There was an issue revealed in gdb testing where C++ virtual tables were not getting properly initialized. This seems to be due to the c++ global constructors moving from ctors to init_array. This fix makes sure we call the proper method for initializing the constructors in all places.
		
			
				
	
	
		
			678 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			678 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /* crt0.S -- startup file for OpenRISC 1000.
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|  *
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|  * Copyright (c) 2011, 2014 Authors
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|  *
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|  * Contributor Julius Baxter <juliusbaxter@gmail.com>
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|  * Contributor Stefan Wallentowitz <stefan.wallentowitz@tum.de>
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|  *
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|  * The authors hereby grant permission to use, copy, modify, distribute,
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|  * and license this software and its documentation for any purpose, provided
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|  * that existing copyright notices are retained in all copies and that this
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|  * notice is included verbatim in any distributions. No written agreement,
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|  * license, or royalty fee is required for any of the authorized uses.
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|  * Modifications to this software may be copyrighted by their authors
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|  * and need not follow the licensing terms described here, provided that
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|  * the new terms are clearly indicated on the first page of each file where
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|  * they apply.
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|  */
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| 
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| /* -------------------------------------------------------------------------- */
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| /* Coding convention:
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|    Assembly is hard to read per se, so please follow the following coding
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|    conventions to keep it consistent and ease reading:
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|     * internal jump labels start with L, no identation
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|     * assemble lines have one tab identation
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|     * attributes (.section, .global, ..) are indented with one tab
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|     * code is structured using tabs, i.e., use 'l.sw\t0(r1),r1' with a single
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|       tab. libgloss assumes 8 space tab width, so that might look unstructured
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|       with tab widths below 6. Nevertheless don't use spaces or two tabs.
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|     * no space after comma
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|     * use the defined macros if possible as they reduce errors
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|     * use OR1K_INST with OR1K_DELAYED(_NOP)
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|     * OR1K_DELAYED is multiline for better readability, the inner parts are
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|       indented with another tab.
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|     * COMMENT! Try to accompy every line with a meaningful comment. If possible
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|       use pseudo code to describe the code. Also mention intentions and not only
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|       the obvious things..                                                    */
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| /* -------------------------------------------------------------------------- */
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| 
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| #include "newlib.h"
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| #include "include/or1k-asm.h"
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| #include "include/or1k-sprs.h"
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| 
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| /* -------------------------------------------------------------------------- */
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| // Stack definitions
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| /* -------------------------------------------------------------------------- */
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| 
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| // Stacks
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| // Memory layout:
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| //  +--------------------+ <- board_mem_base+board_mem_size/exception_stack_top
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| //  | exception stack(s) |
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| //  +--------------------+ <- stack_top
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| //  |     stack(s)       |
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| //  +--------------------+ <- stack_bottom
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| //  |      heap          |
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| //  +--------------------+
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| //  | text, data, bss..  |
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| //  +--------------------+
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| 
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| // Reserved stack size
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| #define STACK_SIZE 8192
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| 
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| // Reserved stack size for exceptions (can usually be smaller than normal stack)
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| #define EXCEPTION_STACK_SIZE 8192
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| 
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| // Size of space required to store state
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| // This value must match that in the support library or1k_exception_handler
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| // function
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| #define EXCEPTION_STACK_FRAME 136
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| 
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| #define REDZONE 128
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| 
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| 	.extern _or1k_stack_top    /* points to the next address after the stack */
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| 	.extern _or1k_stack_bottom /* points to the last address in the stack */
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| 	.extern _or1k_exception_stack_top
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| 	.extern _or1k_exception_stack_bottom
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| 	.extern _or1k_exception_level /* Nesting level of exceptions */
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| 
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| 	.section .data
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| 	.global _or1k_stack_size /* reserved stack size */
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| 	.global _or1k_exception_stack_size
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| 	.global _or1k_exception_level
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| 
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| _or1k_stack_size:		.word STACK_SIZE
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| _or1k_exception_stack_size:	.word EXCEPTION_STACK_SIZE
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| 
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| #ifdef __OR1K_MULTICORE__
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| 	.extern _or1k_stack_core
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| 	.extern _or1k_exception_stack_core
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| #endif
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| 
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| #define SHADOW_REG(x) (OR1K_SPR_SYS_GPR_BASE + 32 + x)
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| 
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| /* -------------------------------------------------------------------------- */
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| /*!Macro to handle exceptions.
