Add 2 early command line parameters that allow to downgrade satp mode
(using the same naming as x86):
- "no5lvl": use a 4-level page table (down from sv57 to sv48)
- "no4lvl": use a 3-level page table (down from sv57/sv48 to sv39)

Note that going through the device tree to get the kernel command line
works with ACPI too since the efi stub creates a device tree anyway with
the command line.

In KASAN kernels, we can't use the libfdt that early in the boot process
since we are not ready to execute instrumented functions. So instead of
using the "generic" libfdt, we compile our own versions of those functions
that are not instrumented and that are prefixed so that they do not
conflict with the generic ones. We also need the non-instrumented versions
of the string functions and the prefixed versions of memcpy/memmove.

This is largely inspired by commit aacd149b ("arm64: head: avoid
relocating the kernel twice for KASLR") from which I removed compilation
flags that were not relevant to RISC-V at the moment (LTO, SCS). Also
note that we have to link with -z norelro to avoid ld.lld to throw a
warning with the new .got sections, like in commit 311bea3c ("arm64:
link with -z norelro for LLD or aarch64-elf").

Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20230424092313.178699-2-alexghiti@rivosinc.com


Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

Dumping the dtb from new versions of QEMU warns that sv57 is an
undocumented mmu-type. The kernel has supported sv57 for about a year,
so bring it into the fold.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230424-rival-habitual-478567c516f0@spud


Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

This allows userspace to select various routines to use based on the
performance of misaligned access on the target hardware.

Rather than adding DT bindings, this change taps into the alternatives
mechanism used to probe CPU errata. Add a new function pointer alongside
the vendor-specific errata_patch_func() that probes for desirable errata
(otherwise known as "features"). Unlike the errata_patch_func(), this
function is called on each CPU as it comes up, so it can save
feature information per-CPU.

The T-head C906 has fast unaligned access, both as defined by GCC [1],
and in performing a basic benchmark, which determined that byte copies
are >50% slower than a misaligned word copy of the same data size (source
for this test at [2]):

bytecopy size f000 count 50000 offset 0 took 31664899 us
wordcopy size f000 count 50000 offset 0 took 5180919 us
wordcopy size f000 count 50000 offset 1 took 13416949 us

[1] https://github.com/gcc-mirror/gcc/blob/master/gcc/config/riscv/riscv.cc#L353
[2] https://pastebin.com/EPXvDHSW



Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Evan Green <evan@rivosinc.com>
Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Paul Walmsley <paul.walmsley@sifive.com>
Link: https://lore.kernel.org/r/20230407231103.2622178-5-evan@rivosinc.com


Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

We have an implicit set of base behaviors that userspace depends on,
which are mostly defined in various ISA specifications.

Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Evan Green <evan@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Reviewed-by: Paul Walmsley <paul.walmsley@sifive.com>
Link: https://lore.kernel.org/r/20230407231103.2622178-4-evan@rivosinc.com


Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

We don't have enough space for these all in ELF_HWCAP{,2} and there's no
system call that quite does this, so let's just provide an arch-specific
one to probe for hardware capabilities.  This currently just provides
m{arch,imp,vendor}id, but with the key-value pairs we can pass more in
the future.

Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Evan Green <evan@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Reviewed-by: Paul Walmsley <paul.walmsley@sifive.com>
Link: https://lore.kernel.org/r/20230407231103.2622178-3-evan@rivosinc.com


Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

The Zicboz operation (cbo.zero) operates on a block-size defined
for the cpu-core. While we already have the riscv,cbom-block-size
property, it only provides the block size for Zicbom operations.
Even though it's likely Zicboz and Zicbom will use the same size,
that's not required by the specification. Create another property
specifically for Zicboz.

Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230224162631.405473-4-ajones@ventanamicro.com


Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

MT7621 SoC provides a system controller node for accessing to some registers.
Add a phandle in this node to avoid using MIPS related arch operations and
includes in watchdog driver code.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230214103936.1061078-2-sergio.paracuellos@gmail.com


Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

PDMC can work with different types of microphones, thus different boards
could have different microphones. Depending on microphone type the PDMC
would need to wait longer or shorter period (at startup) than the default
chosen one to filter unwanted noise. Thus add microchip,startup-delay-us
binding to let PDMC users to specify startup delay.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230228110145.3770525-3-claudiu.beznea@microchip.com


Signed-off-by: Mark Brown <broonie@kernel.org>

Explain why STIBP is needed with legacy IBRS as currently implemented
(KERNEL_IBRS) and why STIBP is not needed when enhanced IBRS is enabled.

Fixes: 7c693f54 ("x86/speculation: Add spectre_v2=ibrs option to support Kernel IBRS")
Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230227060541.1939092-2-kpsingh@kernel.org

Long long ago, in a more innocent time, Greg wrote the clarification for
how the DCO should work and that you couldn't make anonymous
contributions, because the sign-off needed to be something we could
check back with.

