Changes between Initial Version and Version 1 of Component/Vci Dma

Timestamp:

Oct 29, 2007, 12:04:38 PM (17 years ago)

Author:

Nicolas Pouillon

Comment:

DMA

Component/Vci Dma

@@ +1 @@
+[wiki:Component SocLib Components General Index] 
+
+= !VciDma Functional Description =
+
+This VCI component is both a target and an initiator.
+ * Addressing as a target allows to configure it for a transfer.
+ * Initiator will do the transfer
+
+There is only one DMA context handled at a time
+
+An IRQ is optionally asserted when transfer is finished.
+
+This hardware component cheks for segmentation violation, and can be used
+as a default target.
+
+= Memory region layout =
+
+ * `DMA_SRC`: ADDRESS![3:0] = 0x0
+The source of memory copy.
+
+ * `DMA_DST`: ADDRESS![3:0] = 0x4 
+The destination of memory copy
+
+ * `DMA_LEN`: ADDRESS![3:0] = 0x8
+Length of transfer, in bytes. Writing to this register initiates the transfer, you should write to it after src and dst.
+This register gets back to 0 when transfer is finished.
+
+ * `DMA_IRQ_ENABLED`: ADDRESS![3:0] = 0xC
+  * Written to: A boolean enabling the IRQ line (0 is disabling)
+  * Read from: A boolean indicating the completion of the transfer, (0 is completed)
+
+= Component usage =
+
+For extensibility issues, you should access the DMA using globally-defined offsets.
+
+You should include file source:trunk/soclib/include/soclib/dma.h from your software, it
+defines `DMA_SRC`, `DMA_DST`, `DMA_LEN`, `DMA_IRQ_ENABLED`.
+
+Sample code:
+{{{
+#include "soclib/dma.h"
+
+static const volatile void* dma_address = 0xc0000000;
+
+void * memcpy(void *dst, const void *src, const size_t len)
+{
+    volatile int *dma = ((int*)dma_address);
+
+    dma[DMA_DST] = (uint32_t)dst;
+    dma[DMA_SRC] = (uint32_t)dma;
+    dma[DMA_LEN] = (uint32_t)len;
+    while ( dma[DMA_LEN] )
+        ;
+    return dst;
+}
+
+}}}
+
+(add -I/path/to/soclib/include to your compilation command-line)
+
+= Component definition =
+
+Available in source:trunk/soclib/desc/soclib/vci_dma.sd
+
+== Usage ==
+
+!VciDma has no other parameter than VCI ones, it may be used like others, see [wiki:SoclibCc/VciParameters SoclibCc/VciParameters]
+{{{
+Uses( 'vci_dma', **vci_parameters )
+}}}
+
+= !VciDma CABA  Implementation =
+
+The caba implementation is in 
+ * source:trunk/soclib/systemc/include/caba/target/vci_dma.h
+ * source:trunk/soclib/systemc/src/caba/target/vci_dma.cc
+
+== Template parameters: ==
+
+ * The VCI parameters
+
+== Constructor parameters ==
+{{{
+VciDma(
+     sc_module_name name,   //  Component Name
+     const soclib::common::IntTab & index,  // Target index
+     const soclib::common::MappingTable &mt,   // MappingTable
+     const size_t burst_size );   //  Number of bytes transfered in a burst
+}}}
+
+== Ports ==
+
+ * sc_in<bool> '''p_resetn''' : Global system reset
+ * sc_in<bool> '''p_clk''' : Global system clock
+ * soclib::caba::!VciTarget<vci_param> '''p_vci_target''' : The VCI target port
+ * soclib::caba::!VciInitiator<vci_param> '''p_vci_initiator''' : The VCI initiator port
+ * sc_out<bool> '''p_irq''' : Interrupt port