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| 
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|   Load NPC into r3, EPCR into r4
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|                                                                               */
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| /* -------------------------------------------------------------------------- */
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| 
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| #ifdef HAVE_INITFINI_ARRAY
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| #define _init	__libc_init_array
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| #define _fini	__libc_fini_array
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| #endif
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| 
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| #define GPR_BUF_OFFSET(x) (x << 2)
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| 
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| #ifndef __OR1K_MULTICORE__
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| #define CALL_EXCEPTION_HANDLER(id)				\
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| 	/* Store current stack pointer to address 4 */		\
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| 	l.sw	0x4(r0),r1;					\
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| 	/* Load address of exception nesting level */		\
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| 	l.movhi	r1,hi(_or1k_exception_level);			\
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| 	l.ori	r1,r1,lo(_or1k_exception_level);		\
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| 	/* Load the current nesting level */			\
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| 	l.lwz	r1,0(r1);					\
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| 	/* Set flag if this is the outer (first) exception */	\
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| 	l.sfeq	r1,r0;						\
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| 	/* Branch to the code for nested exceptions */		\
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| 	OR1K_DELAYED_NOP(					\
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| 		OR1K_INST(l.bnf .Lnested_##id)			\
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| 	);							\
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| 	/* Load top of the exception stack */			\
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| 	l.movhi	r1,hi(_or1k_exception_stack_top);		\
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| 	l.ori	r1,r1,lo(_or1k_exception_stack_top);		\
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| 	OR1K_DELAYED(						\
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| 		/* Load value from array to stack pointer */	\
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| 		OR1K_INST(l.lwz r1,0(r1)),			\
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| 		/* and jump over the nested code */		\
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| 		OR1K_INST(l.j   .Lnesting_done_##id)		\
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| 	);							\
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| .Lnested_##id:							\
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| 	/* Load back the stack pointer */			\
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| 	l.lwz	r1,0x4(r0);					\
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| 	/* Add redzone, nesting needs this */			\
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| 	l.addi	r1,r1,-REDZONE;					\
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| .Lnesting_done_##id:						\
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| 	/* Reserve red zone and context space */		\
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| 	l.addi	r1,r1,-EXCEPTION_STACK_FRAME;			\
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| 	/* Store GPR3 in context */				\
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| 	l.sw	GPR_BUF_OFFSET(3)(r1),r3;			\
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| 	/* Load back software's stack pointer */		\
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| 	l.lwz	r3,0x4(r0);					\
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| 	/* Store this in the context */				\
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| 	l.sw	GPR_BUF_OFFSET(1)(r1),r3;			\
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| 	/* Store GPR4 in the context */				\
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| 	l.sw	GPR_BUF_OFFSET(4)(r1),r4;			\
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| 	/* Load address of the exception level */		\
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| 	l.movhi	r3,hi(_or1k_exception_level);			\
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| 	l.ori	r3,r3,lo(_or1k_exception_level);		\
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| 	/* Load current value */				\
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| 	l.lwz	r4,0(r3);					\
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| 	/* Increment level */					\
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| 	l.addi	r4,r4,1;					\
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| 	/* Store back */					\
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| 	l.sw	0(r3),r4;					\
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| 	/* Copy the current program counter as first */		\
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| 	/* argument for the exception handler. This */		\
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| 	/* is then used to determine the exception. */		\
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| 	l.mfspr	r3,r0,OR1K_SPR_SYS_NPC_ADDR;			\
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| 	OR1K_DELAYED(						\
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| 	/* Copy program counter of exception as */		\
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| 	/* second argument to the exception handler */		\
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| 		OR1K_INST(l.mfspr r4,r0,OR1K_SPR_SYS_EPCR_BASE),\
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| 	/* Jump to exception handler. This will rfe */		\
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| 		OR1K_INST(l.j _or1k_exception_handler)		\
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| 	)
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| #else
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| #define CALL_EXCEPTION_HANDLER(id)				\
