GitHub/LineageOS/android_kernel_motorola_exynos9610.git
10 years agopowerpc: Update contact info in Documentation files
sukadev@linux.vnet.ibm.com [Wed, 1 Oct 2014 06:03:21 +0000 (23:03 -0700)]
powerpc: Update contact info in Documentation files

Cody's email address has changed. Update the contact information for
the 24x7 and GPCI counters to the PowerPC developers mailing list.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/perf/hv-24x7: Simplify catalog_read()
sukadev@linux.vnet.ibm.com [Wed, 1 Oct 2014 06:03:18 +0000 (23:03 -0700)]
powerpc/perf/hv-24x7: Simplify catalog_read()

catalog_read() implements the read interface for the sysfs file

/sys/bus/event_source/devices/hv_24x7/interface/catalog

It essentially takes a buffer, an offset and count as parameters
to the read() call.  It makes a hypervisor call to read a specific
page from the catalog and copy the required bytes into the given
buffer. Each call to catalog_read() returns at most one 4K page.

Given these requirements, we should be able to simplify the
catalog_read().

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/perf/hv-24x7: use kmem_cache instead of aligned stack allocations
Cody P Schafer [Wed, 1 Oct 2014 06:03:17 +0000 (23:03 -0700)]
powerpc/perf/hv-24x7: use kmem_cache instead of aligned stack allocations

Ian pointed out the use of __aligned(4096) caused rather large stack
consumption in single_24x7_request(), so use the kmem_cache
hv_page_cache (which we've already got set up for other allocations)
insead of allocating locally.

CC: Haren Myneni <hbabu@us.ibm.com>
Reported-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Cody P Schafer <dev@codyps.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Fix endian bug in LPC bus debugfs accessors
Benjamin Herrenschmidt [Fri, 3 Oct 2014 07:12:25 +0000 (17:12 +1000)]
powerpc/powernv: Fix endian bug in LPC bus debugfs accessors

When reading from the LPC, the OPAL FW calls return the value via pointer
to a uint32_t which is always returned big endian. Our internal inb/outb
implementation byteswaps that fine but our debugfs code is still broken.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agoMerge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux.git
Michael Ellerman [Fri, 3 Oct 2014 22:59:06 +0000 (08:59 +1000)]
Merge branch 'next' of git://git./linux/kernel/git/scottwood/linux.git

Freescale updates from Scott (27 commits):

  "Highlights include DMA32 zone support (SATA, USB, etc now works on 64-bit
   FSL kernels), MSI changes, 8xx optimizations and cleanup, t104x board
   support, and PrPMC PCI enumeration."

10 years agopowerpc: Enable CONFIG_CRASH_DUMP=y for ppc64_defconfig
Michael Ellerman [Wed, 24 Sep 2014 05:57:11 +0000 (15:57 +1000)]
powerpc: Enable CONFIG_CRASH_DUMP=y for ppc64_defconfig

It pulls in more code, including causing us to build a relocatable
kernel, which is good for testing.

The resulting kernel is still usable as a non-crash dump kernel.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/kdump: crash_dump.c needs to include io.h
Michael Ellerman [Wed, 24 Sep 2014 05:57:12 +0000 (15:57 +1000)]
powerpc/kdump: crash_dump.c needs to include io.h

For __ioremap().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Don't build powernv for other platform defconfigs
Michael Ellerman [Wed, 24 Sep 2014 05:57:10 +0000 (15:57 +1000)]
powerpc: Don't build powernv for other platform defconfigs

Because powernv arrived after these other platforms, the defconfigs
didn't have PPC_POWERNV disabled, and being default y it gets turned on.

If we're going to bother having defconfigs for the specific platforms
then they should only build the code required for those platforms.

The grab bag of everything config is ppc64_defconfig.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/pci: remove duplicate declaration of pci_bus_find_capability
Wei Yang [Fri, 19 Sep 2014 09:25:22 +0000 (17:25 +0800)]
powerpc/pci: remove duplicate declaration of pci_bus_find_capability

pci_bus_find_capability() is decleared in pci.h, so it is not necessary to do
it again.

This patch removes it.

Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/iommu/ddw: Fix endianness
Alexey Kardashevskiy [Thu, 25 Sep 2014 06:39:18 +0000 (16:39 +1000)]
powerpc/iommu/ddw: Fix endianness

rtas_call() accepts and returns values in CPU endianness.
The ddw_query_response and ddw_create_response structs members are
defined and treated as BE but as they are passed to rtas_call() as
(u32 *) and they get byteswapped automatically, the data is CPU-endian.
This fixes ddw_query_response and ddw_create_response definitions and use.

of_read_number() is designed to work with device tree cells - it assumes
the input is big-endian and returns data in CPU-endian. However due
to the ddw_create_response struct fix, create.addr_hi/lo are already
CPU-endian so do not byteswap them.

ddw_avail is a pointer to the "ibm,ddw-applicable" property which contains
3 cells which are big-endian as it is a device tree. rtas_call() accepts
a RTAS token in CPU-endian. This makes use of of_property_read_u32_array
to byte swap and avoid the need for a number of be32_to_cpu calls.

Cc: stable@vger.kernel.org # v3.13+
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[aik: folded Anton's patch with of_property_read_u32_array]
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Add printk levels to powerpc code
Anton Blanchard [Wed, 17 Sep 2014 04:39:39 +0000 (14:39 +1000)]
powerpc: Add printk levels to powerpc code

Add printk levels to some places in the powerpc port.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Add printk levels to powernv platform code
Anton Blanchard [Wed, 17 Sep 2014 04:39:38 +0000 (14:39 +1000)]
powerpc: Add printk levels to powernv platform code

Add printk levels to powernv platform code, and convert to
pr_err() etc while here.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Remove powerpc specific cmd_line
Anton Blanchard [Wed, 17 Sep 2014 04:39:36 +0000 (14:39 +1000)]
powerpc: Remove powerpc specific cmd_line

There is no need for yet another copy of the command line, just
use boot_command_line like everyone else.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Use pr_fmt in module loader code
Anton Blanchard [Wed, 17 Sep 2014 04:39:35 +0000 (14:39 +1000)]
powerpc: Use pr_fmt in module loader code

Use pr_fmt to give some context to the error messages in the
module code, and convert open coded debug printk to pr_debug.

Use pr_err for error messages.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Fill in si_addr_lsb siginfo field
Anton Blanchard [Wed, 24 Sep 2014 06:59:58 +0000 (16:59 +1000)]
powerpc: Fill in si_addr_lsb siginfo field

Fill in the si_addr_lsb siginfo field so the hwpoison code can
pass to userspace the length of memory that has been corrupted.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Add VM_FAULT_HWPOISON handling to powerpc page fault handler
Anton Blanchard [Wed, 24 Sep 2014 06:59:57 +0000 (16:59 +1000)]
powerpc: Add VM_FAULT_HWPOISON handling to powerpc page fault handler

do_page_fault was missing knowledge of HWPOISON, and we would oops
if userspace tried to access a poisoned page:

kernel BUG at arch/powerpc/mm/fault.c:180!

