Adding plasma example

plasma/kernel/flash.c

@@ -0,0 +1,52 @@
+/*--------------------------------------------------------------------
+ * TITLE: Plasma Flash
+ * AUTHOR: Steve Rhoads (rhoadss@yahoo.com)
+ * DATE CREATED: 12/17/05
+ * FILENAME: plasma.h
+ * PROJECT: Plasma CPU core
+ * COPYRIGHT: Software placed into the public domain by the author.
+ *    Software 'as is' without warranty.  Author liable for nothing.
+ * DESCRIPTION:
+ *    Plasma flash controller
+ *    Only the lower 16-bits of each 32-bit word are connected --
+ *    this changes the address mapping to the flash.
+ *    ByteOffset and bytes must be a multiple of two.
+ *--------------------------------------------------------------------*/
+#include "plasma.h"
+#include "rtos.h"
+
+
+void FlashRead(uint16 *dst, uint32 byteOffset, int bytes)
+{
+   volatile uint32 *ptr=(uint32*)(FLASH_BASE + (byteOffset << 1));
+   *ptr = 0xff;                   //read mode
+   while(bytes > 0)
+   {
+      *dst++ = (uint16)*ptr++;
+      bytes -= 2;
+   }
+}
+
+
+void FlashWrite(uint16 *src, uint32 byteOffset, int bytes)
+{
+   volatile uint32 *ptr=(uint32*)(FLASH_BASE + (byteOffset << 1));
+   while(bytes > 0)
+   {
+      *ptr = 0x40;                //write mode
+      *ptr++ = *src++;            //write data
+      while((*ptr & 0x80) == 0)   //check status
+         ;
+      bytes -= 2;
+   }
+}
+
+
+void FlashErase(uint32 byteOffset)
+{
+   volatile uint32 *ptr=(uint32*)(FLASH_BASE + (byteOffset << 1));
+   *ptr = 0x20;                   //erase block
+   *ptr = 0xd0;                   //confirm
+   while((*ptr & 0x80) == 0)      //check status
+      ;
+}