https://github.com/torvalds/linux
Revision 0ec9ebc706fbd394bc233d87ac7aaad1c4f3ab54 authored by Thomas Petazzoni on 08 July 2015, 14:28:14 UTC, committed by Vinod Koul on 31 July 2015, 15:03:43 UTC
Commit 6f166312c6ea2 ("dmaengine: mv_xor: add support for a38x command
in descriptor mode") introduced the support for a feature that
appeared in Armada 38x: specifying the operation to be performed in a
per-descriptor basis rather than globally per channel.

However, when doing so, it changed the function mv_chan_set_mode() to
use:

  if (IS_ENABLED(__BIG_ENDIAN))

instead of:

  #if defined(__BIG_ENDIAN)

While IS_ENABLED() is perfectly fine for CONFIG_* symbols, it is not
for other symbols such as __BIG_ENDIAN that is provided directly by
the compiler. Consequently, the commit broke support for big-endian,
as the XOR_DESCRIPTOR_SWAP flag was not set in the XOR channel
configuration register.

The primarily visible effect was some nasty warnings and failures
appearing during the self-test of the XOR unit:

[    1.197368] mv_xor d0060900.xor: error on chan 0. intr cause 0x00000082
[    1.197393] mv_xor d0060900.xor: config       0x00008440
[    1.197410] mv_xor d0060900.xor: activation   0x00000000
[    1.197427] mv_xor d0060900.xor: intr cause   0x00000082
[    1.197443] mv_xor d0060900.xor: intr mask    0x000003f7
[    1.197460] mv_xor d0060900.xor: error cause  0x00000000
[    1.197477] mv_xor d0060900.xor: error addr   0x00000000
[    1.197491] ------------[ cut here ]------------
[    1.197513] WARNING: CPU: 0 PID: 1 at ../drivers/dma/mv_xor.c:664 mv_xor_interrupt_handler+0x14c/0x170()

See also:

  http://storage.kernelci.org/next/next-20150617/arm-mvebu_v7_defconfig+CONFIG_CPU_BIG_ENDIAN=y/lab-khilman/boot-armada-xp-openblocks-ax3-4.txt

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Fixes: 6f166312c6ea2 ("dmaengine: mv_xor: add support for a38x command in descriptor mode")
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
1 parent cda8e93
Raw File
Tip revision: 0ec9ebc706fbd394bc233d87ac7aaad1c4f3ab54 authored by Thomas Petazzoni on 08 July 2015, 14:28:14 UTC
dmaengine: mv_xor: fix big endian operation in register mode
Tip revision: 0ec9ebc
Kconfig
#
# Block layer core configuration
#
menuconfig BLOCK
       bool "Enable the block layer" if EXPERT
       default y
       help
	 Provide block layer support for the kernel.

	 Disable this option to remove the block layer support from the
	 kernel. This may be useful for embedded devices.

	 If this option is disabled:

	   - block device files will become unusable
	   - some filesystems (such as ext3) will become unavailable.

	 Also, SCSI character devices and USB storage will be disabled since
	 they make use of various block layer definitions and facilities.

	 Say Y here unless you know you really don't want to mount disks and
	 suchlike.

if BLOCK

config LBDAF
	bool "Support for large (2TB+) block devices and files"
	depends on !64BIT
	default y
	help
	  Enable block devices or files of size 2TB and larger.

	  This option is required to support the full capacity of large
	  (2TB+) block devices, including RAID, disk, Network Block Device,
	  Logical Volume Manager (LVM) and loopback.
	
	  This option also enables support for single files larger than
	  2TB.

	  The ext4 filesystem requires that this feature be enabled in
	  order to support filesystems that have the huge_file feature
	  enabled.  Otherwise, it will refuse to mount in the read-write
	  mode any filesystems that use the huge_file feature, which is
	  enabled by default by mke2fs.ext4.

	  The GFS2 filesystem also requires this feature.

	  If unsure, say Y.

config BLK_DEV_BSG
	bool "Block layer SG support v4"
	default y
	help
	  Saying Y here will enable generic SG (SCSI generic) v4 support
	  for any block device.

	  Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4
	  can handle complicated SCSI commands: tagged variable length cdbs
	  with bidirectional data transfers and generic request/response
	  protocols (e.g. Task Management Functions and SMP in Serial
	  Attached SCSI).

	  This option is required by recent UDEV versions to properly
	  access device serial numbers, etc.

	  If unsure, say Y.

config BLK_DEV_BSGLIB
	bool "Block layer SG support v4 helper lib"
	default n
	select BLK_DEV_BSG
	help
	  Subsystems will normally enable this if needed. Users will not
	  normally need to manually enable this.

	  If unsure, say N.

config BLK_DEV_INTEGRITY
	bool "Block layer data integrity support"
	select CRC_T10DIF if BLK_DEV_INTEGRITY
	---help---
	Some storage devices allow extra information to be
	stored/retrieved to help protect the data.  The block layer
	data integrity option provides hooks which can be used by
	filesystems to ensure better data integrity.

	Say yes here if you have a storage device that provides the
	T10/SCSI Data Integrity Field or the T13/ATA External Path
	Protection.  If in doubt, say N.

config BLK_DEV_THROTTLING
	bool "Block layer bio throttling support"
	depends on BLK_CGROUP=y
	default n
	---help---
	Block layer bio throttling support. It can be used to limit
	the IO rate to a device. IO rate policies are per cgroup and
	one needs to mount and use blkio cgroup controller for creating
	cgroups and specifying per device IO rate policies.

	See Documentation/cgroups/blkio-controller.txt for more information.

config BLK_CMDLINE_PARSER
	bool "Block device command line partition parser"
	default n
	---help---
	Enabling this option allows you to specify the partition layout from
	the kernel boot args.  This is typically of use for embedded devices
	which don't otherwise have any standardized method for listing the
	partitions on a block device.

	See Documentation/block/cmdline-partition.txt for more information.

menu "Partition Types"

source "block/partitions/Kconfig"

endmenu

endif # BLOCK

config BLOCK_COMPAT
	bool
	depends on BLOCK && COMPAT
	default y

source block/Kconfig.iosched
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