xref: /openbmc/linux/arch/mips/kernel/vpe.c (revision 22246614)
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 #include <linux/kernel.h>
31 #include <linux/device.h>
32 #include <linux/module.h>
33 #include <linux/fs.h>
34 #include <linux/init.h>
35 #include <asm/uaccess.h>
36 #include <linux/slab.h>
37 #include <linux/list.h>
38 #include <linux/vmalloc.h>
39 #include <linux/elf.h>
40 #include <linux/seq_file.h>
41 #include <linux/syscalls.h>
42 #include <linux/moduleloader.h>
43 #include <linux/interrupt.h>
44 #include <linux/poll.h>
45 #include <linux/bootmem.h>
46 #include <asm/mipsregs.h>
47 #include <asm/mipsmtregs.h>
48 #include <asm/cacheflush.h>
49 #include <asm/atomic.h>
50 #include <asm/cpu.h>
51 #include <asm/mips_mt.h>
52 #include <asm/processor.h>
53 #include <asm/system.h>
54 #include <asm/vpe.h>
55 #include <asm/kspd.h>
56 
57 typedef void *vpe_handle;
58 
59 #ifndef ARCH_SHF_SMALL
60 #define ARCH_SHF_SMALL 0
61 #endif
62 
63 /* If this is set, the section belongs in the init part of the module */
64 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
65 
66 /*
67  * The number of TCs and VPEs physically available on the core
68  */
69 static int hw_tcs, hw_vpes;
70 static char module_name[] = "vpe";
71 static int major;
72 static const int minor = 1;	/* fixed for now  */
73 
74 #ifdef CONFIG_MIPS_APSP_KSPD
75  static struct kspd_notifications kspd_events;
76 static int kspd_events_reqd = 0;
77 #endif
78 
79 /* grab the likely amount of memory we will need. */
80 #ifdef CONFIG_MIPS_VPE_LOADER_TOM
81 #define P_SIZE (2 * 1024 * 1024)
82 #else
83 /* add an overhead to the max kmalloc size for non-striped symbols/etc */
84 #define P_SIZE (256 * 1024)
85 #endif
86 
87 extern unsigned long physical_memsize;
88 
89 #define MAX_VPES 16
90 #define VPE_PATH_MAX 256
91 
92 enum vpe_state {
93 	VPE_STATE_UNUSED = 0,
94 	VPE_STATE_INUSE,
95 	VPE_STATE_RUNNING
96 };
97 
98 enum tc_state {
99 	TC_STATE_UNUSED = 0,
100 	TC_STATE_INUSE,
101 	TC_STATE_RUNNING,
102 	TC_STATE_DYNAMIC
103 };
104 
105 struct vpe {
106 	enum vpe_state state;
107 
108 	/* (device) minor associated with this vpe */
109 	int minor;
110 
111 	/* elfloader stuff */
112 	void *load_addr;
113 	unsigned long len;
114 	char *pbuffer;
115 	unsigned long plen;
116 	unsigned int uid, gid;
117 	char cwd[VPE_PATH_MAX];
118 
119 	unsigned long __start;
120 
121 	/* tc's associated with this vpe */
122 	struct list_head tc;
123 
124 	/* The list of vpe's */
125 	struct list_head list;
126 
127 	/* shared symbol address */
128 	void *shared_ptr;
129 
130 	/* the list of who wants to know when something major happens */
131 	struct list_head notify;
132 
133 	unsigned int ntcs;
134 };
135 
136 struct tc {
137 	enum tc_state state;
138 	int index;
139 
140 	struct vpe *pvpe;	/* parent VPE */
141 	struct list_head tc;	/* The list of TC's with this VPE */
142 	struct list_head list;	/* The global list of tc's */
143 };
144 
145 struct {
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 
156 static void release_progmem(void *ptr);
157 extern void save_gp_address(unsigned int secbase, unsigned int rel);
158 
159 /* get the vpe associated with this minor */
160 struct vpe *get_vpe(int minor)
161 {
162 	struct vpe *v;
163 
164 	if (!cpu_has_mipsmt)
165 		return NULL;
166 
167 	list_for_each_entry(v, &vpecontrol.vpe_list, list) {
168 		if (v->minor == minor)
169 			return v;
170 	}
171 
172 	return NULL;
173 }
174 
175 /* get the vpe associated with this minor */
176 struct tc *get_tc(int index)
177 {
178 	struct tc *t;
179 
180 	list_for_each_entry(t, &vpecontrol.tc_list, list) {
181 		if (t->index == index)
182 			return t;
183 	}
184 
185 	return NULL;
186 }
187 
188 struct tc *get_tc_unused(void)
189 {
190 	struct tc *t;
191 
192 	list_for_each_entry(t, &vpecontrol.tc_list, list) {
193 		if (t->state == TC_STATE_UNUSED)
194 			return t;
195 	}
196 
197 	return NULL;
198 }
199 
200 /* allocate a vpe and associate it with this minor (or index) */
201 struct vpe *alloc_vpe(int minor)
202 {
203 	struct vpe *v;
204 
205 	if ((v = kzalloc(sizeof(struct vpe), GFP_KERNEL)) == NULL) {
206 		return NULL;
207 	}
208 
209 	INIT_LIST_HEAD(&v->tc);
210 	list_add_tail(&v->list, &vpecontrol.vpe_list);
211 
212 	INIT_LIST_HEAD(&v->notify);
213 	v->minor = minor;
214 	return v;
215 }
216 
217 /* allocate a tc. At startup only tc0 is running, all other can be halted. */
218 struct tc *alloc_tc(int index)
219 {
220 	struct tc *tc;
221 
222 	if ((tc = kzalloc(sizeof(struct tc), GFP_KERNEL)) == NULL)
223 		goto out;
224 
225 	INIT_LIST_HEAD(&tc->tc);
226 	tc->index = index;
227 	list_add_tail(&tc->list, &vpecontrol.tc_list);
228 
229 out:
230 	return tc;
231 }
232 
233 /* clean up and free everything */
234 void release_vpe(struct vpe *v)
235 {
236 	list_del(&v->list);
237 	if (v->load_addr)
238 		release_progmem(v);
239 	kfree(v);
240 }
241 
242 void dump_mtregs(void)
243 {
244 	unsigned long val;
245 
246 	val = read_c0_config3();
247 	printk("config3 0x%lx MT %ld\n", val,
248 	       (val & CONFIG3_MT) >> CONFIG3_MT_SHIFT);
249 
250 	val = read_c0_mvpcontrol();
251 	printk("MVPControl 0x%lx, STLB %ld VPC %ld EVP %ld\n", val,
252 	       (val & MVPCONTROL_STLB) >> MVPCONTROL_STLB_SHIFT,
253 	       (val & MVPCONTROL_VPC) >> MVPCONTROL_VPC_SHIFT,
254 	       (val & MVPCONTROL_EVP));
255 
256 	val = read_c0_mvpconf0();
257 	printk("mvpconf0 0x%lx, PVPE %ld PTC %ld M %ld\n", val,
258 	       (val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT,
259 	       val & MVPCONF0_PTC, (val & MVPCONF0_M) >> MVPCONF0_M_SHIFT);
260 }
261 
262 /* Find some VPE program space  */
263 static void *alloc_progmem(unsigned long len)
264 {
265 	void *addr;
266 
267 #ifdef CONFIG_MIPS_VPE_LOADER_TOM
268 	/*
269 	 * This means you must tell Linux to use less memory than you
270 	 * physically have, for example by passing a mem= boot argument.
