In order for the reset count to be accurate across our selftest, we need
to prevent the background retire worker from modifying our expected
state. To preserve the intent of symmetry, we apply this to both
i915_reset and i915_reset_engine, even though it strictly only affects
i915_reset_engine currently.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190626134433.6318-1-chris@chris-wilson.co.uk
Currently, if the user specifies an unsupported mitigation strategy on the
kernel command line, it will be ignored silently. The code will fall back
to the default strategy, possibly leaving the system more vulnerable than
expected.
This may happen due to e.g. a simple typo, or, for a stable kernel release,
because not all mitigation strategies have been backported.
Inform the user by printing a message.
Fixes: 98af845294 ("cpu/speculation: Add 'mitigations=' cmdline option")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190516070935.22546-1-geert@linux-m68k.org
Since we're working on moving stuff out of tools/perf/util/ to
tools/lib/, take the opportunity to adopt routines from the kernel that
are equivalent, so that tools/ code look more like the kernel.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-zqy1zdu2ok17qvi0ytk8z13c@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If LFP backlight type setting from VBT was "VESA eDP AUX Interface".
Driver should check panel capability and try to initialize aux backlight.
No matter i915_modparams.enable_dpcd_backlight was enabled or not.
v2: access dev_priv->vbt.backlight.type directly and remove unused function.
v3: 1. Modify i915.enable_dpcd_backlight type from bool to int and give default
value as 0 (disable).
2. Add a judgement to check LFP backlight type was aux interface or not.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Jose Roberto de Souza <jose.souza@intel.com>
Cc: Cooper Chiou <cooper.chiou@intel.com>
Signed-off-by: Lee Shawn C <shawn.c.lee@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1561045456-12171-1-git-send-email-shawn.c.lee@intel.com
- Rewrite of the davinci timer resulting to an immutable branch to be
shared with davinci platform specific tree (Bartosz Golaszewski)
- Cleanup and improvements of the tegra timer (Dmitry Osipenko)
- Add new nxp system counter timer (Bai Ping)
- Increase priority for exynos_mct to take over the initialization
of the IP the arch ARM timer depends on (Marek Szyprowski)
- Change macro use _BITUL() by BIT() on arc timer (Masahiro Yamada)
- Implement the delay timer on ixp4xx (Linus Walleij)
- Add the SPDX license identifier on the meson timer (Neil Armstrong)
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Merge tag 'timers-v5.4' of https://git.linaro.org/people/daniel.lezcano/linux into timers/core
Pull clocksource/events updates from Daniel Lezcano:
- Rewrite of the davinci timer resulting to an immutable branch to be
shared with davinci platform specific tree (Bartosz Golaszewski)
- Cleanup and improvements of the tegra timer (Dmitry Osipenko)
- Add new nxp system counter timer (Bai Ping)
- Increase priority for exynos_mct to take over the initialization
of the IP the arch ARM timer depends on (Marek Szyprowski)
- Change macro use _BITUL() by BIT() on arc timer (Masahiro Yamada)
- Implement the delay timer on ixp4xx (Linus Walleij)
- Add the SPDX license identifier on the meson timer (Neil Armstrong)
No change in behaviour, just using the same kernel idiom for such
operation.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-a85lkptkt0ru40irpga8yf54@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The bits set in x86_spec_ctrl_mask are used to calculate the guest's value
of SPEC_CTRL that is written to the MSR before VMENTRY, and control which
mitigations the guest can enable. In the case of SSBD, unless the host has
enabled SSBD always on mode (by passing "spec_store_bypass_disable=on" in
the kernel parameters), the SSBD bit is not set in the mask and the guest
can not properly enable the SSBD always on mitigation mode.
This has been confirmed by running the SSBD PoC on a guest using the SSBD
always on mitigation mode (booted with kernel parameter
"spec_store_bypass_disable=on"), and verifying that the guest is vulnerable
unless the host is also using SSBD always on mode. In addition, the guest
OS incorrectly reports the SSB vulnerability as mitigated.
Always set the SSBD bit in x86_spec_ctrl_mask when the host CPU supports
it, allowing the guest to use SSBD whether or not the host has chosen to
enable the mitigation in any of its modes.
Fixes: be6fcb5478 ("x86/bugs: Rework spec_ctrl base and mask logic")
Signed-off-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: bp@alien8.de
Cc: rkrcmar@redhat.com
Cc: kvm@vger.kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1560187210-11054-1-git-send-email-alejandro.j.jimenez@oracle.com
No change in behaviour intended.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-lcywlfqbi37nhegmhl1ar6wg@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
No change in behaviour intended, trivial optimization done by avoiding
looking for spaces in 'g' right after setting it to "No_group".
