Add dummy PIC IRQ support for Simple Vectored Architectures

The current implementation assumes that the architecture supports the Programmable
Interrupt Controller interrupt API in RTEMS. Most architectures do not use this
model and provide only the Simple Vectored interrupt API. The SPARC port has an
implementation of the PIC API that builds on the Simple Vectored API.

The code added here is just enough to compile. The hope is that a generic
PIC API wrapper will be implemented on top of the Simple Vectored which will
instantly provide support for all other architectures.

For now, the issues of code portability related to PCI support, in_cksum,
cpufunc.h, linkcmds etc are sufficiently challenging that just ensuring we are
able to compile for all RTEMS supported architectures will let us address many
issues.

In summary, this is just a placeholder which lets the RTEMS LibBSD code compile
on Simple Vectored architectures.

3 files changed, 402 insertions, 0 deletions

diff --git a/rtems-dummy-pic-irq/include/bsp/irq-generic.h b/rtems-dummy-pic-irq/include/bsp/irq-generic.h
new file mode 100644
index 00000000..d7d5cd09
--- /dev/null
+++ b/rtems-dummy-pic-irq/include/bsp/irq-generic.h
@@ -0,0 +1,252 @@
+/**
+ * @file
+ *
+ * @ingroup bsp_interrupt
+ *
+ * @brief Generic BSP interrupt support API.
+ */
+
+/*
+ * Based on concepts of Pavel Pisa, Till Straumann and Eric Valette.
+ *
+ * Copyright (c) 2008, 2009, 2010
+ * 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.
+ */
+
+#ifndef LIBBSP_SHARED_IRQ_GENERIC_H
+#define LIBBSP_SHARED_IRQ_GENERIC_H
+
+#include <stdbool.h>
+
+#include <rtems/irq-extension.h>
+
+#include <bsp/irq.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+#if !defined(BSP_INTERRUPT_VECTOR_MIN) || !defined(BSP_INTERRUPT_VECTOR_MAX) || (BSP_INTERRUPT_VECTOR_MAX + 1) < BSP_INTERRUPT_VECTOR_MIN
+  #error "invalid BSP_INTERRUPT_VECTOR_MIN or BSP_INTERRUPT_VECTOR_MAX"
+#endif
+
+#if defined(BSP_INTERRUPT_USE_INDEX_TABLE) && !defined(BSP_INTERRUPT_HANDLER_TABLE_SIZE)
+  #error "if you define BSP_INTERRUPT_USE_INDEX_TABLE, you have to define BSP_INTERRUPT_HANDLER_TABLE_SIZE etc. as well"
+#endif
+
+#if defined(BSP_INTERRUPT_NO_HEAP_USAGE) && !defined(BSP_INTERRUPT_USE_INDEX_TABLE)
+  #error "if you define BSP_INTERRUPT_NO_HEAP_USAGE, you have to define BSP_INTERRUPT_USE_INDEX_TABLE etc. as well"
+#endif
+
+#define BSP_INTERRUPT_VECTOR_NUMBER \
+  (BSP_INTERRUPT_VECTOR_MAX - BSP_INTERRUPT_VECTOR_MIN + 1)
+
+#ifndef BSP_INTERRUPT_HANDLER_TABLE_SIZE
+  #define BSP_INTERRUPT_HANDLER_TABLE_SIZE BSP_INTERRUPT_VECTOR_NUMBER
+#endif
+
+struct bsp_interrupt_handler_entry {
+  rtems_interrupt_handler handler;
+  void *arg;
+  const char *info;
+  struct bsp_interrupt_handler_entry *next;
+};
+
+typedef struct bsp_interrupt_handler_entry bsp_interrupt_handler_entry;
+
+extern bsp_interrupt_handler_entry bsp_interrupt_handler_table [];
+
+#ifdef BSP_INTERRUPT_USE_INDEX_TABLE
+  #if BSP_INTERRUPT_HANDLER_TABLE_SIZE < 0x100
+    typedef uint8_t bsp_interrupt_handler_index_type;
