TMU hardware devices can support multiple channels, with global
registers and per-channel registers. The sh_tmu driver currently models
the hardware with one Linux device per channel. This model makes it
difficult to handle global registers in a clean way.

Add support for a new model that uses one Linux device per timer with
multiple channels per device. This requires changes to platform data,
add new channel configuration fields.

Support for the legacy model is kept and will be removed after all
platforms switch to the new model.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

All boards use clock event and clock source ratings of 200 for the TMU,
hardcode it in the driver.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Define symbolic macros for all used registers bits.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

This prepares the driver for multi-channel support.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

One kzalloc a day keeps the bugs away.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Use the index as the timer start/stop bit and when printing messages to
identify the channel.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The channel memory base is channel-specific, add it to the channel
structure in preparation for support of multiple channels per device.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The name argument is assigned to const structure fields only, constify
it.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Move the channel setup code from sh_tmu_setup to a new
sh_tmu_setup_channel function and call it from sh_tmu_setup.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Channel data is private as well, rename priv to device to make the
distrinction between the core device and the channels clearer.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Create a new sh_tmu_channel structure to hold the channel-specific
field in preparation for multiple channels per device support.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The driver claims it needs to register an interrupt handler too early
for request_irq(). This might have been true in the past, but the only
meaningful difference between request_irq() and setup_irq() today is an
additional kzalloc() call in request_irq(). As the driver calls
kmalloc() itself we know that the slab allocator is available, we can
thus switch to request_irq().
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Clock sources don't need an IRQ, request the IRQ only for channels used
as clock event devices.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

This helps locating duplicates and inserting new headers.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Do not include the paragraph about writing to the Free Software
Foundation's mailing address from the sample GPL notice. The FSF has
changed addresses in the past, and may do so again. Linux already
includes a copy of the GPL.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The sh_cmt driver gets the CMT functional clock using a connection ID of
"cmt_fck". While all SH SoCs create clock lookup entries with a NULL
device ID and a "cmt_fck" connection ID, the ARM SoCs use the device ID
only with a NULL connection ID. This works on legacy platforms but will
break on ARM with DT boot.

Fix the situation by using a connection ID of "fck" in the non-legacy
platform data case. Clock lookup entries will be renamed to use the
device ID as well as the connection ID as platforms get moved to new
platform data. The legacy code will eventually be dropped, leaving us
with device ID based clock lookup, compatible with DT boot.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

CMT hardware devices can support multiple channels, with global
registers and per-channel registers. The sh_cmt driver currently models
the hardware with one Linux device per channel. This model makes it
difficult to handle global registers in a clean way.

Add support for a new model that uses one Linux device per timer with
multiple channels per device. This requires changes to platform data,
add new channel configuration fields.

Support for the legacy model is kept and will be removed after all
platforms switch to the new model.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

All boards use or should use a clock source rating of 125 for the CMT,
hardcode it in the driver.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

All boards use or should use a clock event rating of 125 for the CMT,
hardcode it in the driver.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The CMT is a global timer not restricted to a single CPU. It has a lower
rating than the TMU or ARM architected timer, but is still useful on
systems where the other timers are stopped during CPU sleep.

When multiple timers are available the timers core selects which timer
to use based on timer ratings.

On SMP systems where timer broadcasting is required, one dummy timer is
instantiated per CPU with a rating of 100. On those systems the CMT
timer has a rating of 80, which makes the dummy timer selected by
default on all CPUs. The CMT is then available, and will be used as a
broadcast timer.

On UP systems no dummy timer is instantiated. The CMT timer has a rating
of 125 on those systems and is used directly as a clock event device for
CPU0 without broadcasting.

The CMT rating shouldn't depend on whether we boot a UP or SMP system.
We can't raise the CMT rating to 125 on SMP systems. This would select
CMT as the clock event device for CPU0 as its rating is higher than the
dummy timer rating, and would leave the system without a broadcast
timer. We could instead lower the rating to 80 on all systems, but that
wouldn't reflect reality as ratings between 1 and 99 are documented as
"unfit for real use".

We should raise the rating above 99 and still have the CMT selected as a
broadcast timer. This can be done by changing the cpumask from
cpumask_of(0) to cpu_possible_mask. In that case the timer selection
logic will prefer the previously probed and already selected dummy timer
for all CPUs based on the fact that already selected per-cpu timers are
preferred over new global timers, regardless of their respective
ratings. This also better reflects reality, as the CMT is not tied to
the boot CPU.

