The downstream kernel employs the concept of "keeping the bus alive"
by voting for the minimum (XO/19.2MHz) rate at all times on certain
(well, most) buses. This is a very important thing to have, as if we
either have a lackluster/wrong DT that doesn't specify a (high enough)
vote on a certain bus, we may lose access to the entire bus altogether.
This is very apparent when we only start introducing interconnect
support on a given platform and haven't yet introduced voting on all
peripherals.
The same can happen if we only have a single driver casting a vote on
a certain bus and that driver exits/crashes/suspends.
The keepalive vote is limited to the ACTIVE bucket, as keeping a
permanent vote on the SLEEP one could prevent the platform from properly
entering low power mode states.
Introduce the very same concept, with a slight twist: the vendor
kernel checks whether the rate is zero before setting the minimum
vote, but that's rather silly, as in doing so we're at the mercy
of CCF. Instead, explicitly clamp the rates to always be >= 19.2 MHz
for providers with keep_alive=true.
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Acked-by: Georgi Djakov <djakov@kernel.org>
Link: https://lore.kernel.org/r/20230526-topic-smd_icc-v7-6-09c78c175546@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
On MSM8996 two CPU clusters are interconnected using the Core Bus
Fabric (CBF). In order for the CPU clusters to function properly, it
should be clocked following the core's frequencies to provide adequate
bandwidth.
Register CBF as a clock (required for CPU to boot) and add a tiny
interconnect layer on top of it to let cpufreq/opp scale the CBF clock.
* icc-cbf
dt-bindings: interconnect/msm8996-cbf: add defines to be used by CBF
interconnect: add clk-based icc provider support
clk: qcom: cbf-msm8996: scale CBF clock according to the CPUfreq
interconnect: icc-clk: fix modular build
Link: https://lore.kernel.org/r/20230512001334.2983048-1-dmitry.baryshkov@linaro.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
This was not allocating enough bytes. There are two issue here.
First, there was a typo where it was taking the size of the pointer
instead of the size of the struct, "sizeof(qp->intf_clks)" vs
"sizeof(*qp->intf_clks)". Second, it's an array of "cd_num" clocks so
we need to allocate space for more than one element.
Fixes: 2e2113c8a6 ("interconnect: qcom: rpm: Handle interface clocks")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/e0fa275c-ae63-4342-9c9e-0ffaf6314da1@kili.mountain
Signed-off-by: Georgi Djakov <djakov@kernel.org>
The interconnect driver is (or soon will be) vital to many other
devices, as it's not a given that the bootloader will set up enough
bandwidth for us or that the values we come into are reasonable.
Promote the driver to core_initcall to ensure the consumers (i.e.
most "meaningful" parts of the SoC) can probe without deferrals.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230228-topic-qos-v8-8-ee696a2c15a9@linaro.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Commit dd42ec8ea5 ("interconnect: qcom: rpm: Use _optional func for provider clocks")
relaxed the requirements around probing bus clocks. This was a decent
solution for making sure MSM8996 would still boot with old DTs, but
now that there's a proper fix in place that both old and new DTs
will be happy about, revert back to the safer variant of the
function.
Fixes: dd42ec8ea5 ("interconnect: qcom: rpm: Use _optional func for provider clocks")
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230228-topic-qos-v8-7-ee696a2c15a9@linaro.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
For SMD RPM bus scaling to work, we need a pair of sleep-wake clocks.
The variable number of them we previously supported was only a hack
to keep the clocks required for QoS register access, but now that
these are separated, we can leave bus_clks to the actual bus clocks.
In cases where there is no actual bus scaling (such as A0NoC on MSM8996
and GNoC on SDM660 where the HLOS is only supposed to program the QoS
registers and the bus is either static or controlled remotely), allow
for no clock scaling with a boolean property.
Remove all the code related to allowing an arbitrary number of bus_clks,
replace the number by BUS_CLK_MAX (= 2) and guard the bus clock paths
to ensure they are not taken on non-scaling buses.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230228-topic-qos-v8-6-ee696a2c15a9@linaro.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Some (but not all) providers (or their specific nodes) require
specific clocks to be turned on before they can be accessed. Failure
to ensure that results in a seemingly random system crash (which
would usually happen at boot with the interconnect driver built-in),
resulting in the platform not booting up properly.
