If the driver is wedged, we can not issue the requests to exercise the
timelines or the system across suspend, so skip the tests. live_hangcheck
is there to fail if we cannot recover.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190413125820.14112-4-chris@chris-wilson.co.uk
The CrOS USB PD logging feature is logically separate functionality of
the charge manager, hence has its own driver. The driver logs the event
data for the USB PD charger available in some ChromeOS Embedded
Controllers.
Signed-off-by: Guenter Roeck <groeck@chromium.org>
[remove macro to APPEND_STRING and minor cleanups]
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
The software running on the Chrome OS Embedded Controller (cros_ec)
handles SPI transfers in a bit of a wonky way. Specifically if the EC
sees too long of a delay in a SPI transfer it will give up and the
transfer will be counted as failed. Unfortunately the timeout is
fairly short, though the actual number may be different for different
EC codebases.
We can end up tripping the timeout pretty easily if we happen to
preempt the task running the SPI transfer and don't get back to it for
a little while.
Historically this hasn't been a _huge_ deal because:
1. On old devices Chrome OS used to run PREEMPT_VOLUNTARY. That meant
we were pretty unlikely to take a big break from the transfer.
2. On recent devices we had faster / more processors.
3. Recent devices didn't use "cros-ec-spi-pre-delay". Using that
delay makes us more likely to trip this use case.
4. For whatever reasons (I didn't dig) old kernels seem to be less
likely to trip this.
5. For the most part it's kinda OK if a few transfers to the EC fail.
Mostly we're just polling the battery or doing some other task
where we'll try again.
Even with the above things, this issue has reared its ugly head
periodically. We could solve this in a nice way by adding reliable
retries to the EC protocol [1] or by re-designing the code in the EC
codebase to allow it to wait longer, but that code doesn't ever seem
to get changed. ...and even if it did, it wouldn't help old devices.
It's now time to finally take a crack at making this a little better.
This patch isn't guaranteed to make every cros_ec SPI transfer
perfect, but it should improve things by a few orders of magnitude.
Specifically you can try this on a rk3288-veyron Chromebook (which is
slower and also _does_ need "cros-ec-spi-pre-delay"):
md5sum /dev/zero &
md5sum /dev/zero &
md5sum /dev/zero &
md5sum /dev/zero &
while true; do
cat /sys/class/power_supply/sbs-20-000b/charge_now > /dev/null;
done
...before this patch you'll see boatloads of errors. After this patch I
don't see any in the testing I did.
The way this patch works is by effectively boosting the priority of
the cros_ec transfers. As far as I know there is no simple way to
just boost the priority of the current process temporarily so the way
we accomplish this is by queuing the work on the system_highpri_wq.
NOTE: this patch relies on the fact that the SPI framework attempts to
push the messages out on the calling context (which is the one that is
boosted to high priority). As I understand from earlier (long ago)
discussions with Mark Brown this should be a fine assumption. Even if
it isn't true sometimes this patch will still not make things worse.
[1] https://crbug.com/678675
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
The doubly unlock sequence at snd_seq_client_ioctl_unlock() is tricky.
I took a direct unref call since I thought it would avoid
misunderstanding, but rather this seems more confusing. Let's use
snd_seq_client_unlock() consistently even if they look strange to be
called twice, and add more comments for avoiding reader's confusion.
Fixes: 6b580f5231 ("ALSA: seq: Protect racy pool manipulation from OSS sequencer")
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Remove finish_tasklet. Requests that require DMA-unmapping or sdhci_reset
are completed either in the IRQ thread or a workqueue if the completion is
not initiated by the IRQ.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
In preparation for removing finish_tasklet, call mmc_request_done() from
the IRQ handler if possible. That will alleviate the potential loss of
performance from shifting away from finish_tasklet.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
In preparation for removing finish_tasklet, move some processing from
sdhci_request_done() to __sdhci_finish_mrq().
