate coherent memory at all.  It's better to export only APIs that are
definitely necessary for drivers.

Let's remove this API.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:21 -07:00
FUJITA Tomonori
4565f0170d dma-mapping: unify dma_get_cache_alignment implementations
dma_get_cache_alignment returns the minimum DMA alignment.  Architectures
defines it as ARCH_DMA_MINALIGN (formally ARCH_KMALLOC_MINALIGN).  So we
can unify dma_get_cache_alignment implementations.

Note that some architectures implement dma_get_cache_alignment wrongly.
dma_get_cache_alignment() should return the minimum DMA alignment.  So
fully-coherent architectures should return 1.  This patch also fixes this
issue.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:21 -07:00
Eric Miao
4fa5518c65 [ARM] pxa: remove now unnecessary dma_needs_bounce()
With a correct dev->dma_mask before calling dmabounce_register_dev(),
dma_needs_bounce() is not necessary.

The sa1111, though, is a bit complicated. Until it's fully understood
and fixed, dma_needs_bounce() for sa1111 is kept if CONFIG_SA1111 is
enabled with no side effect (with the condition of machine_is_*)

Thanks for Mike Rapoport to fix one error in the original version of
the patch and get this tested.

Acked-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
2010-08-05 14:32:21 +08:00
FUJITA Tomonori
6fee48cd33 dma-mapping: arm: use generic pci_set_dma_mask and pci_set_consistent_dma_mask
This converts arm to the generic pci_set_dma_mask and
pci_set_consistent_dma_mask (removes HAVE_ARCH_PCI_SET_DMA_MASK for
dmabounce).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Looked-over-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:42 -08:00
Russell King
4ea0d7371e ARM: dma-mapping: push buffer ownership down into dma-mapping.c
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-By: Santosh Shilimkar <santosh.shilimkar@ti.com>
2010-02-15 15:22:11 +00:00
Russell King
18eabe2347 ARM: dma-mapping: introduce the idea of buffer ownership
The DMA API has the notion of buffer ownership; make it explicit in the
ARM implementation of this API.  This gives us a set of hooks to allow
us to deal with CPU cache issues arising from non-cache coherent DMA.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-By: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-By: Jamie Iles <jamie@jamieiles.com>
2010-02-15 15:21:43 +00:00
Russell King
29cb8d0d24 ARM: dma-mapping: split dma_unmap_page() from dma_unmap_single()
We will need to treat dma_unmap_page() differently from dma_unmap_single()

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-By: Jamie Iles <jamie@jamieiles.com>
2009-11-23 12:53:55 +00:00
Russell King
ef1baed887 ARM: dma-mapping: provide dma_to_page()
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-By: Jamie Iles <jamie@jamieiles.com>
2009-11-23 12:53:54 +00:00
Russell King
1c4a4f48a1 ARM: dma-mapping: simplify page_to_dma() and __pfn_to_bus()
The non-highmem() and the __pfn_to_bus() based page_to_dma() both
compile to the same code, so its pointless having these two different
approaches.  Use the __pfn_to_bus() based version.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-By: Jamie Iles <jamie@jamieiles.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2009-11-23 12:53:26 +00:00
Nicolas Pitre
58edb51572 [ARM] make page_to_dma() highmem aware
If a machine class has a custom __virt_to_bus() implementation then it
must provide a __arch_page_to_dma() implementation as well which is
_not_ based on page_address() to support highmem.

This patch fixes existing __arch_page_to_dma() and provide a default
implementation otherwise.  The default implementation for highmem is
based on __pfn_to_bus() which is defined only when no custom
__virt_to_bus() is provided by the machine class.

That leaves only ebsa110 and footbridge which cannot support highmem
until they provide their own __arch_page_to_dma() implementation.
But highmem support on those legacy platforms with limited memory is
certainly not a priority.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:21 -04:00
Nicolas Pitre
43377453af [ARM] introduce dma_cache_maint_page()
This is a helper to be used by the DMA mapping API to handle cache
maintenance for memory identified by a page structure instead of a
virtual address.  Those pages may or may not be highmem pages, and
when they're highmem pages, they may or may not be virtually mapped.
When they're not mapped then there is no L1 cache to worry about. But
even in that case the L2 cache must be processed since unmapped highmem
pages can still be L2 cached.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:21 -04:00
Russell King
1124d6d21f [ARM] dma: correct dma_supported() implementation
dma_supported() is supposed to indicate whether the system can support
the DMA mask it was passed, which depends on the maximal address which
can be returned for DMA allocations.  If the mask is smaller than that,
we are unable to guarantee that the driver can reliably obtain suitable
memory.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-12-13 09:12:07 +00:00
Russell King
9fa767928f [ARM] dma-mapping: fix compiler warning
arch/arm/mm/dma-mapping.c: In function `dma_sync_sg_for_cpu':
arch/arm/mm/dma-mapping.c:588: warning: statement with no effect

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-11-13 14:33:51 +00:00