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-f2siadtp3hb5o0l1w7bvd8bk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
No change in behaviour.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-p9rtamq7lvre9zhti70azfwe@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The skip_sep() routine has the same implementation as skip_spaces(),
recently adopted from the kernel, sources, switch to it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-0ix211a81z2016dl5nmtdci4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Before suspending, mtk-eint would set the interrupt mask to the
one in wake_mask. However, some of these interrupts may not have a
corresponding interrupt handler, or the interrupt may be disabled.
On resume, the eint irq handler would trigger nevertheless,
and irq/pm.c:irq_pm_check_wakeup would be called, which would
try to call irq_disable. However, if the interrupt is not enabled
(irqd_irq_disabled(&desc->irq_data) is true), the call does nothing,
and the interrupt is left enabled in the eint driver.
Especially for level-sensitive interrupts, this will lead to an
interrupt storm on resume.
If we detect that an interrupt is only in wake_mask, but not in
cur_mask, we can just mask it out immediately (as mtk_eint_resume
would do anyway at a later stage in the resume sequence, when
restoring cur_mask).
Fixes: bf22ff45be ("genirq: Avoid unnecessary low level irq function calls")
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Acked-by: Sean Wang <sean.wang@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The following sparse warning is emitted:
arch/x86/kernel/crash.c:59:15:
warning: symbol 'crash_zero_bytes' was not declared. Should it be static?
The variable is only used in this compilation unit, but it is also only
used when CONFIG_KEXEC_FILE is enabled. Just making it static would result
in a 'defined but not used' warning for CONFIG_KEXEC_FILE=n.
Make it static and move it into the existing CONFIG_KEXEC_FILE section.
[ tglx: Massaged changelog and moved it into the existing ifdef ]
Fixes: dd5f726076 ("kexec: support for kexec on panic using new system call")
Signed-off-by: Tiezhu Yang <kernelpatch@126.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: kexec@lists.infradead.org
Cc: vgoyal@redhat.com
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: https://lkml.kernel.org/r/117ef0c6.3d30.16b87c9cfbf.Coremail.kernelpatch@126.com
The authentication can be circumvented, by design, by using the render
node.
From the driver POV there is no distinction between primary and render
nodes, thus we can drop the token.
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: virtualization@lists.linux-foundation.org
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190527081741.14235-12-emil.l.velikov@gmail.com
The authentication can be circumvented, by design, by using the render
node.
From the driver POV there is no distinction between primary and render
nodes, thus we can drop the token.
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190527081741.14235-11-emil.l.velikov@gmail.com
The authentication can be circumvented, by design, by using the render
node.
From the driver POV there is no distinction between primary and render
nodes, thus we can drop the token.
Note: the outstanding DRM_AUTH instance is:
- (badly coped) legacy DRI1 ioctl, which is a noop
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190527081741.14235-9-emil.l.velikov@gmail.com
The authentication can be circumvented, by design, by using the render
node.
From the driver POV there is no distinction between primary and render
nodes, thus we can drop the token.
Note: the outstanding DRM_AUTH instance is:
- legacy DRI1 ioctl, which is already neutered
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: nouveau@lists.freedesktop.org
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190527081741.14235-8-emil.l.velikov@gmail.com
The authentication can be circumvented, by design, by using the render
node.
From the driver POV there is no distinction between primary and render
nodes, thus we can drop the token.
Cc: Rob Clark <robdclark@gmail.com>
Cc: Sean Paul <sean@poorly.run>
Cc: freedreno@lists.freedesktop.org
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190527081741.14235-7-emil.l.velikov@gmail.com
The authentication can be circumvented, by design, by using the render
node.
From the driver POV there is no distinction between primary and render
nodes, thus we can drop the token.
Cc: Qiang Yu <yuq825@gmail.com>
Cc: lima@lists.freedesktop.org
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190527081741.14235-6-emil.l.velikov@gmail.com
The authentication can be circumvented, by design, by using the render
node.
From the driver POV there is no distinction between primary and render
nodes, thus we can drop the token.
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Inki Dae <inki.dae@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190527081741.14235-4-emil.l.velikov@gmail.com
The authentication can be circumvented, by design, by using the render
node.
From the driver POV there is no distinction between primary and render
nodes, thus we can drop the token.
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: etnaviv@lists.freedesktop.org
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190527081741.14235-3-emil.l.velikov@gmail.com
Currently vmw_execbuf_ioctl() open-codes the permission checking, size
extending and copying that is already done in core drm.
