#define MATRIX_ARB  (*(volatile U32*)(0x400FC188))
  MATRIX_ARB = 0            // Set AHB Matrix priorities [0..3] with 3 being highest priority
               | (1 <<  0)  // PRI_ICODE : I-Code bus priority. Should be lower than PRI_DCODE for proper operation.
               | (3 <<  2)  // PRI_DCODE : D-Code bus priority.
               | (0 <<  4)  // PRI_SYS   : System bus priority.
               | (0 <<  6)  // PRI_GPDMA : General Purpose DMA controller priority.
               | (0 <<  8)  // PRI_ETH   : Ethernet: DMA priority.
               | (3 << 10)  // PRI_LCD   : LCD DMA priority.
               | (0 << 12)  // PRI_USB   : USB DMA priority.
              ;  
  //MATRIX_ARB = 0x00000C09;