1/*
2 * Copyright (C) 2004, 2005 MIPS Technologies, Inc.  All rights reserved.
3 *
4 *  This program is free software; you can distribute it and/or modify it
5 *  under the terms of the GNU General Public License (Version 2) as
6 *  published by the Free Software Foundation.
7 *
8 *  This program is distributed in the hope it will be useful, but WITHOUT
9 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
11 *  for more details.
12 *
13 *  You should have received a copy of the GNU General Public License along
14 *  with this program; if not, write to the Free Software Foundation, Inc.,
15 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
16 */
17
18/*
19 * VPE support module
20 *
21 * Provides support for loading a MIPS SP program on VPE1.
22 * The SP enviroment is rather simple, no tlb's.  It needs to be relocatable
23 * (or partially linked). You should initialise your stack in the startup
24 * code. This loader looks for the symbol __start and sets up
25 * execution to resume from there. The MIPS SDE kit contains suitable examples.
26 *
27 * To load and run, simply cat a SP 'program file' to /dev/vpe1.
28 * i.e cat spapp >/dev/vpe1.
29 */
30
31#include <linux/kernel.h>
32#include <linux/device.h>
33#include <linux/module.h>
34#include <linux/fs.h>
35#include <linux/init.h>
36#include <asm/uaccess.h>
37#include <linux/slab.h>
38#include <linux/list.h>
39#include <linux/vmalloc.h>
40#include <linux/elf.h>
41#include <linux/seq_file.h>
42#include <linux/syscalls.h>
43#include <linux/moduleloader.h>
44#include <linux/interrupt.h>
45#include <linux/poll.h>
46#include <linux/bootmem.h>
47#include <asm/mipsregs.h>
48#include <asm/mipsmtregs.h>
49#include <asm/cacheflush.h>
50#include <asm/atomic.h>
51#include <asm/cpu.h>
52#include <asm/mips_mt.h>
53#include <asm/processor.h>
54#include <asm/system.h>
55#include <asm/vpe.h>
56#include <asm/kspd.h>
57
58typedef void *vpe_handle;
59
60#ifndef ARCH_SHF_SMALL
61#define ARCH_SHF_SMALL 0
62#endif
63
64/* If this is set, the section belongs in the init part of the module */
65#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
66
67static char module_name[] = "vpe";
68static int major;
69static const int minor = 1;	/* fixed for now  */
70
71#ifdef CONFIG_MIPS_APSP_KSPD
72 static struct kspd_notifications kspd_events;
73static int kspd_events_reqd = 0;
74#endif
75
76/* grab the likely amount of memory we will need. */
77#ifdef CONFIG_MIPS_VPE_LOADER_TOM
78#define P_SIZE (2 * 1024 * 1024)
79#else
80/* add an overhead to the max kmalloc size for non-striped symbols/etc */
81#define P_SIZE (256 * 1024)
82#endif
83
84extern unsigned long physical_memsize;
85
86#define MAX_VPES 16
87#define VPE_PATH_MAX 256
88
89enum vpe_state {
90	VPE_STATE_UNUSED = 0,
91	VPE_STATE_INUSE,
92	VPE_STATE_RUNNING
93};
94
95enum tc_state {
96	TC_STATE_UNUSED = 0,
97	TC_STATE_INUSE,
98	TC_STATE_RUNNING,
99	TC_STATE_DYNAMIC
100};
101
102struct vpe {
103	enum vpe_state state;
104
105	/* (device) minor associated with this vpe */
106	int minor;
107
108	/* elfloader stuff */
109	void *load_addr;
110	unsigned long len;
111	char *pbuffer;
112	unsigned long plen;
113	unsigned int uid, gid;
114	char cwd[VPE_PATH_MAX];
115
116	unsigned long __start;
117
118	/* tc's associated with this vpe */
119	struct list_head tc;
120
121	/* The list of vpe's */
122	struct list_head list;
123
124	/* shared symbol address */
125	void *shared_ptr;
126
127	/* the list of who wants to know when something major happens */
128	struct list_head notify;
129};
130
131struct tc {
132	enum tc_state state;
133	int index;
134
135	/* parent VPE */
136	struct vpe *pvpe;
137
138	/* The list of TC's with this VPE */
139	struct list_head tc;
140
141	/* The global list of tc's */
142	struct list_head list;
143};
144
145struct {
146	/* Virtual processing elements */
147	struct list_head vpe_list;
148
149	/* Thread contexts */
150	struct list_head tc_list;
151} vpecontrol = {
152	.vpe_list = LIST_HEAD_INIT(vpecontrol.vpe_list),
153	.tc_list = LIST_HEAD_INIT(vpecontrol.tc_list)
154};
155
156static void release_progmem(void *ptr);
157/* static __attribute_used__ void dump_vpe(struct vpe * v); */
158extern void save_gp_address(unsigned int secbase, unsigned int rel);
159
160/* get the vpe associated with this minor */
161struct vpe *get_vpe(int minor)
162{
163	struct vpe *v;
164
165	if (!cpu_has_mipsmt)
166		return NULL;
167
168	list_for_each_entry(v, &vpecontrol.vpe_list, list) {
169		if (v->minor == minor)
170			return v;
171	}
172
173	return NULL;
174}
175
176/* get the vpe associated with this minor */
177struct tc *get_tc(int index)
178{
179	struct tc *t;
180
181	list_for_each_entry(t, &vpecontrol.tc_list, list) {
182		if (t->index == index)
183			return t;
184	}
185
186	return NULL;
187}
188
189struct tc *get_tc_unused(void)
190{
191	struct tc *t;
192
193	list_for_each_entry(t, &vpecontrol.tc_list, list) {
194		if (t->state == TC_STATE_UNUSED)
195			return t;
196	}
197
198	return NULL;
199}
200
201/* allocate a vpe and associate it with this minor (or index) */
202struct vpe *alloc_vpe(int minor)
203{
204	struct vpe *v;
205
206	if ((v = kzalloc(sizeof(struct vpe), GFP_KERNEL)) == NULL) {
207		return NULL;
208	}
209
210	INIT_LIST_HEAD(&v->tc);
211	list_add_tail(&v->list, &vpecontrol.vpe_list);
212
213	INIT_LIST_HEAD(&v->notify);
214	v->minor = minor;
215	return v;
216}
217
218/* allocate a tc. At startup only tc0 is running, all other can be halted. */
219struct tc *alloc_tc(int index)