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Simplify do_sigbus
Anton Blanchard [Wed, 24 Sep 2014 06:59:56 +0000 (16:59 +1000)]
powerpc: Simplify do_sigbus

Exit out early for a kernel fault, avoiding indenting of
most of the function.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Speed up clear_page by unrolling it
Anton Blanchard [Thu, 2 Oct 2014 05:44:21 +0000 (15:44 +1000)]
powerpc: Speed up clear_page by unrolling it

Unroll clear_page 8 times. A simple microbenchmark which
allocates and frees a zeroed page:

for (i = 0; i < iterations; i++) {
unsigned long p = __get_free_page(GFP_KERNEL | __GFP_ZERO);
free_page(p);
}

improves 20% on POWER8.

This assumes cacheline sizes won't grow beyond 512 bytes or
page sizes wont drop below 1kB, which is unlikely, but we could
add a runtime check during early init if it makes people nervous.

Michael found that some versions of gcc produce quite bad code
(all multiplies), so we give gcc a hand by using shifts and adds.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Show hex prefix for PE state sysfs
Gavin Shan [Wed, 1 Oct 2014 04:34:51 +0000 (14:34 +1000)]
powerpc/eeh: Show hex prefix for PE state sysfs

As Michael suggested, the hex prefix for the output of EEH PE
state sysfs entry (/sys/bus/pci/devices/xxx/eeh_pe_state) is
always informative to users.

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Override dma_get_required_mask()
Gavin Shan [Tue, 30 Sep 2014 02:39:10 +0000 (12:39 +1000)]
powerpc/powernv: Override dma_get_required_mask()

The dma_get_required_mask() function is used by some drivers to
query the platform about what DMA mask is needed to cover all of
memory. This is a bit of a strange semantic when we have to choose
between IOMMU translation or bypass, but essentially what it means
is "what DMA mask will give best performances".

Currently, our IOMMU backend always returns a 32-bit mask here, we
don't do anything special to it when we have bypass available. This
causes some drivers to choose a 32-bit mask, thus losing the ability
to use the bypass window, thinking this is more efficient. The problem
was reported from the driver of following device:

0004:03:00.0 0107: 1000:0087 (rev 05)
0004:03:00.0 Serial Attached SCSI controller: LSI Logic / Symbios \
             Logic SAS2308 PCI-Express Fusion-MPT SAS-2 (rev 05)

This patch adds an override of that function in order to, instead,
return a 64-bit mask whenever a bypass window is available in order
for drivers to prefer this configuration.

Reported-by: Murali N. Iyer <mniyer@us.ibm.com>
Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Fetch frozen PE on top level
Gavin Shan [Tue, 30 Sep 2014 02:39:09 +0000 (12:39 +1000)]
powerpc/powernv: Fetch frozen PE on top level

It should have been part of commit 1ad7a72c5 ("powerpc/eeh: Report
frozen parent PE prior to child PE"). There are 2 ways to report
EEH errors: proactively polling because of 0xFF's returned from
PCI config or IO read, or interrupt driven event. We missed to
report and handle parent frozen PE prior to child frozen PE for
the later case on PowerNV platform.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Dump PCI config space for all child devices
Gavin Shan [Tue, 30 Sep 2014 02:39:08 +0000 (12:39 +1000)]
powerpc/eeh: Dump PCI config space for all child devices

The PEs can be organized as nested. Current implementation doesn't
dump PCI config space for subordinate devices of child PEs. However,
the frozen PE could be caused by those subordinate devices of its
child PEs.

The patch dumps PCI config space for all subordinate devices of the
problematic PE.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Emulate EEH recovery for VFIO devices
Gavin Shan [Tue, 30 Sep 2014 02:39:07 +0000 (12:39 +1000)]
powerpc/eeh: Emulate EEH recovery for VFIO devices

When enabling EEH functionality on passed through devices (PE)
with VFIO, the devices in the PE would be removed permanently
from guest side. In that case, the PE remains frozen state.
When returning PE to host, or restarting the guest again, we
had mechanism unfreezing the PE by clearing PESTA/B frozen
bits. However, that's not enough for some adapters, which are
indicated as following "lspci" shows. Those adapters require
hot reset on the parent bus to bring their firmware back to
workable state. Otherwise, those adaptrs won't be operative
and the host (for returning case) or the guest will fail to
load the drivers for those adapters without exception.

0000:01:00.0 Ethernet controller: Emulex Corporation OneConnect \
             10Gb NIC (be3) (rev 02)
0000:01:00.0 0200: 19a2:0710 (rev 02)
0001:03:00.0 Ethernet controller: Emulex Corporation OneConnect \
             NIC (Lancer) (rev 10)
0001:03:00.0 0200: 10df:e220 (rev 10)

The patch adds mechanism to emulate EEH recovery (for hot reset
on parent PCI bus) on 3 gates to fix the issue: open/release one
adapter of the PE, enable EEH functionality on one adapter of the
PE.

Reported-by: Murilo Fossa Vicentini <muvic@br.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Tag reset state for user owned PE
Gavin Shan [Tue, 30 Sep 2014 02:39:06 +0000 (12:39 +1000)]
powerpc/eeh: Tag reset state for user owned PE

PE would be owned by userland, which probably request PE reset
done in host side. During the reset, we should drop the PCI
config accesses to the PE with help of flag EEH_PE_RESET.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Sync OpalPciResetScope with firmware
Gavin Shan [Tue, 30 Sep 2014 02:39:05 +0000 (12:39 +1000)]
powerpc/powernv: Sync OpalPciResetScope with firmware

The names of PCI reset scopes aren't sychronized with firmware.
The patch fixes it.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/pseries: Decrease message level on EEH initialization
Gavin Shan [Tue, 30 Sep 2014 02:39:04 +0000 (12:39 +1000)]
powerpc/pseries: Decrease message level on EEH initialization

As Anton suggested, the patch decreases the message level on EEH
initialization to avoid unnecessary messages if required. Also,
we have unified hint if any of needful RTAS calls is missed, and
then we can check /proc/device-tree to figure out the missed RTAS
calls.

Suggested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Block PCI config access during reset
Gavin Shan [Tue, 30 Sep 2014 02:39:03 +0000 (12:39 +1000)]
powerpc/eeh: Block PCI config access during reset

Function pcibios_set_pcie_reset_state() can be used to do PCI
reset. PCI config access during the reset usually causes EEH
errors unexpectedly. In order to avoid the EEH error, the patch
blocks PCI config access during reset with the help of flag
EEH_PE_RESET, which is similar to what we did in EEH PE reset
path.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Use eeh_unfreeze_pe()
Gavin Shan [Tue, 30 Sep 2014 02:39:02 +0000 (12:39 +1000)]
powerpc/eeh: Use eeh_unfreeze_pe()

The patch uses eeh_unfreeze_pe() to replace the logic clearing
frozen IO and DMA, in order to simplify the code.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Unfreeze PE on enabling EEH functionality
Gavin Shan [Tue, 30 Sep 2014 02:39:01 +0000 (12:39 +1000)]
powerpc/eeh: Unfreeze PE on enabling EEH functionality

When passing through PE to guest, that's possibly in frozen
state. The driver for the pass-through devices on guest side
can't be loaded successfully as reported. We already had one
gate in eeh_dev_open() to clear PE frozen state accordingly,
but that's not enough because the function is only called at
QEMU startup for once.