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
In preparation for removing finish_tasklet, move some functions.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
In preparation for removing finish_tasklet, reorganize sdhci_finish_mrq()
and __sdhci_finish_mrq() to separate the tasklet scheduling from other
processing.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Document devicetree bindings for stm32mp1 pwr regulators.
Signed-off-by: Pascal Paillet <p.paillet@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Fixes gcc '-Wunused-but-set-variable' warning:
drivers/memstick/host/jmb38x_ms.c: In function 'jmb38x_ms_issue_cmd':
drivers/memstick/host/jmb38x_ms.c:371:17: warning:
variable 'data' set but not used [-Wunused-but-set-variable]
It's never used since introduction and can be removed.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
pwrseq_emmc.c implements a HW reset procedure for eMMC chip by driving a
GPIO line.
It registers the .reset() cb on mmc_pwrseq_ops and it registers a system
restart notification handler; both of them perform reset by unconditionally
calling gpiod_set_value().
If the eMMC reset line is tied to a GPIO controller whose driver can sleep
(i.e. I2C GPIO controller), then the kernel would spit warnings when trying
to reset the eMMC chip by means of .reset() mmc_pwrseq_ops cb (that is
exactly what I'm seeing during boot).
Furthermore, on system reset we would gets to the system restart
notification handler with disabled interrupts - local_irq_disable() is
called in machine_restart() at least on ARM/ARM64 - and we would be in
trouble when the GPIO driver tries to sleep (which indeed doesn't happen
here, likely because in my case the machine specific code doesn't call
do_kernel_restart(), I guess..).
This patch fixes the .reset() cb to make use of gpiod_set_value_cansleep(),
so that the eMMC gets reset on boot without complaints, while, since there
isn't that much we can do, we avoid register the restart handler if the
GPIO controller has a sleepy driver (and we spit a dev_notice() message to
let people know)..
This had been tested on a downstream 4.9 kernel with backported
commit 83f37ee7ba33 ("mmc: pwrseq: Add reset callback to the struct
mmc_pwrseq_ops") and commit ae60fb031cf2 ("mmc: core: Don't do eMMC HW
reset when resuming the eMMC card"), because I couldn't boot my board
otherwise. Maybe worth to RFT.
Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
'top_base' memory region is optional. Check that the resource is valid
before using it. This avoid getting a "invalid resource" error message
printed by the kernel.
Signed-off-by: Fabien Parent <fparent@baylibre.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
DMA on this hardware is limited to dealing with a single page at a
time. Previously, the driver was set up accordingly to request single-page
DMA buffers, however that had the effect of generating a large number
of small MMC requests for data I/O.
Improve the driver to accept scatter-gather DMA buffers of larger sizes.
Iterate through those buffers a page at a time.
Testing with dd, this increases write performance from 2mb/sec to
10mb/sec, and increases read performance from 4mb/sec to 14mb/sec.
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
According to the AM654x Data Manual[1], the setup timing in lower speed
modes can only be met if the controller uses a falling edge data launch.
To ensure this, the HIGH_SPEED_ENA (HOST_CONTROL[2]) bit should be
cleared in default speed, SD high speed, MMC high speed, SDR12 and SDR25
speed modes.
Use the sdhci writeb callback to implement this condition.
[1] http://www.ti.com/lit/gpn/am6546 Section 5.10.5.16.1
Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The amount of changes to the memorystick subsystem are limited as of today.
However, I have a couple of times been funneling changes through my MMC
tree and it have turned out fine. So, I am here by volunteering to continue
doing this, by adding myself and the link to the MMC tree to the MEMSTICK
section.
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Alex Dubov <alex.dubov@gmail.com>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: Rui Feng <rui_feng@realsil.com.cn>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Maxim Levitsky <maximlevitsky@gmail.com>
The current SONY MEMORYSTICK CARD SUPPORT section is pointing to the TI
flash media memorystick driver, which is a bit confusing. Let's make this
more clear by moving this part into TI FLASH MEDIA INTERFACE DRIVER
section, but rename the section to TI FLASH MEDIA MEMORYSTICK/MMC DRIVERS,
as to make it more clear.