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| 	/* Store current stack pointer to shadow reg */		\
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| 	l.mtspr	r0,r1,SHADOW_REG(1);				\
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| 	/* Store current GPR3 for temporary use */		\
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| 	l.mtspr	r0,r3,SHADOW_REG(2);				\
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| 	/* Store current GPR2 for the level pointer */		\
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| 	l.mtspr	r0,r4,SHADOW_REG(3);				\
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| 	/* Load nesting level of exceptions */			\
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| 	l.movhi	r4,hi(_or1k_exception_level);			\
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| 	l.ori	r4,r4,lo(_or1k_exception_level);		\
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| 	/* Load array pointer */				\
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| 	l.lwz	r4,0(r4);					\
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| 	/* Get core id */					\
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| 	l.mfspr	r3,r0,OR1K_SPR_SYS_COREID_ADDR;			\
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| 	/* Generate offset */					\
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| 	l.slli	r3,r3,2;					\
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| 	/* Generate core nesting level address */		\
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| 	l.add	r4,r4,r3;					\
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| 	/* Load nesting level */				\
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| 	l.lwz	r3,0(r4);					\
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| 	/* Increment nesting level */				\
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| 	l.addi	r3,r3,1;					\
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| 	/* Write back nesting level */				\
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| 	l.sw	0(r4),r3;					\
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| 	/* Set flag if this is the outer (first) exception */	\
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| 	l.sfeqi	r3,1;						\
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| 	/* Branch to the code for nested exceptions */		\
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| 	OR1K_DELAYED_NOP(					\
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| 		OR1K_INST(l.bnf .Lnested_##id)			\
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| 	);							\
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| 	/* Load pointer to exception stack array */		\
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| 	l.movhi	r1,hi(_or1k_exception_stack_core);		\
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| 	l.ori	r1,r1,lo(_or1k_exception_stack_core);		\
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| 	l.lwz	r1,0(r1);					\
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| 	/* Get core id */					\
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| 	l.mfspr	r3,r0,OR1K_SPR_SYS_COREID_ADDR;			\
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| 	/* Calculate offset in array */				\
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| 	l.slli	r3,r3,2;					\
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| 	l.add	r1,r1,r3;					\
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| 	OR1K_DELAYED(						\
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| 		/* Load value from array to stack pointer */	\
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| 		OR1K_INST(l.lwz r1,0(r1)),			\
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| 		/* and jump over nested exception pointer */	\
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| 		OR1K_INST(l.j .Lnesting_done_##id)		\
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| 	);							\
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| .Lnested_##id:							\
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| 	/* The stack pointer is still active */			\
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| 	/* Add redzone, nesting needs this */			\
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| 	l.addi	r1,r1,-REDZONE;					\
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| .Lnesting_done_##id:						\
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| 	/* Reserve context space */				\
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| 	l.addi	r1,r1,-EXCEPTION_STACK_FRAME;			\
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| 	/* Load back software's stack pointer */		\
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| 	l.mfspr	r3,r0,SHADOW_REG(1);				\
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| 	/* Store this in the context */				\
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| 	l.sw	GPR_BUF_OFFSET(1)(r1),r3;			\
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| 	/* Load back GPR3 */					\
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| 	l.mfspr	r3,r0,SHADOW_REG(2);				\
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| 	/* Store this in the context */				\
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| 	l.sw	GPR_BUF_OFFSET(3)(r1),r3;			\
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| 	/* Load back GPR4 */					\
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| 	l.mfspr	r4,r0,SHADOW_REG(3);				\
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| 	/* Store GPR4 in the context */				\
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| 	l.sw	GPR_BUF_OFFSET(4)(r1),r4;			\
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| 	/* Copy the current program counter as first */		\
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| 	/* argument for the exception handler. This */		\
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| 	/* is then used to determine the exception. */		\
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| 	l.mfspr	r3,r0,OR1K_SPR_SYS_NPC_ADDR;			\
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| 	OR1K_DELAYED(						\
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| 	/* Copy program counter of exception as */		\
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| 	/* second argument to the exception handler */		\
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| 		OR1K_INST(l.mfspr r4,r0,OR1K_SPR_SYS_EPCR_BASE),\
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| 	/* Jump to exception handler. This will rfe */		\
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| 		OR1K_INST(l.j _or1k_exception_handler)		\
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| 	)
