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authorLinus Torvalds <torvalds@linux-foundation.org>2014-10-09 16:07:43 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2014-10-09 16:07:43 -0400
commitb528392669415dc1e53a047215e5ad6c2de879fc (patch)
treed19aa6e1464ef7c7d9f399ac8ec9a7707e5ba6b4 /Documentation
parent80213c03c4151d900cf293ef0fc51f8d88495e14 (diff)
parent9f1a053296953c69d7f23511db9441290cb89e2c (diff)
Merge tag 'pm+acpi-3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management updates from Rafael Wysocki: "Features-wise, to me the most important this time is a rework of wakeup interrupts handling in the core that makes them work consistently across all of the available sleep states, including suspend-to-idle. Many thanks to Thomas Gleixner for his help with this work. Second is an update of the generic PM domains code that has been in need of some care for quite a while. Unused code is being removed, DT support is being added and domains are now going to be attached to devices in bus type code in analogy with the ACPI PM domain. The majority of work here was done by Ulf Hansson who also has been the most active developer this time. Apart from this we have a traditional ACPICA update, this time to upstream version 20140828 and a few ACPI wakeup interrupts handling patches on top of the general rework mentioned above. There also are several cpufreq commits including renaming the cpufreq-cpu0 driver to cpufreq-dt, as this is what implements generic DT-based cpufreq support, and a new DT-based idle states infrastructure for cpuidle. In addition to that, the ACPI LPSS driver is updated, ACPI support for Apple machines is improved, a few bugs are fixed and a few cleanups are made all over. Finally, the Adaptive Voltage Scaling (AVS) subsystem now has a tree maintained by Kevin Hilman that will be merged through the PM tree. Numbers-wise, the generic PM domains update takes the lead this time with 32 non-merge commits, second is cpufreq (15 commits) and the 3rd place goes to the wakeup interrupts handling rework (13 commits). Specifics: - Rework the handling of wakeup IRQs by the IRQ core such that all of them will be switched over to "wakeup" mode in suspend_device_irqs() and in that mode the first interrupt will abort system suspend in progress or wake up the system if already in suspend-to-idle (or equivalent) without executing any interrupt handlers. Among other things that eliminates the wakeup-related motivation to use the IRQF_NO_SUSPEND interrupt flag with interrupts which don't really need it and should not use it (Thomas Gleixner and Rafael Wysocki) - Switch over ACPI to handling wakeup interrupts with the help of the new mechanism introduced by the above IRQ core rework (Rafael Wysocki) - Rework the core generic PM domains code to eliminate code that's not used, add DT support and add a generic mechanism by which devices can be added to PM domains automatically during enumeration (Ulf Hansson, Geert Uytterhoeven and Tomasz Figa). - Add debugfs-based mechanics for debugging generic PM domains (Maciej Matraszek). - ACPICA update to upstream version 20140828. Included are updates related to the SRAT and GTDT tables and the _PSx methods are in the METHOD_NAME list now (Bob Moore and Hanjun Guo). - Add _OSI("Darwin") support to the ACPI core (unfortunately, that can't really be done in a straightforward way) to prevent Thunderbolt from being turned off on Apple systems after boot (or after resume from system suspend) and rework the ACPI Smart Battery Subsystem (SBS) driver to work correctly with Apple platforms (Matthew Garrett and Andreas Noever). - ACPI LPSS (Low-Power Subsystem) driver update cleaning up the code, adding support for 133MHz I2C source clock on Intel Baytrail to it and making it avoid using UART RTS override with Auto Flow Control (Heikki Krogerus). - ACPI backlight updates removing the video_set_use_native_backlight quirk which is not necessary any more, making the code check the list of output devices returned by the _DOD method to avoid creating acpi_video interfaces that won't work and adding a quirk for Lenovo Ideapad Z570 (Hans de Goede, Aaron Lu and Stepan Bujnak) - New Win8 ACPI OSI quirks for some Dell laptops (Edward Lin) - Assorted ACPI code cleanups (Fabian Frederick, Rasmus Villemoes, Sudip Mukherjee, Yijing Wang, and Zhang Rui) - cpufreq core updates and cleanups (Viresh Kumar, Preeti U Murthy, Rasmus Villemoes) - cpufreq driver updates: cpufreq-cpu0/cpufreq-dt (driver name change among other things), ppc-corenet, powernv (Viresh Kumar, Preeti U Murthy, Shilpasri G Bhat, Lucas Stach) - cpuidle support for DT-based idle states infrastructure, new ARM64 cpuidle driver, cpuidle core cleanups (Lorenzo Pieralisi, Rasmus Villemoes) - ARM big.LITTLE cpuidle driver updates: support for DT-based initialization and Exynos5800 compatible string (Lorenzo Pieralisi, Kevin Hilman) - Rework of the test_suspend kernel command line argument and a new trace event for console resume (Srinivas Pandruvada, Todd E Brandt) - Second attempt to optimize swsusp_free() (hibernation core) to make it avoid going through all PFNs which may be way too slow on some systems (Joerg Roedel) - devfreq updates (Paul Bolle, Punit Agrawal, Ãrjan Eide). - rockchip-io Adaptive Voltage Scaling (AVS) driver and AVS entry update in MAINTAINERS (Heiko Stübner, Kevin Hilman) - PM core fix related to clock management (Geert Uytterhoeven) - PM core's sysfs code cleanup (Johannes Berg)" * tag 'pm+acpi-3.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (105 commits) ACPI / fan: printk replacement PM / clk: Fix crash in clocks management code if !CONFIG_PM_RUNTIME PM / Domains: Rename cpu_data to cpuidle_data cpufreq: cpufreq-dt: fix potential double put of cpu OF node cpufreq: cpu0: rename driver and internals to 'cpufreq_dt' PM / hibernate: Iterate over set bits instead of PFNs in swsusp_free() cpufreq: ppc-corenet: remove duplicate update of cpu_data ACPI / sleep: Rework the handling of ACPI GPE wakeup from suspend-to-idle PM / sleep: Rename platform suspend/resume functions in suspend.c PM / sleep: Export dpm_suspend_late/noirq() and dpm_resume_early/noirq() ACPICA: Introduce acpi_enable_all_wakeup_gpes() ACPICA: Clear all non-wakeup GPEs in acpi_hw_enable_wakeup_gpe_block() ACPI / video: check _DOD list when creating backlight devices PM / Domains: Move dev_pm_domain_attach|detach() to pm_domain.h cpufreq: Replace strnicmp with strncasecmp cpufreq: powernv: Set the cpus to nominal frequency during reboot/kexec cpufreq: powernv: Set the pstate of the last hotplugged out cpu in policy->cpus to minimum cpufreq: Allow stop CPU callback to be used by all cpufreq drivers PM / devfreq: exynos: Enable building exynos PPMU as module PM / devfreq: Export helper functions for drivers ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/arm/exynos/power_domain.txt13
-rw-r--r--Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt (renamed from Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt)8
-rw-r--r--Documentation/devicetree/bindings/power/power_domain.txt49
-rw-r--r--Documentation/devicetree/bindings/power/rockchip-io-domain.txt83
-rw-r--r--Documentation/kernel-parameters.txt10
-rw-r--r--Documentation/power/suspend-and-interrupts.txt123
6 files changed, 271 insertions, 15 deletions
diff --git a/Documentation/devicetree/bindings/arm/exynos/power_domain.txt b/Documentation/devicetree/bindings/arm/exynos/power_domain.txt
index 8b4f7b7fe88b..abde1ea8a119 100644
--- a/Documentation/devicetree/bindings/arm/exynos/power_domain.txt
+++ b/Documentation/devicetree/bindings/arm/exynos/power_domain.txt
@@ -8,6 +8,8 @@ Required Properties:
* samsung,exynos4210-pd - for exynos4210 type power domain.
- reg: physical base address of the controller and length of memory mapped
region.
+- #power-domain-cells: number of cells in power domain specifier;
+ must be 0.
Optional Properties:
- clocks: List of clock handles. The parent clocks of the input clocks to the
@@ -29,6 +31,7 @@ Example:
lcd0: power-domain-lcd0 {
compatible = "samsung,exynos4210-pd";
reg = <0x10023C00 0x10>;
+ #power-domain-cells = <0>;
};
mfc_pd: power-domain@10044060 {
@@ -37,12 +40,8 @@ Example:
clocks = <&clock CLK_FIN_PLL>, <&clock CLK_MOUT_SW_ACLK333>,
<&clock CLK_MOUT_USER_ACLK333>;
clock-names = "oscclk", "pclk0", "clk0";
+ #power-domain-cells = <0>;
};
-Example of the node using power domain:
-
- node {
- /* ... */
- samsung,power-domain = <&lcd0>;
- /* ... */
- };
+See Documentation/devicetree/bindings/power/power_domain.txt for description
+of consumer-side bindings.
diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt
index 366690cb86a3..e41c98ffbccb 100644
--- a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt
@@ -1,8 +1,8 @@
-Generic CPU0 cpufreq driver
+Generic cpufreq driver
-It is a generic cpufreq driver for CPU0 frequency management. It
-supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
-systems which share clock and voltage across all CPUs.