220{
221	struct tc *t;
222
223	if ((t = kzalloc(sizeof(struct tc), GFP_KERNEL)) == NULL) {
224		return NULL;
225	}
226
227	INIT_LIST_HEAD(&t->tc);
228	list_add_tail(&t->list, &vpecontrol.tc_list);
229
230	t->index = index;
231
232	return t;
233}
234
235/* clean up and free everything */
236void release_vpe(struct vpe *v)
237{
238	list_del(&v->list);
239	if (v->load_addr)
240		release_progmem(v);
241	kfree(v);
242}
243
244void dump_mtregs(void)
245{
246	unsigned long val;
247
248	val = read_c0_config3();
249	printk("config3 0x%lx MT %ld\n", val,
250	       (val & CONFIG3_MT) >> CONFIG3_MT_SHIFT);
251
252	val = read_c0_mvpcontrol();
253	printk("MVPControl 0x%lx, STLB %ld VPC %ld EVP %ld\n", val,
254	       (val & MVPCONTROL_STLB) >> MVPCONTROL_STLB_SHIFT,
255	       (val & MVPCONTROL_VPC) >> MVPCONTROL_VPC_SHIFT,
256	       (val & MVPCONTROL_EVP));
257
258	val = read_c0_mvpconf0();
259	printk("mvpconf0 0x%lx, PVPE %ld PTC %ld M %ld\n", val,
260	       (val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT,
261	       val & MVPCONF0_PTC, (val & MVPCONF0_M) >> MVPCONF0_M_SHIFT);
262}
263
264/* Find some VPE program space  */
265static void *alloc_progmem(unsigned long len)
266{
267#ifdef CONFIG_MIPS_VPE_LOADER_TOM
268	/* this means you must tell linux to use less memory than you physically have */
269	return pfn_to_kaddr(max_pfn);
270#else
271	// simple grab some mem for now
272	return kmalloc(len, GFP_KERNEL);
273#endif
274}
275
276static void release_progmem(void *ptr)
277{
278#ifndef CONFIG_MIPS_VPE_LOADER_TOM
279	kfree(ptr);
280#endif
281}
282
283/* Update size with this section: return offset. */
284static long get_offset(unsigned long *size, Elf_Shdr * sechdr)
285{
286	long ret;
287
288	ret = ALIGN(*size, sechdr->sh_addralign ? : 1);
289	*size = ret + sechdr->sh_size;
290	return ret;
291}
292
293/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
294   might -- code, read-only data, read-write data, small data.  Tally
295   sizes, and place the offsets into sh_entsize fields: high bit means it
296   belongs in init. */
297static void layout_sections(struct module *mod, const Elf_Ehdr * hdr,
298			    Elf_Shdr * sechdrs, const char *secstrings)
299{
300	static unsigned long const masks[][2] = {
301		/* NOTE: all executable code must be the first section
302		 * in this array; otherwise modify the text_size
303		 * finder in the two loops below */
304		{SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL},
305		{SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL},
306		{SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL},
307		{ARCH_SHF_SMALL | SHF_ALLOC, 0}
308	};
309	unsigned int m, i;
310
311	for (i = 0; i < hdr->e_shnum; i++)
312		sechdrs[i].sh_entsize = ~0UL;
313
314	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
315		for (i = 0; i < hdr->e_shnum; ++i) {
316			Elf_Shdr *s = &sechdrs[i];
317
318			//  || strncmp(secstrings + s->sh_name, ".init", 5) == 0)
319			if ((s->sh_flags & masks[m][0]) != masks[m][0]
320			    || (s->sh_flags & masks[m][1])
321			    || s->sh_entsize != ~0UL)
322				continue;
323			s->sh_entsize = get_offset(&mod->core_size, s);
324		}
325
326		if (m == 0)
327			mod->core_text_size = mod->core_size;
328
329	}
330}
331
332
333/* from module-elf32.c, but subverted a little */
334
335struct mips_hi16 {
336	struct mips_hi16 *next;
337	Elf32_Addr *addr;
338	Elf32_Addr value;
339};
340
341static struct mips_hi16 *mips_hi16_list;
342static unsigned int gp_offs, gp_addr;
343
344static int apply_r_mips_none(struct module *me, uint32_t *location,
345			     Elf32_Addr v)
346{
347	return 0;
348}
349
350static int apply_r_mips_gprel16(struct module *me, uint32_t *location,
351				Elf32_Addr v)
352{
353	int rel;
354
355	if( !(*location & 0xffff) ) {
356		rel = (int)v - gp_addr;
357	}
358	else {
359		/* .sbss + gp(relative) + offset */
360		/* kludge! */
361		rel =  (int)(short)((int)v + gp_offs +
362				    (int)(short)(*location & 0xffff) - gp_addr);
363	}
364
365	if( (rel > 32768) || (rel < -32768) ) {
366		printk(KERN_DEBUG "VPE loader: apply_r_mips_gprel16: "
367		       "relative address 0x%x out of range of gp register\n",
368		       rel);
369		return -ENOEXEC;
370	}
371
372	*location = (*location & 0xffff0000) | (rel & 0xffff);
373
374	return 0;
375}
376
377static int apply_r_mips_pc16(struct module *me, uint32_t *location,
378			     Elf32_Addr v)
379{
380	int rel;
381	rel = (((unsigned int)v - (unsigned int)location));
382	rel >>= 2;		// because the offset is in _instructions_ not bytes.
383	rel -= 1;		// and one instruction less due to the branch delay slot.
384
385	if( (rel > 32768) || (rel < -32768) ) {
386		printk(KERN_DEBUG "VPE loader: "
387 		       "apply_r_mips_pc16: relative address out of range 0x%x\n", rel);
388		return -ENOEXEC;
389	}
390
391	*location = (*location & 0xffff0000) | (rel & 0xffff);
392
393	return 0;
394}
395
396static int apply_r_mips_32(struct module *me, uint32_t *location,
397			   Elf32_Addr v)
398{
399	*location += v;
400
401	return 0;
402}
403
404static int apply_r_mips_26(struct module *me, uint32_t *location,
405			   Elf32_Addr v)
406{
407	if (v % 4) {
408		printk(KERN_DEBUG "VPE loader: apply_r_mips_26 "
409		       " unaligned relocation\n");
410		return -ENOEXEC;
411	}
412
413/*
414 * Not desperately convinced this is a good check of an overflow condition
415 * anyway. But it gets in the way of handling undefined weak symbols which
416 * we want to set to zero.
