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| author | Peter Maydell <peter.maydell@linaro.org> | 2020-01-30 16:19:04 +0000 |
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| committer | Peter Maydell <peter.maydell@linaro.org> | 2020-01-30 16:19:04 +0000 |
| commit | 928173659d6e5dc368284f73f90ea1d129e1f57d (patch) | |
| tree | a7c20f44a7f47478a8b475fb42609af5d2977f64 /include/hw/resettable.h | |
| parent | 204aa60b37c23a89e690d418f49787d274303ca7 (diff) | |
| parent | dea101a1ae9968c9fec6ab0291489dad7c49f36f (diff) | |
| download | focaccia-qemu-928173659d6e5dc368284f73f90ea1d129e1f57d.tar.gz focaccia-qemu-928173659d6e5dc368284f73f90ea1d129e1f57d.zip | |
Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20200130' into staging
target-arm queue: * hw/core/or-irq: Fix incorrect assert forbidding num-lines == MAX_OR_LINES * target/arm/arm-semi: Don't let the guest close stdin/stdout/stderr * aspeed: some minor bugfixes * aspeed: add eMMC controller model for AST2600 SoC * hw/arm/raspi: Remove obsolete use of -smp to set the soc 'enabled-cpus' * New 3-phase reset API for device models * hw/intc/arm_gicv3_kvm: Stop wrongly programming GICR_PENDBASER.PTZ bit * Arm KVM: stop/restart the guest counter when the VM is stopped and started # gpg: Signature made Thu 30 Jan 2020 16:14:45 GMT # gpg: using RSA key E1A5C593CD419DE28E8315CF3C2525ED14360CDE # gpg: issuer "peter.maydell@linaro.org" # gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [ultimate] # gpg: aka "Peter Maydell <pmaydell@gmail.com>" [ultimate] # gpg: aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [ultimate] # Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83 15CF 3C25 25ED 1436 0CDE * remotes/pmaydell/tags/pull-target-arm-20200130: (26 commits) target/arm/cpu: Add the kvm-no-adjvtime CPU property target/arm/kvm: Implement virtual time adjustment tests/arm-cpu-features: Check feature default values target/arm/kvm64: kvm64 cpus have timer registers hw/arm/virt: Add missing 5.0 options call to 4.2 options target/arm/kvm: trivial: Clean up header documentation hw/intc/arm_gicv3_kvm: Stop wrongly programming GICR_PENDBASER.PTZ bit hw/s390x/ipl: replace deprecated qdev_reset_all registration vl: replace deprecated qbus_reset_all registration docs/devel/reset.rst: add doc about Resettable interface hw/core: deprecate old reset functions and introduce new ones hw/core/qdev: update hotplug reset regarding resettable hw/core/qdev: handle parent bus change regarding resettable hw/core/resettable: add support for changing parent hw/core: add Resettable support to BusClass and DeviceClass hw/core: create Resettable QOM interface hw/core/qdev: add trace events to help with resettable transition add device_legacy_reset function to prepare for reset api change hw/arm/raspi: Remove obsolete use of -smp to set the soc 'enabled-cpus' misc/pca9552: Add qom set and get ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'include/hw/resettable.h')
| -rw-r--r-- | include/hw/resettable.h | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/include/hw/resettable.h b/include/hw/resettable.h new file mode 100644 index 0000000000..f4c4bab0ef --- /dev/null +++ b/include/hw/resettable.h @@ -0,0 +1,247 @@ +/* + * Resettable interface header. + * + * Copyright (c) 2019 GreenSocs SAS + * + * Authors: + * Damien Hedde + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef HW_RESETTABLE_H +#define HW_RESETTABLE_H + +#include "qom/object.h" + +#define TYPE_RESETTABLE_INTERFACE "resettable" + +#define RESETTABLE_CLASS(class) \ + OBJECT_CLASS_CHECK(ResettableClass, (class), TYPE_RESETTABLE_INTERFACE) + +#define RESETTABLE_GET_CLASS(obj) \ + OBJECT_GET_CLASS(ResettableClass, (obj), TYPE_RESETTABLE_INTERFACE) + +typedef struct ResettableState ResettableState; + +/** + * ResetType: + * Types of reset. + * + * + Cold: reset resulting from a power cycle of the object. + * + * TODO: Support has to be added to handle more types. In particular, + * ResettableState structure needs to be expanded. + */ +typedef enum ResetType { + RESET_TYPE_COLD, +} ResetType; + +/* + * ResettableClass: + * Interface for resettable