module ti.sysbios.hal.Hwi

Hardware Interrupt Manager Proxy

This module provides APIs for managing hardware interrupts. These APIs are generic across all supported targets and devices and should provide sufficient functionality for most applications. [ more ... ]
C synopsis target-domain sourced in ti/sysbios/hal/Hwi.xdc
#include <ti/sysbios/hal/Hwi.h>
Functions
Void
Void
Void
Void
Functions common to all IHwi modules
Void 
macro UInt 
UInt 
macro UInt 
UInt 
Bool 
Ptr 
Bool 
Void 
macro Void 
Void 
Void 
Void 
Void 
Functions common to all target instances
Functions common to all target modules
Typedefs
typedef Void 
typedef Hwi_Object *
typedef struct
typedef UArg 
typedef enum
typedef struct
typedef struct
typedef struct
typedef struct
Constants
extern const Bool 
extern const Bool 
extern const Bool 
extern const Bool 
extern const Error_Id 
 
DETAILS
This module provides APIs for managing hardware interrupts. These APIs are generic across all supported targets and devices and should provide sufficient functionality for most applications.
The actual implementations of the Hwi module APIs are provided by the Hwi module delegates. Additional, family-specific Hwi module APIs may also be provided by the Hwi module delegates. See the list of Delegate Mappings to determine which Hwi delegate is used for your target/device.
You can statically or dynamically assign functions that run when specific hardware interrupts occur. Dynamic assignment of Hwi functions to interrupts at run-time is done using the Hwi_create function.
Interrupt routines can be written completely in C, completely in assembly, or in a mix of C and assembly. In order to support interrupt routines written completely in C, an interrupt dispatcher is provided that performs the requisite prolog and epilog for an interrupt routine.
Some routines are assigned to interrupts by the other SYS/BIOS modules. For example, the ti.sysbios.knl.Clock module configures its own timer interrupt handler.
CONSTRAINTS
Since the hal Hwi module has no knowledge of the delegate Hwi module's instance definition, Hwi_construct() can NOT be properly supported.
If BIOS.runtimeCreatesEnabled is set to true, both Hwi_create() and Hwi_construct() will attempt to dynamically create (ie NOT construct) a delegate Hwi object.
If BIOS.runtimeCreatesEnabled is set to false, both Hwi_create() and Hwi_construct() will fail.

Calling Context

Function Hwi Swi Task Main Startup
clearInterrupt Y Y Y Y Y
create N N Y Y N
disable Y Y Y Y Y
disableInterrupt Y Y Y Y N
enable Y Y Y N N
enableInterrupt Y Y Y Y N
Params_init Y Y Y Y Y
restore Y Y Y Y Y
restoreInterrupt Y Y Y Y Y
construct N N Y Y N
delete N N Y Y N
destruct N N Y Y N
getHookContext Y Y Y Y N
setFunc Y Y Y Y N
setHookContext Y Y Y Y N
Definitions:
  • Hwi: API is callable from a Hwi thread.
  • Swi: API is callable from a Swi thread.
  • Task: API is callable from a Task thread.
  • Main: API is callable during any of these phases:
    • In your module startup after this module is started (e.g. Hwi_Module_startupDone() returns TRUE).
    • During xdc.runtime.Startup.lastFxns.
    • During main().
    • During BIOS.startupFxns.
  • Startup: API is callable during any of these phases:
    • During xdc.runtime.Startup.firstFxns.
    • In your module startup before this module is started (e.g. Hwi_Module_startupDone() returns FALSE).
RUNTIME HWI CREATION
Below is an example that configures an interrupt at runtime. Typically such code would be placed in main().
  #include <xdc/runtime/Error.h>
  #include <ti/sysbios/hal/Hwi.h>

  Hwi_Handle myHwi;

  Int main(Int argc, char* argv[])
  {
      Hwi_Params hwiParams;
      Error_Block eb;

      Hwi_Params_init(&hwiParams);
      Error_init(&eb);

      // set the argument you want passed to your ISR function
      hwiParams.arg = 1;

      // set the event id of the peripheral assigned to this interrupt
      hwiParams.eventId = 10;

      // don't allow this interrupt to nest itself
      hwiParams.maskSetting = Hwi_MaskingOption_SELF;

      //
      // Configure interrupt 5 to invoke "myIsr".
      // Automatically enables interrupt 5 by default
      // set params.enableInt = FALSE if you want to control
      // when the interrupt is enabled using Hwi_enableInterrupt()
      //

      myHwi = Hwi_create(5, myIsr, &hwiParams, &eb);

