So we've had a fair few reports of fbcon handover breakage between
efi/vesafb and i915 surface recently, so I dedicated a couple of
days to finding the problem.
Essentially the last thing we saw was the conflicting framebuffer
message and that was all.
So after much tracing with direct netconsole writes (printks
under console_lock not so useful), I think I found the race.
Thread A (driver load) Thread B (timer thread)
unbind_con_driver -> |
bind_con_driver -> |
vc->vc_sw->con_deinit -> |
fbcon_deinit -> |
console_lock() |
| |
| fbcon_flashcursor timer fires
| console_lock() <- blocked for A
|
|
fbcon_del_cursor_timer ->
del_timer_sync
(BOOM)
Of course because all of this is under the console lock,
we never see anything, also since we also just unbound the active
console guess what we never see anything.
Hopefully this fixes the problem for anyone seeing vesafb->kms
driver handoff.
v1.1: add comment suggestion from Alan.
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
Pull fbdev updates from Florian Tobias Schandinat:
- large updates for OMAP
- support for LCD3 overlay manager (omap5)
- omapdss output cleanup
- removal of passive matrix LCD support as there are no drivers for
such panels for DSS or DSS2 and nobody complained (cleanup)
- large updates for SH Mobile
- overlay support
- separating MERAM (cache) from framebuffer driver
- some updates for Exynos and da8xx-fb
- various other small patches
* tag 'fbdev-updates-for-3.6' of git://github.com/schandinat/linux-2.6: (78 commits)
da8xx-fb: fix compile issue due to missing include
fbdev: Make pixel_to_pat() failure mode more friendly
da8xx-fb: do not turn ON LCD backlight unless LCDC is enabled
fbdev: sh_mobile_lcdc: Fix vertical panning step
video: exynos mipi dsi: Fix mipi dsi regulators handling issue
video: da8xx-fb: do clock reset of revision 2 LCDC before enabling
arm: da850: configure LCDC fifo threshold
video: da8xx-fb: configure FIFO threshold to reduce underflow errors
video: da8xx-fb: fix flicker due to 1 frame delay in updated frame
video: da8xx-fb rev2: fix disabling of palette completion interrupt
da8xx-fb: add missing FB_BLANK operations
video: exynos_dp: use usleep_range instead of delay
video: exynos_dp: check the only INTERLANE_ALIGN_DONE bit during Link Training
fb: epson1355fb: Fix section mismatch
video: exynos_dp: fix wrong DPCD address during Link Training
video/smscufx: fix line counting in fb_write
aty128fb: Fix coding style issues
fbdev: sh_mobile_lcdc: Fix pan offset computation in YUV mode
fbdev: sh_mobile_lcdc: Fix overlay registers update during pan operation
fbdev: sh_mobile_lcdc: Support horizontal panning
...
Pull second vfs pile from Al Viro:
"The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the
deadlock reproduced by xfstests 068), symlink and hardlink restriction
patches, plus assorted cleanups and fixes.
Note that another fsfreeze deadlock (emergency thaw one) is *not*
dealt with - the series by Fernando conflicts a lot with Jan's, breaks
userland ABI (FIFREEZE semantics gets changed) and trades the deadlock
for massive vfsmount leak; this is going to be handled next cycle.
There probably will be another pull request, but that stuff won't be
in it."
Fix up trivial conflicts due to unrelated changes next to each other in
drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c}
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
delousing target_core_file a bit
Documentation: Correct s_umount state for freeze_fs/unfreeze_fs
fs: Remove old freezing mechanism
ext2: Implement freezing
btrfs: Convert to new freezing mechanism
nilfs2: Convert to new freezing mechanism
ntfs: Convert to new freezing mechanism
fuse: Convert to new freezing mechanism
gfs2: Convert to new freezing mechanism
ocfs2: Convert to new freezing mechanism
xfs: Convert to new freezing code
ext4: Convert to new freezing mechanism
fs: Protect write paths by sb_start_write - sb_end_write
fs: Skip atime update on frozen filesystem
fs: Add freezing handling to mnt_want_write() / mnt_drop_write()
fs: Improve filesystem freezing handling
switch the protection of percpu_counter list to spinlock
nfsd: Push mnt_want_write() outside of i_mutex
btrfs: Push mnt_want_write() outside of i_mutex
fat: Push mnt_want_write() outside of i_mutex
...
Merge Andrew's first set of patches:
"Non-MM patches:
- lots of misc bits
- tree-wide have_clk() cleanups
- quite a lot of printk tweaks. I draw your attention to "printk:
convert the format for KERN_<LEVEL> to a 2 byte pattern" which
looks a bit scary. But afaict it's solid.