271 	 */
272 	addr = pfn_to_kaddr(max_low_pfn);
273 	memset(addr, 0, len);
274 #else
275 	/* simple grab some mem for now */
276 	addr = kzalloc(len, GFP_KERNEL);
277 #endif
278 
279 	return addr;
280 }
281 
282 static void release_progmem(void *ptr)
283 {
284 #ifndef CONFIG_MIPS_VPE_LOADER_TOM
285 	kfree(ptr);
286 #endif
287 }
288 
289 /* Update size with this section: return offset. */
290 static long get_offset(unsigned long *size, Elf_Shdr * sechdr)
291 {
292 	long ret;
293 
294 	ret = ALIGN(*size, sechdr->sh_addralign ? : 1);
295 	*size = ret + sechdr->sh_size;
296 	return ret;
297 }
298 
299 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
300    might -- code, read-only data, read-write data, small data.  Tally
301    sizes, and place the offsets into sh_entsize fields: high bit means it
302    belongs in init. */
303 static void layout_sections(struct module *mod, const Elf_Ehdr * hdr,
304 			    Elf_Shdr * sechdrs, const char *secstrings)
305 {
306 	static unsigned long const masks[][2] = {
307 		/* NOTE: all executable code must be the first section
308 		 * in this array; otherwise modify the text_size
309 		 * finder in the two loops below */
310 		{SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL},
311 		{SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL},
312 		{SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL},
313 		{ARCH_SHF_SMALL | SHF_ALLOC, 0}
314 	};
315 	unsigned int m, i;
316 
317 	for (i = 0; i < hdr->e_shnum; i++)
318 		sechdrs[i].sh_entsize = ~0UL;
319 
320 	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
321 		for (i = 0; i < hdr->e_shnum; ++i) {
322 			Elf_Shdr *s = &sechdrs[i];
323 
324 			//  || strncmp(secstrings + s->sh_name, ".init", 5) == 0)
325 			if ((s->sh_flags & masks[m][0]) != masks[m][0]
326 			    || (s->sh_flags & masks[m][1])
327 			    || s->sh_entsize != ~0UL)
328 				continue;
329 			s->sh_entsize = get_offset(&mod->core_size, s);
330 		}
331 
332 		if (m == 0)
333 			mod->core_text_size = mod->core_size;
334 
335 	}
336 }
337 
338 
339 /* from module-elf32.c, but subverted a little */
340 
341 struct mips_hi16 {
342 	struct mips_hi16 *next;
343 	Elf32_Addr *addr;
344 	Elf32_Addr value;
345 };
346 
347 static struct mips_hi16 *mips_hi16_list;
348 static unsigned int gp_offs, gp_addr;
349 
350 static int apply_r_mips_none(struct module *me, uint32_t *location,
351 			     Elf32_Addr v)
352 {
353 	return 0;
354 }
355 
356 static int apply_r_mips_gprel16(struct module *me, uint32_t *location,
357 				Elf32_Addr v)
358 {
359 	int rel;
360 
361 	if( !(*location & 0xffff) ) {
362 		rel = (int)v - gp_addr;
363 	}
364 	else {
365 		/* .sbss + gp(relative) + offset */
366 		/* kludge! */
367 		rel =  (int)(short)((int)v + gp_offs +
368 				    (int)(short)(*location & 0xffff) - gp_addr);
369 	}
370 
371 	if( (rel > 32768) || (rel < -32768) ) {
372 		printk(KERN_DEBUG "VPE loader: apply_r_mips_gprel16: "
373 		       "relative address 0x%x out of range of gp register\n",
374 		       rel);
375 		return -ENOEXEC;
376 	}
377 
378 	*location = (*location & 0xffff0000) | (rel & 0xffff);
379 
380 	return 0;
381 }
382 
383 static int apply_r_mips_pc16(struct module *me, uint32_t *location,
384 			     Elf32_Addr v)
385 {
386 	int rel;
387 	rel = (((unsigned int)v - (unsigned int)location));
388 	rel >>= 2;		// because the offset is in _instructions_ not bytes.
389 	rel -= 1;		// and one instruction less due to the branch delay slot.