417 * if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
418 * printk(KERN_ERR
419 * "module %s: relocation overflow\n",
420 * me->name);
421 * return -ENOEXEC;
422 * }
423 */
424
425	*location = (*location & ~0x03ffffff) |
426		((*location + (v >> 2)) & 0x03ffffff);
427	return 0;
428}
429
430static int apply_r_mips_hi16(struct module *me, uint32_t *location,
431			     Elf32_Addr v)
432{
433	struct mips_hi16 *n;
434
435	/*
436	 * We cannot relocate this one now because we don't know the value of
437	 * the carry we need to add.  Save the information, and let LO16 do the
438	 * actual relocation.
439	 */
440	n = kmalloc(sizeof *n, GFP_KERNEL);
441	if (!n)
442		return -ENOMEM;
443
444	n->addr = location;
445	n->value = v;
446	n->next = mips_hi16_list;
447	mips_hi16_list = n;
448
449	return 0;
450}
451
452static int apply_r_mips_lo16(struct module *me, uint32_t *location,
453			     Elf32_Addr v)
454{
455	unsigned long insnlo = *location;
456	Elf32_Addr val, vallo;
457
458	/* Sign extend the addend we extract from the lo insn.  */
459	vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
460
461	if (mips_hi16_list != NULL) {
462		struct mips_hi16 *l;
463
464		l = mips_hi16_list;
465		while (l != NULL) {
466			struct mips_hi16 *next;
467			unsigned long insn;
468
469			/*
470			 * The value for the HI16 had best be the same.
471			 */
472 			if (v != l->value) {
473				printk(KERN_DEBUG "VPE loader: "
474				       "apply_r_mips_lo16/hi16: 	"
475				       "inconsistent value information\n");
476				return -ENOEXEC;
477			}
478
479			/*
480			 * Do the HI16 relocation.  Note that we actually don't
481			 * need to know anything about the LO16 itself, except
482			 * where to find the low 16 bits of the addend needed
483			 * by the LO16.
484			 */
485			insn = *l->addr;
486			val = ((insn & 0xffff) << 16) + vallo;
487			val += v;
488
489			/*
490			 * Account for the sign extension that will happen in
491			 * the low bits.
492			 */
493			val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
494
495			insn = (insn & ~0xffff) | val;
496			*l->addr = insn;
497
498			next = l->next;
499			kfree(l);
500			l = next;
501		}
502
503		mips_hi16_list = NULL;
504	}
505
506	/*
507	 * Ok, we're done with the HI16 relocs.  Now deal with the LO16.
508	 */
509	val = v + vallo;
510	insnlo = (insnlo & ~0xffff) | (val & 0xffff);
511	*location = insnlo;
512
513	return 0;
514}
515
516static int (*reloc_handlers[]) (struct module *me, uint32_t *location,
517				Elf32_Addr v) = {
518	[R_MIPS_NONE]	= apply_r_mips_none,
519	[R_MIPS_32]	= apply_r_mips_32,
520	[R_MIPS_26]	= apply_r_mips_26,
521	[R_MIPS_HI16]	= apply_r_mips_hi16,
522	[R_MIPS_LO16]	= apply_r_mips_lo16,
523	[R_MIPS_GPREL16] = apply_r_mips_gprel16,
524	[R_MIPS_PC16] = apply_r_mips_pc16
525};
526
527static char *rstrs[] = {
528	[R_MIPS_NONE]	= "MIPS_NONE",
529	[R_MIPS_32]	= "MIPS_32",
530	[R_MIPS_26]	= "MIPS_26",
531	[R_MIPS_HI16]	= "MIPS_HI16",
532	[R_MIPS_LO16]	= "MIPS_LO16",
533	[R_MIPS_GPREL16] = "MIPS_GPREL16",
534	[R_MIPS_PC16] = "MIPS_PC16"
535};
536
537int apply_relocations(Elf32_Shdr *sechdrs,
538		      const char *strtab,
539		      unsigned int symindex,
540		      unsigned int relsec,
541		      struct module *me)
542{
543	Elf32_Rel *rel = (void *) sechdrs[relsec].sh_addr;
544	Elf32_Sym *sym;
545	uint32_t *location;
546	unsigned int i;
547	Elf32_Addr v;
548	int res;
549
550	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
551		Elf32_Word r_info = rel[i].r_info;
552
553		/* This is where to make the change */
554		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
555			+ rel[i].r_offset;
556		/* This is the symbol it is referring to */
557		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
558			+ ELF32_R_SYM(r_info);
559
560		if (!sym->st_value) {
561			printk(KERN_DEBUG "%s: undefined weak symbol %s\n",
562			       me->name, strtab + sym->st_name);
563			/* just print the warning, dont barf */
564		}
565
566		v = sym->st_value;
567
568		res = reloc_handlers[ELF32_R_TYPE(r_info)](me, location, v);
569		if( res ) {
570			char *r = rstrs[ELF32_R_TYPE(r_info)];
571		    	printk(KERN_WARNING "VPE loader: .text+0x%x "
572			       "relocation type %s for symbol \"%s\" failed\n",
573			       rel[i].r_offset, r ? r : "UNKNOWN",
574			       strtab + sym->st_name);
575			return res;
576		}
577	}
578
579	return 0;
580}
581
582void save_gp_address(unsigned int secbase, unsigned int rel)
583{
584	gp_addr = secbase + rel;
585	gp_offs = gp_addr - (secbase & 0xffff0000);
586}
587/* end module-elf32.c */
588
589
590
591/* Change all symbols so that sh_value encodes the pointer directly. */
592static void simplify_symbols(Elf_Shdr * sechdrs,
593			    unsigned int symindex,
594			    const char *strtab,
595			    const char *secstrings,
596			    unsigned int nsecs, struct module *mod)
597{
598	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
599	unsigned long secbase, bssbase = 0;
600	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
601	int size;
602
603	/* find the .bss section for COMMON symbols */
604	for (i = 0; i < nsecs; i++) {
605		if (strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) == 0) {
606			bssbase = sechdrs[i].sh_addr;
607			break;
608		}
609	}
610
611	for (i = 1; i < n; i++) {
612		switch (sym[i].st_shndx) {
613		case SHN_COMMON:
614			/* Allocate space for the symbol in the .bss section.