Limit the number of bus_clocks to 2 (which is the maximum that SMD
RPM interconnect supports anyway) and handle non-scaling clocks
separately. Update MSM8996 and SDM660 drivers to make sure they do
not regress with this change.
This unfortunately has to be done in one patch to prevent either
compile errors or broken bisect.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230518195801.2556998-1-konrad.dybcio@linaro.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
For some devices it is useful to export clocks as interconnect providers,
if the clock corresponds to bus bandwidth.
For example, on MSM8996 the cluster interconnect clock should be scaled
according to the cluster frequencies. Exporting it as an interconnect
allows one to properly describe this as the cluster bandwidth
requirements.
Tested-by: Yassine Oudjana <y.oudjana@protonmail.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20230512001334.2983048-3-dmitry.baryshkov@linaro.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Pull module updates from Luis Chamberlain:
"The summary of the changes for this pull requests is:
- Song Liu's new struct module_memory replacement
- Nick Alcock's MODULE_LICENSE() removal for non-modules
- My cleanups and enhancements to reduce the areas where we vmalloc
module memory for duplicates, and the respective debug code which
proves the remaining vmalloc pressure comes from userspace.
Most of the changes have been in linux-next for quite some time except
the minor fixes I made to check if a module was already loaded prior
to allocating the final module memory with vmalloc and the respective
debug code it introduces to help clarify the issue. Although the
functional change is small it is rather safe as it can only *help*
reduce vmalloc space for duplicates and is confirmed to fix a bootup
issue with over 400 CPUs with KASAN enabled. I don't expect stable
kernels to pick up that fix as the cleanups would have also had to
have been picked up. Folks on larger CPU systems with modules will
want to just upgrade if vmalloc space has been an issue on bootup.
Given the size of this request, here's some more elaborate details:
The functional change change in this pull request is the very first
patch from Song Liu which replaces the 'struct module_layout' with a
new 'struct module_memory'. The old data structure tried to put
together all types of supported module memory types in one data
structure, the new one abstracts the differences in memory types in a
module to allow each one to provide their own set of details. This
paves the way in the future so we can deal with them in a cleaner way.
If you look at changes they also provide a nice cleanup of how we
handle these different memory areas in a module. This change has been
in linux-next since before the merge window opened for v6.3 so to
provide more than a full kernel cycle of testing. It's a good thing as
quite a bit of fixes have been found for it.
Jason Baron then made dynamic debug a first class citizen module user
by using module notifier callbacks to allocate / remove module
specific dynamic debug information.
Nick Alcock has done quite a bit of work cross-tree to remove module
license tags from things which cannot possibly be module at my request
so to:
a) help him with his longer term tooling goals which require a
deterministic evaluation if a piece a symbol code could ever be
part of a module or not. But quite recently it is has been made
clear that tooling is not the only one that would benefit.
Disambiguating symbols also helps efforts such as live patching,
kprobes and BPF, but for other reasons and R&D on this area is
active with no clear solution in sight.
b) help us inch closer to the now generally accepted long term goal
of automating all the MODULE_LICENSE() tags from SPDX license tags
In so far as a) is concerned, although module license tags are a no-op
for non-modules, tools which would want create a mapping of possible
modules can only rely on the module license tag after the commit
8b41fc4454 ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf").
Nick has been working on this *for years* and AFAICT I was the only
one to suggest two alternatives to this approach for tooling. The
complexity in one of my suggested approaches lies in that we'd need a
possible-obj-m and a could-be-module which would check if the object
being built is part of any kconfig build which could ever lead to it
being part of a module, and if so define a new define
-DPOSSIBLE_MODULE [0].
A more obvious yet theoretical approach I've suggested would be to
have a tristate in kconfig imply the same new -DPOSSIBLE_MODULE as
well but that means getting kconfig symbol names mapping to modules
always, and I don't think that's the case today. I am not aware of
Nick or anyone exploring either of these options. Quite recently Josh
Poimboeuf has pointed out that live patching, kprobes and BPF would
benefit from resolving some part of the disambiguation as well but for
other reasons. The function granularity KASLR (fgkaslr) patches were
mentioned but Joe Lawrence has clarified this effort has been dropped
with no clear solution in sight [1].