+It is a generic DT based cpufreq driver for frequency management. It supports
+both uniprocessor (UP) and symmetric multiprocessor (SMP) systems which share
+clock and voltage across all CPUs.
Both required and optional properties listed below must be defined
under node /cpus/cpu@0.
diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt
new file mode 100644
index 000000000000..98c16672ab5f
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/power_domain.txt
@@ -0,0 +1,49 @@
+* Generic PM domains
+
+System on chip designs are often divided into multiple PM domains that can be
+used for power gating of selected IP blocks for power saving by reduced leakage
+current.
+
+This device tree binding can be used to bind PM domain consumer devices with
+their PM domains provided by PM domain providers. A PM domain provider can be
+represented by any node in the device tree and can provide one or more PM
+domains. A consumer node can refer to the provider by a phandle and a set of
+phandle arguments (so called PM domain specifiers) of length specified by the
+#power-domain-cells property in the PM domain provider node.
+
+==PM domain providers==
+
+Required properties:
+ - #power-domain-cells : Number of cells in a PM domain specifier;
+ Typically 0 for nodes representing a single PM domain and 1 for nodes
+ providing multiple PM domains (e.g. power controllers), but can be any value
+ as specified by device tree binding documentation of particular provider.
+
+Example:
+
+ power: power-controller@12340000 {
+ compatible = "foo,power-controller";
+ reg = <0x12340000 0x1000>;
+ #power-domain-cells = <1>;
+ };
+
+The node above defines a power controller that is a PM domain provider and
+expects one cell as its phandle argument.
+
+==PM domain consumers==
+
+Required properties:
+ - power-domains : A phandle and PM domain specifier as defined by bindings of
+ the power controller specified by phandle.
+
+Example:
+
+ leaky-device@12350000 {
+ compatible = "foo,i-leak-current";
+ reg = <0x12350000 0x1000>;
+ power-domains = <&power 0>;
+ };
+
+The node above defines a typical PM domain consumer device, which is located
+inside a PM domain with index 0 of a power controller represented by a node
+with the label "power".
diff --git a/Documentation/devicetree/bindings/power/rockchip-io-domain.txt b/Documentation/devicetree/bindings/power/rockchip-io-domain.txt
new file mode 100644
index 000000000000..6fbf6e7ecde6
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/rockchip-io-domain.txt
@@ -0,0 +1,83 @@
+Rockchip SRAM for IO Voltage Domains:
+-------------------------------------
+
+IO domain voltages on some Rockchip SoCs are variable but need to be
+kept in sync between the regulators and the SoC using a special
+register.
+
+A specific example using rk3288:
+- If the regulator hooked up to a pin like SDMMC0_VDD is 3.3V then
+ bit 7 of GRF_IO_VSEL needs to be 0. If the regulator hooked up to
+ that same pin is 1.8V then bit 7 of GRF_IO_VSEL needs to be 1.
+
+Said another way, this driver simply handles keeping bits in the SoC's
+general register file (GRF) in sync with the actual value of a voltage
+hooked up to the pins.
+
+Note that this driver specifically doesn't include:
+- any logic for deciding what voltage we should set regulators to
+- any logic for deciding whether regulators (or internal SoC blocks)
+ should have power or not have power
+
+If there were some other software that had the smarts of making
+decisions about regulators, it would work in conjunction with this
+driver. When that other software adjusted a regulator's voltage then
+this driver would handle telling the SoC about it. A good example is
+vqmmc for SD. In that case the dw_mmc driver simply is told about a
+regulator. It changes the regulator between 3.3V and 1.8V at the
+right time. This driver notices the change and makes sure that the
+SoC is on the same page.
+
+
+Required properties:
+- compatible: should be one of:
+ - "rockchip,rk3188-io-voltage-domain" for rk3188
+ - "rockchip,rk3288-io-voltage-domain" for rk3288
+- rockchip,grf: phandle to the syscon managing the "general register files"
+
+
+You specify supplies using the standard regulator bindings by including
+a phandle the the relevant regulator. All specified supplies must be able
+to report their voltage. The IO Voltage Domain for any non-specified
+supplies will be not be touched.