615			   st_value is currently size.
616			   We want it to have the address of the symbol. */
617
618			size = sym[i].st_value;
619			sym[i].st_value = bssbase;
620
621			bssbase += size;
622			break;
623
624		case SHN_ABS:
625			/* Don't need to do anything */
626			break;
627
628		case SHN_UNDEF:
629			/* ret = -ENOENT; */
630			break;
631
632		case SHN_MIPS_SCOMMON:
633			printk(KERN_DEBUG "simplify_symbols: ignoring SHN_MIPS_SCOMMON"
634			       "symbol <%s> st_shndx %d\n", strtab + sym[i].st_name,
635			       sym[i].st_shndx);
636			// .sbss section
637			break;
638
639		default:
640			secbase = sechdrs[sym[i].st_shndx].sh_addr;
641
642			if (strncmp(strtab + sym[i].st_name, "_gp", 3) == 0) {
643				save_gp_address(secbase, sym[i].st_value);
644			}
645
646			sym[i].st_value += secbase;
647			break;
648		}
649	}
650}
651
652#ifdef DEBUG_ELFLOADER
653static void dump_elfsymbols(Elf_Shdr * sechdrs, unsigned int symindex,
654			    const char *strtab, struct module *mod)
655{
656	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
657	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
658
659	printk(KERN_DEBUG "dump_elfsymbols: n %d\n", n);
660	for (i = 1; i < n; i++) {
661		printk(KERN_DEBUG " i %d name <%s> 0x%x\n", i,
662		       strtab + sym[i].st_name, sym[i].st_value);
663	}
664}
665#endif
666
667static void dump_tc(struct tc *t)
668{
669  	unsigned long val;
670
671  	settc(t->index);
672 	printk(KERN_DEBUG "VPE loader: TC index %d targtc %ld "
673 	       "TCStatus 0x%lx halt 0x%lx\n",
674  	       t->index, read_c0_vpecontrol() & VPECONTROL_TARGTC,
675  	       read_tc_c0_tcstatus(), read_tc_c0_tchalt());
676
677 	printk(KERN_DEBUG " tcrestart 0x%lx\n", read_tc_c0_tcrestart());
678 	printk(KERN_DEBUG " tcbind 0x%lx\n", read_tc_c0_tcbind());
679
680  	val = read_c0_vpeconf0();
681 	printk(KERN_DEBUG " VPEConf0 0x%lx MVP %ld\n", val,
682  	       (val & VPECONF0_MVP) >> VPECONF0_MVP_SHIFT);
683
684 	printk(KERN_DEBUG " c0 status 0x%lx\n", read_vpe_c0_status());
685 	printk(KERN_DEBUG " c0 cause 0x%lx\n", read_vpe_c0_cause());
686
687 	printk(KERN_DEBUG " c0 badvaddr 0x%lx\n", read_vpe_c0_badvaddr());
688 	printk(KERN_DEBUG " c0 epc 0x%lx\n", read_vpe_c0_epc());
689}
690
691static void dump_tclist(void)
692{
693	struct tc *t;
694
695	list_for_each_entry(t, &vpecontrol.tc_list, list) {
696		dump_tc(t);
697	}
698}
699
700/* We are prepared so configure and start the VPE... */
701static int vpe_run(struct vpe * v)
702{
703	struct vpe_notifications *n;
704	unsigned long val, dmt_flag;
705	struct tc *t;
706
707	/* check we are the Master VPE */
708	val = read_c0_vpeconf0();
709	if (!(val & VPECONF0_MVP)) {
710		printk(KERN_WARNING
711		       "VPE loader: only Master VPE's are allowed to configure MT\n");
712		return -1;
713	}
714
715	/* disable MT (using dvpe) */
716	dvpe();
717
718	if (!list_empty(&v->tc)) {
719		if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
720			printk(KERN_WARNING "VPE loader: TC %d is already in use.\n",
721			       t->index);
722			return -ENOEXEC;
723		}
724	} else {
725		printk(KERN_WARNING "VPE loader: No TC's associated with VPE %d\n",
726		       v->minor);
727		return -ENOEXEC;
728	}
729
730	/* Put MVPE's into 'configuration state' */
731	set_c0_mvpcontrol(MVPCONTROL_VPC);
732
733	settc(t->index);
734
735	/* should check it is halted, and not activated */
736	if ((read_tc_c0_tcstatus() & TCSTATUS_A) || !(read_tc_c0_tchalt() & TCHALT_H)) {
737		printk(KERN_WARNING "VPE loader: TC %d is already doing something!\n",
738		       t->index);
739		dump_tclist();
740		return -ENOEXEC;
741	}
742
743	/*
744	 * Disable multi-threaded execution whilst we activate, clear the
745	 * halt bit and bound the tc to the other VPE...