Finally, add Alex Dubov to the SONY MEMORYSTICK STANDARD SUPPORT, as I
believe that has been the intention.
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Alex Dubov <alex.dubov@gmail.com>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reduce size of duplicated comments by switching to use SPDX identifier.
No functional change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
- spaces surrounding arithmetic operators
- utilize full line limit
- drop extra spaces / TABs in variable definitions
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
For easy grepping on debug purposes join string literals back in
the messages.
No functional change.
While here, join list of module authors as well.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The mmc pointer can't be NULL at ->remove(), drop the useless check.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Driver core sets it to NULL upon probe failure or release.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch allows to get datactrl configuration specific
at variant. This introduce more flexibility on datactlr
value.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch defines get_dctrl_cfg callback for sdmmc variant.
sdmmc variant has specific stm32 transfer modes.
sdmmc data transfer mode selection could be:
-Block data transfer ending on block count.
-SDIO multibyte data transfer.
-MMC Stream data transfer (not used).
-Block data transfer ending with STOP_TRANSMISSION command.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch defines get_dctrl_cfg callback for qcom variant.
qcom variant has a specific block size definition.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds get_datactrl_cfg callback in mmci_host_ops
to allow to get datactrl configuration specific at variant.
Common helper function is defined and could be call by variant.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Enable the DMA codepath for writes as well as reads.
This improves write speed from 1mb/sec to 2mb/sec (tested with dd).
The original ampe_stor vendor driver also uses DMA for writes.
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Direct commands (DCMDs) are an optional feature of eMMC 5.1's command
queue engine (CQE). The Arasan eMMC 5.1 controller uses the CQHCI,
which exposes a control register bit to enable the feature.
The current implementation sets this bit unconditionally.
This patch allows to suppress the feature activation,
by specifying the property disable-cqe-dcmd.
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Fixes: 84362d79f4 ("mmc: sdhci-of-arasan: Add CQHCI support for arasan,sdhci-5.1")
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Add disable-cqe-dcmd as optional property for MMC hosts.
This property allows to disable or not enable the direct command
features of the command queue engine.
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Fixes: 84362d79f4 ("mmc: sdhci-of-arasan: Add CQHCI support for arasan,sdhci-5.1")
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Fix sparse warning:
drivers/mmc/host/sdhci-omap.c:788:6: warning:
symbol 'sdhci_omap_reset' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Faiz Abbas <faiz_abbas@ti.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tegra CQHCI/SDHCI design prevents write access to SDHCI block size
register when CQE is enabled and unhalted.
CQHCI driver enables CQE prior to invoking sdhci_cqe_enable which
violates this Tegra specific host requirement.
This patch fixes this by configuring sdhci block registers prior
to CQE unhalt.
This patch also has a fix for retry of unhalt due to known Tegra
specific CQE resume bug where first unhalt might not succeed when
clear all tasks is performed prior to resume and need a second unhalt.
This patch also includes CQE enable fix for CMD CRC errors that
happen with the specific sandisk emmc device when status command
is sent during the transfer of last data block due to marginal timing.
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds define for CBC field mask of the register
CQHCI_SSC1.
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tegra186 CQHCI host has a known bug where CQHCI controller selects
DATA_PRESENT_SELECT bit to 1 for DCMDs with R1B response type and
since DCMD does not trigger any data transfer, DCMD task complete
happens leaving the DATA FSM of host controller in wait state for
the data.
This effects the data transfer tasks issued after the DCMDs with
R1b response type resulting in timeout.
SW WAR is to set CMD_TIMING to 1 in DCMD task descriptor. This bug
and SW WAR is applicable only for Tegra186 and not for Tegra194.
This patch implements this WAR thru NVQUIRK_CQHCI_DCMD_R1B_CMD_TIMING
for Tegra186 and also implements update_dcmd_desc of cqhci_host_ops
interface to set CMD_TIMING bit depending on the NVQUIRK.