390 
391 	if( (rel > 32768) || (rel < -32768) ) {
392 		printk(KERN_DEBUG "VPE loader: "
393  		       "apply_r_mips_pc16: relative address out of range 0x%x\n", rel);
394 		return -ENOEXEC;
395 	}
396 
397 	*location = (*location & 0xffff0000) | (rel & 0xffff);
398 
399 	return 0;
400 }
401 
402 static int apply_r_mips_32(struct module *me, uint32_t *location,
403 			   Elf32_Addr v)
404 {
405 	*location += v;
406 
407 	return 0;
408 }
409 
410 static int apply_r_mips_26(struct module *me, uint32_t *location,
411 			   Elf32_Addr v)
412 {
413 	if (v % 4) {
414 		printk(KERN_DEBUG "VPE loader: apply_r_mips_26 "
415 		       " unaligned relocation\n");
416 		return -ENOEXEC;
417 	}
418 
419 /*
420  * Not desperately convinced this is a good check of an overflow condition
421  * anyway. But it gets in the way of handling undefined weak symbols which
422  * we want to set to zero.
423  * if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
424  * printk(KERN_ERR
425  * "module %s: relocation overflow\n",
426  * me->name);
427  * return -ENOEXEC;
428  * }
429  */
430 
431 	*location = (*location & ~0x03ffffff) |
432 		((*location + (v >> 2)) & 0x03ffffff);
433 	return 0;
434 }
435 
436 static int apply_r_mips_hi16(struct module *me, uint32_t *location,
437 			     Elf32_Addr v)
438 {
439 	struct mips_hi16 *n;
440 
441 	/*
442 	 * We cannot relocate this one now because we don't know the value of
443 	 * the carry we need to add.  Save the information, and let LO16 do the
444 	 * actual relocation.
445 	 */
446 	n = kmalloc(sizeof *n, GFP_KERNEL);
447 	if (!n)
448 		return -ENOMEM;
449 
450 	n->addr = location;
451 	n->value = v;
452 	n->next = mips_hi16_list;
453 	mips_hi16_list = n;
454 
455 	return 0;
456 }
457 
458 static int apply_r_mips_lo16(struct module *me, uint32_t *location,
459 			     Elf32_Addr v)
460 {
461 	unsigned long insnlo = *location;
462 	Elf32_Addr val, vallo;
463 
464 	/* Sign extend the addend we extract from the lo insn.  */
465 	vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
466 
467 	if (mips_hi16_list != NULL) {
468 		struct mips_hi16 *l;
469 
470 		l = mips_hi16_list;
471 		while (l != NULL) {
472 			struct mips_hi16 *next;
473 			unsigned long insn;
474 
475 			/*
476 			 * The value for the HI16 had best be the same.
477 			 */
478  			if (v != l->value) {
479 				printk(KERN_DEBUG "VPE loader: "
480 				       "apply_r_mips_lo16/hi16: \t"
481 				       "inconsistent value information\n");
482 				return -ENOEXEC;
483 			}
484 
485 			/*
486 			 * Do the HI16 relocation.  Note that we actually don't
487 			 * need to know anything about the LO16 itself, except
488 			 * where to find the low 16 bits of the addend needed
489 			 * by the LO16.
490 			 */
491 			insn = *l->addr;
492 			val = ((insn & 0xffff) << 16) + vallo;
493 			val += v;
494 
495 			/*
496 			 * Account for the sign extension that will happen in
497 			 * the low bits.
498 			 */
499 			val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
500 
501 			insn = (insn & ~0xffff) | val;
502 			*l->addr = insn;
503 
504 			next = l->next;
505 			kfree(l);
506 			l = next;
507 		}
508 
509 		mips_hi16_list = NULL;
510 	}
511 
512 	/*
513 	 * Ok, we're done with the HI16 relocs.  Now deal with the LO16.
514 	 */
515 	val = v + vallo;
516 	insnlo = (insnlo & ~0xffff) | (val & 0xffff);
517 	*location = insnlo;
518 
519 	return 0;
520 }
521 
522 static int (*reloc_handlers[]) (struct module *me, uint32_t *location,
523 				Elf32_Addr v) = {
524 	[R_MIPS_NONE]	= apply_r_mips_none,
525 	[R_MIPS_32]	= apply_r_mips_32,
526 	[R_MIPS_26]	= apply_r_mips_26,
527 	[R_MIPS_HI16]	= apply_r_mips_hi16,
528 	[R_MIPS_LO16]	= apply_r_mips_lo16,
529 	[R_MIPS_GPREL16] = apply_r_mips_gprel16,
530 	[R_MIPS_PC16] = apply_r_mips_pc16
531 };
532 
533 static char *rstrs[] = {
534 	[R_MIPS_NONE]	= "MIPS_NONE",
535 	[R_MIPS_32]	= "MIPS_32",
536 	[R_MIPS_26]	= "MIPS_26",
537 	[R_MIPS_HI16]	= "MIPS_HI16",
538 	[R_MIPS_LO16]	= "MIPS_LO16",
539 	[R_MIPS_GPREL16] = "MIPS_GPREL16",
540 	[R_MIPS_PC16] = "MIPS_PC16"
541 };
542 
543 int apply_relocations(Elf32_Shdr *sechdrs,
544 		      const char *strtab,
545 		      unsigned int symindex,
546 		      unsigned int relsec,
547 		      struct module *me)
548 {
549 	Elf32_Rel *rel = (void *) sechdrs[relsec].sh_addr;
550 	Elf32_Sym *sym;
551 	uint32_t *location;
552 	unsigned int i;
553 	Elf32_Addr v;
554 	int res;
555 
556 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
557 		Elf32_Word r_info = rel[i].r_info;
558 
559 		/* This is where to make the change */
560 		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
561 			+ rel[i].r_offset;
562 		/* This is the symbol it is referring to */
563 		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
564 			+ ELF32_R_SYM(r_info);
565 
566 		if (!sym->st_value) {
567 			printk(KERN_DEBUG "%s: undefined weak symbol %s\n",
568 			       me->name, strtab + sym->st_name);
569 			/* just print the warning, dont barf */
570 		}
571 
572 		v = sym->st_value;
573 
574 		res = reloc_handlers[ELF32_R_TYPE(r_info)](me, location, v);
575 		if( res ) {
576 			char *r = rstrs[ELF32_R_TYPE(r_info)];
577 		    	printk(KERN_WARNING "VPE loader: .text+0x%x "
578 			       "relocation type %s for symbol \"%s\" failed\n",
579 			       rel[i].r_offset, r ? r : "UNKNOWN",
580 			       strtab + sym->st_name);
581 			return res;
582 		}
583 	}
584 
585 	return 0;
586 }
587 
588 void save_gp_address(unsigned int secbase, unsigned int rel)
589 {
590 	gp_addr = secbase + rel;
591 	gp_offs = gp_addr - (secbase & 0xffff0000);
592 }
593 /* end module-elf32.c */
594 
595 
596 
597 /* Change all symbols so that sh_value encodes the pointer directly. */
598 static void simplify_symbols(Elf_Shdr * sechdrs,
599 			    unsigned int symindex,
600 			    const char *strtab,
601 			    const char *secstrings,
602 			    unsigned int nsecs, struct module *mod)
603 {
604 	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
605 	unsigned long secbase, bssbase = 0;
606 	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
607 	int size;
608 
609 	/* find the .bss section for COMMON symbols */
610 	for (i = 0; i < nsecs; i++) {
611 		if (strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) == 0) {
612 			bssbase = sechdrs[i].sh_addr;
613 			break;
614 		}
615 	}
616 
617 	for (i = 1; i < n; i++) {
618 		switch (sym[i].st_shndx) {
619 		case SHN_COMMON:
620 			/* Allocate space for the symbol in the .bss section.