      if (Error_check(&eb)) {
          // handle the error
      }
  }

  Void myIsr(UArg arg)
  {
      // this runs when interrupt #5 goes off
  }
HOOK FUNCTIONS
Sets of hook functions can be specified for the Hwi module using the configuration tool. Each set contains these hook functions:
  • Register: A function called before any statically-created Hwis are initialized at runtime. The register hook is called at boot time before main() and before interrupts are enabled.
  • Create: A function that is called when a Hwi is created. This includes hwis that are created statically and those created dynamically using Hwi_create.
  • Begin: A function that is called just prior to running a Hwi.
  • End: A function that is called just after a Hwi finishes.
  • Delete: A function that is called when a Hwi is deleted at run-time with Hwi_delete.
Register Function
The Register function is provided to allow a hook set to store its hookset ID. This id can be passed to Hwi_setHookContext and Hwi_getHookContext to set or get hookset-specific context. The Register function must be specified if the hook implementation needs to use Hwi_setHookContext or Hwi_getHookContext. The registerFxn hook function is called during system initialization before interrupts have been enabled.
  Void myRegisterFxn(Int id);
Create and Delete Functions
The create and delete functions are called whenever a Hwi is created or deleted. They are called with interrupts enabled (unless called at boot time or from main()).
  Void myCreateFxn(Hwi_Handle hwi, Error_Block *eb);
  Void myDeleteFxn(Hwi_Handle hwi);
Begin and End Functions
The beginFxn and endFxn function hooks are called with interrupts globally disabled, therefore any hook processing function will contribute to the overall system interrupt response latency. In order to minimize this impact, carefully consider the processing time spent in an Hwi beginFxn or endFxn function hook.
  Void myBeginFxn(Hwi_Handle hwi);
  Void myEndFxn(Hwi_Handle hwi);
Hook functions can only be configured statically.
 
enum Hwi_MaskingOption

Shorthand interrupt masking options

C synopsis target-domain
typedef enum Hwi_MaskingOption {
    Hwi_MaskingOption_NONE,
    Hwi_MaskingOption_ALL,
    Hwi_MaskingOption_SELF,
    Hwi_MaskingOption_BITMASK,
    Hwi_MaskingOption_LOWER
} Hwi_MaskingOption;
 
VALUES
MaskingOption_NONE — No interrupts are disabled
MaskingOption_ALL — All interrupts are disabled
MaskingOption_SELF — Only this interrupt is disabled
MaskingOption_BITMASK — User supplies interrupt enable masks
MaskingOption_LOWER — All current and lower priority interrupts are disabled.
Only a few targets/devices truly support this masking option. For those that don't, this setting is treated the same as MaskingOption_SELF.
 
typedef Hwi_FuncPtr

Hwi create function type definition

C synopsis target-domain
typedef Void (*Hwi_FuncPtr)(UArg);
 
 
typedef Hwi_Irp

Interrupt Return Pointer

C synopsis target-domain
typedef UArg Hwi_Irp;
 
DETAILS
This is the address of the interrupted instruction.
 
struct Hwi_HookSet

Hwi hook set type definition

C synopsis target-domain
typedef struct Hwi_HookSet {
    Void (*registerFxn)(Int);
    Void (*createFxn)(IHwi_Handle,Error_Block*);
    Void (*beginFxn)(IHwi_Handle);
    Void (*endFxn)(IHwi_Handle);
    Void (*deleteFxn)(IHwi_Handle);
} Hwi_HookSet;
 
DETAILS
The functions that make up a hookSet have certain restrictions. They cannot call any Hwi instance functions other than Hwi_getHookContext() and Hwi_setHookContext(). For all practical purposes, they should treat the Hwi_Handle passed to these functions as an opaque handle.
 
struct Hwi_StackInfo

Structure contains Hwi stack usage info

C synopsis target-domain
typedef struct Hwi_StackInfo {
    SizeT hwiStackPeak;
    SizeT hwiStackSize;
    Ptr hwiStackBase;
} Hwi_StackInfo;
 
DETAILS
Used by getStackInfo() and viewGetStackInfo() functions
 
config Hwi_E_stackOverflow  // module-wide

Error raised when a stack overflow (or corruption) is detected

C synopsis target-domain
extern const Error_Id Hwi_E_stackOverflow;
 
DETAILS
This error is raised by kernel's stack checking function. This function checks the stacks before every task switch to make sure that reserved word at top of stack has not been modified.
The stack checking logic is enabled by the checkStackFlag configuration parameter. If this flag is set to true, the kernel will validate the stacks.
 
config Hwi_dispatcherAutoNestingSupport  // module-wide

Include interrupt nesting logic in interrupt dispatcher?

C synopsis target-domain
extern const Bool Hwi_dispatcherAutoNestingSupport;
 
DETAILS
Default is true.
This option provides the user with the ability to optimize interrupt dispatcher performance when support for interrupt nesting is not required.
Setting this parameter to false will disable the logic in the interrupt dispatcher that manipulates interrupt mask registers and enables and disables interrupts before and after invoking the user's Hwi function.
Set this parameter to false if you don't need interrupts enabled during the execution of your Hwi functions.
 
config Hwi_dispatcherIrpTrackingSupport  // module-wide

Controls whether the dispatcher retains the interrupted thread's return address

C synopsis target-domain
extern const Bool Hwi_dispatcherIrpTrackingSupport;
 
DETAILS
This option is enabled by default.
Setting this parameter to false will disable the logic in the interrupt dispatcher that keeps track of the interrupt's return address and provide a small savings in interrupt latency.
The application can get an interrupt's most recent return address using the getIrp API.
 
config Hwi_dispatcherSwiSupport  // module-wide

Include Swi scheduling logic in interrupt dispatcher?