746	 */
747	dmt_flag = dmt();
748
749	/* Write the address we want it to start running from in the TCPC register. */
750	write_tc_c0_tcrestart((unsigned long)v->__start);
751	write_tc_c0_tccontext((unsigned long)0);
752	/*
753	 * Mark the TC as activated, not interrupt exempt and not dynamically
754	 * allocatable
755	 */
756	val = read_tc_c0_tcstatus();
757	val = (val & ~(TCSTATUS_DA | TCSTATUS_IXMT)) | TCSTATUS_A;
758	write_tc_c0_tcstatus(val);
759
760	write_tc_c0_tchalt(read_tc_c0_tchalt() & ~TCHALT_H);
761
762	/*
763	 * The sde-kit passes 'memsize' to __start in $a3, so set something
764	 * here...  Or set $a3 to zero and define DFLT_STACK_SIZE and
765	 * DFLT_HEAP_SIZE when you compile your program
766	 */
767 	mttgpr(7, physical_memsize);
768
769
770	/* set up VPE1 */
771	/*
772	 * bind the TC to VPE 1 as late as possible so we only have the final
773	 * VPE registers to set up, and so an EJTAG probe can trigger on it
774	 */
775 	write_tc_c0_tcbind((read_tc_c0_tcbind() & ~TCBIND_CURVPE) | v->minor);
776
777	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~(VPECONF0_VPA));
778
779	back_to_back_c0_hazard();
780
781	/* Set up the XTC bit in vpeconf0 to point at our tc */
782	write_vpe_c0_vpeconf0( (read_vpe_c0_vpeconf0() & ~(VPECONF0_XTC))
783	                      | (t->index << VPECONF0_XTC_SHIFT));
784
785	back_to_back_c0_hazard();
786
787	/* enable this VPE */
788	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA);
789
790	/* clear out any left overs from a previous program */
791	write_vpe_c0_status(0);
792	write_vpe_c0_cause(0);
793
794	/* take system out of configuration state */
795	clear_c0_mvpcontrol(MVPCONTROL_VPC);
796
797	/* now safe to re-enable multi-threading */
798	emt(dmt_flag);
799
800	/* set it running */
801	evpe(EVPE_ENABLE);
802
803	list_for_each_entry(n, &v->notify, list) {
804		n->start(v->minor);
805	}
806
807	return 0;
808}
809
810static int find_vpe_symbols(struct vpe * v, Elf_Shdr * sechdrs,
811				      unsigned int symindex, const char *strtab,
812				      struct module *mod)
813{
814	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
815	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
816
817	for (i = 1; i < n; i++) {
818		if (strcmp(strtab + sym[i].st_name, "__start") == 0) {
819			v->__start = sym[i].st_value;
820		}
821
822		if (strcmp(strtab + sym[i].st_name, "vpe_shared") == 0) {
823			v->shared_ptr = (void *)sym[i].st_value;
824		}
825	}
826
827	if ( (v->__start == 0) || (v->shared_ptr == NULL))
828		return -1;
829
830	return 0;
831}
832
833/*
834 * Allocates a VPE with some program code space(the load address), copies the
835 * contents of the program (p)buffer performing relocatations/etc, free's it
836 * when finished.
837 */
838static int vpe_elfload(struct vpe * v)
839{
840	Elf_Ehdr *hdr;
841	Elf_Shdr *sechdrs;
842	long err = 0;
843	char *secstrings, *strtab = NULL;
844	unsigned int len, i, symindex = 0, strindex = 0, relocate = 0;
845	struct module mod;	// so we can re-use the relocations code
846
847	memset(&mod, 0, sizeof(struct module));
848	strcpy(mod.name, "VPE loader");
849
850	hdr = (Elf_Ehdr *) v->pbuffer;
851	len = v->plen;
852
853	/* Sanity checks against insmoding binaries or wrong arch,
854	   weird elf version */
855	if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
856	    || (hdr->e_type != ET_REL && hdr->e_type != ET_EXEC)
857	    || !elf_check_arch(hdr)
858	    || hdr->e_shentsize != sizeof(*sechdrs)) {
859		printk(KERN_WARNING
860		       "VPE loader: program wrong arch or weird elf version\n");
861
862		return -ENOEXEC;
863	}
864
865	if (hdr->e_type == ET_REL)
866		relocate = 1;
867
868	if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
869		printk(KERN_ERR "VPE loader: program length %u truncated\n",
870		       len);
871
872		return -ENOEXEC;
873	}
874
875	/* Convenience variables */
876	sechdrs = (void *)hdr + hdr->e_shoff;
877	secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
878	sechdrs[0].sh_addr = 0;
879
880	/* And these should exist, but gcc whinges if we don't init them */
881	symindex = strindex = 0;
882
883	if (relocate) {
884		for (i = 1; i < hdr->e_shnum; i++) {
885			if (sechdrs[i].sh_type != SHT_NOBITS
886			    && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) {
887				printk(KERN_ERR "VPE program length %u truncated\n",
888				       len);
889				return -ENOEXEC;
890			}
891
892			/* Mark all sections sh_addr with their address in the
893			   temporary image. */
894			sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
895
896			/* Internal symbols and strings. */
897			if (sechdrs[i].sh_type == SHT_SYMTAB) {
898				symindex = i;
899				strindex = sechdrs[i].sh_link;
900				strtab = (char *)hdr + sechdrs[strindex].sh_offset;
901			}
902		}
903		layout_sections(&mod, hdr, sechdrs, secstrings);
904	}
905
906	v->load_addr = alloc_progmem(mod.core_size);
907	memset(v->load_addr, 0, mod.core_size);
908
909	printk("VPE loader: loading to %p\n", v->load_addr);
910
911	if (relocate) {
912		for (i = 0; i < hdr->e_shnum; i++) {
913			void *dest;
914
915			if (!(sechdrs[i].sh_flags & SHF_ALLOC))
916				continue;
917
918			dest = v->load_addr + sechdrs[i].sh_entsize;
919
920			if (sechdrs[i].sh_type != SHT_NOBITS)
921				memcpy(dest, (void *)sechdrs[i].sh_addr,
922				       sechdrs[i].sh_size);
923			/* Update sh_addr to point to copy in image. */
924			sechdrs[i].sh_addr = (unsigned long)dest;
925
926			printk(KERN_DEBUG " section sh_name %s sh_addr 0x%x\n",
927			       secstrings + sechdrs[i].sh_name, sechdrs[i].sh_addr);
928		}
929
930 		/* Fix up syms, so that st_value is a pointer to location. */
931 		simplify_symbols(sechdrs, symindex, strtab, secstrings,
932 				 hdr->e_shnum, &mod);
933
934 		/* Now do relocations. */
935 		for (i = 1; i < hdr->e_shnum; i++) {
936 			const char *strtab = (char *)sechdrs[strindex].sh_addr;
937 			unsigned int info = sechdrs[i].sh_info;
938
939 			/* Not a valid relocation section? */
940 			if (info >= hdr->e_shnum)
941 				continue;