621 			   st_value is currently size.
622 			   We want it to have the address of the symbol. */
623 
624 			size = sym[i].st_value;
625 			sym[i].st_value = bssbase;
626 
627 			bssbase += size;
628 			break;
629 
630 		case SHN_ABS:
631 			/* Don't need to do anything */
632 			break;
633 
634 		case SHN_UNDEF:
635 			/* ret = -ENOENT; */
636 			break;
637 
638 		case SHN_MIPS_SCOMMON:
639 			printk(KERN_DEBUG "simplify_symbols: ignoring SHN_MIPS_SCOMMON "
640 			       "symbol <%s> st_shndx %d\n", strtab + sym[i].st_name,
641 			       sym[i].st_shndx);
642 			// .sbss section
643 			break;
644 
645 		default:
646 			secbase = sechdrs[sym[i].st_shndx].sh_addr;
647 
648 			if (strncmp(strtab + sym[i].st_name, "_gp", 3) == 0) {
649 				save_gp_address(secbase, sym[i].st_value);
650 			}
651 
652 			sym[i].st_value += secbase;
653 			break;
654 		}
655 	}
656 }
657 
658 #ifdef DEBUG_ELFLOADER
659 static void dump_elfsymbols(Elf_Shdr * sechdrs, unsigned int symindex,
660 			    const char *strtab, struct module *mod)
661 {
662 	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
663 	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
664 
665 	printk(KERN_DEBUG "dump_elfsymbols: n %d\n", n);
666 	for (i = 1; i < n; i++) {
667 		printk(KERN_DEBUG " i %d name <%s> 0x%x\n", i,
668 		       strtab + sym[i].st_name, sym[i].st_value);
669 	}
670 }
671 #endif
672 
673 /* We are prepared so configure and start the VPE... */
674 static int vpe_run(struct vpe * v)
675 {
676 	unsigned long flags, val, dmt_flag;
677 	struct vpe_notifications *n;
678 	unsigned int vpeflags;
679 	struct tc *t;
680 
681 	/* check we are the Master VPE */
682 	local_irq_save(flags);
683 	val = read_c0_vpeconf0();
684 	if (!(val & VPECONF0_MVP)) {
685 		printk(KERN_WARNING
686 		       "VPE loader: only Master VPE's are allowed to configure MT\n");
687 		local_irq_restore(flags);
688 
689 		return -1;
690 	}
691 
692 	dmt_flag = dmt();
693 	vpeflags = dvpe();
694 
695 	if (!list_empty(&v->tc)) {
696 		if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
697 			evpe(vpeflags);
698 			emt(dmt_flag);
699 			local_irq_restore(flags);
700 
701 			printk(KERN_WARNING
702 			       "VPE loader: TC %d is already in use.\n",
703                                t->index);
704 			return -ENOEXEC;
705 		}
706 	} else {
707 		evpe(vpeflags);
708 		emt(dmt_flag);
709 		local_irq_restore(flags);
710 
711 		printk(KERN_WARNING
712 		       "VPE loader: No TC's associated with VPE %d\n",
713 		       v->minor);
714 
715 		return -ENOEXEC;
716 	}
717 
718 	/* Put MVPE's into 'configuration state' */
719 	set_c0_mvpcontrol(MVPCONTROL_VPC);
720 
721 	settc(t->index);
722 
723 	/* should check it is halted, and not activated */
724 	if ((read_tc_c0_tcstatus() & TCSTATUS_A) || !(read_tc_c0_tchalt() & TCHALT_H)) {
725 		evpe(vpeflags);
726 		emt(dmt_flag);
727 		local_irq_restore(flags);
728 
729 		printk(KERN_WARNING "VPE loader: TC %d is already active!\n",
730 		       t->index);
731 
732 		return -ENOEXEC;
733 	}
734 
735 	/* Write the address we want it to start running from in the TCPC register. */
736 	write_tc_c0_tcrestart((unsigned long)v->__start);
737 	write_tc_c0_tccontext((unsigned long)0);
738 
739 	/*
740 	 * Mark the TC as activated, not interrupt exempt and not dynamically
741 	 * allocatable
742 	 */
743 	val = read_tc_c0_tcstatus();
744 	val = (val & ~(TCSTATUS_DA | TCSTATUS_IXMT)) | TCSTATUS_A;
745 	write_tc_c0_tcstatus(val);
746 
747 	write_tc_c0_tchalt(read_tc_c0_tchalt() & ~TCHALT_H);
748 
749 	/*
750 	 * The sde-kit passes 'memsize' to __start in $a3, so set something
751 	 * here...  Or set $a3 to zero and define DFLT_STACK_SIZE and
752 	 * DFLT_HEAP_SIZE when you compile your program
753 	 */
754 	mttgpr(6, v->ntcs);
755 	mttgpr(7, physical_memsize);
756 
757 	/* set up VPE1 */
758 	/*
759 	 * bind the TC to VPE 1 as late as possible so we only have the final
760 	 * VPE registers to set up, and so an EJTAG probe can trigger on it
761 	 */
762 	write_tc_c0_tcbind((read_tc_c0_tcbind() & ~TCBIND_CURVPE) | 1);
763 
764 	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~(VPECONF0_VPA));
765 
766 	back_to_back_c0_hazard();
767 
768 	/* Set up the XTC bit in vpeconf0 to point at our tc */
769 	write_vpe_c0_vpeconf0( (read_vpe_c0_vpeconf0() & ~(VPECONF0_XTC))
770 	                      | (t->index << VPECONF0_XTC_SHIFT));
771 
772 	back_to_back_c0_hazard();
773 
774 	/* enable this VPE */
775 	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA);
776 
777 	/* clear out any left overs from a previous program */
778 	write_vpe_c0_status(0);
779 	write_vpe_c0_cause(0);
780 
781 	/* take system out of configuration state */
782 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
783 
784 	/*
785 	 * SMTC/SMVP kernels manage VPE enable independently,
786 	 * but uniprocessor kernels need to turn it on, even
787 	 * if that wasn't the pre-dvpe() state.