C synopsis target-domain
extern const Bool Hwi_dispatcherSwiSupport;
 
DETAILS
Default is inherited from BIOS.swiEnabled, which is true by default.
This option provides the user with the ability to optimize interrupt dispatcher performance when it is known that Swis will not be posted from any of their Hwi threads.
WARNING
Setting this parameter to false will disable the logic in the interrupt dispatcher that invokes the Swi scheduler prior to returning from an interrupt. With this setting, Swis MUST NOT be posted from Hwi functions!
 
config Hwi_dispatcherTaskSupport  // module-wide

Include Task scheduling logic in interrupt dispatcher?

C synopsis target-domain
extern const Bool Hwi_dispatcherTaskSupport;
 
DETAILS
Default is inherited from BIOS.taskEnabled, which is true by default.
This option provides the user with the ability to optimize interrupt dispatcher performance when it is known that no Task scheduling APIs (ie Semaphore_post()) will be executed from any of their Hwi threads.
Setting this parameter to false will disable the logic in the interrupt dispatcher that invokes the Task scheduler prior to returning from an interrupt.
 
Hwi_clearInterrupt()  // module-wide

Clear a specific interrupt

C synopsis target-domain
Void Hwi_clearInterrupt(UInt intNum);
 
ARGUMENTS
intNum — interrupt number to clear
DETAILS
Clears a specific interrupt's pending status. The implementation is family-specific.
 
Hwi_disable()  // module-wide

Globally disable interrupts

C synopsis target-domain
macro UInt Hwi_disable();
 
RETURNS
opaque key for use by Hwi_restore()
DETAILS
Hwi_disable globally disables hardware interrupts and returns an opaque key indicating whether interrupts were globally enabled or disabled on entry to Hwi_disable(). The actual value of the key is target/device specific and is meant to be passed to Hwi_restore().
Call Hwi_disable before a portion of a function that needs to run without interruption. When critical processing is complete, call Hwi_restore or Hwi_enable to reenable hardware interrupts.
Servicing of interrupts that occur while interrupts are disabled is postponed until interrupts are reenabled. However, if the same type of interrupt occurs several times while interrupts are disabled, the interrupt's function is executed only once when interrupts are reenabled.
A context switch can occur when calling Hwi_enable or Hwi_restore if an enabled interrupt occurred while interrupts are disabled.
Hwi_disable may be called from main(). However, since Hwi interrupts are already disabled in main(), such a call has no effect.
CONSTRAINTS
If a Task switching API such as Semaphore_pend(), Semaphore_post(), Task_sleep(), or Task_yield() is invoked which results in a context switch while interrupts are disabled, an embedded call to Hwi_enable occurs on the way to the new thread context which unconditionally re-enables interrupts. Interrupts will remain enabled until a subsequent Hwi_disable invocation.
Swis always run with interrupts enabled. See Swi_post() for a discussion Swis and interrupts.
 
Hwi_disableInterrupt()  // module-wide

Disable a specific interrupt

C synopsis target-domain
UInt Hwi_disableInterrupt(UInt intNum);
 
ARGUMENTS
intNum — interrupt number to disable
RETURNS
key to restore previous enable/disable state
DETAILS
Disable a specific interrupt identified by an interrupt number.
 
Hwi_enable()  // module-wide

Globally enable interrupts

C synopsis target-domain
macro UInt Hwi_enable();
 
RETURNS
opaque key for use by Hwi_restore()
DETAILS
Hwi_enable globally enables hardware interrupts and returns an opaque key indicating whether interrupts were globally enabled or disabled on entry to Hwi_enable(). The actual value of the key is target/device specific and is meant to be passed to Hwi_restore().
This function is called as part of SYS/BIOS Startup_POST_APP_MAIN phase.
Hardware interrupts are enabled unless a call to Hwi_disable disables them.
Servicing of interrupts that occur while interrupts are disabled is postponed until interrupts are reenabled. However, if the same type of interrupt occurs several times while interrupts are disabled, the interrupt's function is executed only once when interrupts are reenabled.
A context switch can occur when calling Hwi_enable or Hwi_restore if an enabled interrupt occurred while interrupts are disabled.
Any call to Hwi_enable enables interrupts, even if Hwi_disable has been called several times.
Hwi_enable must not be called from main().
 
Hwi_enableInterrupt()  // module-wide

Enable a specific interrupt

C synopsis target-domain
UInt Hwi_enableInterrupt(UInt intNum);
 
ARGUMENTS
intNum — interrupt number to enable
RETURNS
key to restore previous enable/disable state
DETAILS
Enables a specific interrupt identified by an interrupt number.
 
