new files submitted by Craig Lebakken (lebakken@minn.net) and Derrick Ostertag

(ostertag@transition.com)

1 files changed, 288 insertions, 0 deletions

diff --git a/c/src/lib/start/a29k/crt0.s b/c/src/lib/start/a29k/crt0.s
new file mode 100644
index 0000000000..017f2d4cca
--- /dev/null
+++ b/c/src/lib/start/a29k/crt0.s
@@ -0,0 +1,288 @@
+; @(#)crt0.s	1.3 96/05/31 14:40:27, AMD
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; Copyright 1988, 1989, 1990 Advanced Micro Devices, Inc.
+;
+; This software is the property of Advanced Micro Devices, Inc	(AMD)  which
+; specifically	grants the user the right to modify, use and distribute this
+; software provided this notice is not removed or altered.  All other rights
+; are reserved by AMD.
+;
+; AMD MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS
+; SOFTWARE.  IN NO EVENT SHALL AMD BE LIABLE FOR INCIDENTAL OR CONSEQUENTIAL
+; DAMAGES IN CONNECTION WITH OR ARISING FROM THE FURNISHING, PERFORMANCE, OR
+; USE OF THIS SOFTWARE.
+;
+; So that all may benefit from your experience, please report  any  problems
+; or  suggestions about this software to the 29K Technical Support Center at
+; 800-29-29-AMD (800-292-9263) in the USA, or 0800-89-1131  in	the  UK,  or
+; 0031-11-1129 in Japan, toll free.  The direct dial number is 512-462-4118.
+;
+; Advanced Micro Devices, Inc.
+; 29K Support Products
+; Mail Stop 573
+; 5900 E. Ben White Blvd.
+; Austin, TX 78741
+; 800-292-9263
+;
+;  /* $Id$ */
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+	.file	"crt0.s"
+
+; crt0.s version 3.3-0
+;
+; This module gets control from the OS.
+; It saves away the Am29027 Mode register settings and
+; then sets up the pointers to the resident spill and fill
+; trap handlers. It then establishes argv and argc for passing
+; to main. It then calls _main. If main returns, it calls _exit.
+;
+;	void = start( );
+;	NOTE - not C callable (no lead underscore)
+;
+	.include	"sysmac.h"
+;
+;
+	.extern V_SPILL, V_FILL
+;	.comm	__29027Mode, 8	; A shadow of the mode register
+	.comm	__LibInit, 4
+
+	.text
+	.extern _main, _exit, _atexit
+
+	.word	0			; Terminating tag word
+	.global start
+start:
+	sub	gr1, gr1, 6 * 4
+	asgeu	V_SPILL, gr1, rab	; better not ever happen
+	add	lr1, gr1, 6 * 4
+
+;
+; Save the initial value of the Am29027's Mode register
+;
+; If your system does not enter crt0 with value for Am29027's Mode 
+; register in gr96 and gr97, and also the coprocessor is active 
+; uncomment the next 4 instructions.
+;
+;	const	gr96, 0xfc00820
+;	consth	gr96, 0xfc00820
+;	const	gr97, 0x1375
+;	store	1, 3, gr96, gr97
+;
+;	const	gr98, __29027Mode
+;	consth	gr98, __29027Mode
+;	store	0, 0, gr96, gr98
+;	add	gr98, gr98, 4
+;	store	0, 0, gr97, gr98
+;
+; Now call the system to setup the spill and fill trap handlers
+;
+	const	lr3, spill
+	consth	lr3, spill
+	const	lr2, V_SPILL
+	syscall setvec
+	const	lr3, fill
+	consth	lr3, fill
+	const	lr2, V_FILL
+	syscall setvec
+
+;
+; atexit(_fini)
+;
+;        const   lr0, _atexit
+;        consth  lr0, _atexit
+;        const   lr2,__fini
+;        calli   lr0,lr0
+;        consth  lr2,__fini
+;
+; Now call _init
+;
+;        const   lr0, __init
+;        consth  lr0, __init
+;        calli   lr0,lr0
+;        nop
+
+;
+; Get the argv base address and calculate argc.
+;
+	syscall getargs
+	add	lr3, v0, 0		; argv
+	add	lr4, v0, 0
+	constn	lr2, -1
+argcloop:				; scan for NULL terminator
+	load	0, 0, gr97, lr4
+	add	lr4, lr4, 4
+	cpeq	gr97, gr97, 0
+	jmpf	gr97, argcloop
+	add	lr2, lr2, 1
+;
+; Now call LibInit, if there is one. To aid runtime libraries
+; that need to do some startup initialization, we have created
+; a bss variable called LibInit. If the library doesn't need
+; any run-time initialization, the variable is still 0. If the
+; library does need run-time initialization, the library will
+; contain a definition like
+; void (*_LibInit)(void) = LibInitFunction;
+; The linker will match up our bss LibInit with this data LibInit
+; and the variable will not be 0.  This results in the LibInit routine
+; being called via the calli instruction below.
+;
+	const	lr0, __LibInit
+	consth	lr0, __LibInit
