This commit defines an interface allowing multi-phase reset. The phases are INIT, HOLD and EXIT.
The reset of a Resettable is controlled with 2 functions: - resettable_assert_reset which starts the reset operation. - resettable_deassert_reset which ends the reset operation. There is also a `resettable_reset` helper function which does assert then deassert allowing to do a proper reset in one call. The interface only contains 3 methods, one per phase. Each method should handle reset of the object and its sub-elements. Signed-off-by: Damien Hedde <damien.he...@greensocs.com> --- hw/core/Makefile.objs | 1 + hw/core/resettable.c | 69 ++++++++++++++++++++++++++++++++++ include/hw/resettable.h | 83 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 153 insertions(+) create mode 100644 hw/core/resettable.c create mode 100644 include/hw/resettable.h diff --git a/hw/core/Makefile.objs b/hw/core/Makefile.objs index a799c83815..97007454a8 100644 --- a/hw/core/Makefile.objs +++ b/hw/core/Makefile.objs @@ -1,6 +1,7 @@ # core qdev-related obj files, also used by *-user: common-obj-y += qdev.o qdev-properties.o common-obj-y += bus.o reset.o +common-obj-y += resettable.o common-obj-$(CONFIG_SOFTMMU) += qdev-fw.o common-obj-$(CONFIG_SOFTMMU) += fw-path-provider.o # irq.o needed for qdev GPIO handling: diff --git a/hw/core/resettable.c b/hw/core/resettable.c new file mode 100644 index 0000000000..6ea1e5b54a --- /dev/null +++ b/hw/core/resettable.c @@ -0,0 +1,69 @@ +/* + * Resettable interface. + * + * 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. + */ + +#include "qemu/osdep.h" +#include "qemu/module.h" +#include "hw/resettable.h" + +#define RESETTABLE_GET_CLASS(obj) \ + OBJECT_GET_CLASS(ResettableClass, (obj), TYPE_RESETTABLE) + +void resettable_init_phase(Object *obj, bool cold) +{ + ResettableClass *rc = RESETTABLE_GET_CLASS(obj); + + if (rc->phases.init) { + rc->phases.init(obj, cold); + } +} + +void resettable_hold_phase(Object *obj) +{ + ResettableClass *rc = RESETTABLE_GET_CLASS(obj); + + if (rc->phases.hold) { + rc->phases.hold(obj); + } +} + +void resettable_exit_phase(Object *obj) +{ + ResettableClass *rc = RESETTABLE_GET_CLASS(obj); + + if (rc->phases.exit) { + rc->phases.exit(obj); + } +} + +void resettable_assert_reset(Object *obj, bool cold) +{ + resettable_init_phase(obj, cold); + resettable_hold_phase(obj); +} + +void resettable_deassert_reset(Object *obj) +{ + resettable_exit_phase(obj); +} + +static const TypeInfo resettable_interface_info = { + .name = TYPE_RESETTABLE, + .parent = TYPE_INTERFACE, + .class_size = sizeof(ResettableClass), +}; + +static void reset_register_types(void) +{ + type_register_static(&resettable_interface_info); +} + +type_init(reset_register_types) diff --git a/include/hw/resettable.h b/include/hw/resettable.h new file mode 100644 index 0000000000..15d5bd878d --- /dev/null +++ b/include/hw/resettable.h @@ -0,0 +1,83 @@ +#ifndef HW_RESETTABLE_H +#define HW_RESETTABLE_H + +#include "qom/object.h" + +#define TYPE_RESETTABLE "resettable" + +#define RESETTABLE_CLASS(class) \ + OBJECT_CLASS_CHECK(ResettableClass, (class), TYPE_RESETTABLE) + +/* + * ResettableClass: + * Interface for resettable objects. + * + * The reset operation is divided in several phases each represented by a + * method. + * + * @phases.init: should reset local state only. Takes a bool @cold argument + * specifying whether the reset is cold or warm. It must not do side-effect + * on others objects. + * + * @phases.hold: side-effects action on others objects due to staying in a + * resetting state. + * + * @phases.exit: leave the reset state, may do side-effects action on others + * objects. + * + * "Entering the reset state" corresponds to the init and hold phases. + * "Leaving the reset state" corresponds to the exit phase. + */ +typedef void (*ResettableInitPhase)(Object *obj, bool cold); +typedef void (*ResettableHoldPhase)(Object *obj); +typedef void (*ResettableExitPhase)(Object *obj); +typedef struct ResettableClass { + InterfaceClass parent_class; + + struct ResettablePhases { + ResettableInitPhase init; + ResettableHoldPhase hold; + ResettableExitPhase exit; + } phases; +} ResettableClass; +typedef struct ResettablePhases ResettablePhases; + +/* + * Helpers to do a single phase of a Resettable. + * Call the corresponding ResettableClass method if it is not NULL. + */ +void resettable_init_phase(Object *obj, bool cold); +void resettable_hold_phase(Object *obj); +void resettable_exit_phase(Object *obj); + +/** + * resettable_assert_reset: + * Put an object in reset state. + * Each time resettable_assert_reset is called, resettable_deassert_reset + * must be eventually called once and only once. + * + * @obj object to reset, must implement Resettable interface. + * @cold boolean indicating the type of reset (cold or warm) + */ +void resettable_assert_reset(Object *obj, bool cold); + +/** + * resettable_deassert_reset: + * End the reset state if an object. + * + * @obj object to reset, must implement Resettable interface. + */ +void resettable_deassert_reset(Object *obj); + +/** + * resettable_reset: + * Calling this function is equivalent to call @assert_reset then + * @deassert_reset. + */ +static inline void resettable_reset(Object *obj, bool cold) +{ + resettable_assert_reset(obj, cold); + resettable_deassert_reset(obj); +} + +#endif -- 2.21.0