Ideally the timer selection logic should realize that the CMT needs to
be used as a broadcast timer on SMP systems as no other broadcast timer
is available, regardless of the cpumask and rating.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Define symbolic macros for all used registers bits.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Create a new sh_cmt_info structure to hold static information about the
device model and reference that structure from the sh_cmt_device
structure.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

This prepares the driver for multi-channel support.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

One kzalloc a day keeps the bugs away.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Use the index when printing messages to identify the channel.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The channel memory base is channel-specific, add it to the channel
structure in preparation for support of multiple channels per device.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The mapbase variable points to the mapped base address of the channel,
rename it to mapbase_sh. mapbase_str points to the mapped base address
of the CMT device, rename it to mapbase.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The name argument is assigned to const structure fields only, constify
it.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Move the channel setup code from sh_cmt_setup to a new
sh_cmt_setup_channel function and call it from sh_cmt_setup.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Channel data is private as well, rename priv to device to make the
distrinction between the core device and the channels clearer.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Create a new sh_cmt_channel structure to hold the channel-specific
field in preparation for multiple channels per device support.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

The driver claims it needs to register an interrupt handler too early
for request_irq(). This might have been true in the past, but the only
meaningful difference between request_irq() and setup_irq() today is an
additional kzalloc() call in request_irq(). As the driver calls
kmalloc() itself we know that the slab allocator is available, we can
thus switch to request_irq().
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Some versions of gcc even warn about it:

  mm/shmem.c: In function ‘shmem_file_aio_read’:
  mm/shmem.c:1414: warning: ‘error’ may be used uninitialized in this function

If the loop is aborted during the first iteration by one of the two
first break statements, error will be uninitialized.

Introduced by commit 6e58e79d ("introduce copy_page_to_iter, kill
loop over iovec in generic_file_aio_read()").
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

On 32 bit, size_t is "unsigned int", not "unsigned long", causing the
following warning when comparing with PAGE_SIZE, which is always "unsigned
long":

  fs/cifs/file.c: In function ‘cifs_readdata_to_iov’:
  fs/cifs/file.c:2757: warning: comparison of distinct pointer types lacks a cast

Introduced by commit 7f25bba8 ("cifs_iovec_read: keep iov_iter
between the calls of cifs_readdata_to_iov()"), which changed the
signedness of "remaining" and the code from min_t() to min().
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull slab changes from Pekka Enberg:
 "The biggest change is byte-sized freelist indices which reduces slab
  freelist memory usage:

    https://lkml.org/lkml/2013/12/2/64"

* 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux:
  mm: slab/slub: use page->list consistently instead of page->lru
  mm/slab.c: cleanup outdated comments and unify variables naming
  slab: fix wrongly used macro
  slub: fix high order page allocation problem with __GFP_NOFAIL
  slab: Make allocations with GFP_ZERO slightly more efficient
  slab: make more slab management structure off the slab
  slab: introduce byte sized index for the freelist of a slab
  slab: restrict the number of objects in a slab
  slab: introduce helper functions to get/set free object
  slab: factor out calculate nr objects in cache_estimate

Pull misc kbuild changes from Michal Marek:
 "Here is the non-critical part of kbuild:
   - One bogus coccinelle check removed, one check fixed not to suggest
     the obsolete PTR_RET macro
   - scripts/tags.sh does not index the generated *.mod.c files
   - new objdiff tool to list differences between two versions of an
     object file
   - A fix for scripts/bootgraph.pl"

* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  scripts/coccinelle: Use PTR_ERR_OR_ZERO
  scripts/bootgraph.pl: Add graphic header
  scripts: objdiff: detect object code changes between two commits
  Coccicheck: Remove memcpy to struct assignment test
  scripts/tags.sh: Ignore *.mod.c

This patch fixes I/O errors with the sym53c8xx_2 driver when the disk
returns QUEUE FULL status.

When the controller encounters an error (including QUEUE FULL or BUSY
status), it aborts all not yet submitted requests in the function
sym_dequeue_from_squeue.

This function aborts them with DID_SOFT_ERROR.

If the disk has full tag queue, the request that caused the overflow is
aborted with QUEUE FULL status (and the scsi midlayer properly retries
it until it is accepted by the disk), but the sym53c8xx_2 driver aborts
the following requests with DID_SOFT_ERROR --- for them, the midlayer
does just a few retries and then signals the error up to sd.

The result is that disk returning QUEUE FULL causes request failures.

The error was reproduced on 53c895 with COMPAQ BD03685A24 disk
(rebranded ST336607LC) with command queue 48 or 64 tags.  The disk has
64 tags, but under some access patterns it return QUEUE FULL when there
are less than 64 pending tags.  The SCSI specification allows returning
QUEUE FULL anytime and it is up to the host to retry.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 8f619b54 ("powerpc/ppc64: Do not turn AIL (reloc-on
interrupts) too early") added code to set the AIL bit in the LPCR
without checking whether the kernel is running in hypervisor mode.  The
result is that when the kernel is running as a guest (i.e., under
PowerKVM or PowerVM), the processor takes a privileged instruction
interrupt at that point, causing a panic.  The visible result is that
the kernel hangs after printing "returning from prom_init".

This fixes it by checking for hypervisor mode being available before
setting LPCR.  If we are not in hypervisor mode, we enable relocation-on
interrupts later in pSeries_setup_arch using the H_SET_MODE hcall.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commits 11d4616b ("futex: revert back to the explicit waiter
counting code") and 69cd9eba ("futex: avoid race between requeue and
wake") changed some of the finer details of how we think about futexes.
One was a late fix and the other a consequence of overlooking the whole
requeuing logic.

The first change caused our documentation to be incorrect, and the
second made us aware that we need to explicitly add more details to it.
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>