The patch adds another gate in eeh_pe_set_option() so that the
PE frozen state can be cleared at QEMU restart time.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Fix improper condition in eeh_pci_enable()
Gavin Shan [Tue, 30 Sep 2014 02:39:00 +0000 (12:39 +1000)]
powerpc/eeh: Fix improper condition in eeh_pci_enable()

The function eeh_pci_enable() is called to apply various requests
to one particular PE: Enabling EEH, Disabling EEH, Enabling IO,
Enabling DMA, Freezing PE. When enabling IO or DMA on one specific
PE, we need check that IO or DMA isn't enabled previously. But
the condition used to do the check isn't completely correct because
one PE would be in DMA frozen state with workable IO path, or vice
versa.

The patch fixes the improper condition.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Clear frozen device state in time
Gavin Shan [Tue, 30 Sep 2014 02:38:59 +0000 (12:38 +1000)]
powerpc/eeh: Clear frozen device state in time

The problem was reported by Carol: In the scenario of passing mlx4
adapter to guest, EEH error could be recovered successfully. When
returning the device back to host, the driver (mlx4_core.ko)
couldn't be loaded successfully because of error number -5 (-EIO)
returned from mlx4_get_ownership(), which hits offlined PCI device.
The root cause is that we missed to put the affected devices into
normal state on clearing PE isolated state right after PE reset.

The patch fixes above issue by putting the affected devices to
normal state when clearing PE isolated state in eeh_pe_state_clear().

Cc: stable@vger.kernel.org
Reported-by: Carol L. Soto <clsoto@us.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Clear PAPR error injection registers
Gavin Shan [Tue, 30 Sep 2014 02:38:58 +0000 (12:38 +1000)]
powerpc/powernv: Clear PAPR error injection registers

The frozen state on one specific PE is probably caused by error
injection, which is done with help of PAPR error injection registers.
According to the hardware spec, those registers should be cleared
automatically after one-shot frozen PE. However, that's not always
true, at least on P7IOC of Firebird-L. So we have to clear them
before doing PE reset to avoid recursive EEH errors at recovery
stage.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Add PCI error injection debugfs entry
Mike Qiu [Tue, 30 Sep 2014 02:38:57 +0000 (12:38 +1000)]
powerpc/powernv: Add PCI error injection debugfs entry

The patch adds debugfs file (/sys/kernel/debug/powerpc/PCIxxxx/
err_injct), which accepts following formated string, to support
error injection. It will be used to support userland utility
"errinjct" in future.

  "pe_no:0:function:address:mask" - 32-bits PCI errors
  "pe_no:1:function:address:mask" - 64-bits PCI errors

Signed-off-by: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Introduce eeh_ops::err_inject
Gavin Shan [Tue, 30 Sep 2014 02:38:56 +0000 (12:38 +1000)]
powerpc/eeh: Introduce eeh_ops::err_inject

The patch introduces eeh_ops::err_inject(), which allows to inject
specified errors to indicated PE for testing purpose. The functionality
isn't support on pSeries platform. On PowerNV, the functionality
relies on OPAL API opal_pci_err_inject().

Signed-off-by: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Sync header with firmware
Gavin Shan [Tue, 30 Sep 2014 02:38:55 +0000 (12:38 +1000)]
powerpc/powernv: Sync header with firmware

The patch synchronizes firmware header file (opal.h) for PCI error
injection.

Signed-off-by: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Clear frozen state on passing device
Gavin Shan [Tue, 30 Sep 2014 02:38:54 +0000 (12:38 +1000)]
powerpc/eeh: Clear frozen state on passing device

When passing through device, its PE might have been put into frozen
state. One obvious example would be: the passed PE is forced to be
offline because of hitting maximal allowed EEH errors in userland.
In that case, the frozen state won't be cleared and then the PE is
returned back to host, which might not have chance detecting and
recovering from it.

The patch adds more check when passing through device and clear the
PE frozen state if necessary.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Reenable PCI devices after reset
Gavin Shan [Tue, 30 Sep 2014 02:38:53 +0000 (12:38 +1000)]
powerpc/eeh: Reenable PCI devices after reset

The PCI devices that have been passed through are enabled before
reset, we need restore to the enabled state after reset. Otherwise,
MMIO access might be issued to disabled devices after reset and
causes exceptional recursive EEH error.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Freeze PE before PE reset
Gavin Shan [Tue, 30 Sep 2014 02:38:52 +0000 (12:38 +1000)]
powerpc/eeh: Freeze PE before PE reset

The patch adds one more option (EEH_OPT_FREEZE_PE) to set_option()
method to proactively freeze PE, which will be issued before resetting
pass-throughed PE to drop MMIO access during reset because it's
always contributing to recursive EEH error.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Add eeh_pe_state sysfs entry
Gavin Shan [Tue, 30 Sep 2014 02:38:51 +0000 (12:38 +1000)]
powerpc/eeh: Add eeh_pe_state sysfs entry

The patch adds sysfs entry "eeh_pe_state". Reading on it returns
the PE's state while writing to it clears the frozen state. It's
used to check or clear the PE frozen state from userland for
debugging purpose.

The patch also replaces printk(KERN_WARNING ...) with pr_warn() in
eeh_sysfs.c

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Drop unused argument in eeh_check_failure()
Gavin Shan [Tue, 30 Sep 2014 02:38:50 +0000 (12:38 +1000)]
powerpc/eeh: Drop unused argument in eeh_check_failure()

eeh_check_failure() is used to check frozen state of the PE which
owns the indicated I/O address. The argument "val" of the function
isn't used. The patch drops it and return the frozen state of the
PE as expected.

Cc: Vishal Mansur <vmansur@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Enable DCACHE_WORD_ACCESS on ppc64le
Anton Blanchard [Thu, 18 Sep 2014 23:40:21 +0000 (09:40 +1000)]
powerpc: Enable DCACHE_WORD_ACCESS on ppc64le

Enable on DCACHE_WORD_ACCESS on ppc64le. It should work on
ppc64 and ppc32 but we need to do some testing first.

A somewhat reasonable testcase used to show the performance
improvement - a repeated stat of a 33 byte filename that
doesn't exist:

 #include <sys/types.h>
 #include <sys/stat.h>
 #include <unistd.h>

 #define ITERATIONS 10000000

 #define PATH "123456781234567812345678123456781"

 int main(void)
 {
  unsigned long i;
  struct stat buf;

  for (i = 0; i < ITERATIONS; i++)
  stat(PATH, &buf);

  return 0;
 }

runs 27% faster on POWER8.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: ppc64le optimised word at a time
Anton Blanchard [Thu, 18 Sep 2014 23:40:20 +0000 (09:40 +1000)]
powerpc: ppc64le optimised word at a time

Use cmpb which compares each byte in two 64 bit values and
for each matching byte places 0xff in the target and 0x00
otherwise.

A simple hash_name microbenchmark:

http://ozlabs.org/~anton/junkcode/hash_name_bench.c

shows this version to be 10-20% faster than running the x86
version on POWER8, depending on the length.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agoselftests/powerpc: Add test of load_unaligned_zero_pad()
Michael Ellerman [Thu, 25 Sep 2014 06:45:11 +0000 (16:45 +1000)]
selftests/powerpc: Add test of load_unaligned_zero_pad()

It is a rarely exercised case, so we want to have a test to ensure it
works as required.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Implement load_unaligned_zeropad
Anton Blanchard [Thu, 18 Sep 2014 23:40:19 +0000 (09:40 +1000)]
powerpc: Implement load_unaligned_zeropad

Implement a bi-arch and bi-endian version of load_unaligned_zeropad.