942
943 			/* Don't bother with non-allocated sections */
944 			if (!(sechdrs[info].sh_flags & SHF_ALLOC))
945 				continue;
946
947 			if (sechdrs[i].sh_type == SHT_REL)
948 				err = apply_relocations(sechdrs, strtab, symindex, i,
949 							&mod);
950 			else if (sechdrs[i].sh_type == SHT_RELA)
951 				err = apply_relocate_add(sechdrs, strtab, symindex, i,
952 							 &mod);
953 			if (err < 0)
954 				return err;
955
956  		}
957  	} else {
958  		for (i = 0; i < hdr->e_shnum; i++) {
959
960 			/* Internal symbols and strings. */
961 			if (sechdrs[i].sh_type == SHT_SYMTAB) {
962 				symindex = i;
963 				strindex = sechdrs[i].sh_link;
964 				strtab = (char *)hdr + sechdrs[strindex].sh_offset;
965
966 				/* mark the symtab's address for when we try to find the
967 				   magic symbols */
968 				sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
969 			}
970
971 			/* filter sections we dont want in the final image */
972 			if (!(sechdrs[i].sh_flags & SHF_ALLOC) ||
973 			    (sechdrs[i].sh_type == SHT_MIPS_REGINFO)) {
974 				printk( KERN_DEBUG " ignoring section, "
975 					"name %s type %x address 0x%x \n",
976 					secstrings + sechdrs[i].sh_name,
977 					sechdrs[i].sh_type, sechdrs[i].sh_addr);
978 				continue;
979 			}
980
981  			if (sechdrs[i].sh_addr < (unsigned int)v->load_addr) {
982 				printk( KERN_WARNING "VPE loader: "
983 					"fully linked image has invalid section, "
984 					"name %s type %x address 0x%x, before load "
985 					"address of 0x%x\n",
986 					secstrings + sechdrs[i].sh_name,
987 					sechdrs[i].sh_type, sechdrs[i].sh_addr,
988 					(unsigned int)v->load_addr);
989  				return -ENOEXEC;
990  			}
991
992 			printk(KERN_DEBUG " copying section sh_name %s, sh_addr 0x%x "
993			       "size 0x%x0 from x%p\n",
994			       secstrings + sechdrs[i].sh_name, sechdrs[i].sh_addr,
995			       sechdrs[i].sh_size, hdr + sechdrs[i].sh_offset);
996
997  			if (sechdrs[i].sh_type != SHT_NOBITS)
998				memcpy((void *)sechdrs[i].sh_addr,
999				       (char *)hdr + sechdrs[i].sh_offset,
1000 				       sechdrs[i].sh_size);
1001			else
1002				memset((void *)sechdrs[i].sh_addr, 0, sechdrs[i].sh_size);
1003		}
1004	}
1005
1006	/* make sure it's physically written out */
1007	flush_icache_range((unsigned long)v->load_addr,
1008			   (unsigned long)v->load_addr + v->len);
1009
1010	if ((find_vpe_symbols(v, sechdrs, symindex, strtab, &mod)) < 0) {
1011		if (v->__start == 0) {
1012			printk(KERN_WARNING "VPE loader: program does not contain "
1013			       "a __start symbol\n");
1014			return -ENOEXEC;
1015		}
1016
1017		if (v->shared_ptr == NULL)
1018			printk(KERN_WARNING "VPE loader: "
1019			       "program does not contain vpe_shared symbol.\n"
1020			       " Unable to use AMVP (AP/SP) facilities.\n");
1021	}
1022
1023	printk(" elf loaded\n");
1024	return 0;
1025}
1026
1027__attribute_used__ void dump_vpe(struct vpe * v)
1028{
1029	struct tc *t;
1030
1031	settc(v->minor);
1032
1033	printk(KERN_DEBUG "VPEControl 0x%lx\n", read_vpe_c0_vpecontrol());
1034	printk(KERN_DEBUG "VPEConf0 0x%lx\n", read_vpe_c0_vpeconf0());
1035
1036	list_for_each_entry(t, &vpecontrol.tc_list, list)
1037		dump_tc(t);
1038}
1039
1040static void cleanup_tc(struct tc *tc)
1041{
1042	int tmp;
1043
1044	/* Put MVPE's into 'configuration state' */
1045	set_c0_mvpcontrol(MVPCONTROL_VPC);
1046
1047	settc(tc->index);
1048	tmp = read_tc_c0_tcstatus();
1049
1050	/* mark not allocated and not dynamically allocatable */
1051	tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1052	tmp |= TCSTATUS_IXMT;	/* interrupt exempt */
1053	write_tc_c0_tcstatus(tmp);
1054
1055	write_tc_c0_tchalt(TCHALT_H);
1056
1057	/* bind it to anything other than VPE1 */
1058	write_tc_c0_tcbind(read_tc_c0_tcbind() & ~TCBIND_CURVPE); // | TCBIND_CURVPE
1059
1060	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1061}
1062
1063static int getcwd(char *buff, int size)
1064{
1065	mm_segment_t old_fs;
1066	int ret;
1067
1068	old_fs = get_fs();
1069	set_fs(KERNEL_DS);
1070
1071	ret = sys_getcwd(buff,size);
1072
1073	set_fs(old_fs);
1074
1075	return ret;
1076}
1077
1078/* checks VPE is unused and gets ready to load program  */
1079static int vpe_open(struct inode *inode, struct file *filp)
1080{
1081	int minor, ret;
1082	enum vpe_state state;
1083	struct vpe *v;
1084	struct vpe_notifications *not;
1085
1086	/* assume only 1 device at the mo. */
1087	if ((minor = iminor(inode)) != 1) {
1088		printk(KERN_WARNING "VPE loader: only vpe1 is supported\n");
1089		return -ENODEV;
1090	}
1091
1092	if ((v = get_vpe(minor)) == NULL) {
1093		printk(KERN_WARNING "VPE loader: unable to get vpe\n");
1094		return -ENODEV;
1095	}
1096
1097	state = xchg(&v->state, VPE_STATE_INUSE);
1098	if (state != VPE_STATE_UNUSED) {
1099		dvpe();
1100
1101		printk(KERN_DEBUG "VPE loader: tc in use dumping regs\n");
1102
1103		dump_tc(get_tc(minor));
1104
1105		list_for_each_entry(not, &v->notify, list) {
1106			not->stop(minor);
1107		}
1108
1109		release_progmem(v->load_addr);
1110		cleanup_tc(get_tc(minor));
1111	}
1112
1113	/* this of-course trashes what was there before... */
1114	v->pbuffer = vmalloc(P_SIZE);
1115	v->plen = P_SIZE;
1116	v->load_addr = NULL;
1117	v->len = 0;
1118
1119	v->uid = filp->f_uid;
1120	v->gid = filp->f_gid;
1121
1122#ifdef CONFIG_MIPS_APSP_KSPD
1123	/* get kspd to tell us when a syscall_exit happens */
1124	if (!kspd_events_reqd) {
1125		kspd_notify(&kspd_events);
1126		kspd_events_reqd++;
1127	}
1128#endif
1129
1130	v->cwd[0] = 0;
1131	ret = getcwd(v->cwd, VPE_PATH_MAX);
1132	if (ret < 0)
1133		printk(KERN_WARNING "VPE loader: open, getcwd returned %d\n", ret);
1134
1135	v->shared_ptr = NULL;
1136	v->__start = 0;
1137	return 0;
1138}
1139
1140static int vpe_release(struct inode *inode, struct file *filp)
1141{
1142	int minor, ret = 0;
1143	struct vpe *v;
1144	Elf_Ehdr *hdr;
1145
1146	minor = iminor(inode);
1147	if ((v = get_vpe(minor)) == NULL)
1148		return -ENODEV;
1149
1150	// simple case of fire and forget, so tell the VPE to run...