Hwi_getCoreStackInfo()  // module-wide

Get Hwi stack usage Info for the specified coreId

C synopsis target-domain
Bool Hwi_getCoreStackInfo(IHwi_StackInfo *stkInfo, Bool computeStackDepth, UInt coreId);
 
ARGUMENTS
stkInfo — pointer to structure of type StackInfo
computeStackDepth — decides whether to compute stack depth
coreId — core whose stack info needs to be retrieved
RETURNS
boolean to indicate a stack overflow
DETAILS
getCoreStackInfo returns the Hwi stack usage info for the specified coreId to its calling function by filling stack base address, stack size and stack peak fields in the StackInfo structure.
This function should be used only in applications built with ti.sysbios.BIOS.smpEnabled set to true.
getCoreStackInfo accepts three arguments, a pointer to a structure of type StackInfo, a boolean and a coreId. If the boolean is set to true, the function computes the stack depth and fills the stack peak field in the StackInfo structure. If a stack overflow is detected, the stack depth is not computed. If the boolean is set to false, the function only checks for a stack overflow.
The isr stack is always checked for an overflow and a boolean is returned to indicate whether an overflow occured.
Below is an example of calling getCoreStackInfo() API:
  #include <ti/sysbios/BIOS.h>
  #include <ti/sysbios/hal/Hwi.h>
  #include <ti/sysbios/hal/Core.h>
  #include <ti/sysbios/knl/Task.h>

  ...

  Void idleTask()
  {
      UInt idx;
      Hwi_StackInfo stkInfo;
      Bool stackOverflow = FALSE;

      // Request stack depth for each core's Hwi stack and check for
      // overflow
      for (idx = 0; idx < Core_numCores; idx++) {
          stackOverflow = Hwi_getCoreStackInfo(&stkInfo, TRUE, idx);

          // Alternately, we can omit the request for stack depth and
          // request only the stack base and stack size (the check for
          // stack overflow is always performed):
          //
          // stackOverflow = Hwi_getCoreStackInfo(&stkInfo, FALSE, idx);

          if (stackOverflow) {
              // isr Stack Overflow detected
          }
      }
  }

  Int main(Int argc, char* argv[])
  {
      ...
      BIOS_start();
      return (0);
  }
 
Hwi_getStackInfo()  // module-wide

Get Hwi stack usage Info

C synopsis target-domain
Bool Hwi_getStackInfo(IHwi_StackInfo *stkInfo, Bool computeStackDepth);
 
ARGUMENTS
stkInfo — pointer to structure of type StackInfo
computeStackDepth — decides whether to compute stack depth
RETURNS
boolean to indicate a stack overflow
DETAILS
getStackInfo returns the Hwi stack usage info to its calling function by filling stack base address, stack size and stack peak fields in the StackInfo structure.
getStackInfo accepts two arguments, a pointer to a structure of type StackInfo and a boolean. If the boolean is set to true, the function computes the stack depth and fills the stack peak field in the StackInfo structure. If a stack overflow is detected, the stack depth is not computed. If the boolean is set to false, the function only checks for a stack overflow.
The isr stack is always checked for an overflow and a boolean is returned to indicate whether an overflow occured.
Below is an example of calling getStackInfo() API:
  #include <ti/sysbios/BIOS.h>
  #include <ti/sysbios/hal/Hwi.h>
  #include <ti/sysbios/knl/Swi.h>
  #include <ti/sysbios/knl/Task.h>

  Swi_Handle swi0;
  volatile Bool swiStackOverflow = FALSE;

  Void swi0Fxn(UArg arg1, UArg arg2)
  {
      Hwi_StackInfo stkInfo;

      // Request stack depth
      swiStackOverflow = Hwi_getStackInfo(&stkInfo, TRUE);
 
      // Alternately, we can omit the request for stack depth and 
      // request only the stack base and stack size (the check for
      // stack overflow is always performed):
      //
      // swiStackOverflow = Hwi_getStackInfo(&stkInfo, FALSE);

      if (swiStackOverflow) {
          // isr Stack Overflow detected
      }
  }

  Void idleTask()
  {
      Swi_post(swi0);
  }

  Int main(Int argc, char* argv[])
  {
      swi0 = Swi_create(swi0Fxn, NULL, NULL);

      BIOS_start();
      return (0);
  }
 
Hwi_post()  // module-wide

Generate an interrupt for test purposes

C synopsis target-domain
Void Hwi_post(UInt intNum);
 
ARGUMENTS
intNum — ID of interrupt to generate
 
Hwi_restore()  // module-wide

Globally restore interrupts

C synopsis target-domain
macro Void Hwi_restore(UInt key);
 
ARGUMENTS
key — enable/disable state to restore
DETAILS
Hwi_restore globally restores interrupts to the state determined by the key argument provided by a previous invocation of Hwi_disable.
A context switch may occur when calling Hwi_restore if Hwi_restore reenables interrupts and another Hwi occurred while interrupts were disabled.
Hwi_restore may be called from main(). However, since Hwi_enable cannot be called from main(), interrupts are always disabled in main(), and a call to Hwi_restore has no effect.
 
