xref: /linux/arch/sparc/kernel/head_32.S (revision 71ca97da9d027009d318d319cbacf54a72f666c1)
1/*
2 * head.S: The initial boot code for the Sparc port of Linux.
3 *
4 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
5 * Copyright (C) 1995,1999 Pete Zaitcev   (zaitcev@yahoo.com)
6 * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
7 * Copyright (C) 1997 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
8 * Copyright (C) 1997 Michael A. Griffith (grif@acm.org)
9 *
10 * CompactPCI platform by Eric Brower, 1999.
11 */
12
13#include <linux/version.h>
14#include <linux/init.h>
15
16#include <asm/head.h>
17#include <asm/asi.h>
18#include <asm/contregs.h>
19#include <asm/ptrace.h>
20#include <asm/psr.h>
21#include <asm/page.h>
22#include <asm/kdebug.h>
23#include <asm/winmacro.h>
24#include <asm/thread_info.h>	/* TI_UWINMASK */
25#include <asm/errno.h>
26#include <asm/pgtsrmmu.h>	/* SRMMU_PGDIR_SHIFT */
27
28	.data
29/* The following are used with the prom_vector node-ops to figure out
30 * the cpu-type
31 */
32	.align 4
33cputyp:
34        .word   1
35
36	.align 4
37	.globl cputypval
38cputypval:
39	.asciz "sun4m"
40	.ascii "     "
41
42/* Tested on SS-5, SS-10 */
43	.align 4
44cputypvar:
45	.asciz "compatible"
46
47	.align 4
48
49sun4c_notsup:
50	.asciz	"Sparc-Linux sun4/sun4c support does no longer exist.\n\n"
51	.align 4
52
53sun4e_notsup:
54        .asciz  "Sparc-Linux sun4e support does not exist\n\n"
55	.align 4
56
57/* The trap-table - located in the __HEAD section */
58#include "ttable_32.S"
59
60	.align PAGE_SIZE
61
62/* This was the only reasonable way I could think of to properly align
63 * these page-table data structures.
64 */
65	.globl swapper_pg_dir
66swapper_pg_dir:		.skip PAGE_SIZE
67	.globl empty_zero_page
68empty_zero_page:	.skip PAGE_SIZE
69
70	.global root_flags
71	.global ram_flags
72	.global root_dev
73	.global sparc_ramdisk_image
74	.global sparc_ramdisk_size
75
76/* This stuff has to be in sync with SILO and other potential boot loaders
77 * Fields should be kept upward compatible and whenever any change is made,
78 * HdrS version should be incremented.
79 */
80	.ascii	"HdrS"
81	.word	LINUX_VERSION_CODE
82	.half	0x0203		/* HdrS version */
83root_flags:
84	.half	1
85root_dev:
86	.half	0
87ram_flags:
88	.half	0
89sparc_ramdisk_image:
90	.word	0
91sparc_ramdisk_size:
92	.word	0
93	.word	reboot_command
94	.word	0, 0, 0
95	.word	_end
96
97/* Cool, here we go. Pick up the romvec pointer in %o0 and stash it in
98 * %g7 and at prom_vector_p. And also quickly check whether we are on
99 * a v0, v2, or v3 prom.
100 */
101gokernel:
102		/* Ok, it's nice to know, as early as possible, if we
103		 * are already mapped where we expect to be in virtual
104		 * memory.  The Solaris /boot elf format bootloader
105		 * will peek into our elf header and load us where
106		 * we want to be, otherwise we have to re-map.
107		 *
108		 * Some boot loaders don't place the jmp'rs address
109		 * in %o7, so we do a pc-relative call to a local
110		 * label, then see what %o7 has.