+  #elif BSP_INTERRUPT_HANDLER_TABLE_SIZE < 0x10000
+    typedef uint16_t bsp_interrupt_handler_index_type;
+  #else
+    typedef uint32_t bsp_interrupt_handler_index_type;
+  #endif
+  extern bsp_interrupt_handler_index_type bsp_interrupt_handler_index_table [];
+#endif
+
+static inline rtems_vector_number bsp_interrupt_handler_index(
+  rtems_vector_number vector
+)
+{
+  #ifdef BSP_INTERRUPT_USE_INDEX_TABLE
+    return bsp_interrupt_handler_index_table [vector - BSP_INTERRUPT_VECTOR_MIN];
+  #else
+    return vector - BSP_INTERRUPT_VECTOR_MIN;
+  #endif
+}
+
+/**
+ * @defgroup bsp_interrupt BSP Interrupt Support
+ *
+ * @ingroup rtems_interrupt_extension
+ *
+ * The BSP interrupt support manages a sequence of interrupt vector numbers
+ * ranging from @ref BSP_INTERRUPT_VECTOR_MIN to @ref BSP_INTERRUPT_VECTOR_MAX
+ * including the end points.  It provides methods to
+ * @ref bsp_interrupt_handler_install() "install",
+ * @ref bsp_interrupt_handler_remove() "remove" and
+ * @ref bsp_interrupt_handler_dispatch() "dispatch" interrupt handlers for each
+ * vector number.  It implements parts of the RTEMS interrupt manager.
+ *
+ * The entry points to a list of interrupt handlers are stored in a table
+ * (= handler table).
+ *
+ * You have to configure the BSP interrupt support in the <bsp/irq.h> file
+ * for each BSP.  For a minimum configuration you have to provide
+ * @ref BSP_INTERRUPT_VECTOR_MIN and @ref BSP_INTERRUPT_VECTOR_MAX.
+ *
+ * For boards with small memory requirements you can define
+ * @ref BSP_INTERRUPT_USE_INDEX_TABLE.  With an enabled index table the handler
+ * table will be accessed via a small index table.  You can define the size of
+ * the handler table with @ref BSP_INTERRUPT_HANDLER_TABLE_SIZE.
+ *
+ * Normally new list entries are allocated from the heap.  You may define
+ * @ref BSP_INTERRUPT_NO_HEAP_USAGE, if you do not want to use the heap.  For
+ * this option you have to define @ref BSP_INTERRUPT_USE_INDEX_TABLE as well.
+ *
+ * You have to provide some special routines in your BSP (follow the links for
+ * the details):
+ * - bsp_interrupt_facility_initialize()
+ * - bsp_interrupt_vector_enable()
+ * - bsp_interrupt_vector_disable()
+ * - bsp_interrupt_handler_default()
+ *
+ * The following now deprecated functions are provided for backward
+ * compatibility:
+ * - BSP_get_current_rtems_irq_handler()
+ * - BSP_install_rtems_irq_handler()
+ * - BSP_install_rtems_shared_irq_handler()
+ * - BSP_remove_rtems_irq_handler()
+ * - BSP_rtems_irq_mngt_set()
+ * - BSP_rtems_irq_mngt_get()
+ *
+ * @{
+ */
+
+#ifdef BSP_INTERRUPT_CUSTOM_VALID_VECTOR
+  bool bsp_interrupt_is_valid_vector(rtems_vector_number vector);
+#else
+  /**
+   * @brief Returns true if the interrupt vector with number @a vector is
+   * valid.
+   */
+  static inline bool bsp_interrupt_is_valid_vector(rtems_vector_number vector)
+  {
+    return (rtems_vector_number) BSP_INTERRUPT_VECTOR_MIN <= vector
+      && vector <= (rtems_vector_number) BSP_INTERRUPT_VECTOR_MAX;
+  }
+#endif
+
+/**
+ * @brief Default interrupt handler.
