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authorChris Johns <chrisj@rtems.org>2017-12-23 18:18:56 +1100
committerSebastian Huber <sebastian.huber@embedded-brains.de>2018-01-25 08:45:26 +0100
commit2afb22b7e1ebcbe40373ff7e0efae7d207c655a9 (patch)
tree44759efe9374f13200a97e96d91bd9a2b7e5ce2a /bsps/arm/lpc24xx/include/bsp/dma.h
parentMAINTAINERS: Add myself to Write After Approval. (diff)
downloadrtems-2afb22b7e1ebcbe40373ff7e0efae7d207c655a9.tar.bz2
Remove make preinstall
A speciality of the RTEMS build system was the make preinstall step. It copied header files from arbitrary locations into the build tree. The header files were included via the -Bsome/build/tree/path GCC command line option. This has at least seven problems: * The make preinstall step itself needs time and disk space. * Errors in header files show up in the build tree copy. This makes it hard for editors to open the right file to fix the error. * There is no clear relationship between source and build tree header files. This makes an audit of the build process difficult. * The visibility of all header files in the build tree makes it difficult to enforce API barriers. For example it is discouraged to use BSP-specifics in the cpukit. * An introduction of a new build system is difficult. * Include paths specified by the -B option are system headers. This may suppress warnings. * The parallel build had sporadic failures on some hosts. This patch removes the make preinstall step. All installed header files are moved to dedicated include directories in the source tree. Let @RTEMS_CPU@ be the target architecture, e.g. arm, powerpc, sparc, etc. Let @RTEMS_BSP_FAMILIY@ be a BSP family base directory, e.g. erc32, imx, qoriq, etc. The new cpukit include directories are: * cpukit/include * cpukit/score/cpu/@RTEMS_CPU@/include * cpukit/libnetworking The new BSP include directories are: * bsps/include * bsps/@RTEMS_CPU@/include * bsps/@RTEMS_CPU@/@RTEMS_BSP_FAMILIY@/include There are build tree include directories for generated files. The include directory order favours the most general header file, e.g. it is not possible to override general header files via the include path order. The "bootstrap -p" option was removed. The new "bootstrap -H" option should be used to regenerate the "headers.am" files. Update #3254.
Diffstat (limited to 'bsps/arm/lpc24xx/include/bsp/dma.h')
-rw-r--r--bsps/arm/lpc24xx/include/bsp/dma.h95
1 files changed, 95 insertions, 0 deletions
diff --git a/bsps/arm/lpc24xx/include/bsp/dma.h b/bsps/arm/lpc24xx/include/bsp/dma.h
new file mode 100644
index 0000000000..b2e6c3e665
--- /dev/null
+++ b/bsps/arm/lpc24xx/include/bsp/dma.h
@@ -0,0 +1,95 @@
+/**
+ * @file
+ *
+ * @ingroup lpc24xx_dma
+ *
+ * @brief Direct memory access (DMA) support.
+ */
+
+/*
+ * 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.org/license/LICENSE.
+ */
+
+#ifndef LIBBSP_ARM_LPC24XX_DMA_H
+#define LIBBSP_ARM_LPC24XX_DMA_H
+
+#include <rtems.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/**
+ * @defgroup lpc24xx_dma DMA Support
+ *
+ * @ingroup lpc24xx
+ *
+ * @brief Direct memory access (DMA) support.
+ *
+ * @{
+ */
+
+/**
+ * @brief Initializes the general purpose DMA.
+ */
+void lpc24xx_dma_initialize(void);
+
+/**
+ * @brief Tries to obtain the DMA channel @a channel.
+ *
+ * @retval RTEMS_SUCCESSFUL Successful operation.
+ * @retval RTEMS_INVALID_ID Invalid channel number.
+ * @retval RTEMS_RESOURCE_IN_USE Channel already occupied.
+ */
+rtems_status_code lpc24xx_dma_channel_obtain(unsigned channel);
+
+/**
+ * @brief Releases the DMA channel @a channel.
+ *
+ * You must have obtained this channel with lpc24xx_dma_channel_obtain()
+ * previously.
+ *
+ * If the channel number @a channel is out of range nothing will happen.
+ */
+void lpc24xx_dma_channel_release(unsigned channel);
+
+/**
+ * @brief Disables the DMA channel @a channel.
+ *
+ * If @a force is @c false the channel will be halted and disabled when the
+ * channel is inactive otherwise it will be disabled immediately.
+ *
+ * If the channel number @a channel is out of range nothing will happen.
+ */
+void lpc24xx_dma_channel_disable(unsigned channel, bool force);
+
+rtems_status_code lpc24xx_dma_copy_initialize(void);
+
+rtems_status_code lpc24xx_dma_copy_release(void);
+
+rtems_status_code lpc24xx_dma_copy(
+ unsigned channel,
+ void *dest,
+ const void *src,
+ size_t n,
+ size_t width
+);
+
+rtems_status_code lpc24xx_dma_copy_wait(unsigned channel);
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* LIBBSP_ARM_LPC24XX_DMA_H */