Kill all the duplication, adding a few comments for clarity.
Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Tested-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190522164119.24139-3-emil.l.velikov@gmail.com
According to the docs - prevents firstopen/lastclose races. Yet never
used in practise.
Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190522164119.24139-2-emil.l.velikov@gmail.com
Core DRM is safe when the callback is NULL.
Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190522164119.24139-1-emil.l.velikov@gmail.com
Fix sparse warning:
net/core/xdp.c:88:6: warning:
symbol '__mem_id_disconnect' was not declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
J721E SoCs have same I2C IP as OMAP SoCs. Add new compatible to
handle J721E SoCs.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently, each xdp samples are inconsistent in the use.
Most of the samples fetch the interface with it's name.
(ex. xdp1, xdp2skb, xdp_redirect_cpu, xdp_sample_pkts, etc.)
But some of the xdp samples are fetching the interface with
ifindex by command argument.
This commit enables xdp samples to fetch interface with it's name
without changing the original index interface fetching.
(<ifname|ifindex> fetching in the same way as xdp_sample_pkts_user.c does.)
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Switch the DT binding to a YAML schema to enable the DT validation.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Switch the DT binding to a YAML schema to enable the DT validation.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch adds a driver for the I2C controller found on the MediaTek
MT7621/7628/7688 SoC's. The base version of this driver was done by
Steven Liu (according to the copyright and MODULE_AUTHOR lines). It
can be found in the OpenWRT repositories (v4.14 at the time I looked).
The base driver had many issues, which are disccussed here:
https://en.forum.labs.mediatek.com/t/openwrt-15-05-loads-non-working-i2c-kernel-module-for-mt7688/1286/3
>From this link an enhanced driver version (complete rewrite, mayor
changes: support clock stretching, repeated start, ACK handling and
unlimited message length) from Jan Breuer can be found here:
https://gist.github.com/j123b567/9b555b635c2b4069d716b24198546954
This patch now adds this enhanced I2C driver to mainline.
Changes by Stefan Roese for upstreaming:
- Add devicetree bindings
- checkpatch clean
- Use module_platform_driver()
- Minor cosmetic enhancements
- Removed IO warpped functions
- Use readl_relaxed_poll_timeout() and drop poll_down_timeout()
- Removed superfluous barrier() in mtk_i2c_reset()
- Use i2c_8bit_addr_from_msg()
- Added I2C_FUNC_PROTOCOL_MANGLING
- Removed adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
Signed-off-by: Stefan Roese <sr@denx.de>
Tested-by: René van Dorst <opensource@vdorst.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add bindings for the I2C controller that can be found in the MediaTek
MT7621/7628/7688 SoCs.
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
We are using sysfs functions directly, so we should include the header.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Probe function fails to recognize that upstream clock actually
doesn't yet exist because clock driver has not been initialized.
Actually try to go get the clock and test for its existence
before trying to set up a downstream clock based upon it.
This fixes a bug that causes the i2c driver not to work with
monolithic kernels.
Fixes: bebff81fb8 ("i2c: bcm2835: Model Divider in CCF")
Signed-off-by: Annaliese McDermond <nh6z@nh6z.net>
Acked-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If any of the clock code in the probe fails and returns, the IRQ
will not be freed. Moving the IRQ request to last allows it to
be freed on any errors further up in the probe function. devm_
calls can apparently not be used because there are some potential
race conditions that will arise.
Fixes: bebff81fb8 ("i2c: bcm2835: Model Divider in CCF")
Signed-off-by: Annaliese McDermond <nh6z@nh6z.net>
Acked-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Nobody (including me) noticed that these functions were exported but not
added to the header :/
Fixes: 7159dbdae3 ("i2c: core: improve return value handling of i2c_new_device and i2c_new_dummy")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The decoder is flawed in the following ways:
- The decoder sometimes fails silently, i.e. it announces success but
returns a word that is not a codeword.
- The return value of the decoder is incoherent with respect to how
fixed erasures are counted. If the word to be decoded is a codeword,
then the decoder always returns zero even if some erasures are given.
On the other hand, if the word to be decoded contains errors, then the
number of erasures is always included in the count of corrected
symbols. So the decoder handles erasures without symbol corruption
inconsistently. This inconsistency probably doesn't affect anyone
using the decoder, but it is inconsistent with the documentation.
- The error positions returned in eras_pos include all erasures, but the
corrections are only set in the correction buffer if there actually is
a symbol error. So if there are erasures without symbol corruption,
then the correction buffer will contain errors (unless initialized to
zero before calling the decoder) or some values will be unset (if the
correction buffer is uninitialized).