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Ritesh Harjani <riteshh@codeaurora.org>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds update_dcmd_desc interface to cqhci_host_ops to
allow hosts to update any of the DCMD task descriptor attributes
and parameters.
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Ritesh Harjani <riteshh@codeaurora.org>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
SDHCI controller of Tegra194 is similar to SDHCI controller in Tegra186.
This patch documents Tegra194 sdhci compatible string.
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch includes below HW tuning related fixes.
configures tuning parameters as per Tegra TRM
WAR fix for manual tap change
HW auto-tuning post process
As per Tegra TRM, SDR50 mode tuning execution takes upto maximum
of 256 tuning iterations and SDR104/HS200/HS400 modes tuning
execution takes upto maximum of 128 tuning iterations.
This patch programs tuning control register with maximum tuning
iterations needed based on the timing along with the start tap,
multiplier, and step size used by the HW tuning.
Tegra210 has a known issue of glitch on trimmer output when the
tap value is changed with the trimmer input clock running and the
WAR is to disable card clock before sending tuning command and
after sending tuning command wait for 1usec and issue SW reset
followed by enabling card clock.
This WAR is applicable when changing tap value manually as well.
Tegra SDHCI driver has this implemented correctly for manual tap
change but missing SW reset before enabling card clock during
sending tuning command.
Issuing SW reset during tuning command as a part of WAR and is
applicable in cases where tuning is performed with single step size
for more iterations. This patch includes this fix.
HW auto-tuning finds the best largest passing window and sets the
tap at the middle of the window. With some devices like sandisk
eMMC driving fast edges and due to high tap to tap delay in the
Tegra chipset, auto-tuning does not detect falling tap between the
valid windows resulting in a parital window or a merged window and
the best tap is set at the signal transition which is actually the
worst tap location.
Recommended SW solution is to detect if the best passing window
picked by the HW tuning is a partial or a merged window based on
min and max tap delays found from chip characterization across
PVT and perform tuning correction to pick the best tap.
This patch has implementation of this post HW tuning process for
the tegra hosts that support HW tuning through the callback function
tegra_sdhci_execute_hw_tuning and uses the tuned tap delay.
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
As per the Host Controller Standard Specification Version 4.20,
limitation of tuning iteration count is removed as PLL locking
time can be longer than UHS-1 tuning due to larger PVT fluctuation
and it will result in increase of tuning iteration to complete the
tuning.
This patch creates sdhci_host member tuning_loop_count to allow
hosts to specify maximum tuning iterations and also updates
execute_tuning to use this specified maximum tuning iteration count.
Default tuning_loop_count is set to same as existing loop count of
MAX_TUNING_LOOP which is 40 iterations.
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
ddr_signaling is set to true for DDR50 and DDR52 modes but is
not set back to false for other modes. This programs incorrect
host clock when mode change happens from DDR52/DDR50 to other
SDR or HS modes like incase of mmc_retune where it switches
from HS400 to HS DDR and then from HS DDR to HS mode and then
to HS200.
This patch fixes the ddr_signaling to set properly for non DDR
modes.
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Cc: stable@vger.kernel.org # v4.20 +
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The CBSY flag should be proper before calling tmio_mmc_host_probe()
because this function will already use write16 which checks this bit.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
max_req_size is calculated by 'max_blk_size * max_blk_count' in the TMIO
core. So, specifying U32_MAX as max_blk_count will overflow this
calculation. It will cause no harm in practice because the immense high
number will overflow into another immense high number. However, it is
not good coding practice, so calculate max_blk_count so that
max_req_size will fit into unsigned int on ARM32/64.
Thanks to the Renesas BSP team for the bug report!
Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
We will need it later for other calculations.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Mostly year updates, but one addition as well.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
According to the i.MX23/28 reference manuals both mmc interfaces support
the MMC_ERASE command. So enable this capability in the driver to allow
erase/discard/trim requests.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>