+	load	0, 0, lr0, lr0
+	cpeq	gr96, lr0, 0
+	jmpt	gr96, NoLibInit
+	nop
+	calli	lr0, lr0
+	nop
+NoLibInit:
+
+;
+; Call RAMInit to initialize the data memory.
+; 
+; The following code segment was used to create the two flavors of the 
+; run-time initialization routines (crt0_1.o, and crt0_2.o) as described
+; in the User's Manual.  If osboot is used to create a stand-alone
+; application, or the call to RAMInit is made in the start-up routine, 
+; then the following is not needed.
+;
+;       .ifdef ROM_LOAD
+;       .extern RAMInit
+;
+;       const   lr0, RAMInit
+;       consth  lr0, RAMInit
+;       calli   gr96, lr0
+;       nop
+;       .else
+;       nop
+;       nop
+;       nop
+;       nop
+;       .endif
+
+;
+; Uncomment the following .comm, if you ARE NOT using osboot as released
+; with the High C 29K product, AND plan to use the romcoff utility to
+; move code and/or data sections to ROM.
+;
+;       .comm   RAMInit, 4
+; 
+; Furthermore, if the above is uncommented, then use the following logic
+; to call the RAMInit function, if needed.  
+;
+;       const   lr0, RAMInit
+;       consth  lr0, RAMInit
+;       load    0, 0, gr96, lr0
+;       cpeq    gr96, gr96, 0           ; nothing there?
+;       jmpt    gr96, endRAMInit        ; yes, nothing to init
+;       nop
+;       calli   gr96, lr0               ; no, then instruction found
+;       nop                             ; execute function.
+;
+
+
+;
+; call main, passing it 2 arguments. main( argc, argv )
+;
+	const	lr0, _main
+	consth	lr0, _main
+	calli	lr0, lr0
+	nop
+;
+; call exit
+;
+	const	lr0, _exit
+	consth	lr0, _exit
+	calli	lr0, lr0
+	add	lr2, gr96, 0
+;
+; Should never get here, but just in case
+;
+loop:
+	syscall exit
+	jmp	loop
+	nop
+	.sbttl	"Spill and Fill trap handlers"
+	.eject
+;
+;	SPILL, FILL trap handlers
+;
+; Note that these Spill and Fill trap handlers allow the OS to
+; assume that the only registers of use are between gr1 and rfb.
+; Therefore, if the OS desires to, it may simply preserve from
+; lr0 for (rfb-gr1)/4 registers when doing a context save.
+;
+;
+; Here is the spill handler
+;
+; spill registers from [*gr1..*rab)
+; and move rab downto where gr1 points
+;
+; rab must change before rfb for signals to work
+;
+; On entry:	rfb - rab = windowsize, gr1 < rab
+; Near the end: rfb - rab > windowsize, gr1 == rab
+; On exit:	rfb - rab = windowsize, gr1 == rab
+;
+	.global spill
+spill:
+	sub	tav, rab, gr1	; tav = number of bytes to spill
+	srl	tav, tav, 2	; change byte count to word count
+	sub	tav, tav, 1	; make count zero based
+	mtsr	CR, tav		; set Count Remaining register
+	sub	tav, rab, gr1
+	sub	tav, rfb, tav	; pull down free bound and save it in rab
+	add	rab, gr1, 0	; first pull down allocate bound
+	storem	0, 0, lr0, tav	; store lr0..lr(tav) into rfb
+	jmpi	tpc		; return...
+	add	rfb, tav, 0
+;
+; Here is the fill handler
+;
+; fill registers from [*rfb..*lr1)
+; and move rfb upto where lr1 points.
+;
+; rab must change before rfb for signals to work
+;
+; On entry:	rfb - rab = windowsize, lr1 > rfb
+; Near the end: rfb - rab < windowsize, lr1 == rab + windowsize
+; On exit:	rfb - rab = windowsize, lr1 == rfb
+;
+	.global fill
+fill:
+	const	tav, 0x80 << 2
+	or	tav, tav, rfb	; tav = ((rfb>>2) | 0x80)<<2 == [rfb]<<2
+	mtsr	IPA, tav	; ipa = [rfb]<<2 == 1st reg to fill
+				; gr0 is now the first reg to fill
+	sub	tav, lr1, rfb	; tav = number of bytes to fill
+	add	rab, rab, tav	; push up allocate bound
+	srl	tav, tav, 2	; change byte count to word count
+	sub	tav, tav, 1	; make count zero based
+	mtsr	CR, tav		; set Count Remaining register
+	loadm	0, 0, gr0, rfb	; load registers
+	jmpi	tpc		; return...
+	add	rfb, lr1, 0	; ... first pushing up free bound
+
+;
+; The __init function
+;
+;        .sect   .init,text
+;        .use .init
+;        .global __init
+;__init:
+;        sub     gr1,gr1,16
+;        asgeu   V_SPILL,gr1,gr126
+;        add     lr1,gr1,24
+;
+;
+; The __fini function
+;
+;        .sect   .fini,text
+;        .use .fini
+;        .global __fini
+;__fini:
+;        sub     gr1,gr1,16
+;        asgeu   V_SPILL,gr1,gr126
+;        add     lr1,gr1,24
+;
+	.end