111		 */
112
113		mov	%o7, %g4		! Save %o7
114
115		/* Jump to it, and pray... */
116current_pc:
117		call	1f
118		 nop
119
1201:
121		mov	%o7, %g3
122
123		tst	%o0
124		be	no_sun4u_here
125		 mov	%g4, %o7		/* Previous %o7. */
126
127		mov	%o0, %l0		! stash away romvec
128		mov	%o0, %g7		! put it here too
129		mov	%o1, %l1		! stash away debug_vec too
130
131		/* Ok, let's check out our run time program counter. */
132		set	current_pc, %g5
133		cmp	%g3, %g5
134		be	already_mapped
135		 nop
136
137		/* %l6 will hold the offset we have to subtract
138		 * from absolute symbols in order to access areas
139		 * in our own image.  If already mapped this is
140		 * just plain zero, else it is KERNBASE.
141		 */
142		set	KERNBASE, %l6
143		b	copy_prom_lvl14
144		 nop
145
146already_mapped:
147		mov	0, %l6
148
149		/* Copy over the Prom's level 14 clock handler. */
150copy_prom_lvl14:
151#if 1
152		/* DJHR
153		 * preserve our linked/calculated instructions
154		 */
155		set	lvl14_save, %g1
156		set	t_irq14, %g3
157		sub	%g1, %l6, %g1		! translate to physical
158		sub	%g3, %l6, %g3		! translate to physical
159		ldd	[%g3], %g4
160		std	%g4, [%g1]
161		ldd	[%g3+8], %g4
162		std	%g4, [%g1+8]
163#endif
164		rd	%tbr, %g1
165		andn	%g1, 0xfff, %g1		! proms trap table base
166		or	%g0, (0x1e<<4), %g2	! offset to lvl14 intr
167		or	%g1, %g2, %g2
168		set	t_irq14, %g3
169		sub	%g3, %l6, %g3
170		ldd	[%g2], %g4
171		std	%g4, [%g3]
172		ldd	[%g2 + 0x8], %g4
173		std	%g4, [%g3 + 0x8]	! Copy proms handler
174
175/* DON'T TOUCH %l0 thru %l5 in these remapping routines,
176 * we need their values afterwards!
177 */
178
179		/* Now check whether we are already mapped, if we
180		 * are we can skip all this garbage coming up.
181		 */
182copy_prom_done:
183		cmp	%l6, 0
184		be	go_to_highmem		! this will be a nop then
185		 nop
186
187		/* Validate that we are in fact running on an
188		 * SRMMU based cpu.
189		 */
190		set	0x4000, %g6
191		cmp	%g7, %g6
192		bne	not_a_sun4
193		 nop
194
195halt_sun4_or_sun4c:
196		ld	[%g7 + 0x68], %o1
197		set	sun4c_notsup, %o0
198		sub	%o0, %l6, %o0
199		call	%o1
200		 nop
201		ba	halt_me
202		 nop
203
204not_a_sun4:
205		lda	[%g0] ASI_M_MMUREGS, %g1
206		andcc	%g1, 1, %g0
207		be	halt_sun4_or_sun4c
208		 nop
209
210srmmu_remap:
211		/* First, check for a viking (TI) module. */
212		set	0x40000000, %g2
213		rd	%psr, %g3
214		and	%g2, %g3, %g3
215		subcc	%g3, 0x0, %g0
216		bz	srmmu_nviking
217		 nop
218
219		/* Figure out what kind of viking we are on.
220		 * We need to know if we have to play with the
221		 * AC bit and disable traps or not.
222		 */
223
224		/* I've only seen MicroSparc's on SparcClassics with this
225		 * bit set.
226		 */
227		set	0x800, %g2
228		lda	[%g0] ASI_M_MMUREGS, %g3	! peek in the control reg
229		and	%g2, %g3, %g3
230		subcc	%g3, 0x0, %g0
231		bnz	srmmu_nviking			! is in mbus mode
232		 nop
233
234		rd	%psr, %g3			! DO NOT TOUCH %g3
235		andn	%g3, PSR_ET, %g2
236		wr	%g2, 0x0, %psr
237		WRITE_PAUSE
238
239		/* Get context table pointer, then convert to
240		 * a physical address, which is 36 bits.
