Merge some Freescale updates from Scott Wood

If CONFIG_E500 is enabled, the compilation flags are updated
specifying the target core -mcpu=e5500/e500mc/8540
Also remove -Wa,-me500, being incompatible with -mcpu=e5500/e6500
The assembler option is redundant if the -mcpu= flag is set.
The patch fixes the kernel compilation problem for e5500/e6500
when using gcc option -mcpu=e5500/e6500.
Signed-off-by: NCatalin Udma <catalin.udma@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

When using recent udev, the /dev node mount requires CONFIG_DEVTMPFS_MOUNT
is enabled in Kernel. The patch enables the option in defconfig of Freescale
QorIQ targets.

Changed defconfig list:
   arch/powerpc/configs/85xx/p1023rds_defconfig
   arch/powerpc/configs/corenet32_smp_defconfig
   arch/powerpc/configs/corenet64_smp_defconfig
   arch/powerpc/configs/mpc85xx_smp_defconfig
   arch/powerpc/configs/mpc85xx_defconfig
   arch/powerpc/configs/mpc83xx_defconfig
Signed-off-by: NZhenhua Luo <zhenhua.luo@freescale.com>
[scottwood@freescale.com: added mpc83xx and non-smp mpc85xx]
Signed-off-by: NScott Wood <scottwood@freescale.com>

For Freescale powerpc platform, the PCI-e bus number uses the reassign mode
by default. It means the second PCI-e controller's hose->first_busno is the
first controller's last bus number adding 1. For some hotpluged device(or
controlled by FPGA), the device is linked to PCI-e slot at linux runtime.
It needs rescan for the system to add it and driver it to work. It successes
to rescan the device linked to the first PCI-e controller's slot, but fails to
rescan the device linked to the second PCI-e controller's slot. The cause is
that the bus->number is reset to 0, which isn't equal to the hose->first_busno
for the second controller checking PCI-e link. So it doesn't really check the
PCI-e link status, the link status is always no_link. The device won't be
really rescaned. Reset the bus->number to hose->first_busno in the function
fsl_pcie_check_link(), it will do the real checking PCI-e link status for the
second controller, the device will be rescaned.
Signed-off-by: NYuanquan Chen <Yuanquan.Chen@freescale.com>
Tested-by: NRojhalat Ibrahim <imr@rtschenk.de>
Signed-off-by: NScott Wood <scottwood@freescale.com>

This function contains all the stuff we need to check if SWIOTLB
should be enabled or not. So it is more convenient to enable
the SWIOTLB here than later.
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

The (1ull << mem_log) is never greater than mem unless mem_log++;
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

The function pci_devs_phb_init is invoked more earlier than we really
probe the pci controller, so it does nothing at all. And we also don't
need the pci_dn stuff for the fsl powerpc64 boards, just remove it.

It also seems that we don't support ISA on all the current corenet ds
boards. So picking a primary bus seems useless, remove that function
too.
Signed-off-by: NKevin Hao <haokexin@gmail.com>

Overview of P1020RDB-PD device:
- DDR3 2GB
- NOR flash 64MB
- NAND flash 128MB
- SPI flash 16MB
- I2C EEPROM 256Kb
- eTSEC1 (RGMII PHY) connected to VSC7385 L2 switch
- eTSEC2 (SGMII PHY)
- eTSEC3 (RGMII PHY)
- SDHC
- 1 USB ports
- TDM ports
- PCIe
Signed-off-by: NHaijun Zhang <Haijun.Zhang@freescale.com>
Signed-off-by: NJerry Huang <Chang-Ming.Huang@freescale.com>
Signed-off-by: NXie Xiaobo-R63061 <X.Xie@freescale.com>
CC: Scott Wood <scottwood@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

The p1020rdb-pd has the similar feature as the p1020rdb.
Therefore, p1020rdb-pd use the same platform file as the p1/p2 rdb board.
Overview of P1020RDB-PD platform:
- DDR3 2GB
- NOR flash 64MB
- NAND flash 128MB
- SPI flash 16MB
- I2C EEPROM 256Kb
	- eTSEC1 (RGMII PHY) connected to VSC7385 L2 switch
	- eTSEC2 (SGMII PHY)
- eTSEC3 (RGMII PHY)
	- SDHC
	- 2 USB ports
	- 4 TDM ports
	- PCIe
Signed-off-by: NHaijun Zhang <Haijun.Zhang@freescale.com>
Signed-off-by: NJerry Huang <Chang-Ming.Huang@freescale.com>
CC: Scott Wood <scottwood@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

