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path: root/drivers/clk/clk.c
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2022-09-15clk: Introduce clk_core_has_parent()Maxime Ripard
We will need to know if a clk_core pointer has a given parent in other functions, so let's create a clk_core_has_parent() function that clk_has_parent() will call into. For good measure, let's add some unit tests as well to make sure it works properly. Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-20-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> [sboyd@kernel.org: Move tmp declaration, fix conditional to check for current parent] Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-09-15clk: Switch from __clk_determine_rate to clk_core_round_rate_nolockMaxime Ripard
clk_mux_determine_rate_flags() will call into __clk_determine_rate() with a clk_hw pointer, while it has access to the clk_core pointer already. This leads to back and forth between clk_hw and clk_core, while __clk_determine_rate will only call clk_core_round_rate_nolock() with the clk_core pointer it retrieved from the clk_hw. Let's simplify things a bit by calling into clk_core_round_rate_nolock directly. Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-19-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-09-15clk: Add our request boundaries in clk_core_init_rate_reqMaxime Ripard
The expectation is that a new clk_rate_request is initialized through a call to clk_core_init_rate_req(). However, at the moment it only fills the parent rate and clk_hw pointer, but omits the other fields such as the clock rate boundaries. Some users of that function will update them after calling it, but most don't. As we are passed the clk_core pointer, we have access to those boundaries in clk_core_init_rate_req() however, so let's just fill it there and remove it from the few callers that do it right. Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-18-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-09-15clk: Introduce clk_hw_init_rate_request()Maxime Ripard
clk-divider instantiates clk_rate_request internally for its round_rate implementations to share the code with its determine_rate implementations. However, it's missing a few fields (min_rate, max_rate) that would be initialized properly if it was using clk_core_init_rate_req(). Let's create the clk_hw_init_rate_request() function for clock providers to be able to share the code to instation clk_rate_requests with the framework. This will also be useful for some tests introduced in later patches. Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-17-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-09-15clk: Move clk_core_init_rate_req() from clk_core_round_rate_nolock() to its ↵Maxime Ripard
caller The clk_rate_request structure is used internally as an argument for the clk_core_determine_round_nolock() and clk_core_round_rate_nolock(). In both cases, the clk_core_init_rate_req() function is used to initialize the clk_rate_request structure. However, the expectation on who gets to call that function is inconsistent between those two functions. Indeed, clk_core_determine_round_nolock() will assume the structure is properly initialized and will just use it. On the other hand, clk_core_round_rate_nolock() will call clk_core_init_rate_req() itself, expecting the caller to have filled only a minimal set of parameters (rate, min_rate and max_rate). If we ignore the calling convention inconsistency, this leads to a second inconsistency for drivers: * If they get called by the framework through clk_core_round_rate_nolock(), the rate, min_rate and max_rate fields will be filled by the caller, and the best_parent_rate and best_parent_hw fields will get filled by clk_core_init_rate_req(). * If they get called by a driver through __clk_determine_rate (and thus clk_core_round_rate_nolock), only best_parent_rate and best_parent_hw are being explicitly set by the framework. Even though we can reasonably expect rate to be set, only one of the 6 in-tree users explicitly set min_rate and max_rate. * If they get called by the framework through clk_core_determine_round_nolock(), then we have two callpaths. Either it will be called by clk_core_round_rate_nolock() itself, or it will be called by clk_calc_new_rates(), which will properly initialize rate, min_rate, max_rate itself, and best_parent_rate and best_parent_hw through clk_core_init_rate_req(). Even though the first and third case seems equivalent, they aren't when the clock has CLK_SET_RATE_PARENT. Indeed, in such a case clk_core_round_rate_nolock() will call itself on the current parent clock with the same clk_rate_request structure. The clk_core_init_rate_req() function will then be called on the parent clock, with the child clk_rate_request pointer and will fill the best_parent_rate and best_parent_hw fields with the parent context. When the whole recursion stops and the call returns, the initial caller will end up with a clk_rate_request structure with some information of the child clock (rate, min_rate, max_rate) and some others of the last clock up the tree whose child had CLK_SET_RATE_PARENT (best_parent_hw, best_parent_rate). In the most common case, best_parent_rate is going to be equal on all the parent clocks so it's not a big deal. However, best_parent_hw is going to point to a clock that never has been a valid parent for that clock which is definitely confusing. In order to fix the calling inconsistency, let's move the clk_core_init_rate_req() calls to the callers, which will also help a bit with the clk_core_round_rate_nolock() recursion. Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-16-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-09-15clk: Change clk_core_init_rate_req prototypeMaxime Ripard
The expectation is that a clk_rate_request structure is supposed to be initialized using clk_core_init_rate_req(), yet the rate we want to request still needs to be set by hand. Let's just pass the rate as a function argument so that callers don't have any extra work to do. Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-15-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-09-15clk: Set req_rate on reparentingMaxime Ripard
