Commit Graph

73 Commits

Author SHA1 Message Date
David Brazdil
31c8025fac of: restricted dma: Fix condition for rmem init
of_dma_set_restricted_buffer fails to handle negative return values from
of_property_count_elems_of_size, e.g. when the property does not exist.
This results in an attempt to assign a non-existent reserved memory
region to the device and a warning being printed. Fix the condition to
take negative values into account.

Fixes: f3cfd136ae ("of: restricted dma: Don't fail device probe on rmem init failure")
Cc: Will Deacon <will@kernel.org>
Signed-off-by: David Brazdil <dbrazdil@google.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210917131423.2760155-1-dbrazdil@google.com
Signed-off-by: Rob Herring <robh@kernel.org>
2021-09-17 15:58:09 -05:00
Will Deacon
f3cfd136ae of: restricted dma: Don't fail device probe on rmem init failure
If CONFIG_DMA_RESTRICTED_POOL=n then probing a device with a reference
to a "restricted-dma-pool" will fail with a reasonably cryptic error:

  | pci-host-generic: probe of 10000.pci failed with error -22

Rework of_dma_set_restricted_buffer() so that it does not cause probing
failure and instead either returns early if CONFIG_DMA_RESTRICTED_POOL=n
or emits a diagnostic if the reserved DMA pool fails to initialise.

Cc: Claire Chang <tientzu@chromium.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-08-23 06:32:04 -04:00
Will Deacon
ce5cb67c66 of: Move of_dma_set_restricted_buffer() into device.c
Rob observes that:

  | of_dma_set_restricted_buffer() [...] should also be moved to
  | of/device.c. There's no reason for it to be in of/address.c. It has
  | nothing to do with address parsing.

Move it to of/device.c, as he suggests.

Cc: Claire Chang <tientzu@chromium.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Robin Murphy <robin.murphy@arm.com>
Suggested-by: Rob Herring <robh+dt@kernel.org>
Link: https://lore.kernel.org/r/CAL_JsqJ7ROWWJX84x2kEex9NQ8G+2=ybRuNOobX+j8bjZzSemQ@mail.gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-08-23 06:32:02 -04:00
Claire Chang
fec9b62509 of: Add plumbing for restricted DMA pool
If a device is not behind an IOMMU, we look up the device node and set
up the restricted DMA when the restricted-dma-pool is presented.

Signed-off-by: Claire Chang <tientzu@chromium.org>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-07-13 20:04:53 -04:00
Lee Jones
cb61e9dbee of: device: Fix function name in header and provide missing descriptions
Fixes the following W=1 kernel build warning(s):

 drivers/of/device.c:72: warning: expecting prototype for of_dma_configure(). Prototype was for of_dma_configure_id() instead
 drivers/of/device.c:263: warning: Function parameter or member 'dev' not described in 'of_device_modalias'
 drivers/of/device.c:263: warning: Function parameter or member 'str' not described in 'of_device_modalias'
 drivers/of/device.c:263: warning: Function parameter or member 'len' not described in 'of_device_modalias'
 drivers/of/device.c:280: warning: Function parameter or member 'dev' not described in 'of_device_uevent'
 drivers/of/device.c:280: warning: Function parameter or member 'env' not described in 'of_device_uevent'

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210318104036.3175910-2-lee.jones@linaro.org
2021-03-23 15:27:52 -06:00
Linus Torvalds
a99163e9e7 Merge tag 'devicetree-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull devicetree updates from Rob Herring:

 - Sync dtc to upstream version v1.6.0-51-g183df9e9c2b9 and build host
   fdtoverlay

 - Add kbuild support to build DT overlays (%.dtbo)

 - Drop NULLifying match table in of_match_device().

   In preparation for this, there are several driver cleanups to use
   (of_)?device_get_match_data().

 - Drop pointless wrappers from DT struct device API

 - Convert USB binding schemas to use graph schema and remove old plain
   text graph binding doc

 - Convert spi-nor and v3d GPU bindings to DT schema

 - Tree wide schema fixes for if/then schemas, array size constraints,
   and undocumented compatible strings in examples