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| #endif
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| 
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| /* -------------------------------------------------------------------------- */
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| /*!Exception vectors                                                          */
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| /* -------------------------------------------------------------------------- */
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| 	.section .vectors,"ax"
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| 
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| 	/* 0x100: RESET exception */
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| 	.org 0x100
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| _or1k_reset:
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| 	l.movhi	r0,0
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| #ifdef __OR1K_MULTICORE__
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| 	// This is a hack that relies on the fact, that all cores start at the
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| 	// same time and they are similarily fast
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| 	l.sw	0x4(r0),r0
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| 	// Similarly, we use address 8 to signal how many cores have exit'ed
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| 	l.sw	0x8(r0),r0
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| #endif
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| 	l.movhi	r1,0
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| 	l.movhi	r2,0
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| 	l.movhi	r3,0
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| 	l.movhi	r4,0
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| 	l.movhi	r5,0
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| 	l.movhi	r6,0
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| 	l.movhi	r7,0
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| 	l.movhi	r8,0
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| 	l.movhi	r9,0
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| 	l.movhi	r10,0
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| 	l.movhi	r11,0
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| 	l.movhi	r12,0
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| 	l.movhi	r13,0
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| 	l.movhi	r14,0
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| 	l.movhi	r15,0
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| 	l.movhi	r16,0
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| 	l.movhi	r17,0
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| 	l.movhi	r18,0
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| 	l.movhi	r19,0
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| 	l.movhi	r20,0
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| 	l.movhi	r21,0
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| 	l.movhi	r22,0
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| 	l.movhi	r23,0
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| 	l.movhi	r24,0
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| 	l.movhi	r25,0
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| 	l.movhi	r26,0
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| 	l.movhi	r27,0
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| 	l.movhi	r28,0
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| 	l.movhi	r29,0
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| 	l.movhi	r30,0
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| 	l.movhi	r31,0
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| 
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| 	/* Clear status register, set supervisor mode */
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| 	l.ori	r1,r0,OR1K_SPR_SYS_SR_SM_MASK
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| 	l.mtspr	r0,r1,OR1K_SPR_SYS_SR_ADDR
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| 	/* Clear timer mode register*/
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| 	l.mtspr	r0,r0,OR1K_SPR_TICK_TTMR_ADDR
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| 	/* Jump to program initialisation code */
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| 	LOAD_SYMBOL_2_GPR(r4, _or1k_start)
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| 	OR1K_DELAYED_NOP(OR1K_INST(l.jr r4))
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| 
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| 	.org 0x200
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| 	CALL_EXCEPTION_HANDLER(2)
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| 
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| 	/* 0x300: Data Page Fault exception */
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| 	.org 0x300
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| 	CALL_EXCEPTION_HANDLER(3)
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| 
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| 	/* 0x400: Insn Page Fault exception */
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| 	.org 0x400
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| 	CALL_EXCEPTION_HANDLER(4)
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| 
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| 	/* 0x500: Timer exception */
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| 	.org 0x500
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| 	CALL_EXCEPTION_HANDLER(5)
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| 
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| 	/* 0x600: Aligment exception */
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| 	.org 0x600
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| 	CALL_EXCEPTION_HANDLER(6)
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| 
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| 	/* 0x700: Illegal insn exception */
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| 	.org 0x700
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| 	CALL_EXCEPTION_HANDLER(7)
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| 
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| 	/* 0x800: External interrupt exception */
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| 	.org 0x800
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| 	CALL_EXCEPTION_HANDLER(8)
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| 
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| 	/* 0x900: DTLB miss exception */