241		 */
242		set	AC_M_CTPR, %g4
243		lda	[%g4] ASI_M_MMUREGS, %g4
244		sll	%g4, 0x4, %g4			! We use this below
245							! DO NOT TOUCH %g4
246
247		/* Set the AC bit in the Viking's MMU control reg. */
248		lda	[%g0] ASI_M_MMUREGS, %g5	! DO NOT TOUCH %g5
249		set	0x8000, %g6			! AC bit mask
250		or	%g5, %g6, %g6			! Or it in...
251		sta	%g6, [%g0] ASI_M_MMUREGS	! Close your eyes...
252
253		/* Grrr, why does it seem like every other load/store
254		 * on the sun4m is in some ASI space...
255		 * Fine with me, let's get the pointer to the level 1
256		 * page table directory and fetch its entry.
257		 */
258		lda	[%g4] ASI_M_BYPASS, %o1		! This is a level 1 ptr
259		srl	%o1, 0x4, %o1			! Clear low 4 bits
260		sll	%o1, 0x8, %o1			! Make physical
261
262		/* Ok, pull in the PTD. */
263		lda	[%o1] ASI_M_BYPASS, %o2		! This is the 0x0 16MB pgd
264
265		/* Calculate to KERNBASE entry. */
266		add	%o1, KERNBASE >> (SRMMU_PGDIR_SHIFT - 2), %o3
267
268		/* Poke the entry into the calculated address. */
269		sta	%o2, [%o3] ASI_M_BYPASS
270
271		/* I don't get it Sun, if you engineered all these
272		 * boot loaders and the PROM (thank you for the debugging
273		 * features btw) why did you not have them load kernel
274		 * images up in high address space, since this is necessary
275		 * for ABI compliance anyways?  Does this low-mapping provide
276		 * enhanced interoperability?
277		 *
278		 * "The PROM is the computer."
279		 */
280
281		/* Ok, restore the MMU control register we saved in %g5 */
282		sta	%g5, [%g0] ASI_M_MMUREGS	! POW... ouch
283
284		/* Turn traps back on.  We saved it in %g3 earlier. */
285		wr	%g3, 0x0, %psr			! tick tock, tick tock
286
287		/* Now we burn precious CPU cycles due to bad engineering. */
288		WRITE_PAUSE
289
290		/* Wow, all that just to move a 32-bit value from one
291		 * place to another...  Jump to high memory.
292		 */
293		b	go_to_highmem
294		 nop
295
296		/* This works on viking's in Mbus mode and all
297		 * other MBUS modules.  It is virtually the same as
298		 * the above madness sans turning traps off and flipping
299		 * the AC bit.
300		 */
301srmmu_nviking:
302		set	AC_M_CTPR, %g1
303		lda	[%g1] ASI_M_MMUREGS, %g1	! get ctx table ptr
304		sll	%g1, 0x4, %g1			! make physical addr
305		lda	[%g1] ASI_M_BYPASS, %g1		! ptr to level 1 pg_table
306		srl	%g1, 0x4, %g1
307		sll	%g1, 0x8, %g1			! make phys addr for l1 tbl
308
309		lda	[%g1] ASI_M_BYPASS, %g2		! get level1 entry for 0x0
310		add	%g1, KERNBASE >> (SRMMU_PGDIR_SHIFT - 2), %g3
311		sta	%g2, [%g3] ASI_M_BYPASS		! place at KERNBASE entry
312		b	go_to_highmem
313		 nop					! wheee....
314
315
316/* Now do a non-relative jump so that PC is in high-memory */
317go_to_highmem:
318		set	execute_in_high_mem, %g1
319		jmpl	%g1, %g0
320		 nop
321
322/* The code above should be at beginning and we have to take care about
323 * short jumps, as branching to .init.text section from .text is usually
324 * impossible */
325		__INIT
326/* Acquire boot time privileged register values, this will help debugging.
327 * I figure out and store nwindows and nwindowsm1 later on.