At console init, when the kernel tries to flush the log buffer
the ePAPR byte-channel based console write fails silently,
losing the buffered messages.
This happens because The ePAPR para-virtualization init isn't
done early enough so that the hcall instruction to be set,
causing the byte-channel write hcall to be a nop.
To fix, change the ePAPR para-virt init to use early device
tree functions and move it in early init.
Signed-off-by: NLaurentiu Tudor <Laurentiu.Tudor@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

The original MPIC MSI bank contains 8 registers, MPIC v4.3 MSI bank
contains 16 registers, and this patch adds NR_MSI_REG_MAX and
NR_MSI_IRQS_MAX to describe the maximum capability of MSI bank.
MPIC v4.3 provides MSIIR1 to index these 16 MSI registers. MSIIR1
uses different bits definition than MSIIR. This patch adds
ibs_shift and srs_shift to indicate the bits definition of the
MSIIR and MSIIR1, so the same code can handle the MSIIR and MSIIR1
simultaneously.
Signed-off-by: NMinghuan Lian <Minghuan.Lian@freescale.com>
[scottwood@freescale.com: reinstated static on all_avail]
Signed-off-by: NScott Wood <scottwood@freescale.com>

For the latest platform T4 and B4, MPIC controller has been updated
to v4.3. This patch adds a new file to describe the latest MPIC.
The MSI blocks number is increased to four, the registers number
of each block is increased to sixteen. MSIIR1 has been added to
access these sixteen MSI registers.
Signed-off-by: NMinghuan Lian <Minghuan.Lian@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

Add compatible "fsl,mpic-msi-v4.3" for MPIC v4.3. MPIC v4.3 contains
MSIIR and MSIIR1. MSIIR supports 8 MSI registers and MSIIR1 supports
16 MSI registers, but uses different IBS and SRS shift. When using
MSIR1, the interrupt number is not consecutive. It is hard to use
'msi-available-ranges' to describe the ranges of the available
interrupt, so MPIC v4.3 does not support this property.
Signed-off-by: NMinghuan Lian <Minghuan.Lian@freescale.com>
[scottwood@freescale.com: minor grammar fixes]
Signed-off-by: NScott Wood <scottwood@freescale.com>

mpic_get_primary_version() is not defined when not using MPIC.
The compile error log like:

arch/powerpc/sysdev/built-in.o: In function `fsl_of_msi_probe':
fsl_msi.c:(.text+0x150c): undefined reference to `fsl_mpic_primary_get_version'
Signed-off-by: NJia Hongtao <hongtao.jia@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

e6500 core performance monitors has the following features:
- 6 performance monitor counters
- 512 events supported
- no threshold events

e6500 PMU has more specific events (Data L1 cache misses, Instruction L1
cache misses, etc ) than e500 PMU (which only had Data L1 cache reloads,
etc). Where available, the more specific events have been used which will
produce slightly different results than e500 PMU equivalents.
Signed-off-by: NPriyanka Jain <Priyanka.Jain@freescale.com>
Signed-off-by: NLijun Pan <Lijun.Pan@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

There are 6 counters in e6500 core instead of 4 in e500 core.
Signed-off-by: NLijun Pan <Lijun.Pan@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

This change is required after the e6500 perf support has been added.
There are 6 counters in e6500 core instead of 4 in e500 core and
the MAX_HWEVENTS counter should be changed accordingly from 4 to 6.
Added also runtime check for counters overflow.
Signed-off-by: NCatalin Udma <catalin.udma@freescale.com>
Signed-off-by: NLijun Pan <Lijun.Pan@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

Signed-off-by: NLijun Pan <Lijun.Pan@freescale.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

This file is a common include for B4860 and B4420 but is not a valid DTS itself:
	  DTC     arch/powerpc/boot/b4qds.dtb
	Error: arch/powerpc/boot/dts/b4qds.dts:35.1-2 syntax error
	FATAL ERROR: Unable to parse input tree
	make[1]: *** [arch/powerpc/boot/b4qds.dtb] Error 1
	make: *** [b4qds.dtb] Error 2