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| 	.org 0x900
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| 	CALL_EXCEPTION_HANDLER(9)
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| 
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| 	/* 0xa00: ITLB miss exception */
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| 	.org 0xa00
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| 	CALL_EXCEPTION_HANDLER(10)
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| 
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| 	/* 0xb00: Range exception */
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| 	.org 0xb00
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| 	CALL_EXCEPTION_HANDLER(11)
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| 
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| 	/* 0xc00: Syscall exception */
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| 	.org 0xc00
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| 	CALL_EXCEPTION_HANDLER(12)
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| 
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| 	/* 0xd00: Floating point exception */
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| 	.org 0xd00
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| 	CALL_EXCEPTION_HANDLER(13)
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| 
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| 	/* 0xe00: Trap exception */
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| 	.org 0xe00
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| 	CALL_EXCEPTION_HANDLER(14)
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| 
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| 	/* 0xf00: Reserved exceptions */
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| 	.org 0xf00
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| 	CALL_EXCEPTION_HANDLER(15)
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| 
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| 	.org 0x1000
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| 	CALL_EXCEPTION_HANDLER(16)
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| 
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| 	.org 0x1100
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| 	CALL_EXCEPTION_HANDLER(17)
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| 
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| 	.org 0x1200
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| 	CALL_EXCEPTION_HANDLER(18)
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| 
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| 	.org 0x1300
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| 	CALL_EXCEPTION_HANDLER(19)
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| 
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| 	.org 0x1400
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| 	CALL_EXCEPTION_HANDLER(20)
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| 
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| 	.org 0x1500
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| 	CALL_EXCEPTION_HANDLER(21)
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| 
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| 	.org 0x1600
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| 	CALL_EXCEPTION_HANDLER(22)
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| 
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| 	.org 0x1700
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| 	CALL_EXCEPTION_HANDLER(23)
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| 
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| 	.org 0x1800
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| 	CALL_EXCEPTION_HANDLER(24)
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| 
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| 	.org 0x1900
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| 	CALL_EXCEPTION_HANDLER(25)
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| 
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| 	.org 0x1a00
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| 	CALL_EXCEPTION_HANDLER(26)
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| 
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| 	.org 0x1b00
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| 	CALL_EXCEPTION_HANDLER(27)
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| 
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| 	.org 0x1c00
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| 	CALL_EXCEPTION_HANDLER(28)
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| 
 | |
| 	.org 0x1d00
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| 	CALL_EXCEPTION_HANDLER(29)
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| 
 | |
| 	.org 0x1e00
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| 	CALL_EXCEPTION_HANDLER(30)
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| 
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| 	.org 0x1f00
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| 	CALL_EXCEPTION_HANDLER(31)
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| 
 | |
| 	/* Pad to the end */
 | |
| 	.org 0x1ffc
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| 	l.nop
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| 
 | |
| /* -------------------------------------------------------------------------- */
 | |
| /*!Main entry point
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| 
 | |
|   This is the initialization code of the library. It performs these steps:
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| 
 | |
|    * Call early board initialization:
 | |
|      Before anything happened, the board support may do some very early
 | |
|      initialization. This is at maximum some very basic stuff that would
 | |
|      otherwise prevent the following code from functioning. Other initialization
 | |
|      of peripherals etc. is done later (before calling main).
 | |
|      See the description below and README.board for details.
 | |
| 
 | |
|    * Initialize the stacks:
 | |
|      Two stacks are configured: The system stack is used by the software and
 | |
|      the exception stack is used when an exception occurs. We added this as
 | |
|      this should be flexible with respect to the usage of virtual memory.
 | |
| 
 | |
|    * Activate the caches:
 | |
|      If available the caches are initiliazed and activated.
 | |
| 
 | |
|    * Clear BSS:
 | |
|      The BSS are essentially the uninitialized C variables. They are set to 0
 | |
|      by default. This is performed by this function.