If a non-rate clock started by default with a parent that never registered, core->req_rate will be 0. The expectation is that whenever the parent will be registered, req_rate will be updated with the new value that has just been computed. However, if that clock is a mux, clk_set_parent() can also make that clock no longer orphan. In this case however, we never update req_rate. The natural solution to this would be to update core->rate and core->req_rate in clk_reparent() by calling clk_recalc(). However, this doesn't work in all cases. Indeed, clk_recalc() is called by __clk_set_parent_before(), __clk_set_parent() and clk_core_reparent(). Both __clk_set_parent_before() and __clk_set_parent will call clk_recalc() with the enable_lock taken through a call to clk_enable_lock(), the underlying locking primitive being a spinlock. clk_recalc() calls the backing driver .recalc_rate hook, and that implementation might sleep if the underlying device uses a bus with accesses that might sleep, such as i2c. In such a situation, we would end up sleeping while holding a spinlock, and thus in an atomic section. In order to work around this, we can move the core->rate and core->req_rate update to the clk_recalc() calling sites, after the enable_lock has been released if it was taken. The only situation that could still be problematic is the clk_core_reparent() -> clk_reparent() case that doesn't have any locking. clk_core_reparent() is itself called by clk_hw_reparent(), which is then called by 4 drivers: * clk-stm32mp1.c, stm32/clk-stm32-core.c and tegra/clk-tegra210-emc.c use it in their set_parent implementation. The set_parent hook is only called by __clk_set_parent() and clk_change_rate(), both of them calling it without the enable_lock taken. * clk/tegra/clk-tegra124-emc.c calls it as part of its set_rate implementation. set_rate is only called by clk_change_rate(), again without the enable_lock taken. In both cases we can't end up in a situation where the clk_hw_reparent() caller would hold a spinlock, so it seems like this is a good workaround. Let's also add some unit tests to make sure we cover the original bug. Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-14-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-09-15clk: Take into account uncached clocks in clk_set_rate_range()Maxime Ripard
clk_set_rate_range() will use the last requested rate for the clock when it calls into the driver set_rate hook. However, if CLK_GET_RATE_NOCACHE is set on that clock, the last requested rate might not be matching the current rate of the clock. In such a case, let's read out the rate from the hardware and use that in our set_rate instead. Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-13-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-09-15clk: Clarify clk_get_rate() expectationsMaxime Ripard
As shown by a number of clock users already, clk_get_rate() can be called whether or not the clock is enabled. Similarly, a number of clock drivers will return a rate of 0 whenever the rate cannot be figured out. Since it was a bit ambiguous before, let's make it clear in the clk_get_rate() documentation. Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-6-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-09-15clk: Skip clamping when rounding if there's no boundariesMaxime Ripard
Commit 948fb0969eae ("clk: Always clamp the rounded rate") recently started to clamp the request rate in the clk_rate_request passed as an argument of clk_core_determine_round_nolock() with the min_rate and max_rate fields of that same request. While the clk_rate_requests created by the framework itself always have those fields set, some drivers will create it themselves and don't always fill min_rate and max_rate. In such a case, we end up clamping the rate with a minimum and maximum of 0, thus always rounding the rate to 0. Let's skip the clamping if both min_rate and max_rate are set to 0 and complain so that it gets fixed. Fixes: 948fb0969eae ("clk: Always clamp the rounded rate") Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-4-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-09-15clk: Drop the rate range on clk_put()Maxime Ripard
When clk_put() is called we don't make another clk_set_rate() call to re-evaluate the rate boundaries. This is unlike clk_set_rate_range() that evaluates the rate again each time it is called. However, clk_put() is essentially equivalent to clk_set_rate_range() since after clk_put() completes the consumer's boundaries shouldn't be enforced anymore. Let's add a call to clk_set_rate_range() in clk_put() to make sure those rate boundaries are dropped and the clock provider drivers can react. In order to be as non-intrusive as possible, we'll just make that call if the clock had non-default boundaries. Also add a few tests to make sure this case is covered. Fixes: c80ac50cbb37 ("clk: Always set the rate on clk_set_range_rate") Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220816112530.1837489-3-maxime@cerno.tech Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-08-31Revert "clk: core: Honor CLK_OPS_PARENT_ENABLE for clk gate ops"Stephen Boyd
This reverts commit 35b0fac808b95eea1212f8860baf6ad25b88b087. Alexander reports that it causes boot failures on i.MX8M Plus based boards (specifically imx8mp-tqma8mpql-mba8mpxl.dts). Reported-by: Alexander Stein <alexander.stein@ew.tq-group.com> Cc: Chen-Yu Tsai <wenst@chromium.org> Fixes: 35b0fac808b9 ("clk: core: Honor CLK_OPS_PARENT_ENABLE for clk gate ops") Link: https://lore.kernel.org/r/12115951.O9o76ZdvQC@steina-w Signed-off-by: Stephen Boyd <sboyd@kernel.org> Link: https://lore.kernel.org/r/20220831175326.2523912-1-sboyd@kernel.org
2022-08-23clk: do not initialize retClaudiu Beznea
There is no need to initialize ret. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20220630151205.3935560-2-claudiu.beznea@microchip.com Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-08-23clk: remove extra empty lineClaudiu Beznea
