This adds some code based on code from the Broadcom GPL tar to fix the
reboot problems on BCM4705/BCM4785. I tried rebooting my device for ~10
times and have never seen a problem. This reverts the changes in the
previous commit and adds the real fix as suggested by Rafał.
Setting bit 22 in Reg 22, sel 4 puts the BIU (Bus Interface Unit) into
async mode.
The previous commit was 316cad5c1d [MIPS:
BCM47XX: make reboot more relaiable]
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Cc: jogo@openwrt.org
Cc: zajec5@gmail.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7545/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add common declaration to get rid of following sparse warning: "symbol
'plat_irq_dispatch' was not declared. Should it be static?"
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: Linux MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/7539/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Remove unused argument to make the plat_irq_dispatch() function
declaration similar to the realization of other platforms.
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: Linux MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/7538/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Valleyview and Cherryview have the same behavior on display audio. So this patch
defines is_valleyview_plus() to include codecs for both Valleyview and its successor
Cherryview, and apply Valleyview fix-ups to Cherryview.
Signed-off-by: Libin Yang <libin.yang@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Both Haswell and Broadwell need set depop_delay to 0. So apply this
setting to haswell plus.
Signed-off-by: Libin Yang <libin.yang@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Most places which allocate an r10_bio zero the ->state, some don't.
As the r10_bio comes from a mempool, and the allocation function uses
kzalloc it is often zero anyway. But sometimes it isn't and it is
best to be safe.
I only noticed this because of the bug fixed by an earlier patch
where the r10_bios allocated for a reshape were left around to
be used by a subsequent resync. In that case the R10BIO_IsReshape
flag caused problems.
Signed-off-by: NeilBrown <neilb@suse.de>
When a raid10 commences a resync/recovery/reshape it allocates
some buffer space.
When a resync/recovery completes the buffer space is freed. But not
when the reshape completes.
This can result in a small memory leak.
There is a subtle side-effect of this bug. When a RAID10 is reshaped
to a larger array (more devices), the reshape is immediately followed
by a "resync" of the new space. This "resync" will use the buffer
space which was allocated for "reshape". This can cause problems
including a "BUG" in the SCSI layer. So this is suitable for -stable.
Cc: stable@vger.kernel.org (v3.5+)
Fixes: 3ea7daa5d7
Signed-off-by: NeilBrown <neilb@suse.de>
raid10 reshape clears unwanted bits from a bio->bi_flags using
a method which, while clumsy, worked until 3.10 when BIO_OWNS_VEC
was added.
Since then it clears that bit but shouldn't. This results in a
memory leak.
So change to used the approved method of clearing unwanted bits.
As this causes a memory leak which can consume all of memory
the fix is suitable for -stable.
Fixes: a38352e0ac
Cc: stable@vger.kernel.org (v3.10+)
Reported-by: mdraid.pkoch@dfgh.net (Peter Koch)
Signed-off-by: NeilBrown <neilb@suse.de>
On some HP laptops, the mute led is controlled by codec gpio.
When some machine resume from s3/s4, the codec gpio data will be
cleared to 0 by BIOS:
Before suspend:
IO[3]: enable=1, dir=1, wake=0, sticky=0, data=1, unsol=0
After resume:
IO[3]: enable=1, dir=1, wake=0, sticky=0, data=0, unsol=0
To skip the AFG node to enter D3 can't fix this problem.
A workaround is to restore the gpio data when the system resume
back from s3/s4. It is safe even on the machines without this
problem.
BugLink: https://bugs.launchpad.net/bugs/1358116
Tested-by: Franz Hsieh <franz.hsieh@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Crucial M550 may cause data corruption on queued trims and is
blacklisted. The pattern used for it fails to match 1TB one as the
capacity section will be four chars instead of three. Widen the
pattern.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Charles Reiss <woggling@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=81071
Cc: stable@vger.kernel.org
It isn't necessary for command streams generated by the kernel (at least
not while we aren't storing ring or indirect buffers in VRAM).
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Instead of hard coding the value properly document
that this is an userspace interface.
No intended functional change.
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
In RT kernel, I ran into the following calltrace, so PMU interrupts cannot
be threaded
in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0
INFO: lockdep is turned off.