It was 2006, and nobody reacted to the wording, the whole Facebook 'real
name' controversy was a decade in the future, and nobody even thought
about it.  And despite the language, we've always accepted nicknames and
that language was never meant to be any kind of exclusionary wording.

In fact, even when it became a discussion in other adjacent projects,
apparently nobody even thought to just clarify the language in the
kernel docs, and instead we had projects like the CNCF that had long
discussions about it, and wrote their own clarifications [1] of it.

Just simplify the wording to the point where it shouldn't be causing
unnecessary angst and pain, or scare away people who go by preferred
naming.

Link: https://github.com/cncf/foundation/blob/659fd32c86dc/dco-guidelines.md

 [1]
Fixes: af45f32d ("We can not allow anonymous contributions to the kernel")
Acked-by: Greg KH <gregkh@linuxfoundation.org>
Acked-by: Michael Dolan <mdolan@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 596b0474 ("kbuild: preprocess module linker script")
removes KBUILD_LDS_MODULE, yet the variable is still mentioned in
kbuild documentation. Remove the reference to the now-nonexistent
variable.

Signed-off-by: Sangmoon Kim <sangmoon.kim@samsung.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

On many Qualcomm platforms the PMIC RTC control and time registers are
read-only so that the RTC time can not be updated. Instead an offset
needs be stored in some machine-specific non-volatile memory, which a
driver can take into account.

Add an 'offset' nvmem cell which can be used to store a 32-bit offset
from the Unix epoch so that the RTC time can be updated on such
platforms.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: David Collins <quic_collinsd@quicinc.com>
Link: https://lore.kernel.org/r/20230202155448.6715-17-johan+linaro@kernel.org


Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Replace "sendpage" with "sendfile". Remove comment about
ENOBUFS when the sockopt hasn't been set; experimentation
indicates that this is not true.

Signed-off-by: nick black <dankamongmen@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/Y/gg/EhIIjugLdd3@schwarzgerat.orthanc


Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Revise RT9467 compatible name from "richtek,rt9467-charger" to
"richtek,rt9467" because it has to match the "compatible name" in
the source code.

Fixes: e1b4620f ("dt-bindings: power: supply: Add Richtek RT9467 battery charger")
Reported-by: Rob Herring <robh@kernel.org>
Signed-off-by: ChiaEn Wu <chiaen_wu@richtek.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Document how the absence of the "present" property in the sysfs
power_supply class should be handled.

Link: https://gitlab.freedesktop.org/upower/upower/-/merge_requests/173


Cc: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Fix a repeated copy/paste typo.

Fixes: d3d854fd ("netdev-genl: create a simple family for netdev stuff")
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Document the compatible for the QDU1000 mailbox.

Signed-off-by: Melody Olvera <quic_molvera@quicinc.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Add the mailbox compatible for the IPQ5332 SoC.

Since the IPQ5332 mailbox is compatible with the IPQ6018, lets create the
fallback to ipq6018 compatible, so that we don't bloat the of_device_id
table in the driver.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Kathiravan T <quic_kathirav@quicinc.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Convert Qualcomm G-Link RPM edge binding to DT schema.  Move it to
remoteproc as it better suits the purpose - communication channel with
remote processor.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Add the #clock-cells property to the MSM8996 example, as the APCS block
is going to provide the `sys_apcs_aux' clock to the consumers.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Add missing platforms to the conditional clauses selecting whether the
clocks/clock-names properties are required or whether they must be
omitted.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

The schema incorrectly lists some of the platforms in the statement
requiring clocks/clock-names. Correct this by moving platforms not
requiring additional clocks to the separate clause.

Fixes: 0d17014e ("dt-bindings: mailbox: Add binding for SDX55 APCS")
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

On msm8976 platform APCS also uses syscon compatible, so move it to the
block of compatibles using SoC-compat together with syscon.

Fixes: 60545466 ("dt-bindings: mailbox: qcom,apcs-kpss-global: Add syscon const for relevant entries")
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

The commit 0d17014e ("dt-bindings: mailbox: Add binding for SDX55
APCS") added SDX55 compatible string to one of clock-selection
conditions, but failed to add one to the main schema's compatible list.
Fix this omission.