- When correcting data in-place the decoder does not correct errors in
the parity. On the other hand, when returning the errors in correction
buffers, errors in the parity are included.
The respective fixed are:
- The syndrome of a codeword is always zero, and the syndrome is linear,
.i.e, S(x+e) = S(x) + S(e). So compute the syndrome for the error and
check whether it equals the syndrome of the received word. If it does,
then we have decoded to a valid codeword, otherwise we know that we
have an uncorrectable error. Fortunately, some unrecoverable error
conditions can be detected earlier in the decoding, which saves some
processing power.
- Simply count and return the number of symbols actually corrected.
- Make sure to only return positions where symbols were corrected.
- Also fix errors in parity when correcting in-place. Another option
would be to completely disregard errors in the parity, but then the
interface makes it impossible to write tests that test for silent
failures.
Other changes:
- Only fill the correction buffer and error position buffer if both of
them are provided. Otherwise correct in place. Previously the error
position buffer was always populated with the positions of the
corrected errors, irrespective of whether a correction buffer was
supplied or not. The rationale for this change is that there seems to
be two use cases for the decoder; correct in-place or use the
correction buffers. The caller does not need the positions of the
corrected errors when in-place correction is used. If in-place
correction is not used, then both the correction buffer and error
position buffer need to be populated.
Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190620141039.9874-8-ferdinand.blomqvist@gmail.com
The decoder returns the number of corrected symbols, not bits.
The caller provided syndrome must be in index form.
Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190620141039.9874-7-ferdinand.blomqvist@gmail.com
Nothing useful was done after the finish label when count is negative so
return directly instead of jumping to finish.
Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190620141039.9874-5-ferdinand.blomqvist@gmail.com
The length of the data load must be at least one. Or in other words,
there must be room for at least 1 data and nroots parity symbols after
shortening the RS code.
Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190620141039.9874-4-ferdinand.blomqvist@gmail.com
The decoding of shortenend codes is broken. It only works as expected if
there are no erasures.
When decoding with erasures, Lambda (the error and erasure locator
polynomial) is initialized from the given erasure positions. The pad
parameter is not accounted for by the initialisation code, and hence
Lambda is initialized from incorrect erasure positions.
The fix is to adjust the erasure positions by the supplied pad.
Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190620141039.9874-3-ferdinand.blomqvist@gmail.com
A Reed-Solomon code with minimum distance d can correct any error and
erasure pattern that satisfies 2 * #error + #erasures < d. If the
error correction capacity is exceeded, then correct decoding cannot be
guaranteed. The decoder must, however, return a valid codeword or report
failure.
There are two main tests:
- Check for correct behaviour up to the error correction capacity
- Check for correct behaviour beyond error corrupted capacity
Both tests are simple:
1. Generate random data
2. Encode data with the chosen code
3. Add errors and erasures to data
4. Decode the corrupted word
5. Check for correct behaviour
When testing up to capacity we test for:
- Correct decoding
- Correct return value (i.e. the number of corrected symbols)
- That the returned error positions are correct
There are two kinds of erasures; the erased symbol can be corrupted or
not. When counting the number of corrected symbols, erasures without
symbol corruption should not be counted. Similarly, the returned error
positions should only include positions where a correction is necessary.
We run the up to capacity tests for three different interfaces of
decode_rs:
- Use the correction buffers
- Use the correction buffers with syndromes provided by the caller
- Error correction in place (does not check the error positions)
When testing beyond capacity test for silent failures. A silent failure is
when the decoder returns success but the returned word is not a valid
codeword.
There are a couple of options for the tests:
- Verbosity.
- Whether to test for correct behaviour beyond capacity. Default is to
test beyond capacity.
- Whether to allow erasures without symbol corruption. Defaults to yes.
Note that the tests take a couple of minutes to complete.
Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190620141039.9874-2-ferdinand.blomqvist@gmail.com
The Boe Himax8279d is a 8.0" panel with a 1200x1920 resolution and
connected to DSI using four lanes.
V8:
- Modify communication address
V7:
- Add the information of the reviewer
V6:
- Add the information of the reviewer
V5:
- Added changelog
V4:
- None
V3:
- None
V2:
- Add compatible device "boe,himax8279d10p" (Sam)
- Add the necessary property descriptions (Sam)
Signed-off-by: Jerry Han <jerry.han.hq@gmail.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Derek Basehore <dbasehore@chromium.org>
Cc: Jitao Shi <jitao.shi@mediatek.com>
Cc: Rock wang <rock_wang@himax.com.cn>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190425031842.17202-1-jerry.han.hq@gmail.com
