1 files changed, 117 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/arm/lpc176x/misc/dma.c b/c/src/lib/libbsp/arm/lpc176x/misc/dma.c
new file mode 100644
index 0000000000..97b32c940c
--- /dev/null
+++ b/c/src/lib/libbsp/arm/lpc176x/misc/dma.c
@@ -0,0 +1,117 @@
+/**
+ * @file
+ *
+ * @ingroup lpc176x_dma
+ *
+ * @brief Direct memory access (DMA) support.
+ */
+
+/*
+ * Copyright (c) 2008-2011 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  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 <rtems/endian.h>
+#include <bsp/dma.h>
+#include <bsp/io.h>
+
+/**
+ * @brief Table that indicates if a channel is currently occupied.
+ */
+static bool lpc176x_dma_channel_occupation[ GPDMA_CH_NUMBER ];
+
+void lpc176x_dma_initialize( void )
+{
+  /* Enable module power */
+  lpc176x_module_enable( LPC176X_MODULE_GPDMA, LPC176X_MODULE_PCLK_DEFAULT );
+
+  /* Disable module */
+  GPDMA_CONFIG = 0u;
+
+  /* Reset registers */
+  GPDMA_SOFT_SREQ = 0u;
+  GPDMA_SOFT_BREQ = 0u;
+  GPDMA_SOFT_LSREQ = 0u;
+  GPDMA_SOFT_LBREQ = 0u;
+  GPDMA_SYNC = 0u;
+  GPDMA_CH0_CFG = 0u;
+  GPDMA_CH1_CFG = 0u;
+
+  /* Enable module */
+#if BYTE_ORDER == LITTLE_ENDIAN
+  GPDMA_CONFIG = GPDMA_CONFIG_EN;
+#else
+  GPDMA_CONFIG = GPDMA_CONFIG_EN | GPDMA_CONFIG_MODE;
+#endif
+}
+
+rtems_status_code lpc176x_dma_channel_obtain( const unsigned channel )
+{
+  rtems_status_code status_code = RTEMS_INVALID_ID;
+
+  if ( channel < GPDMA_CH_NUMBER ) {
+    rtems_interrupt_level level = 0u;
+    bool                  occupation = true;
+
+    rtems_interrupt_disable( level );
+    occupation = lpc176x_dma_channel_occupation[ channel ];
+    lpc176x_dma_channel_occupation[ channel ] = true;
+    rtems_interrupt_enable( level );
+
+    status_code = occupation ? RTEMS_RESOURCE_IN_USE : RTEMS_SUCCESSFUL;
+  }
+
+  /* else implies that the channel is not valid. Also,
+     there is nothing to do. */
+
+  return status_code;
+}
+
+void lpc176x_dma_channel_release( const unsigned channel )
+{
+  if ( channel < GPDMA_CH_NUMBER ) {
+    lpc176x_dma_channel_occupation[ channel ] = false;
+  }
+
+  /* else implies that the channel is not valid. Also,
+     there is nothing to do. */
+}
+
+void lpc176x_dma_channel_disable(
+  const unsigned channel,
+  const bool     force
+)
+{
+  if ( channel < GPDMA_CH_NUMBER ) {
+    volatile lpc176x_dma_channel *ch = GPDMA_CH_BASE_ADDR( channel );
+    uint32_t                      cfg = ch->cfg;
+
+    if ( !force ) {
+      /* Halt */
+      ch->cfg |= GPDMA_CH_CFG_HALT;
+
+      /* Wait for inactive */
+      do {
+        cfg = ch->cfg;
+      } while ( ( cfg & GPDMA_CH_CFG_ACTIVE ) != 0u );
+    }
+
+    /* else implies that the channel is not to be forced. Also,
+       there is nothing to do. */
+
+    /* Disable */
+    ch->cfg &= ~GPDMA_CH_CFG_EN;
+  }
+
+  /* else implies that the channel is not valid. Also,
+     there is nothing to do. */
+}