I spotted in build tests of device-tree.git, announcement
https://lkml.org/lkml/2013/4/24/209, which builds *.dts. Probably no one would
do this this in real life on linux.git but it still seems worth fixing.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Cc: Shaveta Leekha <shaveta@freescale.com>
Cc: Minghuan Lian <Minghuan.Lian@freescale.com>
Cc: Andy Fleming <afleming@freescale.com>
Cc: Poonam Aggrwal <poonam.aggrwal@freescale.com>
Cc: Ramneek Mehresh <ramneek.mehresh@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NScott Wood <scottwood@freescale.com>

Merge tag 'trace-fixes-3.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Oleg Nesterov has been working hard in closing all the holes that can
  lead to race conditions between deleting an event and accessing an
  event debugfs file.  This included a fix to the debugfs system (acked
  by Greg Kroah-Hartman).  We think that all the holes have been patched
  and hopefully we don't find more.  I haven't marked all of them for
  stable because I need to examine them more to figure out how far back
  some of the changes need to go.

  Along the way, some other fixes have been made.  Alexander Z Lam fixed
  some logic where the wrong buffer was being modifed.

  Andrew Vagin found a possible corruption for machines that actually
  allocate cpumask, as a reference to one was being zeroed out by
  mistake.

  Dhaval Giani found a bad prototype when tracing is not configured.

  And I not only had some changes to help Oleg, but also finally fixed a
  long standing bug that Dave Jones and others have been hitting, where
  a module unload and reload can cause the function tracing accounting
  to get screwed up"

* tag 'trace-fixes-3.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix reset of time stamps during trace_clock changes
  tracing: Make TRACE_ITER_STOP_ON_FREE stop the correct buffer
  tracing: Fix trace_dump_stack() proto when CONFIG_TRACING is not set
  tracing: Fix fields of struct trace_iterator that are zeroed by mistake
  tracing/uprobes: Fail to unregister if probe event files are in use
  tracing/kprobes: Fail to unregister if probe event files are in use
  tracing: Add comment to describe special break case in probe_remove_event_call()
  tracing: trace_remove_event_call() should fail if call/file is in use
  debugfs: debugfs_remove_recursive() must not rely on list_empty(d_subdirs)
  ftrace: Check module functions being traced on reload
  ftrace: Consolidate some duplicate code for updating ftrace ops
  tracing: Change remove_event_file_dir() to clear "d_subdirs"->i_private
  tracing: Introduce remove_event_file_dir()
  tracing: Change f_start() to take event_mutex and verify i_private != NULL
  tracing: Change event_filter_read/write to verify i_private != NULL
  tracing: Change event_enable/disable_read() to verify i_private != NULL
  tracing: Turn event/id->i_private into call->event.type

Pull vfs fixes from Al Viro.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vfs: add missing check for __O_TMPFILE in fcntl_init()
  fs: Allow unprivileged linkat(..., AT_EMPTY_PATH) aka flink
  fs: Fix file mode for O_TMPFILE
  reiserfs: fix deadlock in umount

Pull libata fix from Tejun Heo:
 "Just the addition of MODULE_DEVICE_TABLE() for a platform driver"

* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  pata_imx: expose module alias for loading from device-tree

Pull cgroup fix from Tejun Heo:
 "Fix for a minor memory leak bug in the cgroup init failure path"

* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix a leak when percpu_ref_init() fails

Pull two workqueue fixes from Tejun Heo:
 "A lockdep notation update so that nested work_on_cpu() invocations
  don't lead to spurious lockdep warnings and fix for an unbound attr
  bug which made what's shown in sysfs deviate from the actual ones.
  Both patches have pretty limited scope"

* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: copy workqueue_attrs with all fields
  workqueue: allow work_on_cpu() to be called recursively

Pull misc x86 fixes from Peter Anvin.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, amd, microcode: Fix error path in apply_microcode_amd()
  x86, fpu: correct the asm constraints for fxsave, unbreak mxcsr.daz
  x86, efi: correct call to free_pages
  x86/iommu/vt-d: Expand interrupt remapping quirk to cover x58 chipset

Some of my configs I test with have CONFIG_A11Y_BRAILLE_CONSOLE set.
When I started testing against v3.11-rc4 my console went bonkers.  Using
ktest to bisect the issue, it came down to:

commit bbeddf52 "printk: move braille console support into separate
braille.[ch] files"

Looking into the patch I found the problem.  It's with the return of
braille_register_console().  As anything other than NULL is considered a
failure.