328 */
329execute_in_high_mem:
330		mov	%l0, %o0		! put back romvec
331		mov	%l1, %o1		! and debug_vec
332
333		sethi	%hi(prom_vector_p), %g1
334		st	%o0, [%g1 + %lo(prom_vector_p)]
335
336		sethi	%hi(linux_dbvec), %g1
337		st	%o1, [%g1 + %lo(linux_dbvec)]
338
339/* Get the machine type via the mysterious romvec node operations. */
340
341		add	%g7, 0x1c, %l1
342		ld	[%l1], %l0
343		ld	[%l0], %l0
344		call	%l0
345		 or	%g0, %g0, %o0		! next_node(0) = first_node
346		or	%o0, %g0, %g6
347
348		sethi	%hi(cputypvar), %o1	! First node has cpu-arch
349		or	%o1, %lo(cputypvar), %o1
350		sethi	%hi(cputypval), %o2	! information, the string
351		or	%o2, %lo(cputypval), %o2
352		ld	[%l1], %l0		! 'compatible' tells
353		ld	[%l0 + 0xc], %l0	! that we want 'sun4x' where
354		call	%l0			! x is one of 'm', 'd' or 'e'.
355		 nop				! %o2 holds pointer
356						! to a buf where above string
357						! will get stored by the prom.
358
359#ifdef CONFIG_SPARC_LEON
360	        /* no cpu-type check is needed, it is a SPARC-LEON */
361
362		sethi	%hi(boot_cpu_id), %g2	! boot-cpu index
363
364#ifdef CONFIG_SMP
365		ldub	[%g2 + %lo(boot_cpu_id)], %g1
366		cmp	%g1, 0xff		! unset means first CPU
367		bne	leon_smp_cpu_startup	! continue only with master
368		 nop
369#endif
370		/* Get CPU-ID from most significant 4-bit of ASR17 */
371		rd     %asr17, %g1
372		srl    %g1, 28, %g1
373
374		/* Update boot_cpu_id only on boot cpu */
375		stub	%g1, [%g2 + %lo(boot_cpu_id)]
376
377		ba continue_boot
378		 nop
379#endif
380
381/* Check to cputype. We may be booted on a sun4u (64 bit box),
382 * and sun4d needs special treatment.
383 */
384
385		set	cputypval, %o2
386		ldub	[%o2 + 0x4], %l1
387
388		cmp	%l1, 'm'
389		be	sun4m_init
390		 cmp	%l1, 's'
391		be	sun4m_init
392		 cmp	%l1, 'd'
393		be	sun4d_init
394		 cmp	%l1, 'e'
395		be	no_sun4e_here		! Could be a sun4e.
396		 nop
397		b	no_sun4u_here		! AIEEE, a V9 sun4u... Get our BIG BROTHER kernel :))
398		 nop
399
400/* CPUID in bootbus can be found at PA 0xff0140000 */
401#define SUN4D_BOOTBUS_CPUID     0xf0140000
402
403sun4d_init:
404	/* Need to patch call to handler_irq */
405	set	patch_handler_irq, %g4
406	set	sun4d_handler_irq, %g5
407	sethi	%hi(0x40000000), %g3		! call
408	sub	%g5, %g4, %g5
409	srl	%g5, 2, %g5
410	or	%g5, %g3, %g5
411	st	%g5, [%g4]
412
413#ifdef CONFIG_SMP
414	/* Get our CPU id out of bootbus */
415	set     SUN4D_BOOTBUS_CPUID, %g3
416	lduba   [%g3] ASI_M_CTL, %g3
417	and     %g3, 0xf8, %g3
418	srl     %g3, 3, %g4
419	sta     %g4, [%g0] ASI_M_VIKING_TMP1
420	sethi	%hi(boot_cpu_id), %g5
421	stb	%g4, [%g5 + %lo(boot_cpu_id)]
422#endif
423
424	/* Fall through to sun4m_init */
425
426sun4m_init:
427/* Ok, the PROM could have done funny things and apple cider could still
428 * be sitting in the fault status/address registers.  Read them all to
429 * clear them so we don't get magic faults later on.