 - Handle 'no-map' correctly for already reserved memblock regions

* tag 'devicetree-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (35 commits)
  driver core: platform: Drop of_device_node_put() wrapper
  of: Remove of_dev_{get,put}()
  dt-bindings: usb: Change descibe to describe in usbmisc-imx.txt
  dt-bindings: can: rcar_canfd: Group tuples in pin control properties
  dt-bindings: power: renesas,apmu: Group tuples in cpus properties
  dt-bindings: mtd: spi-nor: Convert to DT schema format
  dt-bindings: Use portable sort for version cmp
  dt-bindings: ethernet-controller: fix fixed-link specification
  dt-bindings: irqchip: Add node name to PRUSS INTC
  dt-bindings: interconnect: Fix the expected number of cells
  dt-bindings: Fix errors in 'if' schemas
  dt-bindings: iommu: renesas,ipmmu-vmsa: Make 'power-domains' conditionally required
  dt-bindings: Fix undocumented compatible strings in examples
  kbuild: Add support to build overlays (%.dtbo)
  scripts: dtc: Remove the unused fdtdump.c file
  scripts: dtc: Build fdtoverlay tool
  scripts/dtc: Update to upstream version v1.6.0-51-g183df9e9c2b9
  scripts: dtc: Fetch fdtoverlay.c from external DTC project
  dt-bindings: thermal: sun8i: Fix misplaced schema keyword in compatible strings
  dt-bindings: iio: dac: Fix AD5686 references
  ...
2021-02-22 10:05:12 -08:00
Rob Herring
83c4a4eec0 of: Remove of_dev_{get,put}()
of_dev_get() and of_dev_put are just wrappers for get_device()/put_device()
on a platform_device. There's also already platform_device_{get,put}()
wrappers for this purpose. Let's update the few users and remove
of_dev_{get,put}().

Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Julia Lawall <Julia.Lawall@inria.fr>
Cc: Gilles Muller <Gilles.Muller@inria.fr>
Cc: Nicolas Palix <nicolas.palix@imag.fr>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: netdev@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-usb@vger.kernel.org
Cc: cocci@systeme.lip6.fr
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210211232745.1498137-2-robh@kernel.org
2021-02-12 19:23:39 -06:00
Yong Wu
89c7cb1608 of/device: Update dma_range_map only when dev has valid dma-ranges
The commit e0d072782c ("dma-mapping: introduce DMA range map,
supplanting dma_pfn_offset") always update dma_range_map even though it was
already set, like in the sunxi_mbus driver. the issue is reported at [1].
This patch avoid this(Updating it only when dev has valid dma-ranges).

Meanwhile, dma_range_map contains the devices' dma_ranges information,
This patch moves dma_range_map before of_iommu_configure. The iommu
driver may need to know the dma_address requirements of its iommu
consumer devices.

[1] https://lore.kernel.org/linux-arm-kernel/5c7946f3-b56e-da00-a750-be097c7ceb32@arm.com/

CC: Frank Rowand <frowand.list@gmail.com>
Fixes: e0d072782c ("dma-mapping: introduce DMA range map, supplanting dma_pfn_offset"),
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210119105203.15530-1-yong.wu@mediatek.com
2021-01-27 14:00:14 -06:00
Geert Uytterhoeven
495023e4e4 of: Drop superfluous ULL suffix for ~0
There is no need to specify a "ULL" suffix for "all bits set": "~0" is
sufficient, and works regardless of type.  In fact adding the suffix
makes the code more fragile.

Fixes: 48ab6d5d1f ("dma-mapping: fix 32-bit overflow with CONFIG_ARM_LPAE=n")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-02 09:32:46 -08:00
Geert Uytterhoeven
48ab6d5d1f dma-mapping: fix 32-bit overflow with CONFIG_ARM_LPAE=n
On r8a7791/koelsch and shmobile_defconfig, PCIe probing fails with:

    rcar-pcie fe000000.pcie: Adjusted size 0x0 invalid
    rcar-pcie: probe of fe000000.pcie failed with error -22

of_dma_get_range() returns the following map:

    cpu_start 0x40000000 dma_start 0x40000000 size 0x080000000 offset 0
    cpu_start 0x00000000 dma_start 0x00000000 size 0x100000000 offset 0

If CONFIG_ARM_LPAE=n, dma_addr_t is 32-bit.  Hence when assigning
r->dma_start + r->size to dma_end, this value will be truncated to
32-bit, yielding zero when processing the second table entry.
Consequently, both dma_start and dma_end will be zero, leading to a zero
size.

Fix this by changing the dma_start and dma_end variables from dma_addr_t
to u64.

Fixes: e0d072782c ("dma-mapping: introduce DMA range map, supplanting dma_pfn_offset")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-29 16:59:34 +01:00
Christoph Hellwig
0a0f0d8be7 dma-mapping: split <linux/dma-mapping.h>
Split out all the bits that are purely for dma_map_ops implementations
and related code into a new <linux/dma-map-ops.h> header so that they
don't get pulled into all the drivers.  That also means the architecture
specific <asm/dma-mapping.h> is not pulled in by <linux/dma-mapping.h>
any more, which leads to a missing includes that were pulled in by the
x86 or arm versions in a few not overly portable drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:03 +02:00
Jim Quinlan
e0d072782c dma-mapping: introduce DMA range map, supplanting dma_pfn_offset
The new field 'dma_range_map' in struct device is used to facilitate the
use of single or multiple offsets between mapping regions of cpu addrs and
dma addrs.  It subsumes the role of "dev->dma_pfn_offset" which was only
capable of holding a single uniform offset and had no region bounds
checking.