Remove extra empty line. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20220630151205.3935560-1-claudiu.beznea@microchip.com Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-08-22clk: Fix comment typoJason Wang
The double `to' is duplicated in the comment, remove one. Signed-off-by: Jason Wang <wangborong@cdjrlc.com> Link: https://lore.kernel.org/r/20220811140030.28886-1-wangborong@cdjrlc.com Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-08-22clk: core: Fix runtime PM sequence in clk_core_unprepare()Chen-Yu Tsai
In the original commit 9a34b45397e5 ("clk: Add support for runtime PM"), the commit message mentioned that pm_runtime_put_sync() would be done at the end of clk_core_unprepare(). This mirrors the operations in clk_core_prepare() in the opposite order. However, the actual code that was added wasn't in the order the commit message described. Move clk_pm_runtime_put() to the end of clk_core_unprepare() so that it is in the correct order. Fixes: 9a34b45397e5 ("clk: Add support for runtime PM") Signed-off-by: Chen-Yu Tsai <wenst@chromium.org> Reviewed-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Link: https://lore.kernel.org/r/20220822081424.1310926-3-wenst@chromium.org Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-08-22clk: core: Honor CLK_OPS_PARENT_ENABLE for clk gate opsChen-Yu Tsai
In the previous commits that added CLK_OPS_PARENT_ENABLE, support for this flag was only added to rate change operations (rate setting and reparent) and disabling unused subtree. It was not added to the clock gate related operations. Any hardware driver that needs it for these operations will either see bogus results, or worse, hang. This has been seen on MT8192 and MT8195, where the imp_ii2_* clk drivers set this, but dumping debugfs clk_summary would cause it to hang. Fixes: fc8726a2c021 ("clk: core: support clocks which requires parents enable (part 2)") Fixes: a4b3518d146f ("clk: core: support clocks which requires parents enable (part 1)") Signed-off-by: Chen-Yu Tsai <wenst@chromium.org> Reviewed-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Link: https://lore.kernel.org/r/20220822081424.1310926-2-wenst@chromium.org Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-06-22clk: Remove never used devm_clk_*unregister()Andy Shevchenko
For the entire history of the devm_clk_*unregister() existence they were used only once (*) in 2015. Remove them. *) The commit 264e3b75de4e ("clk: s2mps11: Simplify s2mps11_clk_probe unwind paths") exactly supports the point of the change proposed here. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20220622171147.85603-1-andriy.shevchenko@linux.intel.com Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-04-22clk: using pm_runtime_resume_and_get instead of pm_runtime_get_syncMinghao Chi
Using pm_runtime_resume_and_get is more appropriate for simplifing code Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn> Link: https://lore.kernel.org/r/20220418110455.2559264-1-chi.minghao@zte.com.cn [sboyd@kernel.org: Drop local ret variable too] Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-04-02Revert "clk: Drop the rate range on clk_put()"Stephen Boyd
This reverts commit 7dabfa2bc4803eed83d6f22bd6f045495f40636b. There are multiple reports that this breaks boot on various systems. The common theme is that orphan clks are having rates set on them when that isn't expected. Let's revert it out for now so that -rc1 boots. Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Reported-by: Tony Lindgren <tony@atomide.com> Reported-by: Alexander Stein <alexander.stein@ew.tq-group.com> Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Link: https://lore.kernel.org/r/366a0232-bb4a-c357-6aa8-636e398e05eb@samsung.com Cc: Maxime Ripard <maxime@cerno.tech> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Link: https://lore.kernel.org/r/20220403022818.39572-1-sboyd@kernel.org
2022-03-29Merge branches 'clk-range', 'clk-uniphier', 'clk-apple' and 'clk-qcom' into ↵Stephen Boyd
clk-next - Make clk_set_rate_range() re-evaluate the limits each time - Introduce various clk_set_rate_range() tests - Add clk_drop_range() to drop a previously set range - Support for NCO blocks on Apple SoCs * clk-range: clk: Drop the rate range on clk_put() clk: test: Test clk_set_rate_range on orphan mux clk: Initialize orphan req_rate clk: bcm: rpi: Run some clocks at the minimum rate allowed clk: bcm: rpi: Set a default minimum rate clk: bcm: rpi: Add variant structure clk: Add clk_drop_range clk: Always set the rate on clk_set_range_rate clk: Use clamp instead of open-coding our own clk: Always clamp the rounded rate clk: Enforce that disjoints limits are invalid clk: Introduce Kunit Tests for the framework clk: Fix clk_hw_get_clk() when dev is NULL * clk-uniphier: clk: uniphier: Fix fixed-rate initialization * clk-apple: clk: clk-apple-nco: Allow and fix module building MAINTAINERS: Add clk-apple-nco under ARM/APPLE MACHINE clk: clk-apple-nco: Add driver for Apple NCO dt-bindings: clock: Add Apple NCO * clk-qcom: (61 commits) clk: qcom: gcc-msm8994: Fix gpll4 width dt-bindings: clock: fix dt_binding_check error for qcom,gcc-other.yaml clk: qcom: Add display clock controller driver for SM6125 dt-bindings: clock: add QCOM SM6125 display clock bindings clk: qcom: Fix sorting of SDX_GCC_65 in Makefile and Kconfig clk: qcom: gcc: Add emac GDSC support for SM8150 clk: qcom: gcc: sm8150: Fix some identation issues clk: qcom: gcc: Add UFS_CARD and UFS_PHY GDSCs for SM8150 clk: qcom: gcc: Add PCIe0 and PCIe1 GDSC for SM8150 clk: qcom: clk-rcg2: Update the frac table for pixel clock clk: qcom: clk-rcg2: Update logic to calculate D value for RCG clk: qcom: smd: Add missing MSM8998 RPM clocks clk: qcom: smd: Add missing RPM clocks for msm8992/4 dt-bindings: clock: qcom: rpmcc: Add RPM Modem SubSystem (MSS) clocks clk: qcom: gcc-ipq806x: add CryptoEngine resets dt-bindings: reset: add ipq8064 ce5 resets clk: qcom: gcc-ipq806x: add CryptoEngine clocks dt-bindings: clock: add ipq8064 ce5 clk define clk: qcom: gcc-ipq806x: add additional freq for sdc table clk: qcom: clk-rcg: add clk_rcg_floor_ops ops ...