 | |
| 
 | |
|    * Initialize the impure data structure:
 | |
|      Similarly, we need two library contexts, one for the normal software and
 | |
|      one that is used during exceptions. The impure data structure holds
 | |
|      the context information of the library. The called C function will setup
 | |
|      both data structures. There is furthermore a pointer to the currently
 | |
|      active impure data structure, which is initially set to the normal one.
 | |
| 
 | |
|    * Initialize or1k support library reentrant data structures
 | |
| 
 | |
|    * Initialize constructors:
 | |
|      Call the static and global constructors
 | |
| 
 | |
|    * Set up destructors to call from exit
 | |
|      The library will call the function set via atexit() during exit(). We set
 | |
|      it to call the _fini function which performs destruction.
 | |
| 
 | |
|    * Call board initialization:
 | |
|      The board initialization can perform board specific initializations such as
 | |
|      configuring peripherals etc.
 | |
| 
 | |
|    * Jump to main
 | |
|      Call main with argc = 0 and *argv[] = 0
 | |
| 
 | |
|    * Call exit after main returns
 | |
|      Now we call exit()
 | |
| 
 | |
|    * Loop forever
 | |
|      We are dead.
 | |
| */
 | |
| 
 | |
| /* -------------------------------------------------------------------------- */
 | |
| 	.section	.text
 | |
| 
 | |
| 	/* Following externs from board-specific object passed at link time */
 | |
| 	.extern _or1k_board_mem_base
 | |
| 	.extern _or1k_board_mem_size
 | |
| 	.extern _or1k_board_uart_base
 | |
| 
 | |
| 	/* The early board initialization may for example read the memory size and
 | |
| 	   set the mem_base and mem_size or do some preliminary board
 | |
| 	   initialization. As we do not have a stack at this time, the function may
 | |
| 	   not use the stack (and therefore be a or call a C function. But it can
 | |
| 	   safely use all registers.
 | |
| 
 | |
| 	   We define a default implementation, which allows board files in C. As
 | |
| 	   described above, this can only be used in assembly (board_*.S) as at
 | |
| 	   the early stage not stack is available. A board that needs early
 | |
| 	   initialization can overwrite the function with .global _board_init_early.
 | |
| 
 | |
| 	   Recommendation: Only use when you really need it! */
 | |
| 	.weak _or1k_board_init_early
 | |
| _or1k_board_init_early:
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.jr r9))
 | |
| 
 | |
| 	/* The board initialization is then called after the C library and UART
 | |
| 	   are initialized. It can then be used to configure UART or other
 | |
| 	   devices before the actual main function is called. */
 | |
| 	.extern _or1k_board_init
 | |
| 
 | |
| 	.global	_or1k_start
 | |
| 	.type	_or1k_start,@function
 | |
| _or1k_start:
 | |
| 	/* It is good to initialize and enable the caches before we do anything,
 | |
| 	   otherwise the cores will continuously access the bus during the wait
 | |
| 	   time for the boot barrier (0x4).
