/**
* @file
*
* @ingroup bsp_interrupt
*
* @brief Source file for generic BSP interrupt support.
*/
/*
* Based on concepts of Pavel Pisa, Till Straumann and Eric Valette.
*
* Copyright (c) 2008
* Embedded Brains GmbH
* Obere Lagerstr. 30
* D-82178 Puchheim
* Germany
* rtems@embedded-brains.de
*
* The license and distribution terms for this file may be found in the file
* LICENSE in this distribution or at http://www.rtems.com/license/LICENSE.
*/
#include <bsp/irq-generic.h>
#ifdef BSP_INTERRUPT_USE_INDEX_TABLE
bsp_interrupt_handler_index_type bsp_interrupt_handler_index_table [BSP_INTERRUPT_VECTOR_NUMBER];
#endif /* BSP_INTERRUPT_USE_INDEX_TABLE */
static void bsp_interrupt_handler_empty( rtems_vector_number vector, void *arg)
{
bsp_interrupt_handler_default( vector);
}
bsp_interrupt_handler_entry bsp_interrupt_handler_table [BSP_INTERRUPT_HANDLER_TABLE_SIZE] = {
[0 ... BSP_INTERRUPT_HANDLER_TABLE_SIZE - 1] = {
.handler = bsp_interrupt_handler_empty,
.arg = NULL,
.info = NULL,
.next = NULL
}
};
/* The last entry indicates if everything is initialized */
static uint8_t bsp_interrupt_handler_unique_table [(BSP_INTERRUPT_HANDLER_TABLE_SIZE + 7 + 1) / 8];
static rtems_id bsp_interrupt_mutex = RTEMS_ID_NONE;
static inline bool bsp_interrupt_is_handler_unique( rtems_vector_number index)
{
rtems_vector_number i = index / 8;
rtems_vector_number s = index % 8;
return (bsp_interrupt_handler_unique_table [i] >> s) & 0x1;
}
static inline void bsp_interrupt_set_handler_unique( rtems_vector_number index, bool unique)
{
rtems_vector_number i = index / 8;
rtems_vector_number s = index % 8;
if (unique) {
bsp_interrupt_handler_unique_table [i] |= (uint8_t) (0x1U << s);
} else {
bsp_interrupt_handler_unique_table [i] &= (uint8_t) ~(0x1U << s);
}
}
static inline bool bsp_interrupt_is_initialized(void)
{
return bsp_interrupt_is_handler_unique( BSP_INTERRUPT_HANDLER_TABLE_SIZE);
}
static inline void bsp_interrupt_set_initialized(void)
{
bsp_interrupt_set_handler_unique( BSP_INTERRUPT_HANDLER_TABLE_SIZE, true);
}
static inline bool bsp_interrupt_is_empty_handler_entry( bsp_interrupt_handler_entry *e)
{
return e->handler == bsp_interrupt_handler_empty;
}
static inline void bsp_interrupt_clear_handler_entry( bsp_interrupt_handler_entry *e)
{
e->handler = bsp_interrupt_handler_empty;
e->arg = NULL;
e->info = NULL;
e->next = NULL;
}
static inline bool bsp_interrupt_allocate_handler_index( rtems_vector_number vector, rtems_vector_number *index)
{
#ifdef BSP_INTERRUPT_USE_INDEX_TABLE
rtems_vector_number i = 0;
/* The first entry will remain empty */
for (i = 1; i < BSP_INTERRUPT_HANDLER_TABLE_SIZE; ++i) {
if (bsp_interrupt_is_empty_handler_entry( &bsp_interrupt_handler_table [i])) {
*index = i;
return 1;
}
}
return 0;
#else /* BSP_INTERRUPT_USE_INDEX_TABLE */
*index = vector;
return 1;
#endif /* BSP_INTERRUPT_USE_INDEX_TABLE */
}
static bsp_interrupt_handler_entry *bsp_interrupt_allocate_handler_entry( void)
{
#ifdef BSP_INTERRUPT_NO_HEAP_USAGE
rtems_vector_number index = 0;
if (bsp_interrupt_allocate_handler_index( 0, &index)) {
return &bsp_interrupt_handler_table [index];
} else {
return NULL;
}
#else /* BSP_INTERRUPT_NO_HEAP_USAGE */
return malloc( sizeof( bsp_interrupt_handler_entry));
#endif /* BSP_INTERRUPT_NO_HEAP_USAGE */
}
static void bsp_interrupt_free_handler_entry( bsp_interrupt_handler_entry *e)
{
#ifdef BSP_INTERRUPT_NO_HEAP_USAGE
bsp_interrupt_clear_handler_entry( e);
#else /* BSP_INTERRUPT_NO_HEAP_USAGE */
free( e);
#endif /* BSP_INTERRUPT_NO_HEAP_USAGE */
}
static rtems_status_code bsp_interrupt_lock( void)
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