2022-03-25clk: Drop the rate range on clk_put()Maxime Ripard
When clk_put() is called we don't make another clk_set_rate() call to re-evaluate the rate boundaries. This is unlike clk_set_rate_range() that evaluates the rate again each time it is called. However, clk_put() is essentially equivalent to clk_set_rate_range() since after clk_put() completes the consumer's boundaries shouldn't be enforced anymore. Let's add a call to clk_set_rate_range() in clk_put() to make sure those rate boundaries are dropped and the clock provider drivers can react. Also add a few tests to make sure this case is covered. Fixes: c80ac50cbb37 ("clk: Always set the rate on clk_set_range_rate") Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220325161144.1901695-4-maxime@cerno.tech [sboyd@kernel.org: Reword commit text] Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-03-25clk: Initialize orphan req_rateMaxime Ripard
When registering a clock that doesn't have a recalc_rate implementation, and doesn't have its parent registered yet, we initialize the clk_core rate and 'req_rate' fields to 0. The rate field is later updated when the parent is registered in clk_core_reparent_orphans_nolock() using __clk_recalc_rates(), but the 'req_rate' field is never updated. This leads to an issue in clk_set_rate_range() and clk_put(), since those functions will call clk_set_rate() with the content of 'req_rate' to provide drivers with the opportunity to change the rate based on the new boundaries. In this case, we would call clk_set_rate() with a rate of 0, effectively enforcing the minimum allowed for this clock whenever we would call one of those two functions, even though the actual rate might be within range. Let's fix this by setting 'req_rate' in clk_core_reparent_orphans_nolock() with the rate field content just updated by the call to __clk_recalc_rates(). Fixes: 1c8e600440c7 ("clk: Add rate constraints to clocks") Reported-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> # T30 Nexus7 Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220325161144.1901695-2-maxime@cerno.tech [sboyd@kernel.org: Reword comment] Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-03-11clk: Always set the rate on clk_set_range_rateMaxime Ripard
When we change a clock minimum or maximum using clk_set_rate_range(), clk_set_min_rate() or clk_set_max_rate(), the current code will only trigger a new rate change if the rate is outside of the new boundaries. However, a clock driver might want to always keep the clock rate to one of its boundary, for example the minimum to keep the power consumption as low as possible. Since they don't always get called though, clock providers don't have the opportunity to implement this behaviour. Let's trigger a clk_set_rate() on the previous requested rate every time clk_set_rate_range() is called. That way, providers that care about the new boundaries have a chance to adjust the rate, while providers that don't care about those new boundaries will return the same rate than before, which will be ignored by clk_set_rate() and won't result in a new rate change. Suggested-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220225143534.405820-7-maxime@cerno.tech Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-03-11clk: Use clamp instead of open-coding our ownMaxime Ripard
The code in clk_set_rate_range() will, if the current rate is outside of the new range, force it to the minimum or maximum. Since it's running under the condition that the rate is either lower than the minimum, or higher than the maximum, this is equivalent to using clamp, while being less readable. Let's switch to using clamp instead. Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220225143534.405820-6-maxime@cerno.tech Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-03-11clk: Always clamp the rounded rateMaxime Ripard
The current core while setting the min and max rate properly in the clk_request structure will not make sure that the requested rate is within these boundaries, leaving it to each and every driver to make sure it is. It's not clear if this was on purpose or not, but this introduces some inconsistencies within the API. For example, a user setting a range and then calling clk_round_rate() with a value outside of that range will get the same value back (ignoring any driver adjustements), effectively ignoring the range that was just set. Another one, arguably worse, is that it also makes clk_round_rate() and clk_set_rate() behave differently if there's a range and the rate being used for both is outside that range. As we have seen, the rate will be returned unchanged by clk_round_rate(), but clk_set_rate() will error out returning -EINVAL. Let's make sure the framework will always clamp the rate to the current range found on the clock, which will fix both these inconsistencies. Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220225143534.405820-5-maxime@cerno.tech Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-03-11clk: Enforce that disjoints limits are invalidMaxime Ripard
If we were to have two users of the same clock, doing something like: clk_set_rate_range(user1, 1000, 2000); clk_set_rate_range(user2, 3000, 4000); The second call would fail with -EINVAL, preventing from getting in a situation where we end up with impossible limits. However, this is never explicitly checked against and enforced, and works by relying on an undocumented behaviour of clk_set_rate(). Indeed, on the first clk_set_rate_range will make sure the current clock rate is within the new range, so it will be between 1000 and 2000Hz. On the second clk_set_rate_range(), it will consider (rightfully), that our current clock is outside of the 3000-4000Hz range, and will call clk_core_set_rate_nolock() to set it to 3000Hz. clk_core_set_rate_nolock() will then call clk_calc_new_rates() that will eventually check that our rate 3000Hz rate is outside the min 3000Hz max 2000Hz range, will bail out, the error will propagate and we'll eventually return -EINVAL. This solely relies on the fact that clk_calc_new_rates(), and in particular clk_core_determine_round_nolock(), won't modify the new rate allowing the error to be reported. That assumption won't be true for all drivers, and most importantly we'll break that assumption in a later patch. It can also be argued that we shouldn't even reach the point where we're calling clk_core_set_rate_nolock(). Let's make an explicit check for disjoints range before we're doing anything. Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220225143534.405820-4-maxime@cerno.tech Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-03-11clk: Fix clk_hw_get_clk() when dev is NULLMaxime Ripard