 | |
| 	   Fortunately or1k_cache_init does not need a stack */
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.jal _or1k_cache_init))
 | |
| 
 | |
| #ifdef __OR1K_MULTICORE__
 | |
| 	// All but core 0 have to wait
 | |
| 	l.mfspr	r1, r0, OR1K_SPR_SYS_COREID_ADDR
 | |
| 	l.sfeq	r1, r0
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.bf .Lcore0))
 | |
| .Lspin:
 | |
| 	/* r1 will be used by the other cores to check for the boot variable
 | |
| 	   Check if r1 is still zero, core 0 will set it to 1 once it booted
 | |
| 	   As the cache is already turned on, this will not create traffic on
 | |
| 	   the bus, but the change is snooped by cache coherency then */
 | |
| 	l.lwz r1,0x4(r0)
 | |
| 	l.sfeq r1, r0
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.bf .Lspin))
 | |
| 
 | |
| 	/* Initialize core i stack */
 | |
| 	// _or1k_stack_core is the array of stack pointers
 | |
| 	LOAD_SYMBOL_2_GPR(r2,_or1k_stack_core)
 | |
| 	// Load the base address
 | |
| 	l.lwz	r2,0(r2)
 | |
| 	// Generate offset in array
 | |
| 	l.mfspr	r1,r0,OR1K_SPR_SYS_COREID_ADDR
 | |
| 	l.slli	r1,r1,2
 | |
| 	// Add to array base
 | |
| 	l.add	r2,r2,r1
 | |
| 	// Load pointer to the stack top and set frame pointer
 | |
| 	l.lwz	r1,0(r2)
 | |
| 	l.or	r2,r1,r1
 | |
| 
 | |
| 	// The slave cores are done, jump to main part
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.j .Linit_done));
 | |
| 
 | |
| 	/* Only core 0 executes the initialization code */
 | |
| .Lcore0:
 | |
| #endif
 | |
| 	/* Call early board initialization */
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.jal _or1k_board_init_early))
 | |
| 
 | |
| 	/* Clear BSS */
 | |
| .Lclear_bss:
 | |
| 	LOAD_SYMBOL_2_GPR(r3,__bss_start)
 | |
| 	LOAD_SYMBOL_2_GPR(r4,end)
 | |
| 
 | |
| .Lclear_bss_loop:
 | |
| 	l.sw	(0)(r3),r0
 | |
| 	l.sfltu r3,r4
 | |
| 	OR1K_DELAYED(
 | |
| 		OR1K_INST(l.addi r3,r3,4),
 | |
| 		OR1K_INST(l.bf .Lclear_bss_loop)
 | |
| 	)
 | |
| 
 | |
| 	/* Initialise stack and frame pointer (set to same value) */
 | |
| 	LOAD_SYMBOL_2_GPR(r1,_or1k_board_mem_base)
 | |
| 	l.lwz	r1,0(r1)
 | |
| 	LOAD_SYMBOL_2_GPR(r2,_or1k_board_mem_size)
 | |
| 	l.lwz	r2,0(r2)
 | |
| 	l.add	r1,r1,r2
 | |
| 
 | |
| 	/* Store exception stack top address */
 | |
| 	LOAD_SYMBOL_2_GPR(r3,_or1k_exception_stack_top)
 | |
| 	l.sw	0(r3),r1
 | |
| 
 | |
| 	/* Store exception stack bottom address */
 | |
| 	// calculate bottom address
 | |
| 	// r3 = *exception stack size
 | |
| 	LOAD_SYMBOL_2_GPR(r3,_or1k_exception_stack_size)
 | |
| 	// r3 = exception stack size
 | |
| 	l.lwz	r3,0(r3)
 | |
| #ifdef __OR1K_MULTICORE__
 | |
| 	l.mfspr	r4,r0,OR1K_SPR_SYS_NUMCORES_ADDR
 | |
| 	l.mul	r3,r4,r3
 | |
| #endif
 | |
| 	// r4 = exception stack top - exception stack size = exception stack bottom
 | |
| 	l.sub	r4,r1,r3
 | |
| 	// r5 = *exception stack bottom
 | |
| 	LOAD_SYMBOL_2_GPR(r5,_or1k_exception_stack_bottom)
 | |
| 	// store
 | |
| 	l.sw	0(r5),r4
 | |
| 
 | |
| 	// Move stack pointer accordingly
 | |
| 	l.or	r1,r0,r4
 | |
| 	l.or	r2,r1,r1
 | |
| 
 | |
| 	/* Store stack top address */
 | |