430 */
431/* This sucks, apparently this makes Vikings call prom panic, will fix later */
4322:
433		rd	%psr, %o1
434		srl	%o1, 28, %o1		! Get a type of the CPU
435
436		subcc	%o1, 4, %g0		! TI: Viking or MicroSPARC
437		be	continue_boot
438		 nop
439
440		set	AC_M_SFSR, %o0
441		lda	[%o0] ASI_M_MMUREGS, %g0
442		set	AC_M_SFAR, %o0
443		lda	[%o0] ASI_M_MMUREGS, %g0
444
445		/* Fujitsu MicroSPARC-II has no asynchronous flavors of FARs */
446		subcc	%o1, 0, %g0
447		be	continue_boot
448		 nop
449
450		set	AC_M_AFSR, %o0
451		lda	[%o0] ASI_M_MMUREGS, %g0
452		set	AC_M_AFAR, %o0
453		lda	[%o0] ASI_M_MMUREGS, %g0
454		 nop
455
456
457continue_boot:
458
459/* Aieee, now set PC and nPC, enable traps, give ourselves a stack and it's
460 * show-time!
461 */
462
463		sethi	%hi(cputyp), %o0
464		st	%g4, [%o0 + %lo(cputyp)]
465
466		/* Turn on Supervisor, EnableFloating, and all the PIL bits.
467		 * Also puts us in register window zero with traps off.
468		 */
469		set	(PSR_PS | PSR_S | PSR_PIL | PSR_EF), %g2
470		wr	%g2, 0x0, %psr
471		WRITE_PAUSE
472
473		/* I want a kernel stack NOW! */
474		set	init_thread_union, %g1
475		set	(THREAD_SIZE - STACKFRAME_SZ), %g2
476		add	%g1, %g2, %sp
477		mov	0, %fp			/* And for good luck */
478
479		/* Zero out our BSS section. */
480		set	__bss_start , %o0	! First address of BSS
481		set	_end , %o1		! Last address of BSS
482		add	%o0, 0x1, %o0
4831:
484		stb	%g0, [%o0]
485		subcc	%o0, %o1, %g0
486		bl	1b
487		 add	%o0, 0x1, %o0
488
489		/* If boot_cpu_id has not been setup by machine specific
490		 * init-code above we default it to zero.
491		 */
492		sethi	%hi(boot_cpu_id), %g2
493		ldub	[%g2 + %lo(boot_cpu_id)], %g3
494		cmp	%g3, 0xff
495		bne	1f
496		 nop
497		mov	%g0, %g3
498		stub	%g3, [%g2 + %lo(boot_cpu_id)]
499
5001:		sll	%g3, 2, %g3
501
502		/* Initialize the uwinmask value for init task just in case.
503		 * But first make current_set[boot_cpu_id] point to something useful.
504		 */
505		set	init_thread_union, %g6
506		set	current_set, %g2
507#ifdef CONFIG_SMP
508		st	%g6, [%g2]
509		add	%g2, %g3, %g2
510#endif
511		st	%g6, [%g2]
512
513		st	%g0, [%g6 + TI_UWINMASK]
514
515/* Compute NWINDOWS and stash it away. Now uses %wim trick explained
516 * in the V8 manual. Ok, this method seems to work, Sparc is cool...
517 * No, it doesn't work, have to play the save/readCWP/restore trick.
518 */
519
520		wr	%g0, 0x0, %wim			! so we do not get a trap
521		WRITE_PAUSE
522
523		save
524
525		rd	%psr, %g3
526
527		restore
528
529		and	%g3, 0x1f, %g3
530		add	%g3, 0x1, %g3
531
532		mov	2, %g1
533		wr	%g1, 0x0, %wim			! make window 1 invalid
534		WRITE_PAUSE
535
536		cmp	%g3, 0x7
537		bne	2f
538		 nop
539
540		/* Adjust our window handling routines to
541		 * do things correctly on 7 window Sparcs.