+
+Possible supplies for rk3188:
+- ap0-supply: The supply connected to AP0_VCC.
+- ap1-supply: The supply connected to AP1_VCC.
+- cif-supply: The supply connected to CIF_VCC.
+- flash-supply: The supply connected to FLASH_VCC.
+- lcdc0-supply: The supply connected to LCD0_VCC.
+- lcdc1-supply: The supply connected to LCD1_VCC.
+- vccio0-supply: The supply connected to VCCIO0.
+- vccio1-supply: The supply connected to VCCIO1.
+ Sometimes also labeled VCCIO1 and VCCIO2.
+
+Possible supplies for rk3288:
+- audio-supply: The supply connected to APIO4_VDD.
+- bb-supply: The supply connected to APIO5_VDD.
+- dvp-supply: The supply connected to DVPIO_VDD.
+- flash0-supply: The supply connected to FLASH0_VDD. Typically for eMMC
+- flash1-supply: The supply connected to FLASH1_VDD. Also known as SDIO1.
+- gpio30-supply: The supply connected to APIO1_VDD.
+- gpio1830 The supply connected to APIO2_VDD.
+- lcdc-supply: The supply connected to LCDC_VDD.
+- sdcard-supply: The supply connected to SDMMC0_VDD.
+- wifi-supply: The supply connected to APIO3_VDD. Also known as SDIO0.
+
+
+Example:
+
+ io-domains {
+ compatible = "rockchip,rk3288-io-voltage-domain";
+ rockchip,grf = <&grf>;
+
+ audio-supply = <&vcc18_codec>;
+ bb-supply = <&vcc33_io>;
+ dvp-supply = <&vcc_18>;
+ flash0-supply = <&vcc18_flashio>;
+ gpio1830-supply = <&vcc33_io>;
+ gpio30-supply = <&vcc33_pmuio>;
+ lcdc-supply = <&vcc33_lcd>;
+ sdcard-supply = <&vccio_sd>;
+ wifi-supply = <&vcc18_wl>;
+ };
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index d9a452e8fb9b..cc4ab2517abc 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -3321,11 +3321,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
tdfx= [HW,DRM]
- test_suspend= [SUSPEND]
+ test_suspend= [SUSPEND][,N]
Specify "mem" (for Suspend-to-RAM) or "standby" (for
- standby suspend) as the system sleep state to briefly
- enter during system startup. The system is woken from
- this state using a wakeup-capable RTC alarm.
+ standby suspend) or "freeze" (for suspend type freeze)
+ as the system sleep state during system startup with
+ the optional capability to repeat N number of times.
+ The system is woken from this state using a
+ wakeup-capable RTC alarm.
thash_entries= [KNL,NET]
Set number of hash buckets for TCP connection
diff --git a/Documentation/power/suspend-and-interrupts.txt b/Documentation/power/suspend-and-interrupts.txt
new file mode 100644
index 000000000000..69663640dea5
--- /dev/null
+++ b/Documentation/power/suspend-and-interrupts.txt
@@ -0,0 +1,123 @@
+System Suspend and Device Interrupts
+
+Copyright (C) 2014 Intel Corp.
+Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+
+
+Suspending and Resuming Device IRQs
+-----------------------------------
+
+Device interrupt request lines (IRQs) are generally disabled during system
+suspend after the "late" phase of suspending devices (that is, after all of the
+->prepare, ->suspend and ->suspend_late callbacks have been executed for all
+devices). That is done by suspend_device_irqs().
+
+The rationale for doing so is that after the "late" phase of device suspend
+there is no legitimate reason why any interrupts from suspended devices should
+trigger and if any devices have not been suspended properly yet, it is better to
+block interrupts from them anyway. Also, in the past we had problems with
+interrupt handlers for shared IRQs that device drivers implementing them were
+not prepared for interrupts triggering after their devices had been suspended.
+In some cases they would attempt to access, for example, memory address spaces
+of suspended devices and cause unpredictable behavior to ensue as a result.
+Unfortunately, such problems are very difficult to debug and the introduction
+of suspend_device_irqs(), along with the "noirq" phase of device suspend and
+resume, was the only practical way to mitigate them.
+
+Device IRQs are re-enabled during system resume, right before the "early" phase
+of resuming devices (that is, before starting to execute ->resume_early
+callbacks for devices). The function doing that is resume_device_irqs().