But for those of us that have CONFIG_A11Y_BRAILLE_CONSOLE set but do not
define a "brl" or "brl=" on the command line, we still may want a
console that those with sight can still use.

Return NULL (success) if "brl" or "brl=" is not on the console line.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
Acked-by: NJoe Perches <joe@perches.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit fab840fc.

This commit even has the test-case to prove that the tracee
can be killed by SIGTRAP if the debugger does not remove the
breakpoints before PTRACE_DETACH.

However, this is exactly what wineserver deliberately does,
set_thread_context() calls PTRACE_ATTACH + PTRACE_DETACH just
for PTRACE_POKEUSER(DR*) in between.

So we should revert this fix and document that PTRACE_DETACH
should keep the breakpoints.
Reported-by: NFelipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull MIPS fixes from Ralf Baechle:
 "Two platform-specific fixes plus a fix for oprofile which was calling
  smp_processor_id() in preemptible code"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: BMIPS: fix hardware interrupt routing for boot CPU != 0
  MIPS: oprofile: Fix BUG due to smp_processor_id() in preemptible code.
  MIPS: PNX833x: PNX8335_PCI_ETHERNET_INT depends on CONFIG_SOC_PNX8335

Pull s390 fixes from Martin Schwidefsky:
 "Enable LZ4 compression for the kernel image, add the machine id for
  the new zBC12 model, fix an issue with hanging dasd devices, correct a
  Kconfig dependency, fix a compile error in the perf module with
  CONFIG_KVM=n and fix the find_next_bit_left primitive for the PCI base
  layer"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/dasd: fix hanging devices after path events
  s390/perf: fix compile error (undefined reference sie_exit)
  s390/bitops: fix find_next_bit_left
  s390: add support for IBM zBC12 machine
  s390/Kconfig: select 'TTY' when 'S390_GUEST' is enabled
  s390: add support for LZ4-compressed kernel

unshare_userns(new_cred) does *new_cred = prepare_creds() before
create_user_ns() which can fail. However, the caller expects that
it doesn't need to take care of new_cred if unshare_userns() fails.

We could change the single caller, sys_unshare(), but I think it
would be more clean to avoid the side effects on failure, so with
this patch unshare_userns() does put_cred() itself and initializes
*new_cred only if create_user_ns() succeeeds.

Cc: stable@vger.kernel.org
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Reviewed-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As comment in include/uapi/asm-generic/fcntl.h described, when
introducing new O_* bits, we need to check its uniqueness in
fcntl_init().  But __O_TMPFILE bit is missing.  So fix it.
Signed-off-by: NZheng Liu <wenqing.lz@taobao.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Every now and then someone proposes a new flink syscall, and this spawns
a long discussion of whether it would be a security problem.  I think
that this is missing the point: flink is *already* allowed without
privilege as long as /proc is mounted -- it's called AT_SYMLINK_FOLLOW.

Now that O_TMPFILE is here, the ability to create a file with O_TMPFILE,
write it, and link it in is very convenient.  The only problem is that
it requires that /proc be mounted so that you can do:

linkat(AT_FDCWD, "/proc/self/fd/<tmpfd>", dfd, path, AT_SYMLINK_NOFOLLOW)

This sucks -- it's much nicer to do:

linkat(tmpfd, "", dfd, path, AT_EMPTY_PATH)

Let's allow it.

If this turns out to be excessively scary, it we could instead require
that the inode in question be I_LINKABLE, but this seems pointless given
the /proc situation
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

O_TMPFILE, like O_CREAT, should respect the requested mode and should
create regular files.

This fixes two bugs: O_TMPFILE required privilege (because the mode
ended up as 000) and it produced bogus inodes with no type.
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Since remove_proc_entry() started to wait for IO in progress (i.e.
since 2007 or so), the locking in fs/reiserfs/proc.c became wrong;
if procfs read happens between the moment when umount() locks the
victim superblock and removal of /proc/fs/reiserfs/<device>/*,
we'll get a deadlock - read will wait for s_umount (in sget(),
called by r_start()), while umount will wait in remove_proc_entry()
for that read to finish, holding s_umount all along.