542		 */
543
544#define		PATCH_INSN(src, dest) \
545		set	src, %g5; \
546		set	dest, %g2; \
547		ld	[%g5], %g4; \
548		st	%g4, [%g2];
549
550		/* Patch for window spills... */
551		PATCH_INSN(spnwin_patch1_7win, spnwin_patch1)
552		PATCH_INSN(spnwin_patch2_7win, spnwin_patch2)
553		PATCH_INSN(spnwin_patch3_7win, spnwin_patch3)
554
555		/* Patch for window fills... */
556		PATCH_INSN(fnwin_patch1_7win, fnwin_patch1)
557		PATCH_INSN(fnwin_patch2_7win, fnwin_patch2)
558
559		/* Patch for trap entry setup... */
560		PATCH_INSN(tsetup_7win_patch1, tsetup_patch1)
561		PATCH_INSN(tsetup_7win_patch2, tsetup_patch2)
562		PATCH_INSN(tsetup_7win_patch3, tsetup_patch3)
563		PATCH_INSN(tsetup_7win_patch4, tsetup_patch4)
564		PATCH_INSN(tsetup_7win_patch5, tsetup_patch5)
565		PATCH_INSN(tsetup_7win_patch6, tsetup_patch6)
566
567		/* Patch for returning from traps... */
568		PATCH_INSN(rtrap_7win_patch1, rtrap_patch1)
569		PATCH_INSN(rtrap_7win_patch2, rtrap_patch2)
570		PATCH_INSN(rtrap_7win_patch3, rtrap_patch3)
571		PATCH_INSN(rtrap_7win_patch4, rtrap_patch4)
572		PATCH_INSN(rtrap_7win_patch5, rtrap_patch5)
573
574		/* Patch for killing user windows from the register file. */
575		PATCH_INSN(kuw_patch1_7win, kuw_patch1)
576
577		/* Now patch the kernel window flush sequences.
578		 * This saves 2 traps on every switch and fork.
579		 */
580		set	0x01000000, %g4
581		set	flush_patch_one, %g5
582		st	%g4, [%g5 + 0x18]
583		st	%g4, [%g5 + 0x1c]
584		set	flush_patch_two, %g5
585		st	%g4, [%g5 + 0x18]
586		st	%g4, [%g5 + 0x1c]
587		set	flush_patch_three, %g5
588		st	%g4, [%g5 + 0x18]
589		st	%g4, [%g5 + 0x1c]
590		set	flush_patch_four, %g5
591		st	%g4, [%g5 + 0x18]
592		st	%g4, [%g5 + 0x1c]
593		set	flush_patch_exception, %g5
594		st	%g4, [%g5 + 0x18]
595		st	%g4, [%g5 + 0x1c]
596		set	flush_patch_switch, %g5
597		st	%g4, [%g5 + 0x18]
598		st	%g4, [%g5 + 0x1c]
599
6002:
601		sethi	%hi(nwindows), %g4
602		st	%g3, [%g4 + %lo(nwindows)]	! store final value
603		sub	%g3, 0x1, %g3
604		sethi	%hi(nwindowsm1), %g4
605		st	%g3, [%g4 + %lo(nwindowsm1)]
606
607		/* Here we go, start using Linux's trap table... */
608		set	trapbase, %g3
609		wr	%g3, 0x0, %tbr
610		WRITE_PAUSE
611
612		/* Finally, turn on traps so that we can call c-code. */
613		rd	%psr, %g3
614		wr	%g3, 0x0, %psr
615		WRITE_PAUSE
616
617		wr	%g3, PSR_ET, %psr
618		WRITE_PAUSE
619
620		/* First we call prom_init() to set up PROMLIB, then
621		 * off to start_kernel().