objects. + * + * See docs/devel/reset.rst for more detailed information about how QEMU models + * reset. This whole API must only be used when holding the iothread mutex. + * + * All objects which can be reset must implement this interface; + * it is usually provided by a base class such as DeviceClass or BusClass. + * Every Resettable object must maintain some state tracking the + * progress of a reset operation by providing a ResettableState structure. + * The functions defined in this module take care of updating the + * state of the reset. + * The base class implementation of the interface provides this + * state and implements the associated method: get_state. + * + * Concrete object implementations (typically specific devices + * such as a UART model) should provide the functions + * for the phases.enter, phases.hold and phases.exit methods, which + * they can set in their class init function, either directly or + * by calling resettable_class_set_parent_phases(). + * The phase methods are guaranteed to only only ever be called once + * for any reset event, in the order 'enter', 'hold', 'exit'. + * An object will always move quickly from 'enter' to 'hold' + * but might remain in 'hold' for an arbitrary period of time + * before eventually reset is deasserted and the 'exit' phase is called. + * Object implementations should be prepared for functions handling + * inbound connections from other devices (such as qemu_irq handler + * functions) to be called at any point during reset after their + * 'enter' method has been called. + * + * Users of a resettable object should not call these methods + * directly, but instead use the function resettable_reset(). + * + * @phases.enter: This phase is called when the object enters reset. It + * should reset local state of the object, but it must not do anything that + * has a side-effect on other objects, such as raising or lowering a qemu_irq + * line or reading or writing guest memory. It takes the reset's type as + * argument. + * + * @phases.hold: This phase is called for entry into reset, once every object + * in the system which is being reset has had its @phases.enter method called. + * At this point devices can do actions that affect other objects. + * + * @phases.exit: This phase is called when the object leaves the reset state. + * Actions affecting other objects are permitted. + * + * @get_state: Mandatory method which must return a pointer to a + * ResettableState. + * + * @get_transitional_function: transitional method to handle Resettable objects + * not yet fully moved to this interface. It will be removed as soon as it is + * not needed anymore. This method is optional and may return a pointer to a + * function to be used instead of the phases. If the method exists and returns + * a non-NULL function pointer then that function is executed as a replacement + * of the 'hold' phase method taking the object as argument. The two other phase + * methods are not executed. + * + * @child_foreach: Executes a given callback on every Resettable child. Child + * in this context means a child in the qbus tree, so the children of a qbus + * are the devices on it, and the children of a device are all the buses it + * owns. This is not the same as the QOM object hierarchy. The function takes + * additional opaque and ResetType arguments which must be passed unmodified to + * the callback. + */ +typedef void (*ResettableEnterPhase)(Object *obj, ResetType type); +typedef void (*ResettableHoldPhase)(Object *obj); +typedef void (*ResettableExitPhase)(Object *obj); +typedef ResettableState * (*ResettableGetState)(Object *obj); +typedef void (*ResettableTrFunction)(Object *obj); +typedef ResettableTrFunction (*ResettableGetTrFunction)(Object *obj); +typedef void (*ResettableChildCallback)(Object *, void *opaque, + ResetType type); +typedef void (*ResettableChildForeach)(Object *obj, + ResettableChildCallback cb, + void *opaque, ResetType type); +typedef struct ResettablePhases { + ResettableEnterPhase enter; + ResettableHoldPhase hold; + ResettableExitPhase exit; +} ResettablePhases; +typedef struct ResettableClass { + InterfaceClass