Fortunately, the same change allows a much simpler race avoidance -
all we need to do is remove the procfs entries in the very beginning
of reiserfs ->kill_sb(); that'll guarantee that pointer to superblock
will remain valid for the duration for procfs IO, so we don't need
sget() to keep the sucker alive.  As the matter of fact, we can
get rid of the home-grown iterator completely, and use single_open()
instead.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The hardware interrupt routing for boot CPU != 0 is wrong because it
will route all the hardware interrupts to TP0 which is not the one we
booted from. Fix this by properly checking which boot CPU we are booting
from and updating the right interrupt mask for the boot CPU. This fixes
booting on BCM3368 with bmips_smp_emabled = 0.
Signed-off-by: NFlorian Fainelli <florian@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: blogic@openwrt.org
Cc: jogo@openwrt.org
Cc: cernekee@gmail.com
Patchwork: https://patchwork.linux-mips.org/patch/5650/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

current_cpu_type() is not preemption-safe.
If CONFIG_PREEMPT is enabled then mipsxx_reg_setup() can be called from preemptible state.
Added get_cpu()/put_cpu() pair to make it preemption-safe.

This was found while testing oprofile with CONFIG_DEBUG_PREEMPT enable.

/usr/zntestsuite # opcontrol --init
/usr/zntestsuite # opcontrol --setup --event=L2_CACHE_ACCESSES:500 --event=L2_CACHE_MISSES:500 --no-vmlinux
/usr/zntestsuite # opcontrol --start
Using 2.6+ OProfile kernel interface.
BUG: using smp_processor_id() in preemptible [00000000] code: oprofiled/1362
caller is mipsxx_reg_setup+0x11c/0x164
CPU: 0 PID: 1362 Comm: oprofiled Not tainted 3.10.4 #18
Stack : 00000006 70757465 00000000 00000000 00000000 00000000 80b173f6 00000037
          80b10000 00000000 80b21614 88f5a220 00000000 00000000 00000000 00000000
          00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
          00000000 00000000 00000000 89c49c00 89c49c2c 80721254 807b7927 8012c1d0
          80b10000 80721254 00000000 00000552 88f5a220 80b1335c 807b78e6 89c49ba8
          ...
Call Trace:
[<801099a4>] show_stack+0x64/0x7c
[<80665520>] dump_stack+0x20/0x2c
[<803a2250>] debug_smp_processor_id+0xe0/0xf0
[<8052df24>] mipsxx_reg_setup+0x11c/0x164
[<8052cd70>] op_mips_setup+0x24/0x4c
[<80529cfc>] oprofile_setup+0x5c/0x12c
[<8052b9f8>] event_buffer_open+0x78/0xf8
[<801c3150>] do_dentry_open.isra.15+0x2b8/0x3b0
[<801c3270>] finish_open+0x28/0x4c
[<801d49b8>] do_last.isra.41+0x2cc/0xd00
[<801d54a0>] path_openat+0xb4/0x4c4
[<801d5c44>] do_filp_open+0x3c/0xac
[<801c4744>] do_sys_open+0x110/0x1f4
[<8010f47c>] stack_done+0x20/0x44

Bug reported and original patch by Jerin Jacob <jerinjacobk@gmail.com>.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Acked-by: NJerin Jacob <jerinjacobk@gmail.com>

The PNX8335_PCI_ETHERNET_INT macro is defined in
arch/mips/include/asm/mach-pnx833x/irq-mapping.h
only if CONFIG_SOC_PNX8335 is selected.

Fixes the following randconfig problem:
arch/mips/pnx833x/common/platform.c:210:12:
error: 'PNX8335_PIC_ETHERNET_INT' undeclared here
(not in a function)
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Acked-by: NSteven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5585/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Pull dmaengine fixes from Vinod Koul:
 "Two fixes for slave dmaengine.  The first fixes cyclic dma transfers
  for pl330 and the second one makes us return the correct error code on
  probe"

* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
  dma: pl330: Fix cyclic transfers
  pch_dma: fix error return code in pch_dma_probe()

Pull drm fix from Dave Airlie:
 "Just a quick fix that a few people have reported, be nice to have in
  asap"

The drm tree seems to be very confused about 64-bit divides.  Here it
uses a slow 64-by-64 bit divide to divide by a small constant.  Oh well.
Doesn't look performance-critical, just stupid.

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/radeon: fix 64 bit divide in SI spm code