Since the fallback case is so rare, a userspace test harness was used
to test this on ppc64le, ppc64 and ppc32:

http://ozlabs.org/~anton/junkcode/test_load_unaligned_zeropad.c

It uses mprotect to force a SEGV across a page boundary, and a SEGV
handler to lookup the exception tables and run the fixup routine.
It also compares the result against a normal load.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: pci-ioda: Use a single function to emit logging messages
Joe Perches [Sun, 21 Sep 2014 17:55:06 +0000 (10:55 -0700)]
powerpc: pci-ioda: Use a single function to emit logging messages

No need for 3 functions when a single one will do.

Modify the function declaring macros to call the single function.

Reduces object code size a little:

$ size arch/powerpc/platforms/powernv/pci-ioda.o*
   text    data     bss     dec     hex filename
  22303    1073    6680   30056    7568 arch/powerpc/platforms/powernv/pci-ioda.o.new
  22840    1121    6776   30737    7811 arch/powerpc/platforms/powernv/pci-ioda.o.old

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: pci-ioda: Remove unnecessary return value from printk
Joe Perches [Sun, 21 Sep 2014 17:55:05 +0000 (10:55 -0700)]
powerpc: pci-ioda: Remove unnecessary return value from printk

The return value is unnecessary and unused, so make the functions
void instead of int.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/eeh: Fix kernel crash when passing through VF
Wei Yang [Wed, 17 Sep 2014 02:48:26 +0000 (10:48 +0800)]
powerpc/eeh: Fix kernel crash when passing through VF

When doing vfio passthrough a VF, the kernel will crash with following
message:

[  442.656459] Unable to handle kernel paging request for data at address 0x00000060
[  442.656593] Faulting instruction address: 0xc000000000038b88
[  442.656706] Oops: Kernel access of bad area, sig: 11 [#1]
[  442.656798] SMP NR_CPUS=1024 NUMA PowerNV
[  442.656890] Modules linked in: vfio_pci mlx4_core nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6t_REJECT xt_conntrack bnep bluetooth rfkill ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw tg3 nfsd be2net nfs_acl ses lockd ptp enclosure pps_core kvm_hv kvm_pr shpchp binfmt_misc kvm sunrpc uinput lpfc scsi_transport_fc ipr scsi_tgt [last unloaded: mlx4_core]
[  442.658152] CPU: 40 PID: 14948 Comm: qemu-system-ppc Not tainted 3.10.42yw-pkvm+ #37
[  442.658219] task: c000000f7e2a9a00 ti: c000000f6dc3c000 task.ti: c000000f6dc3c000
[  442.658287] NIP: c000000000038b88 LR: c0000000004435a8 CTR: c000000000455bc0
[  442.658352] REGS: c000000f6dc3f580 TRAP: 0300   Not tainted  (3.10.42yw-pkvm+)
[  442.658419] MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI>  CR: 28004882  XER: 20000000
[  442.658577] CFAR: c00000000000908c DAR: 0000000000000060 DSISR: 40000000 SOFTE: 1
GPR00: c0000000004435a8 c000000f6dc3f800 c0000000012b1c10 c00000000da24000
GPR04: 0000000000000003 0000000000001004 00000000000015b3 000000000000ffff
GPR08: c00000000127f5d8 0000000000000000 000000000000ffff 0000000000000000
GPR12: c000000000068078 c00000000fdd6800 000001003c320c80 000001003c3607f0
GPR16: 0000000000000001 00000000105480c8 000000001055aaa8 000001003c31ab18
GPR20: 000001003c10fb40 000001003c360ae8 000000001063bcf0 000000001063bdb0
GPR24: 000001003c15ed70 0000000010548f40 c000001fe5514c88 c000001fe5514cb0
GPR28: c00000000da24000 0000000000000000 c00000000da24000 0000000000000003
[  442.659471] NIP [c000000000038b88] .pcibios_set_pcie_reset_state+0x28/0x130
[  442.659530] LR [c0000000004435a8] .pci_set_pcie_reset_state+0x28/0x40
[  442.659585] Call Trace:
[  442.659610] [c000000f6dc3f800] [00000000000719e0] 0x719e0 (unreliable)
[  442.659677] [c000000f6dc3f880] [c0000000004435a8] .pci_set_pcie_reset_state+0x28/0x40
[  442.659757] [c000000f6dc3f900] [c000000000455bf8] .reset_fundamental+0x38/0x80
[  442.659835] [c000000f6dc3f980] [c0000000004562a8] .pci_dev_specific_reset+0xa8/0xf0
[  442.659913] [c000000f6dc3fa00] [c0000000004448c4] .__pci_dev_reset+0x44/0x430
[  442.659980] [c000000f6dc3fab0] [c000000000444d5c] .pci_reset_function+0x7c/0xc0
[  442.660059] [c000000f6dc3fb30] [d00000001c141ab8] .vfio_pci_open+0xe8/0x2b0 [vfio_pci]
[  442.660139] [c000000f6dc3fbd0] [c000000000586c30] .vfio_group_fops_unl_ioctl+0x3a0/0x630
[  442.660219] [c000000f6dc3fc90] [c000000000255fbc] .do_vfs_ioctl+0x4ec/0x7c0
[  442.660286] [c000000f6dc3fd80] [c000000000256364] .SyS_ioctl+0xd4/0xf0
[  442.660354] [c000000f6dc3fe30] [c000000000009e54] syscall_exit+0x0/0x98
[  442.660420] Instruction dump:
[  442.660454] 4bfffce9 4bfffee4 7c0802a6 fbc1fff0 fbe1fff8 f8010010 f821ff81 7c7e1b78
[  442.660566] 7c9f2378 60000000 60000000 e93e02c8 <e86900602fa30000 41de00c4 2b9f0002
[  442.660679] ---[ end trace a64ac9546bcf0328 ]---
[  442.660724]

The reason is current VF is not EEH enabled.

This patch introduces a macro to convert eeh_dev to eeh_pe. By doing so, it
will prevent converting with NULL pointer.

Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
CC: Michael Ellerman <mpe@ellerman.id.au>
V3 -> V4:
   1. move the macro definition from include/linux/pci.h to
      arch/powerpc/include/asm/eeh.h

V2 -> V3:
   1. rebased on 3.17-rc4
   2. introduce a macro
   3. use this macro in several other places

V1 -> V2:
   1. code style and patch subject adjustment

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/mm: Unindent htab_dt_scan_page_sizes()
Michael Ellerman [Thu, 7 Aug 2014 07:26:33 +0000 (17:26 +1000)]
powerpc/mm: Unindent htab_dt_scan_page_sizes()

We can unindent the bulk of htab_dt_scan_page_sizes() by returning early
if the property is not found. That is nice in and of itself, but also
has the advantage of making it clear that we always return success once
we have found the ibm,segment-page-sizes property.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/ppc64: Print CPU/MMU/FW features at boot
Michael Ellerman [Wed, 6 Aug 2014 09:08:22 +0000 (19:08 +1000)]
powerpc/ppc64: Print CPU/MMU/FW features at boot

"Helps debug funky firmware issues".