| 	LOAD_SYMBOL_2_GPR(r3,_or1k_stack_top)
 | |
| 	l.sw	0(r3),r1
 | |
| 
 | |
| 	/* Store stack bottom address */
 | |
| 	// calculate bottom address
 | |
| 	// r3 = stack size
 | |
| 	LOAD_SYMBOL_2_GPR(r3,_or1k_stack_size)
 | |
| 	l.lwz	r3,0(r3)
 | |
| #ifdef __OR1K_MULTICORE__
 | |
| 	l.mfspr	r4, r0, OR1K_SPR_SYS_NUMCORES_ADDR
 | |
| 	l.mul	r3, r4, r3
 | |
| #endif
 | |
| 	// r4 = stack top - stack size = stack bottom
 | |
| 	// -> stack bottom
 | |
| 	l.sub	r4,r1,r3
 | |
| 	// r5 = *exception stack bottom
 | |
| 	LOAD_SYMBOL_2_GPR(r5,_or1k_stack_bottom)
 | |
| 	// store to variable
 | |
| 	l.sw	0(r5),r4
 | |
| 
 | |
| 	/* Reinitialize the or1k support library */
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.jal _or1k_init))
 | |
| 
 | |
| 	/* Reinitialize the reentrancy structure */
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.jal _or1k_libc_impure_init))
 | |
| 
 | |
| 	/* Call global and static constructors */
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.jal _init))
 | |
| 
 | |
| 	/* Set up destructors to be called from exit if main ever returns */
 | |
| 	l.movhi	r3,hi(_fini)
 | |
| 	OR1K_DELAYED(
 | |
| 		OR1K_INST(l.ori r3,r3,lo(_fini)),
 | |
| 		OR1K_INST(l.jal atexit)
 | |
| 	)
 | |
| 
 | |
| 	/* Check if UART is to be initialised */
 | |
| 	LOAD_SYMBOL_2_GPR(r4,_or1k_board_uart_base)
 | |
| 	l.lwz	r4,0(r4)
 | |
| 	/* Is base set? If not, no UART */
 | |
| 	l.sfne	r4,r0
 | |
| 	l.bnf	.Lskip_uart
 | |
| 	l.or	r3,r0,r0
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.jal _or1k_uart_init))
 | |
| 
 | |
| .Lskip_uart:
 | |
| 	/* Board initialization */
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.jal _or1k_board_init))
 | |
| 
 | |
| #ifdef __OR1K_MULTICORE__
 | |
| 	// Start other cores
 | |
| 	l.ori	r3, r0, 1
 | |
| 	l.sw	0x4(r0), r3
 | |
| #endif
 | |
| 
 | |
| .Linit_done:
 | |
| 	/* Jump to main program entry point (argc = argv = envp = 0) */
 | |
| 	l.or	r3,r0,r0
 | |
| 	l.or	r4,r0,r0
 | |
| 	OR1K_DELAYED(
 | |
| 		OR1K_INST(l.or r5,r0,r0),
 | |
| 		OR1K_INST(l.jal main)
 | |
| 	)
 | |
| 
 | |
| #ifdef __OR1K_MULTICORE__
 | |
| .incrementexit:
 | |
| 	/* Atomically increment number of finished cores */
 | |
| 	l.lwa	r3,0x8(r0)
 | |
| 	l.addi	r3,r3,1
 | |
| 	l.swa	0x8(r0),r3
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.bnf .incrementexit));
 | |
| 	/* Compare to number of cores in this cluster */
 | |
| 	l.mfspr	r4,r0, OR1K_SPR_SYS_NUMCORES_ADDR
 | |
| 	/* Compare to number of finished tasks */
 | |
| 	l.sfeq	r3,r4
 | |
| 	/* Last core needs to desctruct library etc. */
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.bf .exitcorelast));
 | |
| 	OR1K_DELAYED(
 | |
| 		OR1K_INST(l.addi r3,r11,0),
 | |
| 		OR1K_INST(l.jal _exit)
 | |
| 	)
 | |
| .exitcorelast:
 | |
| #endif
 | |
| 	/* If program exits, call exit routine */
 | |
| 	OR1K_DELAYED(
 | |
| 		OR1K_INST(l.addi r3,r11,0),
 | |
| 		OR1K_INST(l.jal exit)
 | |
| 	)
 | |
| 
 | |
| 	/* Loop forever */
 | |
| .Lloop_forever:
 | |
| 	OR1K_DELAYED_NOP(OR1K_INST(l.j .Lloop_forever))
 | |
| 
 | |
| 	.size _or1k_start,.-_or1k_start
 |