+
+
+The IRQF_NO_SUSPEND Flag
+------------------------
+
+There are interrupts that can legitimately trigger during the entire system
+suspend-resume cycle, including the "noirq" phases of suspending and resuming
+devices as well as during the time when nonboot CPUs are taken offline and
+brought back online. That applies to timer interrupts in the first place,
+but also to IPIs and to some other special-purpose interrupts.
+
+The IRQF_NO_SUSPEND flag is used to indicate that to the IRQ subsystem when
+requesting a special-purpose interrupt. It causes suspend_device_irqs() to
+leave the corresponding IRQ enabled so as to allow the interrupt to work all
+the time as expected.
+
+Note that the IRQF_NO_SUSPEND flag affects the entire IRQ and not just one
+user of it. Thus, if the IRQ is shared, all of the interrupt handlers installed
+for it will be executed as usual after suspend_device_irqs(), even if the
+IRQF_NO_SUSPEND flag was not passed to request_irq() (or equivalent) by some of
+the IRQ's users. For this reason, using IRQF_NO_SUSPEND and IRQF_SHARED at the
+same time should be avoided.
+
+
+System Wakeup Interrupts, enable_irq_wake() and disable_irq_wake()
+------------------------------------------------------------------
+
+System wakeup interrupts generally need to be configured to wake up the system
+from sleep states, especially if they are used for different purposes (e.g. as
+I/O interrupts) in the working state.
+
+That may involve turning on a special signal handling logic within the platform
+(such as an SoC) so that signals from a given line are routed in a different way
+during system sleep so as to trigger a system wakeup when needed. For example,
+the platform may include a dedicated interrupt controller used specifically for
+handling system wakeup events. Then, if a given interrupt line is supposed to
+wake up the system from sleep sates, the corresponding input of that interrupt
+controller needs to be enabled to receive signals from the line in question.
+After wakeup, it generally is better to disable that input to prevent the
+dedicated controller from triggering interrupts unnecessarily.
+
+The IRQ subsystem provides two helper functions to be used by device drivers for
+those purposes. Namely, enable_irq_wake() turns on the platform's logic for
+handling the given IRQ as a system wakeup interrupt line and disable_irq_wake()
+turns that logic off.
+
+Calling enable_irq_wake() causes suspend_device_irqs() to treat the given IRQ
+in a special way. Namely, the IRQ remains enabled, by on the first interrupt
+it will be disabled, marked as pending and "suspended" so that it will be
+re-enabled by resume_device_irqs() during the subsequent system resume. Also
+the PM core is notified about the event which casues the system suspend in
+progress to be aborted (that doesn't have to happen immediately, but at one
+of the points where the suspend thread looks for pending wakeup events).
+
+This way every interrupt from a wakeup interrupt source will either cause the
+system suspend currently in progress to be aborted or wake up the system if
+already suspended. However, after suspend_device_irqs() interrupt handlers are
+not executed for system wakeup IRQs. They are only executed for IRQF_NO_SUSPEND
+IRQs at that time, but those IRQs should not be configured for system wakeup
+using enable_irq_wake().
+
+
+Interrupts and Suspend-to-Idle
+------------------------------
+
+Suspend-to-idle (also known as the "freeze" sleep state) is a relatively new
+system sleep state that works by idling all of the processors and waiting for
+interrupts right after the "noirq" phase of suspending devices.
+
+Of course, this means that all of the interrupts with the IRQF_NO_SUSPEND flag
+set will bring CPUs out of idle while in that state, but they will not cause the
+IRQ subsystem to trigger a system wakeup.
+
+System wakeup interrupts, in turn, will trigger wakeup from suspend-to-idle in
+analogy with what they do in the full system suspend case. The only difference
+is that the wakeup from suspend-to-idle is signaled using the usual working
+state interrupt delivery mechanisms and doesn't require the platform to use
+any special interrupt handling logic for it to work.
+
+
+IRQF_NO_SUSPEND and enable_irq_wake()
+-------------------------------------
+
+There are no valid reasons to use both enable_irq_wake() and the IRQF_NO_SUSPEND
+flag on the same IRQ.
+
+First of all, if the IRQ is not shared, the rules for handling IRQF_NO_SUSPEND
+interrupts (interrupt handlers are invoked after suspend_device_irqs()) are
+directly at odds with the rules for handling system wakeup interrupts (interrupt
+handlers are not invoked after suspend_device_irqs()).
+
+Second, both enable_irq_wake() and IRQF_NO_SUSPEND apply to entire IRQs and not
+to individual interrupt handlers, so sharing an IRQ between a system wakeup
+interrupt source and an IRQF_NO_SUSPEND interrupt source does not make sense.