788 	 */
789 #ifdef CONFIG_SMP
790 	evpe(vpeflags);
791 #else
792 	evpe(EVPE_ENABLE);
793 #endif
794 	emt(dmt_flag);
795 	local_irq_restore(flags);
796 
797 	list_for_each_entry(n, &v->notify, list)
798 		n->start(minor);
799 
800 	return 0;
801 }
802 
803 static int find_vpe_symbols(struct vpe * v, Elf_Shdr * sechdrs,
804 				      unsigned int symindex, const char *strtab,
805 				      struct module *mod)
806 {
807 	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
808 	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
809 
810 	for (i = 1; i < n; i++) {
811 		if (strcmp(strtab + sym[i].st_name, "__start") == 0) {
812 			v->__start = sym[i].st_value;
813 		}
814 
815 		if (strcmp(strtab + sym[i].st_name, "vpe_shared") == 0) {
816 			v->shared_ptr = (void *)sym[i].st_value;
817 		}
818 	}
819 
820 	if ( (v->__start == 0) || (v->shared_ptr == NULL))
821 		return -1;
822 
823 	return 0;
824 }
825 
826 /*
827  * Allocates a VPE with some program code space(the load address), copies the
828  * contents of the program (p)buffer performing relocatations/etc, free's it
829  * when finished.
830  */
831 static int vpe_elfload(struct vpe * v)
832 {
833 	Elf_Ehdr *hdr;
834 	Elf_Shdr *sechdrs;
835 	long err = 0;
836 	char *secstrings, *strtab = NULL;
837 	unsigned int len, i, symindex = 0, strindex = 0, relocate = 0;
838 	struct module mod;	// so we can re-use the relocations code
839 
840 	memset(&mod, 0, sizeof(struct module));
841 	strcpy(mod.name, "VPE loader");
842 
843 	hdr = (Elf_Ehdr *) v->pbuffer;
844 	len = v->plen;
845 
846 	/* Sanity checks against insmoding binaries or wrong arch,
847 	   weird elf version */
848 	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
849 	    || (hdr->e_type != ET_REL && hdr->e_type != ET_EXEC)
850 	    || !elf_check_arch(hdr)
851 	    || hdr->e_shentsize != sizeof(*sechdrs)) {
852 		printk(KERN_WARNING
853 		       "VPE loader: program wrong arch or weird elf version\n");
854 
855 		return -ENOEXEC;
856 	}
857 
858 	if (hdr->e_type == ET_REL)
859 		relocate = 1;
860 
861 	if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
862 		printk(KERN_ERR "VPE loader: program length %u truncated\n",
863 		       len);
864 
865 		return -ENOEXEC;
866 	}
867 
868 	/* Convenience variables */
869 	sechdrs = (void *)hdr + hdr->e_shoff;
870 	secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
871 	sechdrs[0].sh_addr = 0;
872 
873 	/* And these should exist, but gcc whinges if we don't init them */
874 	symindex = strindex = 0;
875 
876 	if (relocate) {
877 		for (i = 1; i < hdr->e_shnum; i++) {
878 			if (sechdrs[i].sh_type != SHT_NOBITS
879 			    && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) {
880 				printk(KERN_ERR "VPE program length %u truncated\n",
881 				       len);
882 				return -ENOEXEC;
883 			}
884 
885 			/* Mark all sections sh_addr with their address in the
886 			   temporary image. */
887 			sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
888 
889 			/* Internal symbols and strings. */
890 			if (sechdrs[i].sh_type == SHT_SYMTAB) {
891 				symindex = i;
892 				strindex = sechdrs[i].sh_link;
893 				strtab = (char *)hdr + sechdrs[strindex].sh_offset;
894 			}
895 		}
896 		layout_sections(&mod, hdr, sechdrs, secstrings);
897 	}
898 
899 	v->load_addr = alloc_progmem(mod.core_size);
900 	if (!v->load_addr)
901 		return -ENOMEM;
902 
903 	pr_info("VPE loader: loading to %p\n", v->load_addr);
904 
905 	if (relocate) {
906 		for (i = 0; i < hdr->e_shnum; i++) {
907 			void *dest;
908 
909 			if (!(sechdrs[i].sh_flags & SHF_ALLOC))
910 				continue;
911 
912 			dest = v->load_addr + sechdrs[i].sh_entsize;
913 
914 			if (sechdrs[i].sh_type != SHT_NOBITS)
915 				memcpy(dest, (void *)sechdrs[i].sh_addr,
916 				       sechdrs[i].sh_size);
917 			/* Update sh_addr to point to copy in image. */
918 			sechdrs[i].sh_addr = (unsigned long)dest;
919 
920 			printk(KERN_DEBUG " section sh_name %s sh_addr 0x%x\n",
921 			       secstrings + sechdrs[i].sh_name, sechdrs[i].sh_addr);
922 		}
923 
924  		/* Fix up syms, so that st_value is a pointer to location. */
925  		simplify_symbols(sechdrs, symindex, strtab, secstrings,
926  				 hdr->e_shnum, &mod);
927 
928  		/* Now do relocations. */
929  		for (i = 1; i < hdr->e_shnum; i++) {
