/*---------------------------------------------------------------------- * * Copyright (c) 2005 Xilinx, Inc.  All rights reserved.  * Xilinx, Inc.  * * XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS" AS A  * COURTESY TO YOU.  BY PROVIDING THIS DESIGN, CODE, OR INFORMATION AS  * ONE POSSIBLE   IMPLEMENTATION OF THIS FEATURE, APPLICATION OR  * STANDARD, XILINX IS MAKING NO REPRESENTATION THAT THIS IMPLEMENTATION  * IS FREE FROM ANY CLAIMS OF INFRINGEMENT, AND YOU ARE RESPONSIBLE  * FOR OBTAINING ANY RIGHTS YOU MAY REQUIRE FOR YOUR IMPLEMENTATION.  * XILINX EXPRESSLY DISCLAIMS ANY WARRANTY WHATSOEVER WITH RESPECT TO  * THE ADEQUACY OF THE IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO  * ANY WARRANTIES OR REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE  * FROM CLAIMS OF INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY  * AND FITNESS FOR A PARTICULAR PURPOSE.  * * $Header: /devl/xcs/repo/env/Jobs/MDT/sw/Apps/debug/xmdstub/src/xmdstub.s,v 1.1.2.6 2005/11/15 23:29:47 salindac Exp $ * $Id: xmdstub.s,v 1.1.2.6 2005/11/15 23:29:47 salindac Exp $ * *	XMD_stub version 1.0                         *      MicroBlaze                                   *      Author: G鰎an Bilski                         *      Created:  11 Juli 2001	                    *      Modified: 20 Sept 2001                      	 *	Modified: 08 Nov  2001                      *	Modified: 12 Mar  2002 (jece & navanee)    	 *	Modified: 25 Aug  2004 (navanee) *	Modified: Jan 2005 (Raj - Added Half Word/Byte Read & Write)	  * ----------------------------------------------------------------------*/	/*--------------------------------------------------*/	/* MicroBlaze jump table                            */        /* 0x0  - Reset address                             */		/* 0x8  - Exception address                         */        /* 0x10 - Interrupt address                         */        /* 0x18 - Break signal address (short branch)       */	/* 0x1c - Breakpoint address (short branch)         */		/* 0x20 - Hardware Exception addr (MB ref guide)    */        /* 0x28 - Program Exit(crt1.s) (short branch)       */	/*--------------------------------------------------*/	.section .vectors.reset, "ax"	.align 2 _vector_reset:       			brki r16, StartUp_Entry	bri Program_Exit		.section .vectors.debug_sw_break, "ax"        .align 2_vector_debug_sw_break:       			bri Brk_Signal_Entry	bri Debug_Entry        .section .text        .align 2		        .globl _start	.globl	xmd_stub	.ent	xmd_stub _start:	xmd_stub:	.equ uart_rx_data,         DEBUG_PERIPHERAL_BASEADDRESS	.equ uart_tx_data,         DEBUG_PERIPHERAL_BASEADDRESS +  4	.equ uart_stat,	           DEBUG_PERIPHERAL_BASEADDRESS +  8	.equ uart_ctrl,		   DEBUG_PERIPHERAL_BASEADDRESS + 12		.equ uart_tx_buffer_empty, 0b100	.equ uart_rx_data_valid,   0b001		.equ uart_rst_rx_fifo,      0b010	.equ uart_rst_tx_fifo,      0b001		.equ Reached_End_Of_Program, 0x00	.equ Reached_Breakpoint,     0x01	.equ Received_brk_signal,    0x02	.equ ProcReset_signal,       0x03	.equ Escape_Char,            0xFC	.equ ReSync_Char,            0xFE	.equ Stub_ID,                0x40	.equ Reset_TxFifo,	     0x01	.equ Reset_RxFifo,	     0x02	.equ Clear_ExtBreak,	     0x04	.equ Intr_Enabled,	     0x10		.equ version, 4	/*--------------------------------------------------*/	/* ReSync                                           */	/* - Remove any stale data from the RX and TX fifo  */	/* - Send back the stubID + version number          */	/*--------------------------------------------------*/ReSync:	lwi  r15, r0, uart_stat	andi r15,r15, Intr_Enabled	ori  r15, r15, uart_rst_tx_fifo + uart_rst_rx_fifo	swi  r15, r0, uart_ctrl	brlid r29,Wait_for_TX_space	addi r30,r0,Stub_ID + version	swi  r30,r0,uart_tx_data	/*--------------------------------------------------*/	/* Main command entry code                          */	/* - Wait for the next command                      */	/*    0 = Download Program                          */	/*    4 = Continue                                  */	/*    8 = Read Registers                            */	/*   12 = Write Register                            */	/*   16 = Read Memory                               */	/*   20 = Write Memory                              */	/*   24 = Resync                                    */	/*   28 = Return Debug Addr - Deprecated	    */	/*   32 = Continue				    */		/*   36 = SingleStep                                */	/*   40 = Read Memory Half Word			    */	/*   44 = Read Memory Byte			    */	/*   48 = Write Memory Half Word		    */	/*   52 = Write Memory Byte			    */	/* - Call the command without any link              */	/*--------------------------------------------------*/Wait_for_command:		brlid r29,Get_Char	nop	lwi r29,r3,jump_table	bra r29	/*--------------------------------------------------*/	/* This section will end up in the rodata section    */	/* Is place here for helping understanding the code */	/*--------------------------------------------------*/	.rodata	.align 2jump_table:  	.int Load_Memory  	.int Execute  	.int Read_Register   	.int Write_Register	.int Read_Memory  	.int Write_Memory 	.int ReSync	.int Return_Dbg_Addr	.int Continue	.int SingleStep	.int Read_Memory_Half	.int Read_Memory_Byte	.int Write_Memory_Half	.int Write_Memory_Byte		/*--------------------------------------------------*/	/* Go back to the text section(instruction)         */	/*--------------------------------------------------*/		.text	/*--------------------------------------------------*/		/* Read all registers command                       */	/* Get the values of all registers                  */	/*   from the register_dump where the register      */	/*   values are stored                              */	/* - Send all values to the terminal (through UART) */	/*   33 words will be sent: 1-31 and pc and msr     */	/*   Note that the pc value sent is always incorrect*/	/*   It has to be in the table for consistency      */	/* - Jump to the main command entry code            */	/*--------------------------------------------------*/	Read_Register:		addi r28, r0, register_dump+4	addi r26, r0, 33Read_Register_1:			brlid r15, Send_32Bit	lw   r5, r28, r0	addi r26,r26,-1	bneid r26, Read_Register_1	addi r28,r28,4	bri Wait_for_command		/*--------------------------------------------------*/		/* Write to a register value command                */	/* - Get a byte which is the register asked for     */	/*   The byte has to be Register_Number*4,          */	/*   since the value will be used as word address   */        /*   and the addressing is always in byte addresses */	/*   ex. Want to see value of register 15           */	/*       The byte value has to be 4*15 = 60         */	/* - Get 32 bits (4 bytes) which is the new value   */	/*   for the register                               */	/* - Store the new value to the stored value for    */	/*   that register from the register_dump where the */	/*   register values are stored                     */	/* - Jump to the main command entry code            */	/*--------------------------------------------------*/	Write_Register:		/* Write a register value                    */	/* Next byte is which register               */	/* Next four bytes is the new register value */	brlid r29,Get_Char	nop	brlid r15,Get_32Bit	or r28,r3,r0	swi r3,r28,register_dump	bri Wait_for_command	/*--------------------------------------------------*/		/* Read from memory command                         */	/* - Get 32 bits (4 bytes) which is the memory      */	/*   address.                                       */	/* - Read the value from that memory address        */	/*   for the register                               */	/* - Send that value to the terminal (through UART) */	/* - Jump to the main command entry code            */	/*--------------------------------------------------*/	Read_Memory:	/* Next four bytes is the address */	/* The response will be the value in that address */	/* send as four bytes */	brlid r15,Get_32Bit	nop	brlid r15,Send_32Bit	lw r5,r3,r0	bri Wait_for_command	/*--------------------------------------------------*/		/* Read from memory Half Word command               */	/* - Get 32 bits (4 bytes) which is the memory      */	/*   address.                                       */	/* - Read the value from that memory address        */	/*   for the register                               */	/* - Send that value to the terminal (through UART) */	/* - Jump to the main command entry code            */	/*--------------------------------------------------*/	Read_Memory_Half:	/* Next four bytes is the address */	/* The response will be the value in that address */	/* send as two bytes */	brlid r15,Get_32Bit	nop	brlid r15,Send_16Bit	lhu r5,r3,r0	bri Wait_for_command	/*--------------------------------------------------*/		/* Read from memory Byte command                    */	/* - Get 32 bits (4 bytes) which is the memory      */	/*   address.                                       */	/* - Read the value from that memory address        */	/*   for the register                               */	/* - Send that value to the terminal (through UART) */	/* - Jump to the main command entry code            */	/*--------------------------------------------------*/		Read_Memory_Byte:	/* Next four bytes is the address */	/* The response will be the value in that address */	/* send a byte */	brlid r15,Get_32Bit	nop	brid Send_Status	lbu r15,r3,r0	/*--------------------------------------------------*/		/* Write to memory command                          */	/* - Get 32 bits (4 bytes) which is the memory      */	/*   address.                                       */	/* - Get 32 bits (4 bytes) which is the new value   */	/*   for that memory address.                       */	/* - Write the new value to the memory.             */	/* - Jump to the main command entry code            */	/*--------------------------------------------------*/	Write_Memory:	/* Next four byte is the address */	/* Then the next four byte is the new data */	brlid r15,Get_32Bit	nop	brlid r15,Get_32Bit	or r28,r3,r0	swi r3,r28,0	bri Wait_for_commandWrite_Memory_Half:	/* Next four bytes is the address */	/* Then the next two bytes is the new data */	brlid r15,Get_32Bit	nop	brlid r15,Get_16Bit	or r28,r3,r0	shi r3,r28,0	bri Wait_for_commandWrite_Memory_Byte:	/* Next four byte is the address */	/* Then the next byte is the new data */	brlid r15,Get_32Bit	nop	brlid r29,Get_Char	or r28,r3,r0	sbi r3,r28,0	bri Wait_for_command		/*--------------------------------------------------*/		/* Download program command                         */	/* - Get 32 bits (4 bytes) which is the start       */	/*   address for the downloading                    */	/* - Get 32 bits (4 bytes) which is the number of   */	/*   bytes in the downloading                       */	/* - Loop                                           */	/*   - Get a byte                                   */	/*   - Store it at the memory address               */	/*   - Increment the memory address with 1          */	/*   - Decrement the number of bytes by 1           */	/*   - Continue until all bytes has been received   */	/* - Jump to the main command entry code            */	/*--------------------------------------------------*/	Load_Memory:		/* Next 4 bytes is the start address */	/* The next four bytes is the number of bytes */	brlid r15,Get_32Bit	nop	brlid r15,Get_32Bit	or r28,r3,r0	or r25,r3,r0Load_Memory_1:		brlid r29,Get_Char	addi r25,r25,-1	sb r3,r28,r0	bneid r25,Load_Memory_1	addi r28,r28,1	bri Wait_for_command					/*--------------------------------------------------*/	/* NOTE : EXECUTE FOR THE SAKE OF COMPATIBILITY WITH MDK 2.2 */	/* Execute program command                          */	/* - Get 32 bits (4 bytes) which is the memory      */	/*   address.                                       */	/* - Load all register from the register_dump       */	/*--------------------------------------------------*/	Execute:	/* Next four byte is the start address */	brlid r15,Get_32Bit	nop	/* Set the R16 value in the reg dump to the start addr  */	/* When control falls thru to the Continue command      */	/* it will start execution from the addr in the new R16 */	swi r3,r0,register_dump+64	/* Fall thru to the following Continue command */		/*--------------------------------------------------*/	/* Continue command                                 */	/* continue at the instruction after the brk        */	/*  - Restore all registers                         */	/*  - jump to the address for the BRK instruction   */	/*--------------------------------------------------*/Continue:	brlid r15, Get_All_Registers	nop	rtbd r16, 0	lwi r15,r0,register_dump+15*4	/*--------------------------------------------------*/	/* SingleStep command                               */	/* step single instruction without enabling         */	/* the BIP flag                                     */	/*  - Restore all registers                         */	/*  - jump to the address for the BRK instruction   */