linux-toradex.git/drivers/macintosh, branch v4.11

powerpc/pmac: Fix crash in dma-mapping.h with NULL dma_ops

2017-03-10T03:17:23+00:00

Commit 5657933dbb6e ("treewide: Move dma_ops from struct dev_archdata
into struct device") introduced a crash for macio devices, an example
backtrace being:

  kernel BUG at ./include/linux/dma-mapping.h:465!
  Oops: Exception in kernel mode, sig: 5 [#1]
  ...
  NIP [c031ddb0] dmam_alloc_coherent+0x74/0x140
  LR [c031de70] dmam_alloc_coherent+0x134/0x140
  Call Trace:
   dmam_alloc_coherent+0x134/0x140 (unreliable)
   pata_macio_port_start+0x3c/0x8c
   ata_host_start.part.5+0xfc/0x208
   ata_host_activate+0x128/0x154
   pata_macio_common_init+0x2f0/0x538
   pata_macio_attach+0xd8/0x180
   macio_device_probe+0x5c/0xec
   driver_probe_device+0x21c/0x314
   __driver_attach+0xcc/0xd0
   bus_for_each_dev+0x68/0xb4
   bus_add_driver+0x1dc/0x244
   driver_register+0x88/0x130
   pata_macio_init+0x5c/0x88
   do_one_initcall+0x40/0x170
   kernel_init_freeable+0x134/0x1d0
   kernel_init+0x18/0x110
   ret_from_kernel_thread+0x5c/0x64

This was caused by the device having NULL dma_ops, triggering the
BUG_ON(). Previously the device inherited its dma_ops via the assignment
to dev->ofdev.dev.archdata. However after commit 5657933dbb6e the
dma_ops are moved into dev->ofdev.dev, and so they need to be explicitly
copied.

Fixes: 5657933dbb6e ("treewide: Move dma_ops from struct dev_archdata into struct device")
Signed-off-by: Larry Finger 
Suggested-by: Benjamin Herrenschmidt 
[mpe: Rewrite change log, add backtrace]
Signed-off-by: Michael Ellerman

sched/headers: Prepare to move signal wakeup & sigpending methods from into

2017-03-02T07:42:32+00:00

Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

Merge tag 'driver-core-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2017-02-22T19:44:32+00:00

Pull driver core updates from Greg KH:
 "Here is the "small" driver core patches for 4.11-rc1.

  Not much here, some firmware documentation and self-test updates, a
  debugfs code formatting issue, and a new feature for call_usermodehelper
  to make it more robust on systems that want to lock it down in a more
  secure way.

  All of these have been linux-next for a while now with no reported
  issues"

* tag 'driver-core-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kernfs: handle null pointers while printing node name and path
  Introduce STATIC_USERMODEHELPER to mediate call_usermodehelper()
  Make static usermode helper binaries constant
  kmod: make usermodehelper path a const string
  firmware: revamp firmware documentation
  selftests: firmware: send expected errors to /dev/null
  selftests: firmware: only modprobe if driver is missing
  platform: Print the resource range if device failed to claim
  kref: prefer atomic_inc_not_zero to atomic_add_unless
  debugfs: improve formatting of debugfs_real_fops()

Merge tag 'powerpc-4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2017-02-22T18:30:38+00:00

Pull powerpc updates from Michael Ellerman:
 "Highlights include:

   - Support for direct mapped LPC on POWER9, giving Linux direct access
     to devices that may be on there such as a UART.

   - Memory hotplug support for the Power9 Radix MMU.

   - Add new AUX vectors describing the processor's cache geometry, to
     be used by glibc.

   - The ability for a guest to ask the hypervisor to resize the guest's
     hash table, and in addition support for doing so automatically when
     memory is hotplugged into/out-of the guest. This allows the hash
     table to be sized based on the current memory usage of the guest,
     rather than the maximum possible memory usage.

   - Implementation of optprobes (kprobe optimisation) for powerpc.

  In addition there's the topic branch shared with the KVM tree, which
  includes support for guests to use the Radix MMU on Power9.

  Thanks to:
    Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T, Anton
    Blanchard, Benjamin Herrenschmidt, Chris Packham, Daniel Axtens,
    Daniel Borkmann, David Gibson, Finn Thain, Gautham R. Shenoy, Gavin
    Shan, Greg Kurz, Joel Stanley, John Allen, Madhavan Srinivasan,
    Mahesh Salgaonkar, Markus Elfring, Michael Neuling, Nathan Fontenot,
    Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Ravi Bangoria, Reza
    Arbab, Shailendra Singh, Vaibhav Jain, Wei Yongjun"