if (_System_state_Is_up( _System_state_Get())) {
if (bsp_interrupt_mutex == RTEMS_ID_NONE) {
rtems_id mutex = RTEMS_ID_NONE;
rtems_interrupt_level level;
/* Create a mutex */
sc = rtems_semaphore_create (
rtems_build_name( 'I', 'N', 'T', 'R'),
1,
RTEMS_SIMPLE_BINARY_SEMAPHORE | RTEMS_INHERIT_PRIORITY | RTEMS_PRIORITY,
RTEMS_NO_PRIORITY,
&mutex
);
if (sc != RTEMS_SUCCESSFUL) {
return sc;
}
/* Assign the mutex */
rtems_interrupt_disable( level);
if (bsp_interrupt_mutex == RTEMS_ID_NONE) {
/* Nobody else assigned the mutex in the meantime */
bsp_interrupt_mutex = mutex;
rtems_interrupt_enable( level);
} else {
/* Somebody else won */
rtems_interrupt_enable( level);
sc = rtems_semaphore_delete( mutex);
if (sc != RTEMS_SUCCESSFUL) {
return sc;
}
}
}
return rtems_semaphore_obtain( bsp_interrupt_mutex, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
} else {
return RTEMS_SUCCESSFUL;
}
}
static rtems_status_code bsp_interrupt_unlock( void)
{
if (bsp_interrupt_mutex != RTEMS_ID_NONE) {
return rtems_semaphore_release( bsp_interrupt_mutex);
} else {
return RTEMS_SUCCESSFUL;
}
}
/**
* @brief Initialize BSP interrupt support.
*
* You must call this function before you can install, remove and dispatch
* interrupt handlers. The BSP specific bsp_interrupt_facility_initialize()
* function will be called after all internals are initialized. Initialization
* is complete if everything was successful.
*/
rtems_status_code bsp_interrupt_initialize( void)
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
/* Lock */
sc = bsp_interrupt_lock();
if (sc != RTEMS_SUCCESSFUL) {
return sc;
}
/* Check if already initialized */
if (bsp_interrupt_is_initialized()) {
bsp_interrupt_unlock();
return RTEMS_INTERNAL_ERROR;
}
/* BSP specific initialization */
sc = bsp_interrupt_facility_initialize();
if (sc != RTEMS_SUCCESSFUL) {
bsp_interrupt_unlock();
return sc;
}
/* Now we are initialized */
bsp_interrupt_set_initialized();
/* Unlock */
sc = bsp_interrupt_unlock();
if (sc != RTEMS_SUCCESSFUL) {
return sc;
}
return RTEMS_SUCCESSFUL;
}
/**
* @brief Installs an interrupt handler.
*
* @ingroup bsp_interrupt
*
* @return In addition to the standard status codes this function returns:
* - If the BSP interrupt support is not initialized RTEMS_INTERNAL_ERROR will
* be returned.
* - If not enough memory for a new handler is available RTEMS_NO_MEMORY will
* be returned
*
* @see rtems_interrupt_handler_install()
*/
static rtems_status_code bsp_interrupt_handler_install( rtems_vector_number vector, const char *info, rtems_option options, rtems_interrupt_handler handler, void *arg)
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
rtems_interrupt_level level;
rtems_vector_number index = 0;
bsp_interrupt_handler_entry *head = NULL;
bsp_interrupt_handler_entry *tail = NULL;
bsp_interrupt_handler_entry *current = NULL;
bsp_interrupt_handler_entry *match = NULL;
bool enable_vector = false;
/* Check parameters and system state */
if (!bsp_interrupt_is_initialized()) {
return RTEMS_INTERNAL_ERROR;
} else if (!bsp_interrupt_is_valid_vector( vector)) {
return RTEMS_INVALID_NUMBER;
} else if (handler == NULL) {
return RTEMS_INVALID_ADDRESS;
} else if (rtems_interrupt_is_in_progress()) {
return RTEMS_CALLED_FROM_ISR;
}
/* Lock */
sc = bsp_interrupt_lock();
if (sc != RTEMS_SUCCESSFUL) {
return sc;
}
/* Get handler table index */
index = bsp_interrupt_handler_index( vector);
/* Get head entry of the handler list for current vector */
head = &bsp_interrupt_handler_table [index];
if (bsp_interrupt_is_empty_handler_entry( head)) {
/*
* No real handler installed yet. So allocate a new index in
* the handler table and fill the entry with life.