Any registered clk_core structure can have a NULL pointer in its dev field. While never actually documented, this is evidenced by the wide usage of clk_register and clk_hw_register with a NULL device pointer, and the fact that the core of_clk_hw_register() function also passes a NULL device pointer. A call to clk_hw_get_clk() on a clk_hw struct whose clk_core is in that case will result in a NULL pointer derefence when it calls dev_name() on that NULL device pointer. Add a test for this case and use NULL as the dev_id if the device pointer is NULL. Fixes: 30d6f8c15d2c ("clk: add api to get clk consumer from clk_hw") Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20220225143534.405820-2-maxime@cerno.tech Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2022-02-25clk: Mark clk_core_evict_parent_cache_subtree() 'target' constStephen Boyd
Clarify that the 'target' clk isn't being modified, instead it's being searched for. Mark it const so the function can't modify it. Signed-off-by: Stephen Boyd <sboyd@kernel.org> Link: https://lore.kernel.org/r/20220217220554.2711696-3-sboyd@kernel.org
2022-02-25clk: Mark 'all_lists' as constStephen Boyd
This list array doesn't change at runtime. Mark it const to move to RO memory. Signed-off-by: Stephen Boyd <sboyd@kernel.org> Link: https://lore.kernel.org/r/20220217220554.2711696-2-sboyd@kernel.org
2022-01-12Merge tag 'clk-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux Pull clk updates from Stephen Boyd: "We have a couple patches in the framework core this time around but they're mostly minor cleanups and some debugfs stuff. The real work that's in here is the typical pile of clk driver updates and new SoC support. Per usual (or maybe just recent trends), Qualcomm gains a handful of SoC drivers additions and has the largest diffstat. After that there are quite a few updates to the Allwinner (sunxi) drivers to support modular drivers and Renesas is heavily updated to add more support for various clks. Overall it looks pretty normal. New Drivers: - Add MDMA and BDMA clks to Ingenic JZ4760 and JZ4770 - MediaTek mt7986 SoC basic support - Clock and reset driver for Toshiba Visconti SoCs - Initial clock driver for the Exynos7885 SoC (Samsung Galaxy A8) - Allwinner D1 clks - Lan966x Generic Clock Controller driver and associated DT bindings - Qualcomm SDX65, SM8450, and MSM8976 GCC clks - Qualcomm SDX65 and SM8450 RPMh clks Updates: - Set suppress_bind_attrs to true for i.MX8ULP driver - Switch from do_div to div64_ul for throughout all i.MX drivers - Fix imx8mn_clko1_sels for i.MX8MN - Remove unused IPG_AUDIO_ROOT from i.MX8MP - Switch parent for audio_root_clk to audio ahb in i.MX8MP driver - Removal of all remaining uses of __clk_lookup() in drivers/clk/samsung - Refactoring of the CPU clocks registration to use common interface - An update of the Exynos850 driver (support for more clock domains) required by the E850-96 development board - Prep for runtime PM and generic power domains on Tegra - Support modular Allwinner clk drivers via platform bus - Lan966x clock driver extended to support clock gating - Add serial (SCI1), watchdog (WDT), timer (OSTM), SPI (RSPI), and thermal (TSU) clocks and resets on Renesas RZ/G2L - Rework SDHI clock handling in the Renesas R-Car Gen3 and RZ/G2 clock drivers, and in the Renesas SDHI driver - Make the Cortex-A55 (I) clock on Renesas RZ/G2L programmable - Document support for the new Renesas R-Car S4-8 (R8A779F0) SoC - Add support for the new Renesas R-Car S4-8 (R8A779F0) SoC - Add GPU clock and resets on Renesas RZ/G2L - Add clk-provider.h to various Qualcomm clk drivers - devm version of clk_hw_register_gate() - kerneldoc fixes in a couple drivers" * tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (131 commits) clk: visconti: Remove pointless NULL check in visconti_pll_add_lookup() clk: mediatek: add mt7986 clock support clk: mediatek: add mt7986 clock IDs dt-bindings: clock: mediatek: document clk bindings for mediatek mt7986 SoC clk: mediatek: clk-gate: Use regmap_{set/clear}_bits helpers clk: mediatek: clk-gate: Shrink by adding clockgating bit check helper clk: x86: Fix clk_gate_flags for RV_CLK_GATE clk: x86: Use dynamic con_id string during clk registration ACPI: APD: Add a fmw property clk-name drivers: acpi: acpi_apd: Remove unused device property "is-rv" x86: clk: clk-fch: Add support for newer family of AMD's SOC clk: ingenic: Add MDMA and BDMA clocks dt-bindings: clk/ingenic: Add MDMA and BDMA clocks clk: bm1880: remove kfrees on static allocations clk: Drop unused COMMON_CLK_STM32MP157_SCMI config clk: st: clkgen-mux: search reg within node or parent clk: st: clkgen-fsyn: search reg within node or parent clk: Enable/Disable runtime PM for clk_summary MAINTAINERS: Add entries for Toshiba Visconti PLL and clock controller clk: visconti: Add support common clock driver and reset driver ...
2022-01-11Merge branches 'clk-doc', 'clk-renesas', 'clk-at91', 'clk-cleanup' and ↵Stephen Boyd