After:
  Starting Linux PPC64 #108 SMP Wed Aug 6 19:04:51 EST 2014
  -----------------------------------------------------
  ppc64_pft_size    = 0x1a
  phys_mem_size     = 0x200000000
  cpu_features      = 0x17fc7a6c18500249
    possible        = 0x1fffffff18700649
    always          = 0x0000000000000040
  cpu_user_features = 0xdc0065c2 0xee000000
  mmu_features      = 0x5a000001
  firmware_features = 0x00000001405a440b
  htab_hash_mask    = 0x7ffff
  -----------------------------------------------------

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/ppc64: Clean up the boot-time settings display
Michael Ellerman [Wed, 6 Aug 2014 09:08:21 +0000 (19:08 +1000)]
powerpc/ppc64: Clean up the boot-time settings display

At boot we display a bunch of low level settings which can be useful to
know, and can help to spot bugs when things are fundamentally
misconfigured.

At the moment they are very widely spaced, so that we can accommodate
the line:

  ppc64_caches.dcache_line_size = 0xYY

But we only print that line when the cache line size is not 128, ie.
almost never, so it just makes the display look odd usually.

The ppc64_caches prefix is redundant so remove it, which means we can
align things a bit closer for the common case. While we're there
replace the last use of camelCase (physicalMemorySize), and use
phys_mem_size.

Before:
  Starting Linux PPC64 #104 SMP Wed Aug 6 18:41:34 EST 2014
  -----------------------------------------------------
  ppc64_pft_size                = 0x1a
  physicalMemorySize            = 0x200000000
  ppc64_caches.dcache_line_size = 0xf0
  ppc64_caches.icache_line_size = 0xf0
  htab_address                  = 0xdeadbeef
  htab_hash_mask                = 0x7ffff
  physical_start                = 0xf000bar
  -----------------------------------------------------

After:
  Starting Linux PPC64 #103 SMP Wed Aug 6 18:38:04 EST 2014
  -----------------------------------------------------
  ppc64_pft_size    = 0x1a
  phys_mem_size     = 0x200000000
  dcache_line_size  = 0xf0
  icache_line_size  = 0xf0
  htab_address      = 0xdeadbeef
  htab_hash_mask    = 0x7ffff
  physical_start    = 0xf000bar
  -----------------------------------------------------

This patch is final, no bike shedding ;)

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Fix build failure when CONFIG_USB=y
Pranith Kumar [Thu, 21 Aug 2014 13:16:04 +0000 (09:16 -0400)]
powerpc: Fix build failure when CONFIG_USB=y

We are enabling USB unconditionally which results in following build failure

drivers/built-in.o: In function `tb_drom_read':
(.text+0x1b62b70): undefined reference to `usb_speed_string'
make: *** [vmlinux] Error

Enable USB only if USB_SUPPORT is set to avoid such failures

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Acked-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Fix build failure on 44x
Pranith Kumar [Thu, 21 Aug 2014 13:04:31 +0000 (09:04 -0400)]
powerpc: Fix build failure on 44x

Fix the following build failure

drivers/built-in.o: In function `nhi_init':
nhi.c:(.init.text+0x63390): undefined reference to `ehci_init_driver'

by adding a dependency on USB_EHCI_HCD which supplies the ehci_init_driver().

Also we need to depend on USB_OHCI_HCD similarly

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Acked-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: some changes in numa_setup_cpu()
Li Zhong [Wed, 27 Aug 2014 09:34:01 +0000 (17:34 +0800)]
powerpc: some changes in numa_setup_cpu()

this patches changes some error handling logics in numa_setup_cpu(),
when cpu node is not found, so:

if the cpu is possible, but not present, -1 is kept in numa_cpu_lookup_table,
so later, if the cpu is added, we could set correct numa information for it.

if the cpu is present, then we set the first online node to
numa_cpu_lookup_table instead of 0 ( in case 0 might not be an online node? )

Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Only set numa node information for present cpus at boottime
Li Zhong [Wed, 27 Aug 2014 09:34:00 +0000 (17:34 +0800)]
powerpc: Only set numa node information for present cpus at boottime

As Nish suggested, it makes more sense to init the numa node informatiion
for present cpus at boottime, which could also avoid WARN_ON(1) in
numa_setup_cpu().

With this change, we also need to change the smp_prepare_cpus() to set up
numa information only on present cpus.

For those possible, but not present cpus, their numa information
will be set up after they are started, as the original code did before commit
2fabf084b6ad.

Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Tested-by: Cyril Bur <cyril.bur@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Fix warning reported by verify_cpu_node_mapping()
Li Zhong [Wed, 27 Aug 2014 09:33:59 +0000 (17:33 +0800)]
powerpc: Fix warning reported by verify_cpu_node_mapping()

With commit 2fabf084b6ad ("powerpc: reorder per-cpu NUMA information's
initialization"), during boottime, cpu_numa_callback() is called
earlier(before their online) for each cpu, and verify_cpu_node_mapping()
uses cpu_to_node() to check whether siblings are in the same node.

It skips the checking for siblings that are not online yet. So the only
check done here is for the bootcpu, which is online at that time. But
the per-cpu numa_node cpu_to_node() uses hasn't been set up yet (which
will be set up in smp_prepare_cpus()).

So I saw something like following reported:
[    0.000000] CPU thread siblings 1/2/3 and 0 don't belong to the same
node!

As we don't actually do the checking during this early stage, so maybe
we could directly call numa_setup_cpu() in do_init_bootmem().

Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Implement emulation of string loads and stores
Paul Mackerras [Tue, 2 Sep 2014 04:35:09 +0000 (14:35 +1000)]
powerpc: Implement emulation of string loads and stores

The size field of the op.type word is now the total number of bytes
to be loaded or stored.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Emulate icbi, mcrf and conditional-trap instructions
Paul Mackerras [Tue, 2 Sep 2014 04:35:08 +0000 (14:35 +1000)]
powerpc: Emulate icbi, mcrf and conditional-trap instructions

This extends the instruction emulation done by analyse_instr() and
emulate_step() to handle a few more instructions that are found in
the kernel.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Split out instruction analysis part of emulate_step()
Paul Mackerras [Tue, 2 Sep 2014 04:35:07 +0000 (14:35 +1000)]
powerpc: Split out instruction analysis part of emulate_step()

This splits out the instruction analysis part of emulate_step() into
a separate analyse_instr() function, which decodes the instruction,
but doesn't execute any load or store instructions.  It does execute
integer instructions and branches which can be executed purely by
updating register values in the pt_regs struct.  For other instructions,
it returns the instruction type and other details in a new
instruction_op struct.  emulate_step() then uses that information
to execute loads, stores, cache operations, mfmsr, mtmsr[d], and
(on 64-bit) sc instructions.

The reason for doing this is so that the KVM code can use it instead
of having its own separate instruction emulation code.  Possibly the
alignment interrupt handler could also use this.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Check flat device tree version at boot
Michael Ellerman [Thu, 28 Aug 2014 08:40:47 +0000 (18:40 +1000)]
powerpc: Check flat device tree version at boot

In commit e6a6928c3ea1 "of/fdt: Convert FDT functions to use libfdt",
the kernel stopped supporting old flat device tree formats. The minimum
supported version is now 0x10.