Fixes: 0d17014e ("dt-bindings: mailbox: Add binding for SDX55 APCS")
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Add a compatible for the ipcc on sa8775p platforms.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Convert the sti-mailbox.txt file into st,sti-mailbox.yaml

Signed-off-by: Alain Volmat <avolmat@me.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Encourage developers to place Link: tag pointing to the report when they
are using Reported-by: tags. Those links are often extremely useful for
any code archaeologist that wants to know more about the backstory of a
change than the commit message provides. That includes maintainers
higher up in the patch-flow hierarchy, which is why Linus asks
developers to add such links [1, 2, 3]. To quote [1]:

> Again, the commit has a link to the patch *submission*, which is
> almost entirely useless. There's no link to the actual problem the
> patch fixes.
>
> [...]
>
> Put another way: I can see that
>
> Reported-by: Zhangfei Gao <zhangfei.gao@foxmail.com>
>
> in the commit, but I don't have a clue what the actual report was, and
> there really isn't enough information in the commit itself, except for
> a fairly handwavy "Device drivers might, for instance, still need to
> flush operations.."
>
> I don't want to know what device drivers _might_ do. I would want to
> have an actual pointer to what they do and where.

Another reason why these links are wanted: the ongoing regression
tracking efforts can only scale with them, as they allow the regression
tracking bot 'regzbot' to automatically connect tracked reports with
patches that are posted or committed to fix tracked regressions.

Link: https://lore.kernel.org/all/CAHk-=wjMmSZzMJ3Xnskdg4+GGz=5p5p+GSYyFBTh0f-DgvdBWg@mail.gmail.com/ [1]
Link: https://lore.kernel.org/all/CAHk-=wgs38ZrfPvy=nOwVkVzjpM3VFU1zobP37Fwd_h9iAD5JQ@mail.gmail.com/ [2]
Link: https://lore.kernel.org/all/CAHk-=wjxzafG-=J8oT30s7upn4RhBs6TX-uVFZ5rME+L5_DoJA@mail.gmail.com/

 [3]
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Link: https://lore.kernel.org/r/9a07ec640d809723492f8ade4f54705914e80419.1676369564.git.linux@leemhuis.info


Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Convert the Documentation front page to use the heading adornments
that are documented in doc-guide/sphinx.rst for document title and
chapters. I.e., convert most section headings to chapters.

This leaves "Indices and tables" as a chapter entry at the same level
as the other chapters.

The only visual difference from before to after is that the "Indices
and tables" heading is smaller and has more vertical whitespace
preceding it (although that may depend on the web browser being used).

Fixes: 0c7b4366 ("docs: Rewrite the front page")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/20230215005726.27320-1-rdunlap@infradead.org


Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Translate Documentation/process/programming-language.rst into Spanish.

Signed-off-by: Carlos Bilbao <carlos.bilbao@amd.com>
Link: https://lore.kernel.org/r/20230207220844.2661295-1-carlos.bilbao@amd.com


Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The config is actually called CONFIG_RT_MUTEXES, not CONFIG_RT_MUTEX.

The config CONFIG_LOCK_TORTURE_TEST should be connected by underscore, for
the sake of consistent referencing to configs in the kernel documentation.

Address those issues.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lore.kernel.org/r/20230220165749.12850-1-lukas.bulwahn@gmail.com


Signed-off-by: Jonathan Corbet <corbet@lwn.net>

These Real Time Clocks are managed by the rtc-pcf85363 device driver,
which now supports the quartz-load-femtofarads property.

Signed-off-by: Javier Carrasco <javier.carrasco@wolfvision.net>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230215081815.3141776-2-javier.carrasco@wolfvision.net


Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Document the qcom,tcsr-ipq5332 compatible.

Signed-off-by: Kathiravan T <quic_kathirav@quicinc.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230130170155.27266-2-quic_kathirav@quicinc.com

Add binding for NXP BBNSM(Battery-Backed Non-Secure Module).

Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230129070823.1945489-2-ping.bai@nxp.com

Document Mediatek mt8365-syscfg

Signed-off-by: Bernhard Rosenkränzer <bero@baylibre.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230125143503.1015424-4-bero@baylibre.com

Add Kinetic KTZ8866 backlight binding documentation.

Signed-off-by: Jianhua Lu <lujianhua000@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230120155018.15376-1-lujianhua000@gmail.com

Document the compatible for the wled block found in PMI8950.

Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20221101161801.1058969-1-luca@z3ntu.xyz

Simple syscon devices may require deassertion of a reset signal in order
to access their register set. This change adds the `resets` property from
reset.yaml#/properties/resets (referenced through core.yaml), specifying
a maxItems of 1 for a single (optional) reset descriptor.

This will allow a future change to the syscon driver to implement reset
control.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230105005010.124948-2-jk@codeconstruct.com.au

Add the AMD Pensando Elba SoC system registers compatible

Signed-off-by: Brad Larson <blarson@amd.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230119035136.21603-6-blarson@amd.com

Document the qcom,msm8226-tcsr compatible.

Signed-off-by: Matti Lehtimäki <matti.lehtimaki@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230112202612.791455-5-matti.lehtimaki@gmail.com

Document hpe,gxp-sysreg compatible for GXP registers.

Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20221216183532.78933-4-nick.hawkins@hpe.com