'clk-debugfs' into clk-next * clk-doc: clk: Gemini: fix struct name in kernel-doc clk: zynq: pll: Fix kernel-doc warnings clk: imx: pllv1: fix kernel-doc notation for struct clk_pllv1 * clk-renesas: (31 commits) clk: renesas: r9a07g044: Add GPU clock and reset entries clk: renesas: r9a07g044: Add mux and divider for G clock clk: renesas: r9a07g044: Rename CLK_PLL3_DIV4 macro clk: renesas: cpg-mssr: Add support for R-Car S4-8 clk: renesas: rcar-gen4: Introduce R-Car Gen4 CPG driver dt-bindings: clock: Add r8a779f0 CPG Core Clock Definitions dt-bindings: power: Add r8a779f0 SYSC power domain definitions clk: renesas: r9a07g044: Add TSU clock and reset entry mmc: renesas_sdhi: Simplify an expression mmc: renesas_sdhi: Use devm_clk_get_optional() to obtain CD clock dt-bindings: clock: renesas,cpg-mssr: Document r8a779f0 clk: renesas: cpg-mssr: propagate return value of_genpd_add_provider_simple() clk: renesas: cpg-mssr: Check return value of pm_genpd_init() clk: renesas: rzg2l: propagate return value of_genpd_add_provider_simple() clk: renesas: rzg2l: Check return value of pm_genpd_init() clk: renesas: r9a07g044: Add RSPI clock and reset entries clk: renesas: r9a07g044: Change core clock "I" from DEF_FIXED->DEF_DIV clk: renesas: rzg2l: Add CPG_PL1_DDIV macro mmc: renesas_sdhi: Parse DT for SDnH mmc: renesas_sdhi: Use dev_err_probe when getting clock fails ... * clk-at91: clk: lan966x: Extend lan966x clock driver for clock gating support dt-bindings: clock: lan966x: Extend includes with clock gates dt-bindings: clock: lan966x: Extend for clock gate support clk: gate: Add devm_clk_hw_register_gate() clk: lan966x: Add lan966x SoC clock driver dt-bindings: clock: lan966x: Add LAN966X Clock Controller dt-bindings: clock: lan966x: Add binding includes for lan966x SoC clock IDs * clk-cleanup: clk: stm32mp1: remove redundant assignment to pointer data clk: __clk_core_init() never takes NULL clk: clk_core_get() can also return NULL clk/ti/adpll: Make const pointer error a static const array * clk-debugfs: clk: Enable/Disable runtime PM for clk_summary clk: Emit a stern warning with writable debugfs enabled clk: Add write operation for clk_parent debugfs node
2022-01-05clk: Enable/Disable runtime PM for clk_summaryTaniya Das
The registers for some clocks in the SOC area, which are under the power domain are required to be enabled before accessing them. During the clk_summary if the power-domains are not enabled they could result into NoC errors. Thus ensure the register access of the clock controller is done with pm_untime_get/put functions. Signed-off-by: Taniya Das <tdas@codeaurora.org> Link: https://lore.kernel.org/r/1640018638-19436-3-git-send-email-tdas@codeaurora.org Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-12-10clk: Emit a stern warning with writable debugfs enabledStephen Boyd
We don't want vendors to be enabling this part of the clk code and shipping it to customers. Exposing the ability to change clk frequencies and parents via debugfs is potentially damaging to the system if folks don't know what they're doing. Emit a strong warning so that the message is clear: don't enable this outside of development systems. Fixes: 37215da5553e ("clk: Add support for setting clk_rate via debugfs") Cc: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20211210014237.2130300-1-sboyd@kernel.org Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-12-09clk: Add write operation for clk_parent debugfs nodeSam Protsenko
Useful for testing mux clocks. One can write the index of the parent to be set into clk_parent node, starting from 0. Example # cd /sys/kernel/debug/clk/mout_peri_bus # cat clk_possible_parents dout_shared0_div4 dout_shared1_div4 # cat clk_parent dout_shared0_div4 # echo 1 > clk_parent # cat clk_parent dout_shared1_div4 CLOCK_ALLOW_WRITE_DEBUGFS has to be defined in drivers/clk/clk.c in order to use this feature. Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Fabio Estevam <festevam@gmail.com> Acked-by: Michael Turquette <mturquette@baylibre.com> Link: https://lore.kernel.org/r/20211013172042.10884-1-semen.protsenko@linaro.org [sboyd@kernel.org: Collapse ifdefs] Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-12-09clk: __clk_core_init() never takes NULLStephen Boyd
The only caller of __clk_core_init() allocates the pointer and checks the allocation for NULL so this check is impossible. Remove it. Signed-off-by: Stephen Boyd <sboyd@kernel.org> Link: https://lore.kernel.org/r/20211208041534.3928718-2-sboyd@kernel.org
2021-12-09clk: clk_core_get() can also return NULLStephen Boyd
Nothing stops a clk controller from registering an OF clk provider before registering those clks with the clk framework. This is not great but we deal with it in the clk framework by refusing to hand out struct clk pointers when 'hw->core' is NULL, the indication that clk_register() has been called. Within clk_core_fill_parent_index() we considered this case when a clk_hw pointer is referenced directly by filling in the parent cache with an -EPROBE_DEFER pointer when the core pointer is NULL. When we lookup a parent with clk_core_get() we don't care about the return value being NULL though, because that was considered largely impossible, but it's been proven now that it can be NULL if two clk providers are probing in parallel and the parent provider has been registered before the clk has. Let's check for NULL here as well and treat it the same as direct clk_hw references. Signed-off-by: Stephen Boyd <sboyd@kernel.org> Link: https://lore.kernel.org/r/20211208041534.3928718-1-sboyd@kernel.org
2021-12-07clk: Don't parent clks until the parent is fully registeredMike Tipton