The function of_dma_get_range() has been modified so that it takes a single
argument -- the device node -- and returns a map, NULL, or an error code.
The map is an array that holds the information regarding the DMA regions.
Each range entry contains the address offset, the cpu_start address, the
dma_start address, and the size of the region.

of_dma_configure() is the typical manner to set range offsets but there are
a number of ad hoc assignments to "dev->dma_pfn_offset" in the kernel
driver code.  These cases now invoke the function
dma_direct_set_offset(dev, cpu_addr, dma_addr, size).

Signed-off-by: Jim Quinlan <james.quinlan@broadcom.com>
[hch: various interface cleanups]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
2020-09-17 18:43:56 +02:00
Lorenzo Pieralisi
a081bd4af4 of/device: Add input id to of_dma_configure()
Devices sitting on proprietary busses have a device ID space that
is owned by the respective bus and related firmware bindings. In order
to let the generic OF layer handle the input translations to
an IOMMU id, for such busses the current of_dma_configure() interface
should be extended in order to allow the bus layer to provide the
device input id parameter - that is retrieved/assigned in bus
specific code and firmware.

Augment of_dma_configure() to add an optional input_id parameter,
leaving current functionality unchanged.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Link: https://lore.kernel.org/r/20200619082013.13661-8-lorenzo.pieralisi@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-28 15:51:32 +01:00
Masahiro Yamada
45586c7078 treewide: remove redundant IS_ERR() before error code check
'PTR_ERR(p) == -E*' is a stronger condition than IS_ERR(p).
Hence, IS_ERR(p) is unneeded.

The semantic patch that generates this commit is as follows:

// <smpl>
@@
expression ptr;
constant error_code;
@@
-IS_ERR(ptr) && (PTR_ERR(ptr) == - error_code)
+PTR_ERR(ptr) == - error_code
// </smpl>

Link: http://lkml.kernel.org/r/20200106045833.1725-1-masahiroy@kernel.org
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Acked-by: Stephen Boyd <sboyd@kernel.org> [drivers/clk/clk.c]
Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> [GPIO]
Acked-by: Wolfram Sang <wsa@the-dreams.de> [drivers/i2c]
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [acpi/scan.c]
Acked-by: Rob Herring <robh@kernel.org>
Cc: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:27 +00:00
Nicolas Saenz Julienne
a7ba70f178 dma-mapping: treat dev->bus_dma_mask as a DMA limit
Using a mask to represent bus DMA constraints has a set of limitations.
The biggest one being it can only hold a power of two (minus one). The
DMA mapping code is already aware of this and treats dev->bus_dma_mask
as a limit. This quirk is already used by some architectures although
still rare.

With the introduction of the Raspberry Pi 4 we've found a new contender
for the use of bus DMA limits, as its PCIe bus can only address the
lower 3GB of memory (of a total of 4GB). This is impossible to represent
with a mask. To make things worse the device-tree code rounds non power
of two bus DMA limits to the next power of two, which is unacceptable in
this case.

In the light of this, rename dev->bus_dma_mask to dev->bus_dma_limit all
over the tree and treat it as such. Note that dev->bus_dma_limit should
contain the higher accessible DMA address.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-11-21 18:14:35 +01:00
Jojo Zeng
8e94fd3622 of/device.c: fix the wrong comments
the comments which discribed the input parameters of of_match_device().
the name is changed, so fix it.

Signed-off-by: Jojo Zeng <jojo_zeng@126.com>
Reviewed-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2019-05-01 13:41:07 -05:00
Rob Herring
acc2038738 Merge branch 'yaml-bindings-for-v4.21' into dt/next 2018-12-13 11:20:36 -06:00
Rob Herring
e8b1dee214 of: Use device_type helpers to access the node type
Remove directly accessing device_node.type pointer and use the accessors
instead. This will eventually allow removing the type pointer.

Cc: Frank Rowand <frowand.list@gmail.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
2018-11-27 11:27:04 -06:00
Linus Torvalds
aa4330e15c Merge tag 'devicetree-fixes-for-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull Devicetree fixes from Rob Herring:

 - Add validation of NUMA distance map to prevent crashes with bad map

 - Fix setting of dma_mask

* tag 'devicetree-fixes-for-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  of, numa: Validate some distance map rules
  of/device: Really only set bus DMA mask when appropriate
2018-11-09 16:41:58 -06:00
Robin Murphy
6778be4e52 of/device: Really only set bus DMA mask when appropriate
of_dma_configure() was *supposed* to be following the same logic as
acpi_dma_configure() and only setting bus_dma_mask if some range was
specified by the firmware. However, it seems that subtlety got lost in
the process of fitting it into the differently-shaped control flow, and
as a result the force_dma==true case ends up always setting the bus mask
to the 32-bit default, which is not what anyone wants.