Call Trace:
[<ffffffff8088595c>] dump_stack+0x1c/0x50
[<ffffffff801a958c>] __might_sleep+0x13c/0x148
[<ffffffff80891c54>] rt_spin_lock+0x3c/0xb0
[<ffffffff801ad29c>] __wake_up+0x3c/0x80
[<ffffffff80243ba4>] perf_event_wakeup+0x8c/0xf8
[<ffffffff80243c50>] perf_pending_event+0x40/0x78
[<ffffffff8023d88c>] irq_work_run+0x74/0xc0
[<ffffffff80152640>] mipsxx_pmu_handle_shared_irq+0x110/0x228
[<ffffffff8015276c>] mipsxx_pmu_handle_irq+0x14/0x30
[<ffffffff801ffda4>] handle_irq_event_percpu+0xbc/0x470
[<ffffffff80204478>] handle_percpu_irq+0x98/0xc8
[<ffffffff801ff284>] generic_handle_irq+0x4c/0x68
[<ffffffff8089748c>] do_IRQ+0x2c/0x48
[<ffffffff80105864>] plat_irq_dispatch+0x64/0xd0
[ralf@linux-mips.org: I don't see why based on this register dump the
handler should be marked IRQF_NO_THREAD - but the handler is manipulating
per-CPU resources so we don't want it to be rescheduled to another CPU.]
Signed-off-by: Yang Wei <Wei.Yang@windriver.com>
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: mingo@redhat.com
Cc: acme@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7506/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 9183df25fe ("shm: add memfd_create() syscall") added a new
system call (memfd_create) but didn't update the asm-generic unistd
header.
This patch adds the new system call to the asm-generic version of
unistd.h so that it can be used by architectures such as arm64.
Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arch/arm/ just grew support for the new memfd_create and getrandom
syscalls, so add them to our compat layer too.
Signed-off-by: Will Deacon <will.deacon@arm.com>
This removes an unfortunately placed semi-colon resulting in all instruction
caches being classified as AIVIVT.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Atm we may retrain the DP link even if the CRTC is inactive through
HPD work->intel_dp_check_link_status(). This in turn can lock up the PHY
(at least on BYT), since the DP port is disabled.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=81948
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org (3.16+)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Atm we may leave eDP VDD enabled during system suspend after the CRTCs
are disabled through an HPD->DPCD read event. So disable VDD during
suspend at a point when no HPDs can occur.
Note that runtime suspend doesn't have the same problem, since there the
RPM ref held by VDD provides already the needed serialization.
v2:
- add note to commit message about the runtime suspend path (Ville)
- use edp_panel_vdd_off_sync(), so we can keep the WARN in
edp_panel_vdd_off() (Ville)
v3:
- rebased on -fixes (for_each_intel_encoder()->list_for_each_entry())
(Imre)
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> (v2)
Cc: stable@vger.kernel.org (3.16+)
[Jani: fix sparse warning reported by Fengguang Wu]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Make sure these work handlers don't run after we system suspend or
unload the driver. Note that we don't cancel the handlers during runtime
suspend. That could lead to a lockup, since we take a runtime PM ref
from the handlers themselves. Fortunaltely canceling there is not needed
since the RPM ref itself provides for the needed serialization.
v2:
- fix the order of canceling dig_port_work wrt. hotplug_work (Ville)
- zero out {long,short}_hpd_port_mask and hpd_event_bits for speed
(Ville)
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org (3.16+)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Atm, the HPD IRQ reenable timer can get rearmed right after it's
canceled. Also to access the HPD IRQ mask registers we need to wake up
the HW.
Solve both issues by converting the reenable timer to a delayed work and
grabbing a runtime PM reference in the work. By this we can also forgo
canceling the timer during runtime suspend, since the only important
thing there is that the HW is awake when we write the registers and
that's ensured by the RPM ref. So do the cancelation only during driver
unload time; this is also a requirement for an upcoming patch where we
want to cancel all HPD related works only during system suspend and
driver unload time, but not during runtime suspend.
Note that there is still a race between the HPD IRQ reenable work and
drm_irq_uninstall() during driver unload, where the work can reenable
the HPD IRQs disabled by drm_irq_uninstall(). This isn't a problem since
the HPD IRQs will still be effectively masked by the first level
interrupt mask.
v2-3:
- unchanged
v4:
- use proper API for changing the expiration time for an already pending
delayed work (Jani)
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> (v2)
Cc: stable@vger.kernel.org (3.16+)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Ville noticed that we can call ibx_digital_port_connected() which accesses
the HW without holding any power well/runtime pm reference. Fix this by
holding a display port power domain reference around the whole hpd_pulse
handler.
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Cc: stable@vger.kernel.org (3.16+)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
radeon fixes for 3.17, kind of all over the place (dpm, GPUVM, etc.)