*/
if (bsp_interrupt_allocate_handler_index( vector, &index)) {
rtems_interrupt_disable( level);
bsp_interrupt_handler_table [index].handler = handler;
bsp_interrupt_handler_table [index].arg = arg;
#ifdef BSP_INTERRUPT_USE_INDEX_TABLE
bsp_interrupt_handler_index_table [vector] = index;
#endif /* BSP_INTERRUPT_USE_INDEX_TABLE */
rtems_interrupt_enable( level);
bsp_interrupt_handler_table [index].info = info;
} else {
/* Handler table is full */
bsp_interrupt_unlock();
return RTEMS_NO_MEMORY;
}
/* This is the first handler so enable the vector later */
enable_vector = true;
} else {
/* Ensure that a unique handler remains unique */
if (RTEMS_INTERRUPT_IS_UNIQUE( options) || bsp_interrupt_is_handler_unique( index)) {
/*
* Tried to install a unique handler on a not empty
* list or there is already a unique handler installed.
*/
bsp_interrupt_unlock();
return RTEMS_RESOURCE_IN_USE;
}
/*
* Search for the list tail and check if the handler is already
* installed.
*/
current = head;
do {
if (current->handler == handler && current->arg == arg) {
match = current;
}
tail = current;
current = current->next;
} while (current != NULL);
/* Ensure the handler is not already installed */
if (match != NULL) {
/* The handler is already installed */
bsp_interrupt_unlock();
return RTEMS_TOO_MANY;
}
/* Allocate a new entry */
current = bsp_interrupt_allocate_handler_entry();
if (current == NULL) {
/* Not enough memory */
bsp_interrupt_unlock();
return RTEMS_NO_MEMORY;
}
/* Set entry */
current->handler = handler;
current->arg = arg;
current->info = info;
current->next = NULL;
/* Link to list tail */
rtems_interrupt_disable( level);
tail->next = current;
rtems_interrupt_enable( level);
}
/* Make the handler unique if necessary */
bsp_interrupt_set_handler_unique( index, RTEMS_INTERRUPT_IS_UNIQUE( options));
/* Enable the vector if necessary */
if (enable_vector) {
sc = bsp_interrupt_vector_enable( vector);
if (sc != RTEMS_SUCCESSFUL) {
bsp_interrupt_unlock();
return sc;
}
}
/* Unlock */
sc = bsp_interrupt_unlock();
if (sc != RTEMS_SUCCESSFUL) {
return sc;
}
return RTEMS_SUCCESSFUL;
}
/**
* @brief Removes an interrupt handler.
*
* @ingroup bsp_interrupt
*
* @return In addition to the standard status codes this function returns
* RTEMS_INTERNAL_ERROR if the BSP interrupt support is not initialized.
*
* @see rtems_interrupt_handler_remove().
*/
static rtems_status_code bsp_interrupt_handler_remove( rtems_vector_number vector, rtems_interrupt_handler handler, void *arg)
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
rtems_interrupt_level level;
rtems_vector_number index = 0;
bsp_interrupt_handler_entry *head = NULL;
bsp_interrupt_handler_entry *current = NULL;
bsp_interrupt_handler_entry *previous = NULL;
bsp_interrupt_handler_entry *match = NULL;
/* Check parameters and system state */
if (!bsp_interrupt_is_initialized()) {
return RTEMS_INTERNAL_ERROR;
} else if (!bsp_interrupt_is_valid_vector( vector)) {
return RTEMS_INVALID_NUMBER;
} else if (handler == NULL) {
return RTEMS_INVALID_ADDRESS;
} else if (rtems_interrupt_is_in_progress()) {
return RTEMS_CALLED_FROM_ISR;
}
/* Lock */
sc = bsp_interrupt_lock();
if (sc != RTEMS_SUCCESSFUL) {
return sc;
}
/* Get handler table index */
index = bsp_interrupt_handler_index( vector);
/* Get head entry of the handler list for current vector */
head = &bsp_interrupt_handler_table [index];
/* Search for a matching entry */
current = head;
do {
if (current->handler == handler && current->arg == arg) {
match = current;
break;
}
previous = current;
current = current->next;
} while (current != NULL);
/* Remove the matching entry */
if (match != NULL) {
if (match->next != NULL) {
/*
* The match has a successor. A successor is always
* allocated. So replace the match with its successor
* and free the successor entry.