Hwi_restoreInterrupt()  // module-wide

Restore a specific interrupt's enabled/disabled state

C synopsis target-domain
Void Hwi_restoreInterrupt(UInt intNum, UInt key);
 
ARGUMENTS
intNum — interrupt number to restore
key — key returned from enableInt or disableInt
DETAILS
Restores a specific interrupt identified by an interrupt number. restoreInterrupt is generally used to restore an interrupt to its state before disableInterrupt or enableInterrupt was invoked
 
Hwi_startup()  // module-wide

Initially enable interrupts

C synopsis target-domain
Void Hwi_startup();
 
DETAILS
Called within BIOS_start
Module-Wide Built-Ins

C synopsis target-domain
Types_ModuleId Hwi_Module_id();
// Get this module's unique id
 
Bool Hwi_Module_startupDone();
// Test if this module has completed startup
 
IHeap_Handle Hwi_Module_heap();
// The heap from which this module allocates memory
 
Bool Hwi_Module_hasMask();
// Test whether this module has a diagnostics mask
 
Bits16 Hwi_Module_getMask();
// Returns the diagnostics mask for this module
 
Void Hwi_Module_setMask(Bits16 mask);
// Set the diagnostics mask for this module
Instance Object Types

C synopsis target-domain
typedef struct Hwi_Object Hwi_Object;
// Opaque internal representation of an instance object
 
typedef Hwi_Object *Hwi_Handle;
// Client reference to an instance object
 
typedef struct Hwi_Struct Hwi_Struct;
// Opaque client structure large enough to hold an instance object
 
Hwi_Handle Hwi_handle(Hwi_Struct *structP);
// Convert this instance structure pointer into an instance handle
 
Hwi_Struct *Hwi_struct(Hwi_Handle handle);
// Convert this instance handle into an instance structure pointer
Instance Config Parameters

C synopsis target-domain
typedef struct Hwi_Params {
// Instance config-params structure
    IInstance_Params *instance;
    // Common per-instance configs
    UArg arg;
    // ISR function argument. Default is 0
    Bool enableInt;
    // Enable this interrupt when object is created? Default is true
    Int eventId;
    // Interrupt event ID (Interrupt Selection Number)
    IHwi_MaskingOption maskSetting;
    // maskSetting. Default is Hwi_MaskingOption_SELF
    Int priority;
    // Interrupt priority
} Hwi_Params;
 
Void Hwi_Params_init(Hwi_Params *params);
// Initialize this config-params structure with supplier-specified defaults before instance creation
 
config Hwi_Params.arg  // instance

ISR function argument. Default is 0

C synopsis target-domain
struct Hwi_Params {
      ...
    UArg arg;
 
 
config Hwi_Params.enableInt  // instance

Enable this interrupt when object is created? Default is true

C synopsis target-domain
struct Hwi_Params {
      ...
    Bool enableInt;
 
 
config Hwi_Params.eventId  // instance

Interrupt event ID (Interrupt Selection Number)

C synopsis target-domain
struct Hwi_Params {
      ...
    Int eventId;
 
DETAILS
Default is -1. Not all targets/devices support this instance parameter. On those that don't, this parameter is ignored.
 
config Hwi_Params.maskSetting  // instance

maskSetting. Default is Hwi_MaskingOption_SELF

C synopsis target-domain
struct Hwi_Params {
      ...
    IHwi_MaskingOption maskSetting;
 
 
config Hwi_Params.priority  // instance

Interrupt priority

C synopsis target-domain
struct Hwi_Params {
      ...
    Int priority;
 
DETAILS
The default value of -1 is used as a flag to indicate the lowest (logical) device-specific priority value.
Not all targets/devices support this instance parameter. On those that don't, this parameter is ignored.
Runtime Instance Creation

C synopsis target-domain
Hwi_Handle Hwi_create(Int intNum, Hwi_FuncPtr hwiFxn, const Hwi_Params *params, Error_Block *eb);
// Allocate and initialize a new instance object and return its handle
 
Void Hwi_construct(Hwi_Struct *structP, Int intNum, Hwi_FuncPtr hwiFxn, const Hwi_Params *params, Error_Block *eb);
// Initialize a new instance object inside the provided structure
ARGUMENTS
intNum — interrupt number
hwiFxn — pointer to ISR function
params — per-instance config params, or NULL to select default values (target-domain only)
eb — active error-handling block, or NULL to select default policy (target-domain only)
DETAILS
To cause a C function to run in response to a particular system interrupt, you create a Hwi object that encapsulates information regarding the interrupt required by the Hwi module.
The standard static and dynamic forms of the "create" function are supported by the ti.sysbios.hal.Hwi module. The following C code configures interrupt 5 with the "myIsr" C function.
  #include <ti/sysbios/hal/Hwi>

  Hwi_create(5, myIsr, NULL, NULL);
The NULL, NULL arguments are used when the default instance parameters and generic error handling is satisfactory for creating a Hwi object.
A Hwi dispatcher table entry is created and filled with the function specified by the fxn parameter and the attributes specified by the params parameter.
If params is NULL, the Hwi's dispatcher properties are assigned a default set of values. Otherwise, the following properties are specified by a structure of type Hwi_Params.
  • The arg element is a generic argument that is passed to the plugged function as its only parameter. The default value is 0.
  • The enableInt element determines whether the interrupt should be enabled in the IER by create.
  • The maskSetting element defines the dispatcherAutoNestingSupport behavior of the interrupt.
Hwi_create returns a pointer to the created Hwi object.
Instance Deletion