930  			const char *strtab = (char *)sechdrs[strindex].sh_addr;
931  			unsigned int info = sechdrs[i].sh_info;
932 
933  			/* Not a valid relocation section? */
934  			if (info >= hdr->e_shnum)
935  				continue;
936 
937  			/* Don't bother with non-allocated sections */
938  			if (!(sechdrs[info].sh_flags & SHF_ALLOC))
939  				continue;
940 
941  			if (sechdrs[i].sh_type == SHT_REL)
942  				err = apply_relocations(sechdrs, strtab, symindex, i,
943  							&mod);
944  			else if (sechdrs[i].sh_type == SHT_RELA)
945  				err = apply_relocate_add(sechdrs, strtab, symindex, i,
946  							 &mod);
947  			if (err < 0)
948  				return err;
949 
950   		}
951   	} else {
952 		struct elf_phdr *phdr = (struct elf_phdr *) ((char *)hdr + hdr->e_phoff);
953 
954 		for (i = 0; i < hdr->e_phnum; i++) {
955 			if (phdr->p_type == PT_LOAD) {
956 				memcpy((void *)phdr->p_paddr,
957 				       (char *)hdr + phdr->p_offset,
958 				       phdr->p_filesz);
959 				memset((void *)phdr->p_paddr + phdr->p_filesz,
960 				       0, phdr->p_memsz - phdr->p_filesz);
961 		    }
962 		    phdr++;
963 		}
964 
965 		for (i = 0; i < hdr->e_shnum; i++) {
966  			/* Internal symbols and strings. */
967  			if (sechdrs[i].sh_type == SHT_SYMTAB) {
968  				symindex = i;
969  				strindex = sechdrs[i].sh_link;
970  				strtab = (char *)hdr + sechdrs[strindex].sh_offset;
971 
972  				/* mark the symtab's address for when we try to find the
973  				   magic symbols */
974  				sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
975  			}
976 		}
977 	}
978 
979 	/* make sure it's physically written out */
980 	flush_icache_range((unsigned long)v->load_addr,
981 			   (unsigned long)v->load_addr + v->len);
982 
983 	if ((find_vpe_symbols(v, sechdrs, symindex, strtab, &mod)) < 0) {
984 		if (v->__start == 0) {
985 			printk(KERN_WARNING "VPE loader: program does not contain "
986 			       "a __start symbol\n");
987 			return -ENOEXEC;
988 		}
989 
990 		if (v->shared_ptr == NULL)
991 			printk(KERN_WARNING "VPE loader: "
992 			       "program does not contain vpe_shared symbol.\n"
993 			       " Unable to use AMVP (AP/SP) facilities.\n");
994 	}
995 
996 	printk(" elf loaded\n");
997 	return 0;
998 }
999 
1000 static void cleanup_tc(struct tc *tc)
1001 {
1002 	unsigned long flags;
1003 	unsigned int mtflags, vpflags;
1004 	int tmp;
1005 
1006 	local_irq_save(flags);
1007 	mtflags = dmt();
1008 	vpflags = dvpe();
1009 	/* Put MVPE's into 'configuration state' */
1010 	set_c0_mvpcontrol(MVPCONTROL_VPC);
1011 
1012 	settc(tc->index);
1013 	tmp = read_tc_c0_tcstatus();
1014 
1015 	/* mark not allocated and not dynamically allocatable */
1016 	tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1017 	tmp |= TCSTATUS_IXMT;	/* interrupt exempt */
1018 	write_tc_c0_tcstatus(tmp);
1019 
1020 	write_tc_c0_tchalt(TCHALT_H);
1021 	mips_ihb();
1022 
1023 	/* bind it to anything other than VPE1 */
1024 //	write_tc_c0_tcbind(read_tc_c0_tcbind() & ~TCBIND_CURVPE); // | TCBIND_CURVPE
1025 
1026 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1027 	evpe(vpflags);
1028 	emt(mtflags);
1029 	local_irq_restore(flags);
1030 }
1031 
1032 static int getcwd(char *buff, int size)
1033 {
1034 	mm_segment_t old_fs;
1035 	int ret;
1036 
1037 	old_fs = get_fs();
1038 	set_fs(KERNEL_DS);
1039 
1040 	ret = sys_getcwd(buff, size);
1041 
1042 	set_fs(old_fs);
1043 
1044 	return ret;
1045 }
1046 
1047 /* checks VPE is unused and gets ready to load program  */
1048 static int vpe_open(struct inode *inode, struct file *filp)
1049 {
1050 	enum vpe_state state;
1051 	struct vpe_notifications *not;
1052 	struct vpe *v;
1053 	int ret;
1054 
1055 	if (minor != iminor(inode)) {
1056 		/* assume only 1 device at the moment. */
1057 		printk(KERN_WARNING "VPE loader: only vpe1 is supported\n");
1058 		return -ENODEV;
1059 	}
1060 
1061 	if ((v = get_vpe(tclimit)) == NULL) {
1062 		printk(KERN_WARNING "VPE loader: unable to get vpe\n");
1063 		return -ENODEV;
1064 	}
1065 
1066 	state = xchg(&v->state, VPE_STATE_INUSE);
1067 	if (state != VPE_STATE_UNUSED) {
1068 		printk(KERN_DEBUG "VPE loader: tc in use dumping regs\n");
1069 
1070 		list_for_each_entry(not, &v->notify, list) {
1071 			not->stop(tclimit);
1072 		}
1073 
1074 		release_progmem(v->load_addr);