There was a checking function added, early_init_dt_verify(), but it's
not called on powerpc.

The result is, if you boot with an old flat device tree, the kernel will
fail to parse it correctly, think you have no memory etc. and hilarity
ensues.

We can't really fix it, but we can at least catch the fact that the
device tree is in an unsupported format and panic(). We can't call
BUG(), it's too early.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Don't call generic code on offline cpus
Paul Mackerras [Tue, 2 Sep 2014 04:23:16 +0000 (14:23 +1000)]
powerpc/powernv: Don't call generic code on offline cpus

On PowerNV platforms, when a CPU is offline, we put it into nap mode.
It's possible that the CPU wakes up from nap mode while it is still
offline due to a stray IPI.  A misdirected device interrupt could also
potentially cause it to wake up.  In that circumstance, we need to clear
the interrupt so that the CPU can go back to nap mode.

In the past the clearing of the interrupt was accomplished by briefly
enabling interrupts and allowing the normal interrupt handling code
(do_IRQ() etc.) to handle the interrupt.  This has the problem that
this code calls irq_enter() and irq_exit(), which call functions such
as account_system_vtime() which use RCU internally.  Use of RCU is not
permitted on offline CPUs and will trigger errors if RCU checking is
enabled.

To avoid calling into any generic code which might use RCU, we adopt
a different method of clearing interrupts on offline CPUs.  Since we
are on the PowerNV platform, we know that the system interrupt
controller is a XICS being driven directly (i.e. not via hcalls) by
the kernel.  Hence this adds a new icp_native_flush_interrupt()
function to the native-mode XICS driver and arranges to call that
when an offline CPU is woken from nap.  This new function reads the
interrupt from the XICS.  If it is an IPI, it clears the IPI; if it
is a device interrupt, it prints a warning and disables the source.
Then it does the end-of-interrupt processing for the interrupt.

The other thing that briefly enabling interrupts did was to check and
clear the irq_happened flag in this CPU's PACA.  Therefore, after
flushing the interrupt from the XICS, we also clear all bits except
the PACA_IRQ_HARD_DIS (interrupts are hard disabled) bit from the
irq_happened flag.  The PACA_IRQ_HARD_DIS flag is set by power7_nap()
and is left set to indicate that interrupts are hard disabled.  This
means we then have to ignore that flag in power7_nap(), which is
reasonable since it doesn't indicate that any interrupt event needs
servicing.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Use CONFIG_ARCH_HAS_FAST_MULTIPLIER
Anton Blanchard [Tue, 16 Sep 2014 00:49:14 +0000 (10:49 +1000)]
powerpc: Use CONFIG_ARCH_HAS_FAST_MULTIPLIER

I ran some tests to compare hash_64 using shifts and multiplies.
The results:

POWER6: ~2x slower
POWER7: ~2x faster
POWER8: ~2x faster

Now we have a proper config option, select
CONFIG_ARCH_HAS_FAST_MULTIPLIER on POWER7 and POWER8.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Add POWER8 CPU selection
Anton Blanchard [Tue, 16 Sep 2014 00:47:49 +0000 (10:47 +1000)]
powerpc: Add POWER8 CPU selection

This allows the user to build a kernel targeted at POWER8
(ie gcc -mcpu=power8).

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopseries: Fix endian issues in cpu hot-removal
Thomas Falcon [Fri, 12 Sep 2014 19:11:42 +0000 (14:11 -0500)]
pseries: Fix endian issues in cpu hot-removal

When removing a cpu, this patch makes sure that values
gotten from or passed to firmware are in the correct
endian format.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopseries: Fix endian issues in onlining cpu threads
Thomas Falcon [Fri, 12 Sep 2014 19:11:41 +0000 (14:11 -0500)]
pseries: Fix endian issues in onlining cpu threads

The ibm,ppc-interrupt-server#s property is in big endian format.
These values need to be converted when used by little endian
architectures.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Simplify symbol check in prom_init_check.sh
Andreas Schwab [Sat, 13 Sep 2014 08:20:17 +0000 (10:20 +0200)]
powerpc: Simplify symbol check in prom_init_check.sh

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: make of_device_ids const
Uwe Kleine-König [Wed, 10 Sep 2014 19:56:38 +0000 (21:56 +0200)]
powerpc: make of_device_ids const

of_device_ids (i.e. compatible strings and the respective data) are not
supposed to change at runtime. All functions working with of_device_ids
provided by <linux/of.h> work with const of_device_ids. This allows to
mark all struct of_device_id const, too.

While touching these line also put the __init annotation at the right
position where necessary.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/jump_label: use HAVE_JUMP_LABEL?
Zhouyi Zhou [Thu, 21 Aug 2014 02:41:23 +0000 (10:41 +0800)]
powerpc/jump_label: use HAVE_JUMP_LABEL?

CONFIG_JUMP_LABEL doesn't ensure HAVE_JUMP_LABEL, if it
is not the case use maintainers's own mutex to guard
the modification of global values.

Signed-off-by: Zhouyi Zhou <yizhouzhou@ict.ac.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Export dcr_ind_lock to fix build error
Pranith Kumar [Wed, 20 Aug 2014 03:24:15 +0000 (23:24 -0400)]
powerpc: Export dcr_ind_lock to fix build error

Fix build error caused by missing export:

ERROR: "dcr_ind_lock" [drivers/net/ethernet/ibm/emac/ibm_emac.ko] undefined!

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Move htab_remove_mapping function prototype into header file
Anton Blanchard [Tue, 19 Aug 2014 22:55:21 +0000 (08:55 +1000)]
powerpc: Move htab_remove_mapping function prototype into header file

A recent patch added a function prototype for htab_remove_mapping in
c code. Fix it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Remove stale function prototypes
Anton Blanchard [Tue, 19 Aug 2014 22:55:20 +0000 (08:55 +1000)]
powerpc: Remove stale function prototypes

There were a number of prototypes for functions that no longer
exist. Remove them.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Ensure global functions include their prototype
Anton Blanchard [Tue, 19 Aug 2014 22:55:19 +0000 (08:55 +1000)]
powerpc: Ensure global functions include their prototype

Fix a number of places where global functions were not including
their prototype. This ensures the prototype and the function match.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Make a bunch of things static
Anton Blanchard [Tue, 19 Aug 2014 22:55:18 +0000 (08:55 +1000)]
powerpc: Make a bunch of things static

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Separate ppc32 symbol exports into ppc_ksyms_32.c
Anton Blanchard [Tue, 19 Aug 2014 22:00:05 +0000 (08:00 +1000)]
powerpc: Separate ppc32 symbol exports into ppc_ksyms_32.c

Simplify things considerably by moving all the ppc32 specific
symbol exports into its own file.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Move lib symbol exports into arch/powerpc/lib/ppc_ksyms.c
Anton Blanchard [Tue, 19 Aug 2014 22:00:04 +0000 (08:00 +1000)]
powerpc: Move lib symbol exports into arch/powerpc/lib/ppc_ksyms.c