C synopsis target-domain
Void Hwi_delete(Hwi_Handle *handleP);
// Finalize and free this previously allocated instance object, setting the referenced handle to NULL
 
Void Hwi_destruct(Hwi_Struct *structP);
// Finalize the instance object inside the provided structure
 
Hwi_getFunc()  // instance

Get Hwi function and arg

C synopsis target-domain
IHwi_FuncPtr Hwi_getFunc(Hwi_Handle handle, UArg *arg);
 
ARGUMENTS
handle — handle of a previously-created Hwi instance object
arg — pointer for returning hwi's ISR function argument
RETURNS
hwi's ISR function
 
Hwi_getHookContext()  // instance

Get hook instance's context for a Hwi

C synopsis target-domain
Ptr Hwi_getHookContext(Hwi_Handle handle, Int id);
 
ARGUMENTS
handle — handle of a previously-created Hwi instance object
RETURNS
hook instance's context for hwi
hook instance's context for hwi
DETAILS
The Handle passed to this API must be the handle passed to any of the Hook functions, not the one returned by Hwi_create.
 
Hwi_getIrp()  // instance

Get address of interrupted instruction

C synopsis target-domain
IHwi_Irp Hwi_getIrp(Hwi_Handle handle);
 
ARGUMENTS
handle — handle of a previously-created Hwi instance object
RETURNS
most current IRP of a Hwi
 
Hwi_setFunc()  // instance

Overwrite Hwi function and arg

C synopsis target-domain
Void Hwi_setFunc(Hwi_Handle handle, IHwi_FuncPtr fxn, UArg arg);
 
ARGUMENTS
handle — handle of a previously-created Hwi instance object
fxn — pointer to ISR function
arg — argument to ISR function
DETAILS
Replaces a Hwi object's hwiFxn function originally provided in create.
 
Hwi_setHookContext()  // instance

Set hook instance's context for a Hwi

C synopsis target-domain
Void Hwi_setHookContext(Hwi_Handle handle, Int id, Ptr hookContext);
 
ARGUMENTS
handle — handle of a previously-created Hwi instance object
id — hook instance's ID
hook instance's ID
hookContext — value to write to context
value to write to context
DETAILS
The Handle passed to this API must be the handle passed to any of the Hook functions, not the one returned by Hwi_create.
Instance Convertors

C synopsis target-domain
IHwi_Handle Hwi_Handle_upCast(Hwi_Handle handle);
// unconditionally move one level up the inheritance hierarchy
 
Hwi_Handle Hwi_Handle_downCast(IHwi_Handle handle);
// conditionally move one level down the inheritance hierarchy; NULL upon failure
Instance Built-Ins

C synopsis target-domain
Int Hwi_Object_count();
// The number of statically-created instance objects
 
Hwi_Handle Hwi_Object_get(Hwi_Object *array, Int i);
// The handle of the i-th statically-created instance object (array == NULL)
 
Hwi_Handle Hwi_Object_first();
// The handle of the first dynamically-created instance object, or NULL
 
Hwi_Handle Hwi_Object_next(Hwi_Handle handle);
// The handle of the next dynamically-created instance object, or NULL
 
IHeap_Handle Hwi_Object_heap();
// The heap used to allocate dynamically-created instance objects
 
Types_Label *Hwi_Handle_label(Hwi_Handle handle, Types_Label *buf);
// The label associated with this instance object
 
String Hwi_Handle_name(Hwi_Handle handle);
// The name of this instance object
 
Configuration settings sourced in ti/sysbios/hal/Hwi.xdc
var Hwi = xdc.useModule('ti.sysbios.hal.Hwi');
module-wide constants & types
        const Hwi.MaskingOption_NONE;
        const Hwi.MaskingOption_ALL;
        const Hwi.MaskingOption_SELF;
        const Hwi.MaskingOption_BITMASK;
        const Hwi.MaskingOption_LOWER;
 
        obj.registerFxn = Void(*)(Int)  ...
        obj.createFxn = Void(*)(IHwi.Handle,Error.Block*)  ...
        obj.beginFxn = Void(*)(IHwi.Handle)  ...
        obj.endFxn = Void(*)(IHwi.Handle)  ...
        obj.deleteFxn = Void(*)(IHwi.Handle)  ...
 
        obj.hwiStackPeak = SizeT  ...
        obj.hwiStackSize = SizeT  ...
        obj.hwiStackBase = Ptr  ...
module-wide config parameters
        msg: "E_stackOverflow: ISR stack overflow."
    };
 
module-wide functions
per-instance config parameters
    var params = new Hwi.Params// Instance config-params object;
        params.arg// ISR function argument. Default is 0 = UArg 0;
        params.priority// Interrupt priority = Int -1;
per-instance creation
    var inst = Hwi.create// Create an instance-object(Int intNum, Void(*)(UArg) hwiFxn, params);
 
 
enum Hwi.MaskingOption

Shorthand interrupt masking options

Configuration settings
values of type Hwi.MaskingOption
    const Hwi.MaskingOption_NONE;
    const Hwi.MaskingOption_ALL;
    const Hwi.MaskingOption_SELF;
    const Hwi.MaskingOption_BITMASK;
    const Hwi.MaskingOption_LOWER;
 
