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Thomas Petazzoni a0b5cd4ac2 bus: mvebu-mbus: use automatic I/O synchronization barriers
Instead of using explicit I/O synchronization barriers shoehorned
inside the streaming DMA mappings API (in
arch/arm/mach-mvebu/coherency.c), we are switching to use automatic
I/O synchronization barrier.

The primary motivation for this change is that explicit I/O
synchronization barriers are not only needed for streaming DMA
mappings (which can easily be done by overriding the dma_map_ops), but
also for coherent DMA mappings (which is a lot less easy to do, since
the kernel assumes such mappings are coherent and don't require any
sort of cache maintenance operation to ensure the consistency of the
buffers).

Switching to automatic I/O synchronization barriers will also allow us
to use the existing arm_coherent_dma_ops instead of our custom
arm_dma_ops.

In order to use automatic I/O synchronization barriers, this commit
changes mvebu-mbus in two ways:

 - It enables automatic I/O synchronization barriers in the 0x84
   register of the MBus bridge, by enabling such barriers for all MBus
   units. This enables automatic barriers for the on-SoC peripherals
   that are doing DMA.

 - It enables the SyncEnable bit in the MBus windows, so that PCIe
   devices also use automatic I/O synchronization barrier.

This automatic synchronization barrier relies on the assumption that
at least one register of a given hardware unit is read before the
driver accesses the DMA mappings modified by this unit. This
assumption is guaranteed for PCI devices by vertue of the PCI
standard, and we can reasonably verify that this assumption is also
true for the limited number of platform drivers doing DMA used on
Marvell EBU platforms.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
2015-01-19 16:05:42 -06:00
..
accessibility
acpi Merge branches 'acpi-pm', 'acpi-processor' and 'acpi-video' 2015-01-06 23:35:43 +01:00
amba Char/Misc driver patches for 3.19-rc1 2014-12-14 16:43:47 -08:00
android
ata More ACPI and power management updates for 3.19-rc1 2014-12-18 20:28:33 -08:00
atm Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
auxdisplay
base Merge branches 'pm-domains', 'powercap' and 'pm-tools' 2014-12-29 21:24:00 +01:00
bcma Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2014-12-11 17:56:37 -08:00
block Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2014-12-17 16:03:12 -08:00
bluetooth Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next 2014-12-15 13:23:09 -05:00
bus bus: mvebu-mbus: use automatic I/O synchronization barriers 2015-01-19 16:05:42 -06:00
cdrom
char ipmi: Fix compile warning with tv_usec 2014-12-30 13:34:36 -06:00
clk Please consider pulling the clk framework changes toward 3.19. It is 2014-12-20 16:42:36 -08:00
clocksource Fixes for 3.19 2014-12-30 15:27:20 +01:00
connector
coresight
cpufreq Merge branches 'pm-cpufreq' and 'pm-cpuidle' 2014-12-29 21:23:41 +01:00
cpuidle Merge branches 'pm-cpufreq' and 'pm-cpuidle' 2014-12-29 21:23:41 +01:00
crypto Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
dca
devfreq
dio
dma Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
dma-buf
edac Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
eisa
extcon Char/Misc driver patches for 3.19-rc1 2014-12-14 16:43:47 -08:00
firewire firewire: sbp2: replace card lock by target lock 2014-12-10 20:53:21 +01:00
firmware Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
fmc
gpio Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
gpu Merge tag 'amdkfd-fixes-2015-01-06' of git://people.freedesktop.org/~gabbayo/linux into drm-fixes 2015-01-08 10:36:37 +10:00
hid HID: roccat: potential out of bounds in pyra_sysfs_write_settings() 2015-01-09 14:41:01 +01:00
hsi * misc. fixes in omap-ssi and nokia-modem drivers 2014-12-15 17:33:47 -08:00
hv Char/Misc driver patches for 3.19-rc1 2014-12-14 16:43:47 -08:00
hwmon Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2014-12-17 10:16:27 -08:00
hwspinlock
i2c Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2014-12-20 13:52:52 -08:00
ide Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
idle
iio Staging patches for 3.19-rc1 2014-12-15 18:06:13 -08:00
infiniband SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