- backlight updates
- lib/ feature work (notably the addition and use of memweight())
- checkpatch updates
- rtc updates
- nilfs updates
- fatfs updates (partial, still waiting for acks)
- kdump, proc, fork, IPC, sysctl, taskstats, pps, etc
- new fault-injection feature work"
* Merge emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits)
drivers/misc/lkdtm.c: fix missing allocation failure check
lib/scatterlist: do not re-write gfp_flags in __sg_alloc_table()
fault-injection: add tool to run command with failslab or fail_page_alloc
fault-injection: add selftests for cpu and memory hotplug
powerpc: pSeries reconfig notifier error injection module
memory: memory notifier error injection module
PM: PM notifier error injection module
cpu: rewrite cpu-notifier-error-inject module
fault-injection: notifier error injection
c/r: fcntl: add F_GETOWNER_UIDS option
resource: make sure requested range is included in the root range
include/linux/aio.h: cpp->C conversions
fs: cachefiles: add support for large files in filesystem caching
pps: return PTR_ERR on error in device_create
taskstats: check nla_reserve() return
sysctl: suppress kmemleak messages
ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION
ipc: compat: use signed size_t types for msgsnd and msgrcv
ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC
ipc: add COMPAT_SHMLBA support
...
Pull PWM subsystem from Thierry Reding:
"The new PWM subsystem aims at collecting all implementations of the
legacy PWM API and to eventually replace it completely.
The subsystem has been in development for over half a year now and
many drivers have already been converted. It has been in linux-next
for a couple of weeks and there have been no major issues so I think
it is ready for inclusion in your tree."
Arnd Bergmann <arnd@arndb.de>:
"Very much Ack on the new subsystem. It uses the interface
declarations as the previously separate pwm drivers, so nothing
changes for now in the drivers using it, although it enables us to
change those more easily in the future if we want to.
This work is also one of the missing pieces that are required to
eventually build ARM kernels for multiple platforms, which is
currently prohibited (amongs other things) by the fact that you cannot
have more than one driver exporting the pwm functions."
Tested-and-acked-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Philip, Avinash <avinashphilip@ti.com> # TI's AM33xx platforms
Acked-By: Alexandre Pereira da Silva <aletes.xgr@gmail.com> # LPC32XX
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sachin Kamat <sachin.kamat@linaro.org>
Fix up trivial conflicts with other cleanups and DT updates.
* 'for-3.6' of git://gitorious.org/linux-pwm/linux-pwm: (36 commits)
pwm: pwm-tiehrpwm: PWM driver support for EHRPWM
pwm: pwm-tiecap: PWM driver support for ECAP APWM
pwm: fix used-uninitialized warning in pwm_get()
pwm: add lpc32xx PWM support
pwm_backlight: pass correct brightness to callback
pwm: Use pr_* functions in pwm-samsung.c file
pwm: Convert pwm-samsung to use devm_* APIs
pwm: Convert pwm-tegra to use devm_clk_get()
pwm: pwm-mxs: Return proper error if pwmchip_remove() fails
pwm: pwm-bfin: Return proper error if pwmchip_remove() fails
pwm: pxa: Propagate pwmchip_remove() error
pwm: Convert pwm-pxa to use devm_* APIs
pwm: Convert pwm-vt8500 to use devm_* APIs
pwm: Convert pwm-imx to use devm_* APIs
pwm: Conflict with legacy PWM API
pwm: pwm-mxs: add pinctrl support
pwm: pwm-mxs: use devm_* managed functions
pwm: pwm-mxs: use global reset function stmp_reset_block
pwm: pwm-mxs: encode soc name in compatible string
pwm: Take over maintainership of the PWM subsystem
...
If we accidentally pass an incorrect bpp value to pixel_to_pat(),
it panics. This is pretty useless, as we generally have the various
console locks held at that point, so nothing will be displayed,
and there is no reason to make this a fatal event.
Let's WARN instead.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
LCD blink is observed during suspend/resume and blank/unblank
operations as backlight is ON during LCDC disable and enable.
So make sure to turn OFF backlight before disabling and turn
it ON after enabling.
Signed-off-by: Manjunathappa, Prakash <prakash.pm@ti.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Commit 15dede882e added support for
horizontal panning but accidentally computes the Y pan step value
incorrectly for NV12/21 and NV16/61 formats. Fix this.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
As in specification software reset should be applied for several
cycles before bringing it out of reset. Without this patch
particularly during suspend and resume clock reset is not guaranteed
to happen.
Signed-off-by: Manjunathappa, Prakash <prakash.pm@ti.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Patch works around the below silicon errata:
During LCDC initialization, there is the potential for a FIFO
underflow condition to occur. A FIFO underflow condition
occurs when the input FIFO is completely empty and the LCDC
raster controller logic that drives data to the output pins
attempts to fetch data from the FIFO. When a FIFO underflow
condition occurs, incorrect data will be driven out on the
LCDC data pins.
Software should poll the FUF bit field in the LCD_STAT register
to check if an error condition has occurred or service the
interrupt if FUF_EN is enabled when FUF occurs. If the FUF bit
field has been set to 1, this will indicate an underflow
condition has occurred and then the software should execute a
reset of the LCDC via the LPSC.
This problem may occur if the LCDC FIFO threshold size
(LCDDMA_CTRL[TH_FIFO_READY]) is left at its default value after
reset. Increasing the FIFO threshold size will reduce or
eliminate underflows. Setting the threshold size to 256 double
words or larger is recommended.
Above issue is described in section 2.1.3 of silicon errata
http://www.ti.com/lit/er/sprz313e/sprz313e.pdf
Signed-off-by: Rajashekhara, Sudhakar <sudhakar.raj@ti.com>
Signed-off-by: Manjunathappa, Prakash <prakash.pm@ti.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