* 'drm-fixes-3.17' of git://people.freedesktop.org/~agd5f/linux:
drm/radeon: Remove duplicate include from Makefile
drm/radeon/dpm: select the appropriate vce power state for KV/KB/ML
drm/radeon: Add ability to get and change dpm state when radeon PX card is turned off
drm/radeon: Add missing lines to ci_set_thermal_temperature_range
drm/radeon: Always flush VM again on < CIK
drm/radeon: add a check for allocation failure (v2)
drm/radeon: use pfp for all vm_flush related updates
drm/radeon: add bapm module parameter
When multiple devices are detached in __detach_device, they
are also removed from the domains dev_list. This makes it
unsafe to use list_for_each_entry_safe, as the next pointer
might also not be in the list anymore after __detach_device
returns. So just repeatedly remove the first element of the
list until it is empty.
Cc: stable@vger.kernel.org
Tested-by: Marti Raudsepp <marti@juffo.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
When the BUS_NOTIFY_DEL_DEVICE event is received the device
might still be attached to a driver. In this case the domain
can't be released as the mappings might still be in use.
Defer the domain removal in this case until we receivce the
BUS_NOTIFY_UNBOUND_DRIVER event.
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: stable@vger.kernel.org # v3.15, v3.16
Signed-off-by: Joerg Roedel <jroedel@suse.de>
If pwm_get() finds a look-up entry with a perfect match (both dev_id and
con_id match), the loop is aborted, and "p" still points to the correct
struct pwm_lookup.
If only an entry with a matching dev_id or con_id is found, the loop
terminates after traversing the whole list, and "p" now points to
arbitrary memory, not part of the pwm_lookup list.
Then pwm_set_period() and pwm_set_polarity() will set random values for
period resp. polarity.
To fix this, save period and polarity when finding a new best match,
just like is done for chip (for the provider) and index.
This fixes the LCD backlight on r8a7740/armadillo-legacy, which was fed
period 0 and polarity -1068821144 instead of 33333 resp. 1.
Fixes: 3796ce1d4d ("pwm: add period and polarity to struct pwm_lookup")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: stable@vger.kernel.org
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Make sure the cursor gets fully clipped when enabling it on a disabled
crtc via setplane. This will prevent the lower level code from
attempting to enable the cursor in hardware.
Cc: Paulo Zanoni <przanoni@gmail.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
During suspend we turn off the crtcs, but leave the staged config in
place so that we can restore the display(s) to their previous state on
resume.
During resume when we attempt to apply the force pipe A quirk we use the
load detect mechanism. That doesn't check whether there was an already
staged configuration for the crtc since that's not even possible during
normal runtime load detection. But during resume it is possible, and if
we just blindly go and overwrite the staged crtc configuration for the
load detection we can no longer restore the display to the correct
state.
Even worse, we don't even clear all the staged connector->encoder->crtc
links so we may end up using a cloned setup for the load detection, and
after we're done we just clear the links related to the VGA output
leaving the links for the other outputs in place. This will eventually
result in calling intel_set_mode() with mode==NULL but with valid
connector->encoder->crtc links which will result in dereferencing the
NULL mode since the code thinks it will have to a modeset.
To avoid these problems don't use any crtc with new_enabled==true for
load detection.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org (for 3.16)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
intel_enable_pipe_a() gets called with all the modeset locks already
held (by drm_modeset_lock_all()), so trying to grab the same
locks using another drm_modeset_acquire_ctx is going to fail miserably.
Move most of the drm_modeset_acquire_ctx handling (init/drop/fini)
out from intel_{get,release}_load_detect_pipe() into the callers
(intel_{crt,tv}_detect()). Only the actual locking and backoff
handling is left in intel_get_load_detect_pipe(). And in
intel_enable_pipe_a() we just share the mode_config.acquire_ctx from
drm_modeset_lock_all() which is already holding all the relevant locks.
It's perfectly legal to lock the same ww_mutex multiple times using the
same ww_acquire_ctx. drm_modeset_lock() will convert the returned
-EALREADY into 0, so the caller doesn't need to do antyhing special.
Fixes a hang on resume on my 830.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
On i.MX6Q, gpu2d_axi and gpu3d_axi are either from AXI or
AHB clock, but on i.MX6DL, gpu2d_axi and gpu3d_axi are
from mmdc_ch0_axi_podf, and they can NOT be gated by mmdc_ch0_axi
's clock gate, the mux option register field(CCM_CBCMR)
is marked as "Reserved" now on i.MX6DL RM, so correct these
two clks setting.