Before commit fc0c209c147f ("clk: Allow parents to be specified without string names") child clks couldn't find their parent until the parent clk was added to a list in __clk_core_init(). After that commit, child clks can reference their parent clks directly via a clk_hw pointer, or they can lookup that clk_hw pointer via DT if the parent clk is registered with an OF clk provider. The common clk framework treats hw->core being non-NULL as "the clk is registered" per the logic within clk_core_fill_parent_index(): parent = entry->hw->core; /* * We have a direct reference but it isn't registered yet? * Orphan it and let clk_reparent() update the orphan status * when the parent is registered. */ if (!parent) Therefore we need to be extra careful to not set hw->core until the clk is fully registered with the clk framework. Otherwise we can get into a situation where a child finds a parent clk and we move the child clk off the orphan list when the parent isn't actually registered, wrecking our enable accounting and breaking critical clks. Consider the following scenario: CPU0 CPU1 ---- ---- struct clk_hw clkBad; struct clk_hw clkA; clkA.init.parent_hws = { &clkBad }; clk_hw_register(&clkA) clk_hw_register(&clkBad) ... __clk_register() hw->core = core ... __clk_register() __clk_core_init() clk_prepare_lock() __clk_init_parent() clk_core_get_parent_by_index() clk_core_fill_parent_index() if (entry->hw) { parent = entry->hw->core; At this point, 'parent' points to clkBad even though clkBad hasn't been fully registered yet. Ouch! A similar problem can happen if a clk controller registers orphan clks that are referenced in the DT node of another clk controller. Let's fix all this by only setting the hw->core pointer underneath the clk prepare lock in __clk_core_init(). This way we know that clk_core_fill_parent_index() can't see hw->core be non-NULL until the clk is fully registered. Fixes: fc0c209c147f ("clk: Allow parents to be specified without string names") Signed-off-by: Mike Tipton <quic_mdtipton@quicinc.com> Link: https://lore.kernel.org/r/20211109043438.4639-1-quic_mdtipton@quicinc.com [sboyd@kernel.org: Reword commit text, update comment] Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-10-26clk: use clk_core_get_rate_recalc() in clk_rate_get()Claudiu Beznea
In case clock flags contains CLK_GET_RATE_NOCACHE the clk_rate_get() will return the cached rate. Thus, use clk_core_get_rate_recalc() which takes proper action when clock flags contains CLK_GET_RATE_NOCACHE. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Link: https://lore.kernel.org/r/20211011112719.3951784-16-claudiu.beznea@microchip.com Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> [sboyd@kernel.org: Grab prepare lock around operation] Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-05-11clk: Skip clk provider registration when np is NULLTudor Ambarus
commit 6579c8d97ad7 ("clk: Mark fwnodes when their clock provider is added") revealed that clk/bcm/clk-raspberrypi.c driver calls devm_of_clk_add_hw_provider(), with a NULL dev->of_node, which resulted in a NULL pointer dereference in of_clk_add_hw_provider() when calling fwnode_dev_initialized(). Returning 0 is reducing the if conditions in driver code and is being consistent with the CONFIG_OF=n inline stub that returns 0 when CONFIG_OF is disabled. The downside is that drivers will maybe register clkdev lookups when they don't need to and waste some memory. Fixes: 6579c8d97ad7 ("clk: Mark fwnodes when their clock provider is added") Fixes: 3c9ea42802a1 ("clk: Mark fwnodes when their clock provider is added/removed") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Reviewed-by: Saravana Kannan <saravanak@google.com> Reviewed-by: Nicolas Saenz Julienne <nsaenz@kernel.org> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Link: https://lore.kernel.org/r/20210426065618.588144-1-tudor.ambarus@microchip.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-28Merge tag 'clk-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux Pull clk updates from Stephen Boyd: "Here's a collection of largely clk driver updates. The usual suspects are here: i.MX, Qualcomm, Renesas, Allwinner, Samsung, and Rockchip, but it feels pretty light on commits. There's only one real commit to the framework core and that's to consolidate code. Otherwise the diffstat is dominated by many Qualcomm clk driver patches that modernize the driver for the proper way of speciying clk parents. That's shifting data around, which could subtly break things so I'll be on the lookout for fixes. New Drivers: - Proper clk driver for Mediatek MT7621 SoCs - Support for the clock controller on the new Rockchip rk3568 Updates: - Simplify Zynq Kconfig dependencies - Use clk_hw pointers in socfpga driver - Cleanup parent data in qcom clk drivers - Some cleanups for rk3399 modularization - Fix reparenting of i.MX UART clocks by initializing only the ones associated to stdout - Correct the PCIE clocks for i.MX8MP and i.MX8MQ - Make i.MX LPCG and SCU clocks return on registering failure - Kernel doc fixes - Add DAB hardware accelerator clocks on Renesas R-Car E3 and M3-N - Add timer (TMU) clocks on Renesas R-Car H3 ES1.0 - Add Timer (TMU & CMT) and thermal sensor (TSC) clocks on Renesas R-Car V3U - Sigma-delta modulation on Allwinner V3s audio PLL" * tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (82 commits) MAINTAINERS: add MT7621 CLOCK maintainer staging: mt7621-dts: use valid vendor 'mediatek' instead of invalid 'mtk' staging: mt7621-dts: make use of new 'mt7621-clk' clk: ralink: add clock driver for mt7621 SoC clk: uniphier: Fix potential infinite loop clk: qcom: rpmh: add support for SDX55 rpmh IPA clock clk: qcom: gcc-sdm845: get rid of the test clock clk: qcom: convert SDM845 Global Clock Controller to parent_data dt-bindings: clock: separate SDM845 GCC clock bindings clk: qcom: apss-ipq-pll: Add missing MODULE_DEVICE_TABLE clk: qcom: a53-pll: Add missing MODULE_DEVICE_TABLE clk: qcom: a7-pll: Add missing MODULE_DEVICE_TABLE dt: bindings: add mt7621-sysc device tree binding documentation dt-bindings: clock: add dt binding header for mt7621 clocks clk: samsung: Remove redundant dev_err calls clk: zynqmp: pll: add set_pll_mode to check condition in zynqmp_pll_enable clk: zynqmp: move zynqmp_pll_set_mode out of round_rate callback clk: zynqmp: Drop dependency on ARCH_ZYNQMP clk: zynqmp: Enable the driver if ZYNQMP_FIRMWARE is selected clk: qcom: gcc-sm8350: use ARRAY_SIZE instead of specifying num_parents ...