In the meantime removing module license tags from code which could
never be modules is welcomed for both objectives mentioned above. Some
developers have also welcomed these changes as it has helped clarify
when a module was never possible and they forgot to clean this up, and
so you'll see quite a bit of Nick's patches in other pull requests for
this merge window. I just picked up the stragglers after rc3. LWN has
good coverage on the motivation behind this work [2] and the typical
cross-tree issues he ran into along the way. The only concrete blocker
issue he ran into was that we should not remove the MODULE_LICENSE()
tags from files which have no SPDX tags yet, even if they can never be
modules. Nick ended up giving up on his efforts due to having to do
this vetting and backlash he ran into from folks who really did *not
understand* the core of the issue nor were providing any alternative /
guidance. I've gone through his changes and dropped the patches which
dropped the module license tags where an SPDX license tag was missing,
it only consisted of 11 drivers. To see if a pull request deals with a
file which lacks SPDX tags you can just use:
./scripts/spdxcheck.py -f \
$(git diff --name-only commid-id | xargs echo)
You'll see a core module file in this pull request for the above, but
that's not related to his changes. WE just need to add the SPDX
license tag for the kernel/module/kmod.c file in the future but it
demonstrates the effectiveness of the script.
Most of Nick's changes were spread out through different trees, and I
just picked up the slack after rc3 for the last kernel was out. Those
changes have been in linux-next for over two weeks.
The cleanups, debug code I added and final fix I added for modules
were motivated by David Hildenbrand's report of boot failing on a
systems with over 400 CPUs when KASAN was enabled due to running out
of virtual memory space. Although the functional change only consists
of 3 lines in the patch "module: avoid allocation if module is already
present and ready", proving that this was the best we can do on the
modules side took quite a bit of effort and new debug code.
The initial cleanups I did on the modules side of things has been in
linux-next since around rc3 of the last kernel, the actual final fix
for and debug code however have only been in linux-next for about a
week or so but I think it is worth getting that code in for this merge
window as it does help fix / prove / evaluate the issues reported with
larger number of CPUs. Userspace is not yet fixed as it is taking a
bit of time for folks to understand the crux of the issue and find a
proper resolution. Worst come to worst, I have a kludge-of-concept [3]
of how to make kernel_read*() calls for modules unique / converge
them, but I'm currently inclined to just see if userspace can fix this
instead"
Link: https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/ [0]
Link: https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com [1]
Link: https://lwn.net/Articles/927569/ [2]
Link: https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org [3]
* tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (121 commits)
module: add debugging auto-load duplicate module support
module: stats: fix invalid_mod_bytes typo
module: remove use of uninitialized variable len
module: fix building stats for 32-bit targets
module: stats: include uapi/linux/module.h
module: avoid allocation if module is already present and ready
module: add debug stats to help identify memory pressure
module: extract patient module check into helper
modules/kmod: replace implementation with a semaphore
Change DEFINE_SEMAPHORE() to take a number argument
module: fix kmemleak annotations for non init ELF sections
module: Ignore L0 and rename is_arm_mapping_symbol()
module: Move is_arm_mapping_symbol() to module_symbol.h
module: Sync code of is_arm_mapping_symbol()
scripts/gdb: use mem instead of core_layout to get the module address
interconnect: remove module-related code
interconnect: remove MODULE_LICENSE in non-modules
zswap: remove MODULE_LICENSE in non-modules
zpool: remove MODULE_LICENSE in non-modules
x86/mm/dump_pagetables: remove MODULE_LICENSE in non-modules
...
Since commit 8b41fc4454 ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations
are used to identify modules. As a consequence, uses of the macro
in non-modules will cause modprobe to misidentify their containing
object file as a module when it is not (false positives), and modprobe
might succeed rather than failing with a suitable error message.
So remove it in the files in this commit, none of which can be built as
modules.
Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: linux-modules@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Hitomi Hasegawa <hasegawa-hitomi@fujitsu.com>
Cc: Georgi Djakov <djakov@kernel.org>
Cc: linux-pm@vger.kernel.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Currently NOC_QOS_MODE_FIXED is defined as 0x0 which makes it the
default option (partial struct initialization). The default option
however should be NOC_QOS_MODE_INVALID.
That results in bogus QoS configurations being sent for port 0 (which
is used for the DRAM endpoint on BIMC, for example) coming from all nodes
with .qos.ap_owned = true and uninitialized .qos.qos_mode. It's also an
issue for newer SoCs where all nodes are treated as if they were ap_owned,
but not all of them have QoS configuration.
The NOC_QOS_MODEs are defined as preprocessor constants and are not used
anywhere outside qcom_icc_set_noc_qos(), which is easily worked around.
Separate the desc->type values from the values sent to msmbus in the
aforementioned function. Make the former an enum for better mainainability.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20230228-topic-qos-v7-1-815606092fff@linaro.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
It is preferred to use typed property access functions (i.e.
of_property_read_<type> functions) rather than low-level
of_get_property/of_find_property functions for reading properties. As
part of this, convert of_get_property/of_find_property calls to the
recently added of_property_present() helper when we just want to test
for presence of a property and nothing more.
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230310144709.1542841-1-robh@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
The current interconnect provider registration interface is inherently
racy as nodes are not added until the after adding the provider. This
can specifically cause racing DT lookups to trigger a NULL-pointer
deference when either a NULL pointer or not fully initialised node is
returned from exynos_generic_icc_xlate().
Switch to using the new API where the provider is not registered until
after it has been fully initialised.
Fixes: 2f95b9d5cf ("interconnect: Add generic interconnect driver for Exynos SoCs")
Cc: stable@vger.kernel.org # 5.11
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20230306075651.2449-16-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
The current interconnect provider registration interface is inherently
racy as nodes are not added until the after adding the provider. This
can specifically cause racing DT lookups to fail:
of_icc_xlate_onecell: invalid index 0
cpu cpu0: error -EINVAL: error finding src node
cpu cpu0: dev_pm_opp_of_find_icc_paths: Unable to get path0: -22
qcom-cpufreq-hw: probe of 18591000.cpufreq failed with error -22
Switch to using the new API where the provider is not registered until
after it has been fully initialised.
Fixes: 5bc9900add ("interconnect: qcom: Add OSM L3 interconnect provider support")
Cc: stable@vger.kernel.org # 5.7
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20230306075651.2449-6-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
The current interconnect provider interface is inherently racy as
providers are expected to be added before being fully initialised.
Specifically, nodes are currently not added and the provider data is not
initialised until after registering the provider which can cause racing
DT lookups to fail.
Add a new provider API which will be used to fix up the interconnect
drivers.
The old API is reimplemented using the new interface and will be removed
once all drivers have been fixed.
Fixes: 11f1ceca70 ("interconnect: Add generic on-chip interconnect API")
Fixes: 87e3031b6f ("interconnect: Allow endpoints translation via DT")
Cc: stable@vger.kernel.org # 5.1
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # i.MX8MP MSC SM2-MB-EP1 Board
Link: https://lore.kernel.org/r/20230306075651.2449-4-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
The interconnect framework currently expects that providers are only
removed when there are no users and after all nodes have been removed.
There is currently nothing that guarantees this to be the case and the
framework does not do any reference counting, but refusing to remove the
provider is never correct as that would leave a dangling pointer to a
resource that is about to be released in the global provider list (e.g.
accessible through debugfs).
Replace the current sanity checks with WARN_ON() so that the provider is
always removed.
Fixes: 11f1ceca70 ("interconnect: Add generic on-chip interconnect API")
Cc: stable@vger.kernel.org # 5.1: 680f8666ba: interconnect: Make icc_provider_del() return void
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # i.MX8MP MSC SM2-MB-EP1 Board
Link: https://lore.kernel.org/r/20230306075651.2449-3-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Konrad Dybcio
Neil Armstrong
Mike Tipton
Georgi Djakov
Dmitry Baryshkov
Johan Hovold
Dan Carpenter
Linus Torvalds
Nick Alcock
Rob Herring
Vivek Aknurwar
Jean Delvare