Signed-off-by: Anson Huang <b20788@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
During recovery of a double-degraded RAID6 it is possible for
some blocks not to be recovered properly, leading to corruption.
If a write happens to one block in a stripe that would be written to a
missing device, and at the same time that stripe is recovering data
to the other missing device, then that recovered data may not be written.
This patch skips, in the double-degraded case, an optimisation that is
only safe for single-degraded arrays.
Bug was introduced in 2.6.32 and fix is suitable for any kernel since
then. In an older kernel with separate handle_stripe5() and
handle_stripe6() functions the patch must change handle_stripe6().
Cc: stable@vger.kernel.org (2.6.32+)
Fixes: 6c0069c0ae
Cc: Yuri Tikhonov <yur@emcraft.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Reported-by: "Manibalan P" <pmanibalan@amiindia.co.in>
Tested-by: "Manibalan P" <pmanibalan@amiindia.co.in>
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1090423
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
If a stripe in a raid6 array received a write to each data block while
the array is degraded, and if any of these writes to a missing device
are not page-aligned, then a live-lock happens.
In this case the P and Q blocks need to be read so that the part of
the missing block which is *not* being updated by the write can be
constructed. Due to a logic error, these blocks are not loaded, so
the update cannot proceed and the stripe is 'handled' repeatedly in an
infinite loop.
This bug is unlikely as most writes are page aligned. However as it
can lead to a livelock it is suitable for -stable. It was introduced
in 3.16.
Cc: stable@vger.kernel.org (v3.16)
Fixed: 67f455486d
Signed-off-by: NeilBrown <neilb@suse.de>
Previous version had an extra 'fsl' which made the pins not match
any entry. The console message,
vf610-pinctrl 40048000.iomuxc: no fsl,pins property in node \
/soc/aips-bus@40000000/iomuxc@40048000/vf610-twr/esdhc1grp
is displayed without the fix. The prior version would generally
work as u-boot sets the pins properly for sdhc. This change allows
Linux sdhc use even if u-boot is built without sdhc support.
Signed-off-by: Bill Pringlemeir <bpringlemeir@nbsps.com>
Acked-by: Stefan Agner <stefan@agner.ch>
Fixes: 0517fe6aa8 ("ARM: dts: vf610-twr: Add support for sdhc1")
Cc: <stable@vger.kernel.org>
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Since ARCH_MXC already selects ARCH_HAS_OPP, it's really unnecessary for
SOC_IMX27 and SOC_IMX5 to select it again.
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
After the suspend routine running in OCRAM puts DDR into self-refresh,
it will access IOMUXC block to float DDR IO for power saving. A TLB
missing of IOMUXC base address may happen in this case, and triggers an
access to DDR, and thus hangs the system.
The failure is discovered by running suspend/resume on a Cubox-i board.
Though the issue is not Cubox-i specific, it can be hit the on the board
quite easily with the 3.15 or 3.16 kernel.
Fix the issue with a dummy access to IOMUXC block at the beginning of
suspend routine, so that the address translation can be filled into TLB
before DDR is put into self-refresh.
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Cc: <stable@vger.kernel.org>
Acked-by: Anson Huang <Anson.Huang@freescale.com>
My earlier patch 1fc593feaf ("ARM: imx: build i.MX6 functions
only when needed") fixed a problem with building an i.MX5 kernel,
but now the problem has returned for the case where we allow
ARMv6K SMP builds in multiplatform. With CONFIG_CPU_V7 disabled,
but i.MX3 and SMP enabled, we get this build error:
arch/arm/mach-imx/built-in.o: In function `v7_secondary_startup':
:(.text+0x5124): undefined reference to `v7_invalidate_l1'
This puts the code inside of an "ifdef CONFIG_SOC_IMX6" to hopefully
do the right thing in all configurations.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
fallocate -z (FALLOC_FL_ZERO_RANGE) can map to SMB3
FSCTL_SET_ZERO_DATA SMB3 FSCTL but FALLOC_FL_ZERO_RANGE
when called without the FALLOC_FL_KEEPSIZE flag set could want
the file size changed so we can not support that subcase unless
the file is cached (and thus we know the file size).
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Implement FALLOC_FL_PUNCH_HOLE (which does not change the file size
fortunately so this matches the behavior of the equivalent SMB3
fsctl call) for SMB3 mounts. This allows "fallocate -p" to work.
It requires that the server support setting files as sparse
(which Windows allows).