1075 		cleanup_tc(get_tc(tclimit));
1076 	}
1077 
1078 	/* this of-course trashes what was there before... */
1079 	v->pbuffer = vmalloc(P_SIZE);
1080 	v->plen = P_SIZE;
1081 	v->load_addr = NULL;
1082 	v->len = 0;
1083 
1084 	v->uid = filp->f_uid;
1085 	v->gid = filp->f_gid;
1086 
1087 #ifdef CONFIG_MIPS_APSP_KSPD
1088 	/* get kspd to tell us when a syscall_exit happens */
1089 	if (!kspd_events_reqd) {
1090 		kspd_notify(&kspd_events);
1091 		kspd_events_reqd++;
1092 	}
1093 #endif
1094 
1095 	v->cwd[0] = 0;
1096 	ret = getcwd(v->cwd, VPE_PATH_MAX);
1097 	if (ret < 0)
1098 		printk(KERN_WARNING "VPE loader: open, getcwd returned %d\n", ret);
1099 
1100 	v->shared_ptr = NULL;
1101 	v->__start = 0;
1102 
1103 	return 0;
1104 }
1105 
1106 static int vpe_release(struct inode *inode, struct file *filp)
1107 {
1108 	struct vpe *v;
1109 	Elf_Ehdr *hdr;
1110 	int ret = 0;
1111 
1112 	v = get_vpe(tclimit);
1113 	if (v == NULL)
1114 		return -ENODEV;
1115 
1116 	hdr = (Elf_Ehdr *) v->pbuffer;
1117 	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) == 0) {
1118 		if (vpe_elfload(v) >= 0) {
1119 			vpe_run(v);
1120 		} else {
1121  			printk(KERN_WARNING "VPE loader: ELF load failed.\n");
1122 			ret = -ENOEXEC;
1123 		}
1124 	} else {
1125  		printk(KERN_WARNING "VPE loader: only elf files are supported\n");
1126 		ret = -ENOEXEC;
1127 	}
1128 
1129 	/* It's good to be able to run the SP and if it chokes have a look at
1130 	   the /dev/rt?. But if we reset the pointer to the shared struct we
1131 	   loose what has happened. So perhaps if garbage is sent to the vpe
1132 	   device, use it as a trigger for the reset. Hopefully a nice
1133 	   executable will be along shortly. */
1134 	if (ret < 0)
1135 		v->shared_ptr = NULL;
1136 
1137 	// cleanup any temp buffers
1138 	if (v->pbuffer)
1139 		vfree(v->pbuffer);
1140 	v->plen = 0;
1141 	return ret;
1142 }
1143 
1144 static ssize_t vpe_write(struct file *file, const char __user * buffer,
1145 			 size_t count, loff_t * ppos)
1146 {
1147 	size_t ret = count;
1148 	struct vpe *v;
1149 
1150 	if (iminor(file->f_path.dentry->d_inode) != minor)
1151 		return -ENODEV;
1152 
1153 	v = get_vpe(tclimit);
1154 	if (v == NULL)
1155 		return -ENODEV;
1156 
1157 	if (v->pbuffer == NULL) {
1158 		printk(KERN_ERR "VPE loader: no buffer for program\n");
1159 		return -ENOMEM;
1160 	}
1161 
1162 	if ((count + v->len) > v->plen) {
1163 		printk(KERN_WARNING
1164 		       "VPE loader: elf size too big. Perhaps strip uneeded symbols\n");
1165 		return -ENOMEM;
1166 	}
1167 
1168 	count -= copy_from_user(v->pbuffer + v->len, buffer, count);
1169 	if (!count)
1170 		return -EFAULT;
1171 
1172 	v->len += count;
1173 	return ret;
1174 }
1175 
1176 static const struct file_operations vpe_fops = {
1177 	.owner = THIS_MODULE,
1178 	.open = vpe_open,
1179 	.release = vpe_release,
1180 	.write = vpe_write
1181 };
1182 
1183 /* module wrapper entry points */
1184 /* give me a vpe */
1185 vpe_handle vpe_alloc(void)
1186 {
1187 	int i;
1188 	struct vpe *v;
1189 
1190 	/* find a vpe */
1191 	for (i = 1; i < MAX_VPES; i++) {
1192 		if ((v = get_vpe(i)) != NULL) {
1193 			v->state = VPE_STATE_INUSE;
1194 			return v;
1195 		}
1196 	}
1197 	return NULL;
1198 }
1199 
1200 EXPORT_SYMBOL(vpe_alloc);
1201 
1202 /* start running from here */
1203 int vpe_start(vpe_handle vpe, unsigned long start)
1204 {
1205 	struct vpe *v = vpe;
1206 
1207 	v->__start = start;
1208 	return vpe_run(v);
1209 }
1210 
1211 EXPORT_SYMBOL(vpe_start);
1212 
1213 /* halt it for now */
1214 int vpe_stop(vpe_handle vpe)
1215 {
1216 	struct vpe *v = vpe;
1217 	struct tc *t;
1218 	unsigned int evpe_flags;
1219 
1220 	evpe_flags = dvpe();
1221 
1222 	if ((t = list_entry(v->tc.next, struct tc, tc)) != NULL) {
1223 
1224 		settc(t->index);
1225 		write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1226 	}
1227 
1228 	evpe(evpe_flags);
1229 
1230 	return 0;
1231 }
1232 
1233 EXPORT_SYMBOL(vpe_stop);
1234 
1235 /* I've done with it thank you */
1236 int vpe_free(vpe_handle vpe)
1237 {
1238 	struct vpe *v = vpe;
1239 	struct tc *t;
1240 	unsigned int evpe_flags;
1241 
1242 	if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
1243 		return -ENOEXEC;
1244 	}
1245 
1246 	evpe_flags = dvpe();
1247 
1248 	/* Put MVPE's into 'configuration state' */
