dma2.s

ppcboot2.0 华恒光盘里带的BOOTLOADER

/**************************************
 *
 * copyright @ Motorola, 1999
 *
 **************************************/

/**********************************************************
 * function: load_runtime_reg
 *
 * input:  r3 - value of eumbbar
 *         r4 - register offset in embedded utility space
 *
 * output: r3 - register content
 **********************************************************/
      .text
      .align 2
      .global load_runtime_reg

load_runtime_reg:

	      lwbrx	r3,r4,r3
	      sync

 	      bclr 20, 0

/****************************************************************
 * function: store_runtime_reg
 *
 * input: r3 - value of eumbbar
 *        r4 - register offset in embedded utility space
 *        r5 - new value to be stored
 *
 ****************************************************************/
           .text
           .align 2
           .global store_runtime_reg
store_runtime_reg:

	      stwbrx r5,  r4, r3
	      sync

		  bclr   20,0