Move the lib symbol exports closer to their function definitions

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Remove unused 32bit symbol exports
Anton Blanchard [Tue, 19 Aug 2014 22:00:03 +0000 (08:00 +1000)]
powerpc: Remove unused 32bit symbol exports

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Move more symbol exports next to function definitions
Anton Blanchard [Tue, 19 Aug 2014 22:00:02 +0000 (08:00 +1000)]
powerpc: Move more symbol exports next to function definitions

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Move via-cuda symbol exports next to function definitions
Anton Blanchard [Tue, 19 Aug 2014 22:00:01 +0000 (08:00 +1000)]
powerpc: Move via-cuda symbol exports next to function definitions

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Move adb symbol exports next to function definitions
Anton Blanchard [Tue, 19 Aug 2014 22:00:00 +0000 (08:00 +1000)]
powerpc: Move adb symbol exports next to function definitions

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Check OPAL dump calls exist before using
Michael Neuling [Tue, 19 Aug 2014 04:48:02 +0000 (14:48 +1000)]
powerpc/powernv: Check OPAL dump calls exist before using

Check that the OPAL_DUMP_READ token exists before initalising the elog
infrastructure.

This avoids littering the OPAL console with:
  "OPAL: Called with bad token 91"

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Check OPAL elog calls exist before using
Michael Neuling [Tue, 19 Aug 2014 04:48:01 +0000 (14:48 +1000)]
powerpc/powernv: Check OPAL elog calls exist before using

Check that the OPAL_ELOG_READ token exists before initalising the elog
infrastructure.

This avoids littering the OPAL console with:
  "OPAL: Called with bad token 74"

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Check OPAL RTC calls exists before using
Michael Neuling [Tue, 19 Aug 2014 04:48:00 +0000 (14:48 +1000)]
powerpc/powernv: Check OPAL RTC calls exists before using

Check that the OPAL_RTC_READ token exists before we use the OPAL RTC.

Refactors the code a little to merge error paths.

This avoids littering the OPAL console with:
  "OPAL: Called with bad token 3".

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Add OPAL check token call
Michael Neuling [Tue, 19 Aug 2014 04:47:59 +0000 (14:47 +1000)]
powerpc/powernv: Add OPAL check token call

Currently there is no way to generically check if an OPAL call exists or not
from the host kernel.

This adds an OPAL call opal_check_token() which tells you if the given token is
present in OPAL or not.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc: Fix build error with CONFIG_PCI=n
Pranith Kumar [Mon, 18 Aug 2014 21:13:41 +0000 (17:13 -0400)]
powerpc: Fix build error with CONFIG_PCI=n

Fix ppc 32 build failure as reported here:

http://kisskb.ellerman.id.au/kisskb/buildresult/11663513/

The error is as follows:

arch/powerpc/include/asm/floppy.h:142:20: error: 'isa_bridge_pcidev' undeclared
(first use in this function)

This is happening since floppy.o is enabled by BLK_DEV_FD which depends on
ARCH_MAY_HAVE_PC_FDC which is in-turn enabled if PPC_PSERIES=n.

The following commit changes the dependency so that ARCH_MAY_HAVE_PC_FDC is
dependent exclusively on PCI since otherwise it will not compile.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
CC: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/boot: Don't install zImage.* from make install
Tony Breeds [Thu, 14 Aug 2014 07:05:04 +0000 (17:05 +1000)]
powerpc/boot: Don't install zImage.* from make install

in commit 29f1aff2c (powerpc: Copy bootable images in the default
install script) we changed to copying all the built boot targets based
on the assumption that it's backwards compatible.  It turns out that
debian devived installkernel scripts will barf if not given exactly 4
args.

This change reverts make install to just install the vmlinux (we can
change the dfault in a seperate patch) and introduces a new make
zInstall which works with a more flexible installkernel script.

Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/powernv: Improve error messages in dump code
Vasant Hegde [Thu, 14 Aug 2014 06:46:39 +0000 (12:16 +0530)]
powerpc/powernv: Improve error messages in dump code

Presently we only support initiating Service Processor dump from host.
Hence update sysfs message. Also update couple of other error/info
messages.

Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agopowerpc/pseries: Drop unnecessary continue
Himangi Saraogi [Wed, 13 Aug 2014 09:18:47 +0000 (14:48 +0530)]
powerpc/pseries: Drop unnecessary continue

Continue is not needed at the bottom of a loop.

The Coccinelle semantic patch implementing this change is:

@@
@@

for (...;...;...) {
  ...
  if (...) {
    ...
-   continue;
  }
}

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
10 years agoRevert "powerpc/fsl_msi: spread msi ints across different MSIRs"
Scott Wood [Fri, 19 Sep 2014 20:20:36 +0000 (15:20 -0500)]
Revert "powerpc/fsl_msi: spread msi ints across different MSIRs"

This reverts commit c822e73731fce3b49a4887140878d084d8a44c08.

This commit conflicted with a bitmap allocator change that partially
accomplishes the same thing, but which does so more correctly.  Revert
this one until it can be respun on top of the correct change.

Signed-off-by: Scott Wood <scottwood@freescale.com>
10 years agopowerpc/mm: Use common paging_init() for NUMA
Scott Wood [Thu, 18 Sep 2014 19:05:02 +0000 (14:05 -0500)]
powerpc/mm: Use common paging_init() for NUMA

Commit 1c98025c6c95bc057a25e2c6596de23288c68160 "powerpc: Dynamic DMA
zone limits" updated how zones are created in paging_init(), but missed
the NUMA version of paging_init().  This was noticed via a linker
error, since dma_pfn_limit_to_zone() was, like the non-NUMA
paging_init(), limited by #ifndef CONFIG_NEED_MULTIPLE_NODES.

It turns out that the NUMA paging_init() was not actually doing
anything different from the standard paging_init(), other than a couple
debug prints, a couple 32-bit-only ifdef sections, and a call to
mark_nonram_nosave().  It's not clear whether mark_nonram_nosave() is
inherently wrong to do for NUMA, or just not useful on targets that
have NUMA, but for now I'm preserving the existing behavior.

Fixes: 1c98025c6c9 "powerpc: Dynamic DMA zone limits"
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Scott Wood <scottwood@freescale.com>
10 years agopowerpc/85xx/defconfig: Remove duplicate CONFIG_RTC_DRV_DS1307
Scott Wood [Wed, 17 Sep 2014 00:47:00 +0000 (19:47 -0500)]
powerpc/85xx/defconfig: Remove duplicate CONFIG_RTC_DRV_DS1307

Commit a95e8c28b3dc "powerpc/defconfig: update RTC support" duplicated
the CONFIG_RTC_DRV_DS1307 symbol in mpc85xx_defconfig and
mpc85xx_smp_defconfig, resulting in this:

arch/powerpc/configs/mpc85xx_smp_defconfig:217:warning: override: reassigning to symbol RTC_DRV_DS1307

Fixes: a95e8c28b3dc "powerpc/defconfig: update RTC support"
Cc: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
10 years agopowerpc: dts: t208x: Change T208x USB controller version
Nikhil Badola [Thu, 21 Aug 2014 10:31:30 +0000 (16:01 +0530)]
powerpc: dts: t208x: Change T208x USB controller version