2021-04-14Merge tag 'v5.12-rc7' into driver-core-nextGreg Kroah-Hartman
We need the driver core fix in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-02clk: fix invalid usage of list cursor in unregisterLukasz Bartosik
Fix invalid usage of a list_for_each_entry cursor in clk_notifier_unregister(). When list is empty or if the list is completely traversed (without breaking from the loop on one of the entries) then the list cursor does not point to a valid entry and therefore should not be used. The patch fixes a logical bug that hasn't been seen in pratice however it is analogus to the bug fixed in clk_notifier_register(). The issue was dicovered when running 5.12-rc1 kernel on x86_64 with KASAN enabled: BUG: KASAN: global-out-of-bounds in clk_notifier_register+0xab/0x230 Read of size 8 at addr ffffffffa0d10588 by task swapper/0/1 CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.12.0-rc1 #1 Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.430.0 07/20/2018 Call Trace: dump_stack+0xee/0x15c print_address_description+0x1e/0x2dc kasan_report+0x188/0x1ce ? clk_notifier_register+0xab/0x230 ? clk_prepare_lock+0x15/0x7b ? clk_notifier_register+0xab/0x230 clk_notifier_register+0xab/0x230 dw8250_probe+0xc01/0x10d4 ... Memory state around the buggy address: ffffffffa0d10480: 00 00 00 00 00 03 f9 f9 f9 f9 f9 f9 00 00 00 00 ffffffffa0d10500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f9 f9 >ffffffffa0d10580: f9 f9 f9 f9 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffffffffa0d10600: 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9 00 00 00 00 ffffffffa0d10680: 00 00 00 00 00 00 00 00 f9 f9 f9 f9 00 00 00 00 ================================================================== Fixes: b2476490ef11 ("clk: introduce the common clock framework") Reported-by: Lukasz Majczak <lma@semihalf.com> Signed-off-by: Lukasz Bartosik <lb@semihalf.com> Link: https://lore.kernel.org/r/20210401225149.18826-2-lb@semihalf.com Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-04-02clk: fix invalid usage of list cursor in registerLukasz Bartosik
Fix invalid usage of a list_for_each_entry cursor in clk_notifier_register(). When list is empty or if the list is completely traversed (without breaking from the loop on one of the entries) then the list cursor does not point to a valid entry and therefore should not be used. The issue was dicovered when running 5.12-rc1 kernel on x86_64 with KASAN enabled: BUG: KASAN: global-out-of-bounds in clk_notifier_register+0xab/0x230 Read of size 8 at addr ffffffffa0d10588 by task swapper/0/1 CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.12.0-rc1 #1 Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.430.0 07/20/2018 Call Trace: dump_stack+0xee/0x15c print_address_description+0x1e/0x2dc kasan_report+0x188/0x1ce ? clk_notifier_register+0xab/0x230 ? clk_prepare_lock+0x15/0x7b ? clk_notifier_register+0xab/0x230 clk_notifier_register+0xab/0x230 dw8250_probe+0xc01/0x10d4 ... Memory state around the buggy address: ffffffffa0d10480: 00 00 00 00 00 03 f9 f9 f9 f9 f9 f9 00 00 00 00 ffffffffa0d10500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f9 f9 >ffffffffa0d10580: f9 f9 f9 f9 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffffffffa0d10600: 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9 00 00 00 00 ffffffffa0d10680: 00 00 00 00 00 00 00 00 f9 f9 f9 f9 00 00 00 00 ================================================================== Fixes: b2476490ef11 ("clk: introduce the common clock framework") Reported-by: Lukasz Majczak <lma@semihalf.com> Signed-off-by: Lukasz Bartosik <lb@semihalf.com> Link: https://lore.kernel.org/r/20210401225149.18826-1-lb@semihalf.com Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-03-26clk: Drop double "if" in clk_core_determine_round_nolock() commentGeert Uytterhoeven
The comments for clk_core_determine_round_nolock() contain a double "if": one at the end of a line, followed by another one at the beginning of the next line. Drop the former. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20210326120833.1578153-1-geert+renesas@glider.be Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-03-23clk: Mark fwnodes when their clock provider is addedTudor Ambarus
This is a follow-up for: commit 3c9ea42802a1 ("clk: Mark fwnodes when their clock provider is added/removed") The above commit updated the deprecated of_clk_add_provider(), but missed to update the preferred of_clk_add_hw_provider(). Update it now. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by: Stephen Boyd <sboyd@kernel.org> Reviewed-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210210114435.122242-2-tudor.ambarus@microchip.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-13clk: use clk_core_enable_lock() a bit moreRasmus Villemoes
Use clk_core_enable_lock() and clk_core_disable_lock() in a few places rather than open-coding them. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20210305003334.575831-1-linux@rasmusvillemoes.dk Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2021-02-24Merge tag 'driver-core-5.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core / debugfs update from Greg KH: "Here is the "big" driver core and debugfs update for 5.12-rc1 This set of driver core patches caused a bunch of problems in linux-next for the past few weeks, when Saravana tried to set fw_devlink=on as the default functionality. This caused a number of systems to stop booting, and lots of bugs were fixed in this area for almost all of the reported systems, but this option is not ready to be turned on just yet for the default operation based on this testing, so I've reverted that change at the very end so we don't have to worry about regressions in 5.12 We will try to turn this on for 5.13 if testing goes better over the next few months. Other than the fixes caused by the fw_devlink testing in here, there's not much more: - debugfs fixes for invalid input into debugfs_lookup() - kerneldoc cleanups - warn message if platform drivers return an error on their remove callback (a futile effort, but good to catch). All of these have been in linux-next for a while now, and the regressions have gone away with the revert of the fw_devlink change" * tag 'driver-core-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (35 commits) Revert "driver core: Set fw_devlink=on by default" of: property: fw_devlink: Ignore interrupts property for some configs debugfs: do not attempt to create a new file before the filesystem is initalized debugfs: be more robust at handling improper input in debugfs_lookup() driver core: auxiliary bus: Fix calling stage for auxiliary bus init of: irq: Fix the return value for of_irq_parse_one() stub of: irq: make a stub for of_irq_parse_one() clk: Mark fwnodes when their clock provider is added/removed PM: domains: Mark fwnodes when their powerdomain is added/removed irqdomain: Mark fwnodes when their irqdomain is added/removed driver core: fw_devlink: Handle suppliers that don't use driver core of: property: Add fw_devlink support for optional properties driver core: Add fw_devlink.strict kernel param of: property: Don't add links to absent suppliers driver core: fw_devlink: Detect supplier devices that will never be added driver core: platform: Emit a warning if a remove callback returned non-zero of: property: Fix fw_devlink handling of interrupts/interrupts-extended gpiolib: Don't probe gpio_device if it's not the primary device device.h: Remove bogus "the" in kerneldoc gpiolib: Bind gpio_device to a driver to enable fw_devlink=on by default ...
2021-02-09clk: Mark fwnodes when their clock provider is added/removedSaravana Kannan
This allows fw_devlink to recognize clock provider drivers that don't use the device-driver model to initialize the device. fw_devlink will use this information to make sure consumers of such clock providers aren't indefinitely blocked from probing, waiting for the power domain device to appear and bind to a driver. Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210205222644.2357303-9-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27PM: clk: make PM clock layer compatible with clocks that must sleepNicolas Pitre
The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>