input Revert "Input: atmel_mxt_ts - use deep sleep mode when stopped" 2014-12-31 12:59:34 -08:00
iommu iommu/rockchip: Drop owner assignment from platform_drivers 2015-01-05 12:40:06 +01:00
ipack
irqchip Merge branch 'irq-irqdomain-arm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-12-15 17:30:09 -08:00
isdn Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2014-12-12 10:08:06 -08:00
leds More ACPI and power management updates for 3.19-rc1 2014-12-18 20:28:33 -08:00
lguest virtio: allow finalize_features to fail 2014-12-09 16:32:32 +02:00
macintosh macintosh: therm_pm72: delete deprecated driver 2014-12-19 19:32:47 +01:00
mailbox Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
mcb
md dm: fix missed error code if .end_io isn't implemented by target_type 2014-12-17 12:31:13 -05:00
media More ACPI and power management updates for 3.19-rc1 2014-12-18 20:28:33 -08:00
memory MTD updates for 3.19: 2014-12-17 09:59:26 -08:00
memstick
message
mfd Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2014-12-30 16:59:59 -08:00
misc powerpc updates for 3.19 batch 2 2014-12-19 12:57:45 -08:00
mmc mmc: core: stop trying to switch width when only one bit is supported 2014-12-29 14:49:28 +01:00
mtd MTD updates for 3.19: 2014-12-17 09:59:26 -08:00
net qla3xxx: don't allow never end busy loop 2015-01-06 17:41:36 -05:00
nfc More ACPI and power management updates for 3.19-rc1 2014-12-18 20:28:33 -08:00
ntb
nubus
of ARM: SoC/iommu configuration for 3.19 2014-12-16 14:53:01 -08:00
oprofile
parisc
parport Char/Misc driver patches for 3.19-rc1 2014-12-14 16:43:47 -08:00
pci Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-12-19 14:02:02 -08:00
pcmcia Char/Misc driver patches for 3.19-rc1 2014-12-14 16:43:47 -08:00
phy More ACPI and power management updates for 3.19-rc1 2014-12-18 20:28:33 -08:00
pinctrl pinctrl: st: Add irq_disable hook to st_gpio_irqchip 2015-01-07 10:44:39 +01:00
platform platform-drivers-x86 for 3.19 2014-12-18 20:24:55 -08:00
pnp
power More ACPI and power management updates for 3.19-rc1 2014-12-18 20:28:33 -08:00
powercap powercap / RAPL: add IDs for future Xeon CPUs 2014-12-17 02:35:42 +01:00
pps
ps3
ptp
pwm pwm: Changes for v3.19-rc1 2014-12-17 10:10:51 -08:00
rapidio
ras
regulator regulator: Fix for v3.19 2014-12-29 13:24:38 -08:00
remoteproc Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
reset Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
rpmsg
rtc Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
s390 Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
sbus
scsi qla2xxx: fix busy wait regression 2015-01-05 18:15:08 +01:00
sfi
sh drivers: sh / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM 2014-12-05 03:08:24 +01:00
sn
soc Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2014-12-15 15:52:01 -08:00
spi Merge remote-tracking branches 'spi/fix/img-spfi' and 'spi/fix/msiof' into spi-linus 2014-12-24 12:57:54 +00:00
spmi
ssb Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2014-12-11 17:56:37 -08:00
staging [regression] braino in "lustre: use is_root_inode()" 2014-12-26 22:43:19 -05:00
target SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
tc
thermal Merge branches 'thermal-core', 'thermal-soc' and 'thermal-int340x' of .git into next 2014-12-24 10:38:30 +08:00
thunderbolt
tty tty: 8250_omap: Replace CONFIG_PM_RUNTIME with CONFIG_PM 2014-12-19 15:27:58 +01:00
uio Char/Misc driver patches for 3.19-rc1 2014-12-14 16:43:47 -08:00
usb SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
uwb
vfio vfio-pci: Fix the check on pci device type in vfio_pci_probe() 2015-01-07 10:29:11 -07:00
vhost vhost/net: length miscalculation 2015-01-07 12:22:00 +02:00
video OMAPDSS: SDI: fix output port_num 2014-12-30 11:18:30 +02:00
virt
virtio virtio_pci: document why we defer kfree 2015-01-06 16:35:36 +02:00
vlynq
vme
w1 Char/Misc driver patches for 3.19-rc1 2014-12-14 16:43:47 -08:00
watchdog watchdog: imx2_wdt: Fix the argument of watchdog_active() 2014-12-18 16:01:20 +01:00
xen Merge remote-tracking branch 'scsi-queue/drivers-for-3.19' into for-linus 2014-12-18 05:56:29 -08:00
zorro
Kconfig Staging patches for 3.19-rc1 2014-12-15 18:06:13 -08:00
Makefile drivers: Move iommu/ before gpu/ in Makefile 2014-12-22 11:47:37 +02:00