Diff: nordic/app_common/hci_mem_pool.c

Revision:

46:2bfbbe290083

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nordic/app_common/hci_mem_pool.c	Wed Jul 16 10:54:22 2014 +0100
@@ -0,0 +1,235 @@
+/* Copyright (c) 2013 Nordic Semiconductor. All Rights Reserved.
+ *
+ * The information contained herein is property of Nordic Semiconductor ASA.
+ * Terms and conditions of usage are described in detail in NORDIC
+ * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
+ *
+ * Licensees are granted free, non-transferable use of the information. NO
+ * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
+ * the file.
+ *
+ */
+ 
+#include "hci_mem_pool.h"
+#include "hci_mem_pool_internal.h"
+#include <stdbool.h>
+#include <stdio.h>
+
+/**@brief RX buffer element instance structure. 
+ */
+typedef struct 
+{
+    uint8_t  rx_buffer[RX_BUF_SIZE];                                /**< RX buffer memory array. */  
+    uint32_t length;                                                /**< Length of the RX buffer memory array. */
+} rx_buffer_elem_t;
+
+/**@brief RX buffer queue element instance structure. 
+ */
+typedef struct 
+{
+    rx_buffer_elem_t * p_buffer;                                    /**< Pointer to RX buffer element. */
+    uint32_t           free_window_count;                           /**< Free space element count. */
+    uint32_t           free_available_count;                        /**< Free area element count. */
+    uint32_t           read_available_count;                        /**< Read area element count. */
+    uint32_t           write_index;                                 /**< Write position index. */                                      
+    uint32_t           read_index;                                  /**< Read position index. */                                                                            
+    uint32_t           free_index;                                  /**< Free position index. */                                                                                                                  
+} rx_buffer_queue_t;
+
+static bool              m_is_tx_allocated;                         /**< Boolean value to determine if the TX buffer is allocated. */
+static rx_buffer_elem_t  m_rx_buffer_elem_queue[RX_BUF_QUEUE_SIZE]; /**< RX buffer element instances. */
+static rx_buffer_queue_t m_rx_buffer_queue;                         /**< RX buffer queue element instance. */
+
+
+uint32_t hci_mem_pool_open(void)
+{
+    m_is_tx_allocated                      = false;    
+    m_rx_buffer_queue.p_buffer             = m_rx_buffer_elem_queue;
+    m_rx_buffer_queue.free_window_count    = RX_BUF_QUEUE_SIZE;
+    m_rx_buffer_queue.free_available_count = 0;
+    m_rx_buffer_queue.read_available_count = 0;
+    m_rx_buffer_queue.write_index          = 0;    
+    m_rx_buffer_queue.read_index           = 0;        
+    m_rx_buffer_queue.free_index           = 0;            
+    
+    return NRF_SUCCESS;
+}
+
+
+uint32_t hci_mem_pool_close(void)
+{    
+    return NRF_SUCCESS;
+}
+
+
+uint32_t hci_mem_pool_tx_alloc(void ** pp_buffer)
+{
+    static uint8_t tx_buffer[TX_BUF_SIZE];  
+
+    uint32_t err_code;
+    
+    if (pp_buffer == NULL)
+    {
+        return NRF_ERROR_NULL;
+    }
+    
+    if (!m_is_tx_allocated)
+    {        
+            m_is_tx_allocated = true;
+            *pp_buffer        = tx_buffer;
+            err_code          = NRF_SUCCESS;
+    }
+    else
+    {
+        err_code              = NRF_ERROR_NO_MEM;
+    }
+    
+    return err_code;
+}
+
+
+uint32_t hci_mem_pool_tx_free(void)
+{
+    m_is_tx_allocated = false;
+    
+    return NRF_SUCCESS;
+}
+
+
+uint32_t hci_mem_pool_rx_produce(uint32_t length, void ** pp_buffer)
+{
+    uint32_t err_code; 
+
+    if (pp_buffer == NULL)
+    {
+        return NRF_ERROR_NULL;
+    }    
+    *pp_buffer = NULL;
+    
+    if (m_rx_buffer_queue.free_window_count != 0)
+    {    
+        if (length <= RX_BUF_SIZE)
+        {    
+            --(m_rx_buffer_queue.free_window_count);            
+            ++(m_rx_buffer_queue.read_available_count);            
