arch_setup_dma_ops() is used in device probe code paths to create an
IOMMU mapping and attach it to the device. The function assumes that the
device is attached to a device-specific IOMMU instance (or at least a
device-specific TLB in a shared IOMMU instance) and thus creates a
separate mapping for every device.
On several systems (Renesas R-Car Gen2 being one of them), that
assumption is not true, and IOMMU mappings must be shared between
multiple devices. In those cases the IOMMU driver knows better than the
generic ARM dma-mapping layer and attaches mapping to devices manually
with arm_iommu_attach_device(), which sets the DMA ops for the device.
The arch_setup_dma_ops() function takes this into account and bails out
immediately if the device already has DMA ops assigned. However, the
corresponding arch_teardown_dma_ops() function, called from driver
unbind code paths (including probe deferral), will tear the mapping down
regardless of who created it. When the device is reprobed
arch_setup_dma_ops() will be called again but won't perform any
operation as the DMA ops will still be set.
We need to reset the DMA ops in arch_teardown_dma_ops() to fix this.
However, we can't do so unconditionally, as then a new mapping would be
created by arch_setup_dma_ops() when the device is reprobed, regardless
of whether the device needs to share a mapping or not. We must thus keep
track of whether arch_setup_dma_ops() created the mapping, and only in
that case tear it down in arch_teardown_dma_ops().
Keep track of that information in the dev_archdata structure. As the
structure is embedded in all instances of struct device let's not grow
it, but turn the existing dma_coherent bool field into a bitfield that
can be used for other purposes.
Fixes: 09515ef5dd ("of/acpi: Configure dma operations at probe time for platform/amba/pci bus devices")
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The following commit:
commit 815dd18788
Author: Bart Van Assche <bart.vanassche@sandisk.com>
Date: Fri Jan 20 13:04:04 2017 -0800
treewide: Consolidate get_dma_ops() implementations
rearranges get_dma_ops in a way that xen_dma_ops are not returned when
running on Xen anymore, dev->dma_ops is returned instead (see
arch/arm/include/asm/dma-mapping.h:get_arch_dma_ops and
include/linux/dma-mapping.h:get_dma_ops).
Fix the problem by storing dev->dma_ops in dev_archdata, and setting
dev->dma_ops to xen_dma_ops. This way, xen_dma_ops is returned naturally
by get_dma_ops. The Xen code can retrieve the original dev->dma_ops from
dev_archdata when needed. It also allows us to remove __generic_dma_ops
from common headers.
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Julien Grall <julien.grall@arm.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@vger.kernel.org> [4.11+]
CC: linux@armlinux.org.uk
CC: catalin.marinas@arm.com
CC: will.deacon@arm.com
CC: boris.ostrovsky@oracle.com
CC: jgross@suse.com
CC: Julien Grall <julien.grall@arm.com>
Some but not all architectures provide set_dma_ops(). Move dma_ops
from struct dev_archdata into struct device such that it becomes
possible on all architectures to configure dma_ops per device.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Russell King <linux@armlinux.org.uk>
Cc: x86@kernel.org
Signed-off-by: Doug Ledford <dledford@redhat.com>
Introduce a boolean flag and an accessor function to check whether a
device is dma_coherent. Set the flag from set_arch_dma_coherent_ops.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
This can be built without CONFIG_ARM_DMA_USE_IOMMU.
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
This patch add a complete implementation of DMA-mapping API for
devices which have IOMMU support.
This implementation tries to optimize dma address space usage by remapping
all possible physical memory chunks into a single dma address space chunk.
DMA address space is managed on top of the bitmap stored in the
dma_iommu_mapping structure stored in device->archdata. Platform setup
code has to initialize parameters of the dma address space (base address,
size, allocation precision order) with arm_iommu_create_mapping() function.
To reduce the size of the bitmap, all allocations are aligned to the
specified order of base 4 KiB pages.
dma_alloc_* functions allocate physical memory in chunks, each with
alloc_pages() function to avoid failing if the physical memory gets
fragmented. In worst case the allocated buffer is composed of 4 KiB page
chunks.
dma_map_sg() function minimizes the total number of dma address space
chunks by merging of physical memory chunks into one larger dma address
space chunk. If requested chunk (scatter list entry) boundaries
match physical page boundaries, most calls to dma_map_sg() requests will
result in creating only one chunk in dma address space.
dma_map_page() simply creates a mapping for the given page(s) in the dma
address space.
All dma functions also perform required cache operation like their
counterparts from the arm linear physical memory mapping version.
This patch contains code and fixes kindly provided by:
- Krishna Reddy <vdumpa@nvidia.com>,
- Andrzej Pietrasiewicz <andrzej.p@samsung.com>,
- Hiroshi DOYU <hdoyu@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-By: Subash Patel <subash.ramaswamy@linaro.org>
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>
Add a private iommu pointer to the ARM-specific arch data in the
device struct, which will be used to attach iommu-specific data
to devices which require iommu support.
Different iommu implementations (on different platforms) will attach
different types of data to this pointer, so 'void *' is currently used
(the downside is reduced typesafety).
Note: ia64, x86 and sparc have this exact iommu extension as well, and
if others are likely to adopt it too, we might want to consider
adding this to the device struct itself directly.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add omap_device pointer to the ARM-specific arch data in the
platform_device. This will be used to attach OMAP-specific
device-data to the platform device with device lifetime.
Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Allow architecture specific data in struct platform_device V3.
With this patch struct pdev_archdata is added to struct
platform_device, similar to struct dev_archdata in found in
struct device. Useful for architecture code that needs to
keep extra data associated with each platform device.
Struct pdev_archdata is different from dev.platform_data, the
convention is that dev.platform_data points to driver-specific
data. It may or may not be required by the driver. The format
of this depends on driver but is the same across architectures.
The structure pdev_archdata is a place for architecture specific
data. This data is handled by architecture specific code (for
example runtime PM), and since it is architecture specific it
should _never_ be touched by device driver code. Exactly like
struct dev_archdata but for platform devices.
[rjw: This change is for power management mostly and that's why it
goes through the suspend tree.]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Move platform independent header files to arch/arm/include/asm, leaving
those in asm/arch* and asm/plat* alone.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Laurent Pinchart