For all cpuidle drivers that use CPUIDLE_FLAG_RCU_IDLE, ensure that
all functions that call ct_cpuidle_enter() are marked __cpuidle.
( due to lack of noinstr validation on these platforms it is entirely
possible this isn't complete )
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230112195542.274096325@infradead.org
The whole disable-RCU, enable-IRQS dance is very intricate since
changing IRQ state is traced, which depends on RCU.
Add two helpers for the cpuidle case that mirror the entry code:
ct_cpuidle_enter()
ct_cpuidle_exit()
And fix all the cases where the enter/exit dance was buggy.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195540.130014793@infradead.org
Doing RCU-idle outside the driver, only to then temporarily enable it
again, at least twice, before going idle is suboptimal.
Notably once implicitly through the cpu_pm_*() calls and once
explicitly doing RCU_NONIDLE().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20230112195539.699546331@infradead.org
Check whether PMC is ready before proceeding with the cpuidle registration.
This fixes racing with the PMC driver probe order, which results in a
disabled deepest CC6 idling state if cpuidle driver is probed before the
PMC.
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The do_idle firmware call is unused by all Tegra SoCs, hence remove it in
order to keep driver's code clean.
Tested-by: Anton Bambura <jenneron@protonmail.com> # TF701 T114
Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya T30
Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya T30
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210302095405.28453-2-digetx@gmail.com
Trusted Foundation firmware doesn't implement the do_idle call and in
this case suspending should fall back to the common suspend path. In order
to fix this issue we will unconditionally set the NOFLUSH_L2 mode via
firmware call, which is a NO-OP on Tegra30/124, and then proceed to the
C7 idling, like it was done by the older Tegra114 cpuidle driver.
Fixes: 14e086baca ("cpuidle: tegra: Squash Tegra114 driver into the common driver")
Cc: stable@vger.kernel.org # 5.7+
Reported-by: Anton Bambura <jenneron@protonmail.com> # TF701 T114
Tested-by: Anton Bambura <jenneron@protonmail.com> # TF701 T114
Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya T30
Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya T30
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210302095405.28453-1-digetx@gmail.com
Annotate tegra_pm_set[clear]_cpu_in_lp2() with RCU_NONIDLE in order to
fix lockdep warning about suspicious RCU usage of a spinlock during late
idling phase.
WARNING: suspicious RCU usage
...
include/trace/events/lock.h:13 suspicious rcu_dereference_check() usage!
...
(dump_stack) from (lock_acquire)
(lock_acquire) from (_raw_spin_lock)
(_raw_spin_lock) from (tegra_pm_set_cpu_in_lp2)
(tegra_pm_set_cpu_in_lp2) from (tegra_cpuidle_enter)
(tegra_cpuidle_enter) from (cpuidle_enter_state)
(cpuidle_enter_state) from (cpuidle_enter_state_coupled)
(cpuidle_enter_state_coupled) from (cpuidle_enter)
(cpuidle_enter) from (do_idle)
...
Tested-by: Peter Geis <pgwipeout@gmail.com>
Reported-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The enter() callback of CPUIDLE drivers returns index of the entered idle
state on success or a negative value on failure. The negative value could
any negative value, i.e. it doesn't necessarily needs to be a error code.
That's because CPUIDLE core only cares about the fact of failure and not
about the reason of the enter() failure.
Like every other enter() callback, the arm_cpuidle_simple_enter() returns
the entered idle-index on success. Unlike some of other drivers, it never
fails. It happened that TEGRA_C1=index=err=0 in the code of cpuidle-tegra
driver, and thus, there is no problem for the cpuidle-tegra driver created
by the typo in the code which assumes that the arm_cpuidle_simple_enter()
returns a error code.
The arm_cpuidle_simple_enter() also may return a -ENODEV error if CPU_IDLE
is disabled in a kernel's config, but all CPUIDLE drivers are disabled if
CPU_IDLE is disabled, including the cpuidle-tegra driver. So we can't ever
see the error code from arm_cpuidle_simple_enter() today.
Of course the code may get some changes in the future and then the
typo may transform into a real bug, so let's correct the typo! The
tegra_cpuidle_state_enter() is now changed to make it return the entered
idle-index on success and negative error code on fail, which puts it on
par with the arm_cpuidle_simple_enter(), making code consistent in regards
to the error handling.
This patch fixes a minor typo in the code, it doesn't fix any bugs.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Control Flow Integrity(CFI) is a security mechanism that disallows
changes to the original control flow graph of a compiled binary,
making it significantly harder to perform such attacks.
init_state_node() assign same function callback to different
function pointer declarations.
static int init_state_node(struct cpuidle_state *idle_state,
const struct of_device_id *matches,
struct device_node *state_node) { ...
idle_state->enter = match_id->data; ...
idle_state->enter_s2idle = match_id->data; }
Function declarations:
struct cpuidle_state { ...
int (*enter) (struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index);
void (*enter_s2idle) (struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index); };
In this case, either enter() or enter_s2idle() would cause CFI check
failed since they use same callee.
Align function prototype of enter() since it needs return value for
some use cases. The return value of enter_s2idle() is no
need currently.
Signed-off-by: Neal Liu <neal.liu@mediatek.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The new Tegra CPU Idle driver now has a unified code path for the coupled
CC6 (LP2) state, this allows to enable the deepest idling state on Tegra30
SoC where the whole CPU cluster is power-gated.
Tested-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Tested-by: Jasper Korten <jja2000@gmail.com>
Tested-by: David Heidelberg <david@ixit.cz>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
LP2 suspending could be unavailable, for example if it is disabled in a
device-tree. CC6 cpuidle state won't work in that case.
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Tegra20/30/114/124 SoCs have common idling states, thus there is no much
point in having separate drivers for a similar hardware. This patch moves
Tegra114/124 arch/ drivers into the common driver without any functional
changes. The CC6 state is kept disabled on Tegra114/124 because the core
Tegra PM code needs some more work in order to support that state.
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Tegra20 and Terga30 SoCs have common C1 and CC6 idling states and thus
share the same code paths, there is no point in having separate drivers
for a similar hardware. This patch merely moves functionality of the old
driver into the new, although the CC6 state is kept disabled for now since
old driver had a rudimentary support for this state (allowing to enter
into CC6 only when secondary CPUs are put offline), while new driver can
provide a full-featured support. The new feature will be enabled by
another patch.
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Jasper Korten <jja2000@gmail.com>
Tested-by: David Heidelberg <david@ixit.cz>
Tested-by: Nicolas Chauvet <kwizart@gmail.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The driver's code is refactored in a way that will make it easy to
support Tegra30/114/124 SoCs by this unified driver later on. The
current functionality is equal to the old Tegra20 driver, only the
code's structure changed a tad. This is also a proper platform driver
now.
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