VALUES
MaskingOption_NONE — No interrupts are disabled
MaskingOption_ALL — All interrupts are disabled
MaskingOption_SELF — Only this interrupt is disabled
MaskingOption_BITMASK — User supplies interrupt enable masks
MaskingOption_LOWER — All current and lower priority interrupts are disabled.
Only a few targets/devices truly support this masking option. For those that don't, this setting is treated the same as MaskingOption_SELF.
C SYNOPSIS
 
struct Hwi.HookSet

Hwi hook set type definition

Configuration settings
var obj = new Hwi.HookSet;
 
    obj.registerFxn = Void(*)(Int)  ...
    obj.createFxn = Void(*)(IHwi.Handle,Error.Block*)  ...
    obj.beginFxn = Void(*)(IHwi.Handle)  ...
    obj.endFxn = Void(*)(IHwi.Handle)  ...
    obj.deleteFxn = Void(*)(IHwi.Handle)  ...
 
DETAILS
The functions that make up a hookSet have certain restrictions. They cannot call any Hwi instance functions other than Hwi_getHookContext() and Hwi_setHookContext(). For all practical purposes, they should treat the Hwi_Handle passed to these functions as an opaque handle.
C SYNOPSIS
 
struct Hwi.StackInfo

Structure contains Hwi stack usage info

Configuration settings
var obj = new Hwi.StackInfo;
 
    obj.hwiStackPeak = SizeT  ...
    obj.hwiStackSize = SizeT  ...
    obj.hwiStackBase = Ptr  ...
 
DETAILS
Used by getStackInfo() and viewGetStackInfo() functions
C SYNOPSIS
 
config Hwi.E_stackOverflow  // module-wide

Error raised when a stack overflow (or corruption) is detected

Configuration settings
Hwi.E_stackOverflow = Error.Desc {
    msg: "E_stackOverflow: ISR stack overflow."
};
 
DETAILS
This error is raised by kernel's stack checking function. This function checks the stacks before every task switch to make sure that reserved word at top of stack has not been modified.
The stack checking logic is enabled by the checkStackFlag configuration parameter. If this flag is set to true, the kernel will validate the stacks.
C SYNOPSIS
 
config Hwi.dispatcherAutoNestingSupport  // module-wide

Include interrupt nesting logic in interrupt dispatcher?

Configuration settings
Hwi.dispatcherAutoNestingSupport = Bool true;
 
DETAILS
Default is true.
This option provides the user with the ability to optimize interrupt dispatcher performance when support for interrupt nesting is not required.
Setting this parameter to false will disable the logic in the interrupt dispatcher that manipulates interrupt mask registers and enables and disables interrupts before and after invoking the user's Hwi function.
Set this parameter to false if you don't need interrupts enabled during the execution of your Hwi functions.
C SYNOPSIS
 
config Hwi.dispatcherIrpTrackingSupport  // module-wide

Controls whether the dispatcher retains the interrupted thread's return address

Configuration settings
Hwi.dispatcherIrpTrackingSupport = Bool true;
 
DETAILS
This option is enabled by default.
Setting this parameter to false will disable the logic in the interrupt dispatcher that keeps track of the interrupt's return address and provide a small savings in interrupt latency.
The application can get an interrupt's most recent return address using the getIrp API.
C SYNOPSIS
 
config Hwi.dispatcherSwiSupport  // module-wide

Include Swi scheduling logic in interrupt dispatcher?

Configuration settings
Hwi.dispatcherSwiSupport = Bool undefined;
 
DETAILS
Default is inherited from BIOS.swiEnabled, which is true by default.
This option provides the user with the ability to optimize interrupt dispatcher performance when it is known that Swis will not be posted from any of their Hwi threads.
WARNING
Setting this parameter to false will disable the logic in the interrupt dispatcher that invokes the Swi scheduler prior to returning from an interrupt. With this setting, Swis MUST NOT be posted from Hwi functions!
C SYNOPSIS
 
config Hwi.dispatcherTaskSupport  // module-wide

Include Task scheduling logic in interrupt dispatcher?