1151
1152	hdr = (Elf_Ehdr *) v->pbuffer;
1153	if (memcmp(hdr->e_ident, ELFMAG, 4) == 0) {
1154		if (vpe_elfload(v) >= 0)
1155			vpe_run(v);
1156		else {
1157 			printk(KERN_WARNING "VPE loader: ELF load failed.\n");
1158			ret = -ENOEXEC;
1159		}
1160	} else {
1161 		printk(KERN_WARNING "VPE loader: only elf files are supported\n");
1162		ret = -ENOEXEC;
1163	}
1164
1165	/* It's good to be able to run the SP and if it chokes have a look at
1166	   the /dev/rt?. But if we reset the pointer to the shared struct we
1167	   loose what has happened. So perhaps if garbage is sent to the vpe
1168	   device, use it as a trigger for the reset. Hopefully a nice
1169	   executable will be along shortly. */
1170	if (ret < 0)
1171		v->shared_ptr = NULL;
1172
1173	// cleanup any temp buffers
1174	if (v->pbuffer)
1175		vfree(v->pbuffer);
1176	v->plen = 0;
1177	return ret;
1178}
1179
1180static ssize_t vpe_write(struct file *file, const char __user * buffer,
1181			 size_t count, loff_t * ppos)
1182{
1183	int minor;
1184	size_t ret = count;
1185	struct vpe *v;
1186
1187	minor = iminor(file->f_path.dentry->d_inode);
1188	if ((v = get_vpe(minor)) == NULL)
1189		return -ENODEV;
1190
1191	if (v->pbuffer == NULL) {
1192		printk(KERN_ERR "VPE loader: no buffer for program\n");
1193		return -ENOMEM;
1194	}
1195
1196	if ((count + v->len) > v->plen) {
1197		printk(KERN_WARNING
1198		       "VPE loader: elf size too big. Perhaps strip uneeded symbols\n");
1199		return -ENOMEM;
1200	}
1201
1202	count -= copy_from_user(v->pbuffer + v->len, buffer, count);
1203	if (!count)
1204		return -EFAULT;
1205
1206	v->len += count;
1207	return ret;
1208}
1209
1210static const struct file_operations vpe_fops = {
1211	.owner = THIS_MODULE,
1212	.open = vpe_open,
1213	.release = vpe_release,
1214	.write = vpe_write
1215};
1216
1217/* module wrapper entry points */
1218/* give me a vpe */
1219vpe_handle vpe_alloc(void)
1220{
1221	int i;
1222	struct vpe *v;
1223
1224	/* find a vpe */
1225	for (i = 1; i < MAX_VPES; i++) {
1226		if ((v = get_vpe(i)) != NULL) {
1227			v->state = VPE_STATE_INUSE;
1228			return v;
1229		}
1230	}
1231	return NULL;
1232}
1233
1234EXPORT_SYMBOL(vpe_alloc);
1235
1236/* start running from here */
1237int vpe_start(vpe_handle vpe, unsigned long start)
1238{
1239	struct vpe *v = vpe;
1240
1241	v->__start = start;
1242	return vpe_run(v);
1243}
1244
1245EXPORT_SYMBOL(vpe_start);
1246
1247/* halt it for now */
1248int vpe_stop(vpe_handle vpe)
1249{
1250	struct vpe *v = vpe;
1251	struct tc *t;
1252	unsigned int evpe_flags;
1253
1254	evpe_flags = dvpe();
1255
1256	if ((t = list_entry(v->tc.next, struct tc, tc)) != NULL) {
1257
1258		settc(t->index);
1259		write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1260	}
1261
1262	evpe(evpe_flags);
1263
1264	return 0;
1265}
1266
1267EXPORT_SYMBOL(vpe_stop);
1268
1269/* I've done with it thank you */
1270int vpe_free(vpe_handle vpe)
1271{
1272	struct vpe *v = vpe;
1273	struct tc *t;
1274	unsigned int evpe_flags;
1275
1276	if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
1277		return -ENOEXEC;
1278	}
1279
1280	evpe_flags = dvpe();
1281
1282	/* Put MVPE's into 'configuration state' */
1283	set_c0_mvpcontrol(MVPCONTROL_VPC);
1284
1285	settc(t->index);
1286	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1287
1288	/* mark the TC unallocated and halt'ed */
1289	write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A);
1290	write_tc_c0_tchalt(TCHALT_H);
1291
1292	v->state = VPE_STATE_UNUSED;
1293
1294	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1295	evpe(evpe_flags);
1296
1297	return 0;
1298}
1299
1300EXPORT_SYMBOL(vpe_free);
1301
1302void *vpe_get_shared(int index)
1303{
1304	struct vpe *v;
1305
1306	if ((v = get_vpe(index)) == NULL)
1307		return NULL;
1308
1309	return v->shared_ptr;
1310}
1311
1312EXPORT_SYMBOL(vpe_get_shared);
1313
1314int vpe_getuid(int index)
1315{
1316	struct vpe *v;
1317
1318	if ((v = get_vpe(index)) == NULL)
1319		return -1;
1320
1321	return v->uid;
1322}
1323
1324EXPORT_SYMBOL(vpe_getuid);
1325
1326int vpe_getgid(int index)
1327{
1328	struct vpe *v;
1329
1330	if ((v = get_vpe(index)) == NULL)
1331		return -1;
1332
1333	return v->gid;
1334}
1335
1336EXPORT_SYMBOL(vpe_getgid);
1337
1338int vpe_notify(int index, struct vpe_notifications *notify)
1339{
1340	struct vpe *v;
1341