+ *
+ * This routine will be called from bsp_interrupt_handler_dispatch() with the
+ * current vector number @a vector when the handler list for this vector is
+ * empty or the vector number is out of range.
+ *
+ * @note This function must cope with arbitrary vector numbers @a vector.
+ */
+void bsp_interrupt_handler_default(rtems_vector_number vector);
+
+/**
+ * @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);
+
+/**
+ * @brief BSP specific initialization.
+ *
+ * This routine will be called form bsp_interrupt_initialize() and shall do the
+ * following:
+ * - Initialize the facilities that call bsp_interrupt_handler_dispatch().  For
+ * example on PowerPC the external exception handler.
+ * - Initialize the interrupt controller.  You shall set the interrupt
+ * controller in a state such that interrupts are disabled for all vectors.
+ * The vectors will be enabled with your bsp_interrupt_vector_enable() function
+ * and disabled via your bsp_interrupt_vector_disable() function.  These
+ * functions have to work afterwards.
+ *
+ * @return On success RTEMS_SUCCESSFUL shall be returned.
+ */
+rtems_status_code bsp_interrupt_facility_initialize(void);
+
+/**
+ * @brief Enables the interrupt vector with number @a vector.
+ *
+ * This function shall enable the vector at the corresponding facility (in most
+ * cases the interrupt controller).  It will be called then the first handler
+ * is installed for the vector in bsp_interrupt_handler_install().  It is
+ * guaranteed that the vector number is within the BSP_INTERRUPT_VECTOR_MIN and
+ * BSP_INTERRUPT_VECTOR_MAX range.
+ *
+ * @note You must not install or remove an interrupt handler in this function.
+ * This may result in a deadlock.
+ *
+ * @return On success RTEMS_SUCCESSFUL shall be returned.
+ */
+rtems_status_code bsp_interrupt_vector_enable(rtems_vector_number vector);
+
+/**
+ * @brief Disables the interrupt vector with number @a vector.
+ *
+ * This function shall disable the vector at the corresponding facility (in
+ * most cases the interrupt controller).  It will be called then the last
+ * handler is removed for the vector in bsp_interrupt_handler_remove().  It is
+ * guaranteed that the vector number is within the BSP_INTERRUPT_VECTOR_MIN and
+ * BSP_INTERRUPT_VECTOR_MAX range.
+ *
+ * @note You must not install or remove an interrupt handler in this function.
+ * This may result in a deadlock.
+ *
+ * @return On success RTEMS_SUCCESSFUL shall be returned.
+ */
+rtems_status_code bsp_interrupt_vector_disable(rtems_vector_number vector);
+
+/**
+ * @brief Sequencially calls all interrupt handlers for the vector number @a
+ * vector.
+ *
+ * If the vector number is out of range or the handler list is empty
+ * bsp_interrupt_handler_default() will be called with argument @a vector.
+ *
+ * You can call this function within every context which can be disabled via
+ * rtems_interrupt_disable().
+ */
+static inline void bsp_interrupt_handler_dispatch(rtems_vector_number vector)
+{
+  if (bsp_interrupt_is_valid_vector(vector)) {
+    bsp_interrupt_handler_entry *e =
+      &bsp_interrupt_handler_table [bsp_interrupt_handler_index(vector)];
+
+    do {
+      (*e->handler)(e->arg);
+      e = e->next;
+    } while (e != NULL);
+  } else {
+    bsp_interrupt_handler_default(vector);
+  }
+}
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* LIBBSP_SHARED_IRQ_GENERIC_H */
diff --git a/rtems-dummy-pic-irq/include/bsp/irq-info.h b/rtems-dummy-pic-irq/include/bsp/irq-info.h
new file mode 100644
index 00000000..02efc955
--- /dev/null
+++ b/rtems-dummy-pic-irq/include/bsp/irq-info.h
@@ -0,0 +1,65 @@
+/**
+ * @file
+ *
+ * @ingroup bsp_interrupt
+ *
+ * @brief Generic BSP interrupt information API.