* tag 'powerpc-4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (129 commits)
  powerpc/mm/radix: Skip ptesync in pte update helpers
  powerpc/mm/radix: Use ptep_get_and_clear_full when clearing pte for full mm
  powerpc/mm/radix: Update pte update sequence for pte clear case
  powerpc/mm: Update PROTFAULT handling in the page fault path
  powerpc/xmon: Fix data-breakpoint
  powerpc/mm: Fix build break with BOOK3S_64=n and MEMORY_HOTPLUG=y
  powerpc/mm: Fix build break when CMA=n && SPAPR_TCE_IOMMU=y
  powerpc/mm: Fix build break with RADIX=y & HUGETLBFS=n
  powerpc/pseries: Fix typo in parameter description
  powerpc/kprobes: Remove kprobe_exceptions_notify()
  kprobes: Introduce weak variant of kprobe_exceptions_notify()
  powerpc/ftrace: Fix confusing help text for DISABLE_MPROFILE_KERNEL
  powerpc/powernv: Fix opal_exit tracepoint opcode
  powerpc: Add a prototype for mcount() so it can be versioned
  powerpc: Drop GPL from of_node_to_nid() export to match other arches
  powerpc/kprobes: Optimize kprobe in kretprobe_trampoline()
  powerpc/kprobes: Implement Optprobes
  powerpc/kprobes: Fixes for kprobe_lookup_name() on BE
  powerpc: Add helper to check if offset is within relative branch range
  powerpc/bpf: Introduce __PPC_SH64()
  ...

m68k/mac: Replace via-maciisi driver with via-cuda driver

2017-02-07T05:56:25+00:00

Change the device probe test in the via-cuda.c driver so it will load on
Egret-based machines too. Remove the now redundant via-maciisi.c driver.

Tested-by: Stan Johnson 
Signed-off-by: Finn Thain 
Acked-by: Geert Uytterhoeven 
Signed-off-by: Michael Ellerman

via-cuda: Add support for Egret system controller

2017-02-07T05:56:24+00:00

The Egret system controller was the predecessor to the Cuda and the
differences are minor.

On Cuda, byte acknowledgement requires one transition of the TACK
signal; on Egret two are needed. On Cuda, TIP is active low; on Egret
it is active high. And Cuda raises certain interrupts that Egret omits.

Accomodating these differences complicates the Cuda driver slightly
but avoids a lot of duplication (see next patch).

Tested-by: Stan Johnson 
Signed-off-by: Finn Thain 
Signed-off-by: Michael Ellerman

via-cuda: Initialize data_index early and increment consistently

2017-02-07T05:56:23+00:00

Initialize data_index where appropriate to improve readability and
assist debugging. This change doesn't affect driver behaviour.

I prefer to see
	current_req->data[data_index++]
in place of
	current_req->data[0]
or
	current_req->data[1]
inasmuchas it becomes obvious what the data_index variable does.

Moreover, the actual value of data_index when examined at any given moment
tells me something about prior events, which did prove helpful.

Tested-by: Stan Johnson 
Signed-off-by: Finn Thain 
Signed-off-by: Michael Ellerman

via-cuda: Use spinlock_irq_save/restore instead of enable/disable_irq

2017-02-07T05:56:22+00:00

The cuda_start() function uses spinlock_irq_save/restore for mutual
exclusion. Let's have cuda_poll() do the same when polling the VIA
interrupt.

The benefit to disabling local irqs when the interrupt is being polled
is that the interrupt handler now has the same timing properties
regardless of whether it is invoked normally or from cuda_poll().

This driver was written back when local irqs remained enabled during
execution of interrupt handlers and cuda_poll() was probably trying
to achieve the same effect by use of enable/disable_irq.

Tested-by: Stan Johnson 
Signed-off-by: Finn Thain 
Signed-off-by: Michael Ellerman

via-cuda: Avoid TREQ race condition

2017-02-07T05:56:21+00:00

When a read transaction completes, one of several things will happen:
a new transfer is started by the driver, a new transfer request
is raised by the Cuda (i.e. TREQ asserted), or both happen at once.

When both happen at once, there is a race condition between the TREQ test
in the read_done state and the same test in cuda_start(). Moreover, the
former test uses a stale TREQ value.

Theoretically, this can result in the undesirable outcome that the
interrupt handler completes with the state machine 'idle' when it should
instead start the next transaction.

Avoid this race by calling cuda_start() first and then confirming that it
succeeded. If not, test the current TREQ value before entering the
'reading' state.

Tested-by: Stan Johnson 
Signed-off-by: Finn Thain 
Signed-off-by: Michael Ellerman

via-cuda: Fix re-initialization of reply_ptr and reading_reply

2017-02-07T05:56:20+00:00

When reading_reply is set, reply_ptr points into an adb_request struct.
Conversely, when reply_ptr instead points into the global cuda_rbuf,
reading_reply must be false.

Unfortunately, this rule can be violated because re-initialization
of reply_ptr and reading_reply presently depends on the TREQ input.

Fix this by re-initializing reply_ptr and reading_reply as soon as they
are known to be invalid.

Tested-by: Stan Johnson 
Signed-off-by: Finn Thain 
Signed-off-by: Michael Ellerman