*/
current = match->next;
rtems_interrupt_disable( level);
*match = *current;
rtems_interrupt_enable( level);
bsp_interrupt_free_handler_entry( current);
} else if (match == head) {
/*
* The match is the list head and has no successor.
* The list head is stored in a static table so clear
* this entry. Since now the list is empty disable the
* vector.
*/
/* Disable the vector */
sc = bsp_interrupt_vector_disable( vector);
/* Clear entry */
rtems_interrupt_disable( level);
bsp_interrupt_clear_handler_entry( head);
#ifdef BSP_INTERRUPT_USE_INDEX_TABLE
bsp_interrupt_handler_index_table [vector] = 0;
#endif /* BSP_INTERRUPT_USE_INDEX_TABLE */
rtems_interrupt_enable( level);
/* Allow shared handlers */
bsp_interrupt_set_handler_unique( index, false);
/* Check status code */
if (sc != RTEMS_SUCCESSFUL) {
bsp_interrupt_unlock();
return sc;
}
} else {
/*
* The match is the list tail and has a predecessor.
* So terminate the predecessor and free the match.
*/
rtems_interrupt_disable( level);
previous->next = NULL;
rtems_interrupt_enable( level);
bsp_interrupt_free_handler_entry( match);
}
} else {
/* No matching entry found */
bsp_interrupt_unlock();
return RTEMS_UNSATISFIED;
}
/* Unlock */
sc = bsp_interrupt_unlock();
if (sc != RTEMS_SUCCESSFUL) {
return sc;
}
return RTEMS_SUCCESSFUL;
}
/**
* @brief Iterates over all installed interrupt handler of a vector.
*
* @ingroup bsp_interrupt
*
* @return In addition to the standard status codes this function returns
* RTEMS_INTERNAL_ERROR if the BSP interrupt support is not initialized.
*
* @see rtems_interrupt_handler_iterate().
*/
static rtems_status_code bsp_interrupt_handler_iterate( rtems_vector_number vector, rtems_interrupt_per_handler_routine routine, void *arg)
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
bsp_interrupt_handler_entry *current = NULL;
rtems_option options = 0;
rtems_vector_number index = 0;
/* Check parameters and system state */
if (!bsp_interrupt_is_initialized()) {
return RTEMS_INTERNAL_ERROR;
} else if (!bsp_interrupt_is_valid_vector( vector)) {
return RTEMS_INVALID_NUMBER;
} else if (rtems_interrupt_is_in_progress()) {
return RTEMS_CALLED_FROM_ISR;
}
/* Lock */
sc = bsp_interrupt_lock();
if (sc != RTEMS_SUCCESSFUL) {
return sc;
}
/* Interate */
index = bsp_interrupt_handler_index( vector);
current = &bsp_interrupt_handler_table [index];
if (!bsp_interrupt_is_empty_handler_entry( current)) {
do {
options = bsp_interrupt_is_handler_unique( index) ? RTEMS_INTERRUPT_UNIQUE : RTEMS_INTERRUPT_SHARED;
routine( arg, current->info, options, current->handler, current->arg);
current = current->next;
} while (current != NULL);
}
/* Unlock */
sc = bsp_interrupt_unlock();
if (sc != RTEMS_SUCCESSFUL) {
return sc;
}
return RTEMS_SUCCESSFUL;
}
rtems_status_code rtems_interrupt_handler_install( rtems_vector_number vector, const char *info, rtems_option options, rtems_interrupt_handler handler, void *arg)
{
return bsp_interrupt_handler_install( vector, info, options, handler, arg);
}
rtems_status_code rtems_interrupt_handler_remove( rtems_vector_number vector, rtems_interrupt_handler handler, void *arg)
{
return bsp_interrupt_handler_remove( vector, handler, arg);
}
rtems_status_code rtems_interrupt_handler_iterate( rtems_vector_number vector, rtems_interrupt_per_handler_routine routine, void *arg)
{
return bsp_interrupt_handler_iterate( vector, routine, arg);
}