Change USB controller version to 2.5 in compatible string for T2080/T2081

Signed-off-by: Nikhil Badola <nikhil.badola@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
10 years agoLinux 3.17-rc5
Linus Torvalds [Mon, 15 Sep 2014 00:50:12 +0000 (17:50 -0700)]
Linux 3.17-rc5

10 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Linus Torvalds [Mon, 15 Sep 2014 00:37:36 +0000 (17:37 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/viro/vfs

Pull vfs fixes from Al Viro:
 "double iput() on failure exit in lustre, racy removal of spliced
  dentries from ->s_anon in __d_materialise_dentry() plus a bunch of
  assorted RCU pathwalk fixes"

The RCU pathwalk fixes end up fixing a couple of cases where we
incorrectly dropped out of RCU walking, due to incorrect initialization
and testing of the sequence locks in some corner cases.  Since dropping
out of RCU walk mode forces the slow locked accesses, those corner cases
slowed down quite dramatically.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  be careful with nd->inode in path_init() and follow_dotdot_rcu()
  don't bugger nd->seq on set_root_rcu() from follow_dotdot_rcu()
  fix bogus read_seqretry() checks introduced in b37199e
  move the call of __d_drop(anon) into __d_materialise_unique(dentry, anon)
  [fix] lustre: d_make_root() does iput() on dentry allocation failure

10 years agovfs: avoid non-forwarding large load after small store in path lookup
Linus Torvalds [Mon, 15 Sep 2014 00:28:32 +0000 (17:28 -0700)]
vfs: avoid non-forwarding large load after small store in path lookup

The performance regression that Josef Bacik reported in the pathname
lookup (see commit 99d263d4c5b2 "vfs: fix bad hashing of dentries") made
me look at performance stability of the dcache code, just to verify that
the problem was actually fixed.  That turned up a few other problems in
this area.

There are a few cases where we exit RCU lookup mode and go to the slow
serializing case when we shouldn't, Al has fixed those and they'll come
in with the next VFS pull.

But my performance verification also shows that link_path_walk() turns
out to have a very unfortunate 32-bit store of the length and hash of
the name we look up, followed by a 64-bit read of the combined hash_len
field.  That screws up the processor store to load forwarding, causing
an unnecessary hickup in this critical routine.

It's caused by the ugly calling convention for the "hash_name()"
function, and easily fixed by just making hash_name() fill in the whole
'struct qstr' rather than passing it a pointer to just the hash value.

With that, the profile for this function looks much smoother.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
10 years agoMerge branch 'parisc-3.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...
Linus Torvalds [Sun, 14 Sep 2014 19:28:08 +0000 (12:28 -0700)]
Merge branch 'parisc-3.17-1' of git://git./linux/kernel/git/deller/parisc-linux

Pull parisc updates from Helge Deller:
 "The most important patch is a new Light Weigth Syscall (LWS) for 8,
  16, 32 and 64 bit atomic CAS operations which is required in order to
  be able to implement the atomic gcc builtins on our platform.

  Other than that, we wire up the seccomp, getrandom and memfd_create
  syscalls, fixes a minor off-by-one bug and a wrong printk string"

* 'parisc-3.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Implement new LWS CAS supporting 64 bit operations.
  parisc: Wire up seccomp, getrandom and memfd_create syscalls
  parisc: dino: fix %d confusingly prefixed with 0x in format string
  parisc: sys_hpux: NUL terminator is one past the end

10 years agobe careful with nd->inode in path_init() and follow_dotdot_rcu()
Al Viro [Sun, 14 Sep 2014 01:59:43 +0000 (21:59 -0400)]
be careful with nd->inode in path_init() and follow_dotdot_rcu()

in the former we simply check if dentry is still valid after picking
its ->d_inode; in the latter we fetch ->d_inode in the same places
where we fetch dentry and its ->d_seq, under the same checks.

Cc: stable@vger.kernel.org # 2.6.38+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
10 years agodon't bugger nd->seq on set_root_rcu() from follow_dotdot_rcu()
Al Viro [Sun, 14 Sep 2014 01:55:46 +0000 (21:55 -0400)]
don't bugger nd->seq on set_root_rcu() from follow_dotdot_rcu()

return the value instead, and have path_init() do the assignment.  Broken by
"vfs: Fix absolute RCU path walk failures due to uninitialized seq number",
which was Cc-stable with 2.6.38+ as destination.  This one should go where
it went.

To avoid dummy value returned in case when root is already set (it would do
no harm, actually, since the only caller that doesn't ignore the return value
is guaranteed to have nd->root *not* set, but it's more obvious that way),
lift the check into callers.  And do the same to set_root(), to keep them
in sync.

Cc: stable@vger.kernel.org # 2.6.38+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
10 years agoMerge tag 'ntb-3.17' of git://github.com/jonmason/ntb
Linus Torvalds [Sun, 14 Sep 2014 17:54:12 +0000 (10:54 -0700)]
Merge tag 'ntb-3.17' of git://github.com/jonmason/ntb

Pull ntb driver bugfixes from Jon Mason:
 "NTB driver fixes for queue spread and buffer alignment.  Also, update
  to MAINTAINERS to reflect new e-mail address"

* tag 'ntb-3.17' of git://github.com/jonmason/ntb:
  ntb: Add alignment check to meet hardware requirement
  MAINTAINERS: update NTB info
  NTB: correct the spread of queues over mw's

10 years agoMerge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 14 Sep 2014 17:37:10 +0000 (10:37 -0700)]
Merge branch 'irq-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull ARM irq chip fixes from Thomas Gleixner:
 "Another pile of ARM specific irq chip fixlets:

   - off by one bugs in the crossbar driver
   - missing annotations
   - a bunch of "make it compile" updates

  I pulled the lot today from Jason, but it has been in -next for at
  least a week"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip: gic-v3: Declare rdist as __percpu pointer to __iomem pointer
  irqchip: gic: Make gic_default_routable_irq_domain_ops static
  irqchip: exynos-combiner: Fix compilation error on ARM64
  irqchip: crossbar: Off by one bugs in init
  irqchip: gic-v3: Tag all low level accessors __maybe_unused
  irqchip: gic-v3: Only define gic_peek_irq() when building SMP

10 years agoMerge tag 'irqchip-urgent-3.17' of git://git.infradead.org/users/jcooper/linux into...
Thomas Gleixner [Sun, 14 Sep 2014 13:19:19 +0000 (15:19 +0200)]
Merge tag 'irqchip-urgent-3.17' of git://git.infradead.org/users/jcooper/linux into irq/urgent

irqchip fixes for v3.17 from Jason Cooper

 - GIC/GICV3: Various fixlets
 - crossbar: Fix off-by-one bug
 - exynos-combiner: Fix arm64 build error

10 years agontb: Add alignment check to meet hardware requirement
Dave Jiang [Thu, 28 Aug 2014 20:53:02 +0000 (13:53 -0700)]
ntb: Add alignment check to meet hardware requirement

The NTB translate register must have the value to be BAR size aligned.
This alignment check make sure that the DMA memory allocated has the
proper alignment. Another requirement for NTB to function properly with
memory window BAR size greater or equal to 4M is to use the CMA feature
in 3.16 kernel with the appropriate CONFIG_CMA_ALIGNMENT and
CONFIG_CMA_SIZE_MBYTES set.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>