Signed-off-by: Steve French <smfrench@gmail.com>
When the server (for an SMB2 or SMB3 mount) doesn't support
an ioctl (such as setting the compressed flag
on a file) we were incorrectly returning EIO instead
of EOPNOTSUPP, this is confusing e.g. doing chattr +c to a file
on a non-btrfs Samba partition, now the error returned is more
intuitive to the user. Also fixes error mapping on setting
hardlink to servers which don't support that.
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: David Disseldorp <ddiss@suse.de>
Of_node_put supports NULL as its argument, so the initial test is not
necessary.
Suggested by Uwe Kleine-König.
The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression e;
@@
-if (e)
of_node_put(e);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Zynq GPIO interrupt handling code as two main issues:
1) It does not support IRQF_ONESHOT interrupt since it uses handle_simple_irq()
for the interrupt handler. handle_simple_irq() does not do masking and unmasking
of the IRQ that is required for this chip to be able to support IRQF_ONESHOT
IRQs, causing the CPU to lock up in a interrupt storm if such a interrupt is
requested.
2) Interrupts are acked after the primary interrupt handlers for all asserted
interrupts in a bank have been called. For edge triggered interrupt this is to
late and may cause a interrupt to be missed. For level triggered oneshot
interrupts this is to early and causes the interrupt handler to run twice per
interrupt.
This patch addresses the issue by updating the driver to use the correct IRQ
chip handler functions that are appropriate for this kind of IRQ controller.
The following diagram gives an overview of how the interrupt detection circuit
works, it is not necessarily a accurate depiction of the real hardware though.
INT_POL/INT_ON_ANY
|
| +---+ INT_STATUS
`-| | |
| E |-. |
,---| | \ |\ +----+ | +---+
| +---+ `----| | ,-------|S | ,*--| |
GPIO_IN -* | |- | Q|- | & |-- IRQ_OUT
| +---+ ,-----| | ,-|R | ,o| |
`---| | / |/ | +----+ | +---+
| = |- | | |
,-| | INT_TYPE ACK INT_MASK
| +---+
|
INT_POL
GPIO_IN is the raw signal level connected to the hardware pin. This signal is
routed to a edge detector and to a level detector. The edge detector can be
configured to either detect a rising or falling edge or both edges. The level
detector can detect either a level high or level low event. Depending on the
setting of the INT_TYPE register either the edge or level event will be
propagated to the INT_STATUS register. As long as a interrupt condition is
detected the INT_STATUS register will be set to 1. It can be cleared to 0 if
(and only if) the interrupt condition is no longer detected and software
acknowledges the interrupt by writing a 1 to the address of the INT_STATUS
register. There is also the INT_MASK register which can be used to disable the
propagation of the INT_STATUS signal to the upstream IRQ controller. What is
important to note is that the interrupt detection logic itself can not be
disabled, only the propagation of the INT_STATUS register can be delayed. This
means that for level type interrupts the interrupt must only be acknowledged
after the interrupt source has been cleared otherwise it will stay asserted and
the interrupt handler will be run a second time. For IRQF_ONESHOT interrupts
this means that the IRQ must only be acknowledged after the threaded interrupt
has finished running. If a second interrupt comes in between handling the first
interrupt and acknowledging it the external interrupt will be asserted, which
means trying to acknowledge the first interrupt will not clear the INT_STATUS
register and the interrupt handler will be run a second time when the IRQ is
unmasked, so no interrupts will be lost. The handle_fasteoi_irq() handler in
combination with the IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED flags will
have the desired behavior. For edge triggered interrupts a slightly different
strategy is necessary. For edge triggered interrupts the interrupt condition is
only true when the edge itself is detected, this means this is the only time the
INT_STATUS register is set, acknowledging the interrupt any time after that will
clear the INT_STATUS register until the next interrupt happens. This means in
order to not loose any interrupts the interrupt needs to be acknowledged before
running the interrupt handler. If a second interrupt occurs after the first
interrupt handler has finished but before the interrupt is unmasked the
INT_STATUS register will be re-asserted and the interrupt handler runs a second
time once the interrupt is unmasked. This means with this flow handling strategy
no interrupts are lost for edge triggered interrupts. The handle_level_irq()
handler will have the desired behavior. (Note: The handle_edge_irq() only needs
to be used for edge triggered interrupts where the controller stops detecting
the interrupt event when the interrupt is masked, for this controller the
detection logic still works, while only the propagation is delayed when the
interrupt is masked.)
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Correct typo in the name of the type given to sizeof. Because it is the
size of a pointer that is wanted, the typo has no impact on compilation or
execution.
This problem was found using Coccinelle (http://coccinelle.lip6.fr/). The
semantic patch used can be found in message 0 of this patch series.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