622		 */
623
624		sethi	%hi(prom_vector_p), %g5
625		ld	[%g5 + %lo(prom_vector_p)], %o0
626		call	prom_init
627		 nop
628
629		call 	start_kernel
630		 nop
631
632		/* We should not get here. */
633		call	halt_me
634		 nop
635
636no_sun4e_here:
637		ld	[%g7 + 0x68], %o1
638		set	sun4e_notsup, %o0
639		call	%o1
640		 nop
641		b	halt_me
642		 nop
643
644		__INITDATA
645
646sun4u_1:
647		.asciz "finddevice"
648		.align	4
649sun4u_2:
650		.asciz "/chosen"
651		.align	4
652sun4u_3:
653		.asciz "getprop"
654		.align	4
655sun4u_4:
656		.asciz "stdout"
657		.align	4
658sun4u_5:
659		.asciz "write"
660		.align	4
661sun4u_6:
662        	.asciz  "\n\rOn sun4u you have to use UltraLinux (64bit) kernel\n\rand not a 32bit sun4[cdem] version\n\r\n\r"
663sun4u_6e:
664		.align	4
665sun4u_7:
666		.asciz "exit"
667		.align	8
668sun4u_a1:
669		.word	0, sun4u_1, 0, 1, 0, 1, 0, sun4u_2, 0
670sun4u_r1:
671		.word	0
672sun4u_a2:
673		.word	0, sun4u_3, 0, 4, 0, 1, 0
674sun4u_i2:
675		.word	0, 0, sun4u_4, 0, sun4u_1, 0, 8, 0
676sun4u_r2:
677		.word	0
678sun4u_a3:
679		.word	0, sun4u_5, 0, 3, 0, 1, 0
680sun4u_i3:
681		.word	0, 0, sun4u_6, 0, sun4u_6e - sun4u_6 - 1, 0
682sun4u_r3:
683		.word	0
684sun4u_a4:
685		.word	0, sun4u_7, 0, 0, 0, 0
686sun4u_r4:
687
688		__INIT
689no_sun4u_here:
690		set	sun4u_a1, %o0
691		set	current_pc, %l2
692		cmp	%l2, %g3
693		be	1f
694		 mov	%o4, %l0
695		sub	%g3, %l2, %l6
696		add	%o0, %l6, %o0
697		mov	%o0, %l4
698		mov	sun4u_r4 - sun4u_a1, %l3
699		ld	[%l4], %l5
7002:
701		add	%l4, 4, %l4
702		cmp	%l5, %l2
703		add	%l5, %l6, %l5
704		bgeu,a	3f
705		 st	%l5, [%l4 - 4]
7063:
707		subcc	%l3, 4, %l3
708		bne	2b
709		 ld	[%l4], %l5
7101:
711		call	%l0
712		 mov	%o0, %l1
713
714		ld	[%l1 + (sun4u_r1 - sun4u_a1)], %o1
715		add	%l1, (sun4u_a2 - sun4u_a1), %o0
716		call	%l0
717		 st	%o1, [%o0 + (sun4u_i2 - sun4u_a2)]
718
719		ld	[%l1 + (sun4u_1 - sun4u_a1)], %o1
720		add	%l1, (sun4u_a3 - sun4u_a1), %o0
721		call	%l0
722		st	%o1, [%o0 + (sun4u_i3 - sun4u_a3)]
723
724		call	%l0
725		 add	%l1, (sun4u_a4 - sun4u_a1), %o0
726
727		/* Not reached */
728halt_me:
729		ld	[%g7 + 0x74], %o0
730		call	%o0			! Get us out of here...
731		 nop				! Apparently Solaris is better.
732
733/* Ok, now we continue in the .data/.text sections */
734
735	.data
736	.align 4
737
738/*
739 * Fill up the prom vector, note in particular the kind first element,
740 * no joke. I don't need all of them in here as the entire prom vector
741 * gets initialized in c-code so all routines can use it.
742 */
743
744prom_vector_p:
745		.word 0
746
747/* We calculate the following at boot time, window fills/spills and trap entry
748 * code uses these to keep track of the register windows.
749 */
750
751	.align 4
752	.globl	nwindows
753	.globl	nwindowsm1
754nwindows:
755	.word	8
756nwindowsm1:
757	.word	7
758
759/* Boot time debugger vector value.  We need this later on. */
760
761	.align 4
762	.globl	linux_dbvec
763linux_dbvec:
764	.word	0
765	.word	0
766
767	.align 8
768
769	.globl	lvl14_save
770lvl14_save:
771	.word	0
772	.word	0
773	.word	0
774	.word	0
775	.word	t_irq14
776
777        .section        ".fixup",#alloc,#execinstr
778        .globl  __ret_efault
779__ret_efault:
780        ret
781         restore %g0, -EFAULT, %o0
782