+
+            *pp_buffer                    = 
+                    m_rx_buffer_queue.p_buffer[m_rx_buffer_queue.write_index].rx_buffer;
+
+            m_rx_buffer_queue.free_index |= (1u << m_rx_buffer_queue.write_index);
+
+            // @note: Adjust the write_index making use of the fact that the buffer size is of 
+            // power of two and two's complement arithmetic. For details refer example to book 
+            // "Making embedded systems: Elicia White".
+            m_rx_buffer_queue.write_index = 
+                    (m_rx_buffer_queue.write_index + 1u) & (RX_BUF_QUEUE_SIZE - 1u);
+            
+            err_code                      = NRF_SUCCESS;
+        }
+        else
+        {
+            err_code = NRF_ERROR_DATA_SIZE;    
+        }        
+    }
+    else
+    {
+        err_code = NRF_ERROR_NO_MEM;    
+    }
+    
+    return err_code;
+}
+
+
+uint32_t hci_mem_pool_rx_consume(uint8_t * p_buffer)
+{
+    uint32_t err_code;
+    uint32_t consume_index;
+    uint32_t start_index;
+    
+    if (m_rx_buffer_queue.free_available_count != 0)
+    {
+        // Find the buffer that has been freed -
+        // Start at read_index minus free_available_count and then increment until read index.
+        err_code      = NRF_ERROR_INVALID_ADDR;
+        consume_index = (m_rx_buffer_queue.read_index - m_rx_buffer_queue.free_available_count) & 
+                        (RX_BUF_QUEUE_SIZE - 1u);
+        start_index   = consume_index;
+        
+        do
+        {
+            if (m_rx_buffer_queue.p_buffer[consume_index].rx_buffer == p_buffer)
+            {
+                m_rx_buffer_queue.free_index ^= (1u << consume_index);
+                err_code = NRF_SUCCESS;
+                break;
+            }
+            else
+            {
+                consume_index = (consume_index + 1u) & (RX_BUF_QUEUE_SIZE - 1u);
+            }
+        }
+        while (consume_index != m_rx_buffer_queue.read_index);
+
+        while (!(m_rx_buffer_queue.free_index & (1 << start_index)) && 
+                (m_rx_buffer_queue.free_available_count != 0))
+        {
+            --(m_rx_buffer_queue.free_available_count);
+            ++(m_rx_buffer_queue.free_window_count);            
+            start_index = (consume_index + 1u) & (RX_BUF_QUEUE_SIZE - 1u);
+        }
+    }
+    else
+    {
+        err_code = NRF_ERROR_NO_MEM;
+    }
+        
+    return err_code;    
+}
+
+
+uint32_t hci_mem_pool_rx_data_size_set(uint32_t length)
+{
+    // @note: Adjust the write_index making use of the fact that the buffer size is of power
+    // of two and two's complement arithmetic. For details refer example to book 
+    // "Making embedded systems: Elicia White".
+    const uint32_t index = (m_rx_buffer_queue.write_index - 1u) & (RX_BUF_QUEUE_SIZE - 1u);
+    m_rx_buffer_queue.p_buffer[index].length = length;    
+    
+    return NRF_SUCCESS;
+}
+
+
+uint32_t hci_mem_pool_rx_extract(uint8_t ** pp_buffer, uint32_t * p_length)
+{
+    uint32_t err_code;
+    
+    if ((pp_buffer == NULL) || (p_length == NULL))
+    {
+        return NRF_ERROR_NULL;
+    }
+    
+    if (m_rx_buffer_queue.read_available_count != 0)
+    {
+        --(m_rx_buffer_queue.read_available_count);
+        ++(m_rx_buffer_queue.free_available_count);        
+        
+        *pp_buffer                   = 
+            m_rx_buffer_queue.p_buffer[m_rx_buffer_queue.read_index].rx_buffer;
+        *p_length                    = 
+            m_rx_buffer_queue.p_buffer[m_rx_buffer_queue.read_index].length;
+        
+        // @note: Adjust the write_index making use of the fact that the buffer size is of power
+        // of two and two's complement arithmetic. For details refer example to book 
+        // "Making embedded systems: Elicia White".            
+        m_rx_buffer_queue.read_index = 
+            (m_rx_buffer_queue.read_index + 1u) & (RX_BUF_QUEUE_SIZE - 1u); 
+        
+        err_code                     = NRF_SUCCESS;
+    }
+    else
+    {
+        err_code                     = NRF_ERROR_NO_MEM;        
+    }
+    
+    return err_code;
+}