1342	if ((v = get_vpe(index)) == NULL)
1343		return -1;
1344
1345	list_add(&notify->list, &v->notify);
1346	return 0;
1347}
1348
1349EXPORT_SYMBOL(vpe_notify);
1350
1351char *vpe_getcwd(int index)
1352{
1353	struct vpe *v;
1354
1355	if ((v = get_vpe(index)) == NULL)
1356		return NULL;
1357
1358	return v->cwd;
1359}
1360
1361EXPORT_SYMBOL(vpe_getcwd);
1362
1363#ifdef CONFIG_MIPS_APSP_KSPD
1364static void kspd_sp_exit( int sp_id)
1365{
1366	cleanup_tc(get_tc(sp_id));
1367}
1368#endif
1369
1370static struct device *vpe_dev;
1371
1372static int __init vpe_module_init(void)
1373{
1374	struct vpe *v = NULL;
1375	struct device *dev;
1376	struct tc *t;
1377	unsigned long val;
1378	int i, err;
1379
1380	if (!cpu_has_mipsmt) {
1381		printk("VPE loader: not a MIPS MT capable processor\n");
1382		return -ENODEV;
1383	}
1384
1385	major = register_chrdev(0, module_name, &vpe_fops);
1386	if (major < 0) {
1387		printk("VPE loader: unable to register character device\n");
1388		return major;
1389	}
1390
1391	dev = device_create(mt_class, NULL, MKDEV(major, minor),
1392	                    "tc%d", minor);
1393	if (IS_ERR(dev)) {
1394		err = PTR_ERR(dev);
1395		goto out_chrdev;
1396	}
1397	vpe_dev = dev;
1398
1399	dmt();
1400	dvpe();
1401
1402	/* Put MVPE's into 'configuration state' */
1403	set_c0_mvpcontrol(MVPCONTROL_VPC);
1404
1405	/* dump_mtregs(); */
1406
1407
1408	val = read_c0_mvpconf0();
1409	for (i = 0; i < ((val & MVPCONF0_PTC) + 1); i++) {
1410		t = alloc_tc(i);
1411
1412		/* VPE's */
1413		if (i < ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1) {
1414			settc(i);
1415
1416			if ((v = alloc_vpe(i)) == NULL) {
1417				printk(KERN_WARNING "VPE: unable to allocate VPE\n");
1418				return -ENODEV;
1419			}
1420
1421			/* add the tc to the list of this vpe's tc's. */
1422			list_add(&t->tc, &v->tc);
1423
1424			/* deactivate all but vpe0 */
1425			if (i != 0) {
1426				unsigned long tmp = read_vpe_c0_vpeconf0();
1427
1428				tmp &= ~VPECONF0_VPA;
1429
1430				/* master VPE */
1431				tmp |= VPECONF0_MVP;
1432				write_vpe_c0_vpeconf0(tmp);
1433			}
1434
1435			/* disable multi-threading with TC's */
1436			write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE);
1437
1438			if (i != 0) {
1439				/*
1440				 * Set config to be the same as vpe0,
1441				 * particularly kseg0 coherency alg
1442				 */
1443				write_vpe_c0_config(read_c0_config());
1444			}
1445		}
1446
1447		/* TC's */
1448		t->pvpe = v;	/* set the parent vpe */
1449
1450		if (i != 0) {
1451			unsigned long tmp;
1452
1453			settc(i);
1454
1455			/* Any TC that is bound to VPE0 gets left as is - in case
1456			   we are running SMTC on VPE0. A TC that is bound to any
1457			   other VPE gets bound to VPE0, ideally I'd like to make
1458			   it homeless but it doesn't appear to let me bind a TC
1459			   to a non-existent VPE. Which is perfectly reasonable.
1460
1461			   The (un)bound state is visible to an EJTAG probe so may
1462			   notify GDB...
1463			*/
1464
1465			if (((tmp = read_tc_c0_tcbind()) & TCBIND_CURVPE)) {
1466				/* tc is bound >vpe0 */
1467				write_tc_c0_tcbind(tmp & ~TCBIND_CURVPE);
1468
1469				t->pvpe = get_vpe(0);	/* set the parent vpe */
1470			}
1471
1472			tmp = read_tc_c0_tcstatus();
1473
1474			/* mark not activated and not dynamically allocatable */
1475			tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1476			tmp |= TCSTATUS_IXMT;	/* interrupt exempt */
1477			write_tc_c0_tcstatus(tmp);
1478
1479			write_tc_c0_tchalt(TCHALT_H);
1480		}
1481	}
1482
1483	/* release config state */
1484	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1485
1486#ifdef CONFIG_MIPS_APSP_KSPD
1487	kspd_events.kspd_sp_exit = kspd_sp_exit;
1488#endif
1489	return 0;
1490
1491out_chrdev:
1492	unregister_chrdev(major, module_name);
1493
1494	return err;
1495}
1496
1497static void __exit vpe_module_exit(void)
1498{
1499	struct vpe *v, *n;
1500
1501	list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list) {
1502		if (v->state != VPE_STATE_UNUSED) {
1503			release_vpe(v);
1504		}
1505	}
1506
1507	device_destroy(mt_class, MKDEV(major, minor));
1508	unregister_chrdev(major, module_name);
1509}
1510
1511module_init(vpe_module_init);
1512module_exit(vpe_module_exit);
1513MODULE_DESCRIPTION("MIPS VPE Loader");
1514MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
1515MODULE_LICENSE("GPL");
1516