Make sure we only touch it if the DT actually said so.

Fixes: 6c2fb2ea76 ("of/device: Set bus DMA mask as appropriate")
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Reported-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Tested-by: John Stultz <john.stultz@linaro.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Robert Richter <robert.richter@cavium.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2018-11-08 12:44:34 -06:00
Linus Torvalds
b27186abb3 Merge tag 'devicetree-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull Devicetree updates from Rob Herring:
 "A bit bigger than normal as I've been busy this cycle.

  There's a few things with dependencies and a few things subsystem
  maintainers didn't pick up, so I'm taking them thru my tree.

  The fixes from Johan didn't get into linux-next, but they've been
  waiting for some time now and they are what's left of what subsystem
  maintainers didn't pick up.

  Summary:

   - Sync dtc with upstream version v1.4.7-14-gc86da84d30e4

   - Work to get rid of direct accesses to struct device_node name and
     type pointers in preparation for removing them. New helpers for
     parsing DT cpu nodes and conversions to use the helpers. printk
     conversions to %pOFn for printing DT node names. Most went thru
     subystem trees, so this is the remainder.

   - Fixes to DT child node lookups to actually be restricted to child
     nodes instead of treewide.

   - Refactoring of dtb targets out of arch code. This makes the support
     more uniform and enables building all dtbs on c6x, microblaze, and
     powerpc.

   - Various DT binding updates for Renesas r8a7744 SoC

   - Vendor prefixes for Facebook, OLPC

   - Restructuring of some ARM binding docs moving some peripheral
     bindings out of board/SoC binding files

   - New "secure-chosen" binding for secure world settings on ARM

   - Dual licensing of 2 DT IRQ binding headers"

* tag 'devicetree-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (78 commits)
  ARM: dt: relicense two DT binding IRQ headers
  power: supply: twl4030-charger: fix OF sibling-node lookup
  NFC: nfcmrvl_uart: fix OF child-node lookup
  net: stmmac: dwmac-sun8i: fix OF child-node lookup
  net: bcmgenet: fix OF child-node lookup
  drm/msm: fix OF child-node lookup
  drm/mediatek: fix OF sibling-node lookup
  of: Add missing exports of node name compare functions
  dt-bindings: Add OLPC vendor prefix
  dt-bindings: misc: bk4: Add device tree binding for Liebherr's BK4 SPI bus
  dt-bindings: thermal: samsung: Add SPDX license identifier
  dt-bindings: clock: samsung: Add SPDX license identifiers
  dt-bindings: timer: ostm: Add R7S9210 support
  dt-bindings: phy: rcar-gen2: Add r8a7744 support
  dt-bindings: can: rcar_can: Add r8a7744 support
  dt-bindings: timer: renesas, cmt: Document r8a7744 CMT support
  dt-bindings: watchdog: renesas-wdt: Document r8a7744 support
  dt-bindings: thermal: rcar: Add device tree support for r8a7744
  Documentation: dt: Add binding for /secure-chosen/stdout-path
  dt-bindings: arm: zte: Move sysctrl bindings to their own doc
  ...
2018-10-26 12:09:58 -07:00
Christoph Hellwig
dc3c05504d dma-mapping: remove dma_deconfigure
This goes through a lot of hooks just to call arch_teardown_dma_ops.
Replace it with a direct call instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-09-08 11:19:28 +02:00
Rob Herring
a613b26a50 of: Convert to using %pOFn instead of device_node.name
In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.

Reviewed-by: Frank Rowand <frank.rowand@sony.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: netdev@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
2018-09-07 11:04:41 -05:00
Robin Murphy
4d8bde883b OF: Don't set default coherent DMA mask
Now that we can track upstream DMA constraints properly with
bus_dma_mask instead of trying (and failing) to maintain it in
coherent_dma_mask, it doesn't make much sense for the firmware code to
be touching the latter at all. It's merely papering over bugs wherein a
driver has failed to call dma_set_coherent_mask() *and* the bus code has
not initialised any default value.

We don't really want to encourage more drivers coercing dma_mask so
we'll continue to fix that up if necessary, but add a warning to help
flush out any such buggy bus code that remains.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-07-27 19:01:07 +02:00
Robin Murphy
6c2fb2ea76 of/device: Set bus DMA mask as appropriate
When an explicit DMA limit is described by firmware, we need to remember
it regardless of how drivers might subsequently update their devices'
masks. The new bus_dma_mask field does that.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-07-27 19:01:05 +02:00