parent_class; + + /* Phase methods */ + ResettablePhases phases; + + /* State access method */ + ResettableGetState get_state; + + /* Transitional method for legacy reset compatibility */ + ResettableGetTrFunction get_transitional_function; + + /* Hierarchy handling method */ + ResettableChildForeach child_foreach; +} ResettableClass; + +/** + * ResettableState: + * Structure holding reset related state. The fields should not be accessed + * directly; the definition is here to allow further inclusion into other + * objects. + * + * @count: Number of reset level the object is into. It is incremented when + * the reset operation starts and decremented when it finishes. + * @hold_phase_pending: flag which indicates that we need to invoke the 'hold' + * phase handler for this object. + * @exit_phase_in_progress: true if we are currently in the exit phase + */ +struct ResettableState { + unsigned count; + bool hold_phase_pending; + bool exit_phase_in_progress; +}; + +/** + * resettable_state_clear: + * Clear the state. It puts the state to the initial (zeroed) state required + * to reuse an object. Typically used in realize step of base classes + * implementing the interface. + */ +static inline void resettable_state_clear(ResettableState *state) +{ + memset(state, 0, sizeof(ResettableState)); +} + +/** + * resettable_reset: + * Trigger a reset on an object @obj of type @type. @obj must implement + * Resettable interface. + * + * Calling this function is equivalent to calling @resettable_assert_reset() + * then @resettable_release_reset(). + */ +void resettable_reset(Object *obj, ResetType type); + +/** + * resettable_assert_reset: + * Put an object @obj into reset. @obj must implement Resettable interface. + * + * @resettable_release_reset() must eventually be called after this call. + * There must be one call to @resettable_release_reset() per call of + * @resettable_assert_reset(), with the same type argument. + * + * NOTE: Until support for migration is added, the @resettable_release_reset() + * must not be delayed. It must occur just after @resettable_assert_reset() so + * that migration cannot be triggered in between. Prefer using + * @resettable_reset() for now. + */ +void resettable_assert_reset(Object *obj, ResetType type); + +/** + * resettable_release_reset: + * Release the object @obj from reset. @obj must implement Resettable interface. + * + * See @resettable_assert_reset() description for details. + */ +void resettable_release_reset(Object *obj, ResetType type); + +/** + * resettable_is_in_reset: + * Return true if @obj is under reset. + * + * @obj must implement Resettable interface. + */ +bool resettable_is_in_reset(Object *obj); + +/** + * resettable_change_parent: + * Indicate that the parent of Ressettable @obj is changing from @oldp to @newp. + * All 3 objects must implement resettable interface. @oldp or @newp may be + * NULL. + * + * This function will adapt the reset state of @obj so that it is coherent + * with the reset state of @newp. It may trigger @resettable_assert_reset() + * or @resettable_release_reset(). It will do such things only if the reset + * state of @newp and @oldp are different. + * + * When using this function during reset, it must only be called during + * a hold phase method. Calling this during enter or exit phase is an error. + */ +void resettable_change_parent(Object *obj, Object *newp, Object *oldp); + +/** + * resettable_cold_reset_fn: + * Helper to call resettable_reset((Object *) opaque, RESET_TYPE_COLD). + * + * This function is typically useful to register a reset handler with + * qemu_register_reset. + */ +void resettable_cold_reset_fn(void *opaque); + +/** + * resettable_class_set_parent_phases: + * + * Save @rc current reset phases into @parent_phases and override @rc phases + * by the given new methods (@enter, @hold and @exit). + * Each phase is overridden only if the new one is not NULL allowing to + * override a subset of phases. + */ +void resettable_class_set_parent_phases(ResettableClass *rc, + ResettableEnterPhase enter, + ResettableHoldPhase hold, + ResettableExitPhase exit, + ResettablePhases *parent_phases); + +#endif |