OPP bindings (for few properties) allow a platform to choose a
value/range among a set of available options. The options are present as
opp-<prop>-<name>, where the platform needs to supply the <name> string.
The OPP properties which allow such an option are: opp-microvolt and
opp-microamp.
Add support to the OPP-core to parse these bindings, by introducing
dev_pm_opp_{set|put}_prop_name() APIs.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
OPP bindings allow a platform to enable OPPs based on the version of the
hardware they are used for.
Add support to the OPP-core to parse these bindings, by introducing
dev_pm_opp_{set|put}_supported_hw() APIs.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Few doc-style comments were missing, add them. Rearrange another one to
match the sequence within the structure.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch adds debugfs support to OPP layer to export OPPs and their
properties for all the devices.
This creates a top level directory: /sys/kernel/debug/opp and then
device specific directories (based on device names) inside it. For
example: 'cpu0', 'cpu1', etc..
If multiple devices share the OPP table, then the real directory is
created only for the first device. For all others, links are created to
the real directory.
Inside the device specific directory, a separate directory is created
for each OPP. And within that files per opp property.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
dev_opp_list_lock is used everywhere to protect device and OPP lists,
but dev_pm_opp_set_sharing_cpus() is missed somehow. And instead we used
rcu-lock, which wouldn't help here as we are adding a new list_dev.
This also fixes a problem where we have called kzalloc(..., GFP_KERNEL)
from within rcu-lock, which isn't allowed as kzalloc can sleep when
called with GFP_KERNEL.
With CONFIG_DEBUG_ATOMIC_SLEEP set, we get following lockdep-splat:
include/linux/rcupdate.h:578 Illegal context switch in RCU read-side critical section!
other info that might help us debug this:
rcu_scheduler_active = 1, debug_locks = 0
5 locks held by swapper/0/1:
#0: (&dev->mutex){......}, at: [<c02f68f4>] __driver_attach+0x48/0x98
#1: (&dev->mutex){......}, at: [<c02f6904>] __driver_attach+0x58/0x98
#2: (cpu_hotplug.lock){++++++}, at: [<c00249d0>] get_online_cpus+0x40/0xb0
#3: (subsys mutex#5){+.+.+.}, at: [<c02f4f8c>] subsys_interface_register+0x44/0xdc
#4: (rcu_read_lock){......}, at: [<c0305c80>] dev_pm_opp_set_sharing_cpus+0x0/0x1e4
stack backtrace:
CPU: 1 PID: 1 Comm: swapper/0 Tainted: G W 4.3.0-rc7-00047-g81f5932958a8 #59
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[<c0016874>] (unwind_backtrace) from [<c001355c>] (show_stack+0x10/0x14)
[<c001355c>] (show_stack) from [<c022553c>] (dump_stack+0x94/0xbc)
[<c022553c>] (dump_stack) from [<c004904c>] (___might_sleep+0x24c/0x298)
[<c004904c>] (___might_sleep) from [<c00f07e4>] (kmem_cache_alloc+0xe8/0x164)
[<c00f07e4>] (kmem_cache_alloc) from [<c0305354>] (_add_list_dev+0x30/0x58)
[<c0305354>] (_add_list_dev) from [<c0305d50>] (dev_pm_opp_set_sharing_cpus+0xd0/0x1e4)
[<c0305d50>] (dev_pm_opp_set_sharing_cpus) from [<c040eda4>] (cpufreq_init+0x4cc/0x62c)
[<c040eda4>] (cpufreq_init) from [<c040a964>] (cpufreq_online+0xbc/0x73c)
[<c040a964>] (cpufreq_online) from [<c02f4fe0>] (subsys_interface_register+0x98/0xdc)
[<c02f4fe0>] (subsys_interface_register) from [<c040a640>] (cpufreq_register_driver+0x110/0x17c)
[<c040a640>] (cpufreq_register_driver) from [<c040ef64>] (dt_cpufreq_probe+0x60/0x8c)
[<c040ef64>] (dt_cpufreq_probe) from [<c02f8084>] (platform_drv_probe+0x44/0xa4)
[<c02f8084>] (platform_drv_probe) from [<c02f67c0>] (driver_probe_device+0x208/0x2f4)
[<c02f67c0>] (driver_probe_device) from [<c02f6940>] (__driver_attach+0x94/0x98)
[<c02f6940>] (__driver_attach) from [<c02f4c1c>] (bus_for_each_dev+0x68/0x9c)
Reported-by: Michael Turquette <mturquette@baylibre.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.3 <stable@vger.kernel.org> # 4.3
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Move cpu device specific code out of generic opp library, and add it to
cpu.c.
Along with that, create a core-internal opp.h header, which will be used
to share structures and function prototypes within opp core.
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