Configuration settings
Hwi.dispatcherTaskSupport = Bool undefined;
 
DETAILS
Default is inherited from BIOS.taskEnabled, which is true by default.
This option provides the user with the ability to optimize interrupt dispatcher performance when it is known that no Task scheduling APIs (ie Semaphore_post()) will be executed from any of their Hwi threads.
Setting this parameter to false will disable the logic in the interrupt dispatcher that invokes the Task scheduler prior to returning from an interrupt.
C SYNOPSIS
 
metaonly config Hwi.checkStackFlag  // module-wide

Check for Hwi stack overrun during Idle loop

Configuration settings
Hwi.checkStackFlag = Bool true;
 
DETAILS
If true, then an idle function is added to the idle loop that checks for a Hwi stack overrun condition and raises an Error if one is detected.
The check consists of testing the top of stack value against its initial value (see initStackFlag). If it is no longer at this value, the assumption is that the ISR stack has been overrun. If the test fails, then the E_stackOverflow error is raised.
Runtime stack depth computation is only performed if initStackFlag is also true.
Default is true. (see initStackFlag).
To enable or disable full stack checking, you should set both this flag and the ti.sysbios.knl.Task.checkStackFlag.
 
metaonly config Hwi.common$  // module-wide

Common module configuration parameters

Configuration settings
Hwi.common$ = Types.Common$ undefined;
 
DETAILS
All modules have this configuration parameter. Its name contains the '$' character to ensure it does not conflict with configuration parameters declared by the module. This allows new configuration parameters to be added in the future without any chance of breaking existing modules.
 
metaonly config Hwi.initStackFlag  // module-wide

Initialize ISR stack with known value for stack checking at runtime

Configuration settings
Hwi.initStackFlag = Bool true;
 
DETAILS
This is also useful for inspection of stack in debugger or core dump utilities for stack overflow and depth.
Default is true. (see checkStackFlag).
 
metaonly Hwi.addHookSet()  // module-wide

addHookSet is used in a config file to add a hook set (defined by struct HookSet)

Configuration settings
Hwi.addHookSet(IHwi.HookSet hook) returns Void
 
ARGUMENTS
hook — structure of type HookSet
DETAILS
HookSet structure elements may be omitted, in which case those elements will not exist.
Instance Config Parameters

Configuration settings
var params = new Hwi.Params;
// Instance config-params object
    params.arg = UArg 0;
    // ISR function argument. Default is 0
    params.enableInt = Bool true;
    // Enable this interrupt when object is created? Default is true
    params.eventId = Int -1;
    // Interrupt event ID (Interrupt Selection Number)
    params.maskSetting = IHwi.MaskingOption IHwi.MaskingOption_SELF;
    // maskSetting. Default is Hwi_MaskingOption_SELF
    params.priority = Int -1;
    // Interrupt priority
 
config Hwi.Params.arg  // instance

ISR function argument. Default is 0

Configuration settings
var params = new Hwi.Params;
  ...
params.arg = UArg 0;
 
C SYNOPSIS
 
config Hwi.Params.enableInt  // instance

Enable this interrupt when object is created? Default is true

Configuration settings
var params = new Hwi.Params;
  ...
params.enableInt = Bool true;
 
C SYNOPSIS
 
config Hwi.Params.eventId  // instance

Interrupt event ID (Interrupt Selection Number)

Configuration settings
var params = new Hwi.Params;
  ...
params.eventId = Int -1;
 
DETAILS
Default is -1. Not all targets/devices support this instance parameter. On those that don't, this parameter is ignored.
C SYNOPSIS
 
config Hwi.Params.maskSetting  // instance

maskSetting. Default is Hwi_MaskingOption_SELF

Configuration settings
var params = new Hwi.Params;
  ...
 
C SYNOPSIS
 
config Hwi.Params.priority  // instance

Interrupt priority

Configuration settings
var params = new Hwi.Params;
  ...
params.priority = Int -1;
 
DETAILS
The default value of -1 is used as a flag to indicate the lowest (logical) device-specific priority value.
Not all targets/devices support this instance parameter. On those that don't, this parameter is ignored.
C SYNOPSIS
Static Instance Creation

Configuration settings
var params = new Hwi.Params;
// Allocate instance config-params
params.config =   ...
// Assign individual configs
 
var inst = Hwi.create(Int intNum, Void(*)(UArg) hwiFxn, params);
// Create an instance-object
ARGUMENTS
intNum — interrupt number
hwiFxn — pointer to ISR function
params — per-instance config params, or NULL to select default values (target-domain only)
eb — active error-handling block, or NULL to select default policy (target-domain only)
DETAILS
To cause a C function to run in response to a particular system interrupt, you create a Hwi object that encapsulates information regarding the interrupt required by the Hwi module.
The standard static and dynamic forms of the "create" function are supported by the ti.sysbios.hal.Hwi module. The following C code configures interrupt 5 with the "myIsr" C function.
  #include <ti/sysbios/hal/Hwi>

  Hwi_create(5, myIsr, NULL, NULL);
The NULL, NULL arguments are used when the default instance parameters and generic error handling is satisfactory for creating a Hwi object.
A Hwi dispatcher table entry is created and filled with the function specified by the fxn parameter and the attributes specified by the params parameter.
If params is NULL, the Hwi's dispatcher properties are assigned a default set of values. Otherwise, the following properties are specified by a structure of type Hwi_Params.
  • The arg element is a generic argument that is passed to the plugged function as its only parameter. The default value is 0.
  • The enableInt element determines whether the interrupt should be enabled in the IER by create.
  • The maskSetting element defines the dispatcherAutoNestingSupport behavior of the interrupt.
Hwi_create returns a pointer to the created Hwi object.
generated on Tue, 14 Feb 2017 19:58:47 GMT