+ */
+
+/*
+ * Copyright (c) 2008, 2009
+ * 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.
+ */
+
+#ifndef LIBBSP_SHARED_IRQ_INFO_H
+#define LIBBSP_SHARED_IRQ_INFO_H
+
+#include <rtems/shell.h>
+#include <rtems/bspIo.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/**
+ * @defgroup bsp_interrupt BSP Interrupt Information
+ *
+ * @ingroup rtems_interrupt_extension
+ *
+ * @{
+ */
+
+/**
+ * @brief Prints interrupt information via the printk plugin @a print with the
+ * context @a context.
+ */
+void bsp_interrupt_report_with_plugin(
+  void *context,
+  rtems_printk_plugin_t print
+);
+
+/**
+ * @brief Prints interrupt information via the default printk plugin.
+ */
+void bsp_interrupt_report(void);
+
+/**
+ * @brief Shell command entry for interrupt information.
+ */
+extern struct rtems_shell_cmd_tt bsp_interrupt_shell_command;
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* LIBBSP_SHARED_IRQ_INFO_H */
diff --git a/rtems-dummy-pic-irq/include/bsp/irq.h b/rtems-dummy-pic-irq/include/bsp/irq.h
new file mode 100644
index 00000000..19aed6fd
--- /dev/null
+++ b/rtems-dummy-pic-irq/include/bsp/irq.h
@@ -0,0 +1,85 @@
+/**
+ * @file
+ *
+ * @ingroup bsp_interrupt
+ *
+ * @brief BSP interrupt support configuration template.
+ */
+
+/*
+ * Based on concepts of Pavel Pisa, Till Straumann and Eric Valette.
+ *
+ * Copyright (c) 2008, 2009, 2010
+ * 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.
+ */
+
+#ifndef LIBBSP_SHARED_IRQ_CONFIG_H
+#define LIBBSP_SHARED_IRQ_CONFIG_H
+
+#include <stdint.h>
+
+/**
+ * @addtogroup bsp_interrupt
+ *
+ * @{
+ */
+
+/**
+ * @brief Minimum vector number.
+ */
+#define BSP_INTERRUPT_VECTOR_MIN 0
+
+/**
+ * @brief Maximum vector number.
+ */
+#define BSP_INTERRUPT_VECTOR_MAX 0
+
+/**
+ * @brief Enables the index table.
+ *
+ * If you enable the index table, you have to define a size for the handler
+ * table (@ref BSP_INTERRUPT_HANDLER_TABLE_SIZE) and must provide an integer
+ * type capable to index the complete handler table (@ref
+ * bsp_interrupt_handler_index_type).
+ */
+#undef BSP_INTERRUPT_USE_INDEX_TABLE
+
+/**
+ * @brief Disables usage of the heap.
+ *
+ * If you define this, you have to define @ref BSP_INTERRUPT_USE_INDEX_TABLE as
+ * well.
+ */
+#undef BSP_INTERRUPT_NO_HEAP_USAGE
+
+#ifdef BSP_INTERRUPT_USE_INDEX_TABLE
+  /**
+   * @brief Size of the handler table.
+   */
+  #define BSP_INTERRUPT_HANDLER_TABLE_SIZE 0
+
+  /**
+   * @brief Integer type capable to index the complete handler table.
+   */
+  typedef uint8_t bsp_interrupt_handler_index_type;
+#endif
+
+/**
+ * @brief Enable custom vector checking
+ *
+ * If defined the BSP must implement the custom bsp_interrupt_is_valid_vector()
+ * vector validator check routine.
+ */
+#undef BSP_INTERRUPT_CUSTOM_VALID_VECTOR
+
+/** @} */
+
+#endif /* LIBBSP_SHARED_IRQ_CONFIG_H */