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178 lines
4.6 KiB
ArmAsm
178 lines
4.6 KiB
ArmAsm
/*
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* pmon.S -- low-level entry points into PMON monitor.
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*
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* Copyright (c) 1996, 1997, 2002 Cygnus Support
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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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#ifdef __mips16
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/* This file contains 32 bit assembly code. */
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.set nomips16
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#endif
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#if !defined(__mips64)
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/* This machine does not support 64-bit operations. */
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#define ADDU addu
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#define SUBU subu
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#else
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/* This machine supports 64-bit operations. */
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#define ADDU daddu
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#define SUBU dsubu
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#endif
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#include "regs.S"
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.text
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.align 2
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#ifdef LSI
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#define PMON_VECTOR 0xffffffffbfc00200
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#else
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#define PMON_VECTOR 0xffffffffbfc00500
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#endif
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#ifndef __mips_eabi
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/* Provide named functions for entry into the monitor: */
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#define INDIRECT(name,index) \
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.globl name; \
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.ent name; \
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.set noreorder; \
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name: la $2,+(PMON_VECTOR+((index)*4)); \
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lw $2,0($2); \
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j $2; \
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nop; \
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.set reorder; \
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.end name
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#else
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#define INDIRECT(name,index) \
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.globl name; \
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.ent name; \
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.set noreorder; \
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name: la $2,+(PMON_VECTOR+((index)*4)); \
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lw $2,0($2); \
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SUBU sp,sp,0x40; \
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sd ra,0x38(sp); \
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sd fp,0x30(sp); \
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jal $2; \
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move fp,sp; \
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ld ra,0x38(sp); \
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ld fp,0x30(sp); \
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j ra; \
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ADDU sp,sp,0x40; \
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.set reorder; \
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.end name
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#endif
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/* The following magic numbers are for the slots into the PMON monitor */
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/* The first are used as the lo-level library run-time: */
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INDIRECT(read,0)
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INDIRECT(write,1)
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INDIRECT(open,2)
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INDIRECT(close,3)
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/* The following are useful monitor routines: */
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INDIRECT(mon_ioctl,4)
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INDIRECT(mon_printf,5)
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INDIRECT(mon_vsprintf,6)
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INDIRECT(mon_ttctl,7)
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INDIRECT(mon_cliexit,8)
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INDIRECT(mon_getenv,9)
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INDIRECT(mon_onintr,10)
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INDIRECT(mon_flush_cache,11)
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INDIRECT(_flush_cache,11)
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INDIRECT(mon_exception,12)
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/* The following routine is required by the "print()" function: */
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.globl outbyte
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.ent outbyte
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.set noreorder
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outbyte:
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subu sp,sp,0x20 /* allocate stack space for string */
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sd ra,0x18(sp) /* stack return address */
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sd fp,0x10(sp) /* stack frame-pointer */
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move fp,sp /* take a copy of the stack pointer */
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/* We leave so much space on the stack for the string (16
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characters), since the call to mon_printf seems to corrupt
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the 8bytes at offset 8 into the string/stack. */
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sb a0,0x00(sp) /* character to print */
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sb z0,0x01(sp) /* NUL terminator */
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jal mon_printf /* and output the string */
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move a0,sp /* take a copy of the string pointer {DELAY SLOT} */
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move sp,fp /* recover stack pointer */
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ld ra,0x18(sp) /* recover return address */
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ld fp,0x10(sp) /* recover frame-pointer */
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j ra /* return to the caller */
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addu sp,sp,0x20 /* dump the stack space {DELAY SLOT} */
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.set reorder
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.end outbyte
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/* The following routine is required by the "sbrk()" function: */
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.globl get_mem_info
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.ent get_mem_info
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.set noreorder
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get_mem_info:
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# in: a0 = pointer to 3 word structure
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# out: void
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subu sp,sp,0x18 /* create some stack space */
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sd ra,0x00(sp) /* stack return address */
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sd fp,0x08(sp) /* stack frame-pointer */
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sd a0,0x10(sp) /* stack structure pointer */
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move fp,sp /* take a copy of the stack pointer */
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# The monitor has already sized memory, but unfortunately we
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# do not have access to the data location containing the
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# memory size.
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jal __sizemem
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nop
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ld a0,0x10(sp) # recover structure pointer
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sw v0,0(a0) # amount of memory available
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# Deal with getting the cache size information:
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mfc0 a1, C0_CONFIG
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nop
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nop
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andi a2,a1,0x7 << 9 # bits 11..9 for instruction cache size
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sll a2,a2,12 - 8
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sw a2,4(a0)
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andi a2,a1,0x7 << 6 # bits 8..6 for data cache size
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sll a2,a2,12 - 5
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sw a2,8(a0) # data cache size
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#
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move sp,fp /* recover stack pointer */
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ld ra,0x00(sp) /* recover return address */
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ld fp,0x08(sp) /* recover frame-pointer */
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j ra /* return to the caller */
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addu sp,sp,0x18 /* restore stack pointer {DELAY SLOT} */
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.set reorder
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.end get_mem_info
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#ifdef LSI
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# For the LSI MiniRISC board, we can safely assume that we have
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# at least one megabyte of RAM.
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.globl __sizemem
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.ent __sizemem
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__sizemem:
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li v0,0x100000
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j ra
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.end __sizemem
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#else
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#endif
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/* EOF pmon.S */
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