1249 	set_c0_mvpcontrol(MVPCONTROL_VPC);
1250 
1251 	settc(t->index);
1252 	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1253 
1254 	/* halt the TC */
1255 	write_tc_c0_tchalt(TCHALT_H);
1256 	mips_ihb();
1257 
1258 	/* mark the TC unallocated */
1259 	write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A);
1260 
1261 	v->state = VPE_STATE_UNUSED;
1262 
1263 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1264 	evpe(evpe_flags);
1265 
1266 	return 0;
1267 }
1268 
1269 EXPORT_SYMBOL(vpe_free);
1270 
1271 void *vpe_get_shared(int index)
1272 {
1273 	struct vpe *v;
1274 
1275 	if ((v = get_vpe(index)) == NULL)
1276 		return NULL;
1277 
1278 	return v->shared_ptr;
1279 }
1280 
1281 EXPORT_SYMBOL(vpe_get_shared);
1282 
1283 int vpe_getuid(int index)
1284 {
1285 	struct vpe *v;
1286 
1287 	if ((v = get_vpe(index)) == NULL)
1288 		return -1;
1289 
1290 	return v->uid;
1291 }
1292 
1293 EXPORT_SYMBOL(vpe_getuid);
1294 
1295 int vpe_getgid(int index)
1296 {
1297 	struct vpe *v;
1298 
1299 	if ((v = get_vpe(index)) == NULL)
1300 		return -1;
1301 
1302 	return v->gid;
1303 }
1304 
1305 EXPORT_SYMBOL(vpe_getgid);
1306 
1307 int vpe_notify(int index, struct vpe_notifications *notify)
1308 {
1309 	struct vpe *v;
1310 
1311 	if ((v = get_vpe(index)) == NULL)
1312 		return -1;
1313 
1314 	list_add(&notify->list, &v->notify);
1315 	return 0;
1316 }
1317 
1318 EXPORT_SYMBOL(vpe_notify);
1319 
1320 char *vpe_getcwd(int index)
1321 {
1322 	struct vpe *v;
1323 
1324 	if ((v = get_vpe(index)) == NULL)
1325 		return NULL;
1326 
1327 	return v->cwd;
1328 }
1329 
1330 EXPORT_SYMBOL(vpe_getcwd);
1331 
1332 #ifdef CONFIG_MIPS_APSP_KSPD
1333 static void kspd_sp_exit( int sp_id)
1334 {
1335 	cleanup_tc(get_tc(sp_id));
1336 }
1337 #endif
1338 
1339 static ssize_t store_kill(struct device *dev, struct device_attribute *attr,
1340 			  const char *buf, size_t len)
1341 {
1342 	struct vpe *vpe = get_vpe(tclimit);
1343 	struct vpe_notifications *not;
1344 
1345 	list_for_each_entry(not, &vpe->notify, list) {
1346 		not->stop(tclimit);
1347 	}
1348 
1349 	release_progmem(vpe->load_addr);
1350 	cleanup_tc(get_tc(tclimit));
1351 	vpe_stop(vpe);
1352 	vpe_free(vpe);
1353 
1354 	return len;
1355 }
1356 
1357 static ssize_t show_ntcs(struct device *cd, struct device_attribute *attr,
1358 			 char *buf)
1359 {
1360 	struct vpe *vpe = get_vpe(tclimit);
1361 
1362 	return sprintf(buf, "%d\n", vpe->ntcs);
1363 }
1364 
1365 static ssize_t store_ntcs(struct device *dev, struct device_attribute *attr,
1366 			  const char *buf, size_t len)
1367 {
1368 	struct vpe *vpe = get_vpe(tclimit);
1369 	unsigned long new;
1370 	char *endp;
1371 
1372 	new = simple_strtoul(buf, &endp, 0);
1373 	if (endp == buf)
1374 		goto out_einval;
1375 
1376 	if (new == 0 || new > (hw_tcs - tclimit))
1377 		goto out_einval;
1378 
1379 	vpe->ntcs = new;
1380 
1381 	return len;
1382 
1383 out_einval:
1384 	return -EINVAL;;
1385 }
1386 
1387 static struct device_attribute vpe_class_attributes[] = {
1388 	__ATTR(kill, S_IWUSR, NULL, store_kill),
1389 	__ATTR(ntcs, S_IRUGO | S_IWUSR, show_ntcs, store_ntcs),
1390 	{}
1391 };
1392 
1393 static void vpe_device_release(struct device *cd)
1394 {
1395 	kfree(cd);
1396 }
1397 
1398 struct class vpe_class = {
1399 	.name = "vpe",
1400 	.owner = THIS_MODULE,
1401 	.dev_release = vpe_device_release,
1402 	.dev_attrs = vpe_class_attributes,
1403 };
1404 
1405 struct device vpe_device;
1406 
1407 static int __init vpe_module_init(void)
1408 {
1409 	unsigned int mtflags, vpflags;
1410 	unsigned long flags, val;
1411 	struct vpe *v = NULL;
1412 	struct tc *t;
1413 	int tc, err;
1414 
1415 	if (!cpu_has_mipsmt) {
1416 		printk("VPE loader: not a MIPS MT capable processor\n");
1417 		return -ENODEV;
1418 	}
1419 
1420 	if (vpelimit == 0) {
1421 		printk(KERN_WARNING "No VPEs reserved for AP/SP, not "
1422 		       "initializing VPE loader.\nPass maxvpes=<n> argument as "
1423 		       "kernel argument\n");
1424 
1425 		return -ENODEV;
1426 	}
1427 
1428 	if (tclimit == 0) {
1429 		printk(KERN_WARNING "No TCs reserved for AP/SP, not "
1430 		       "initializing VPE loader.\nPass maxtcs=<n> argument as "
1431 		       "kernel argument\n");
1432 
1433 		return -ENODEV;
1434 	}
1435 
1436 	major = register_chrdev(0, module_name, &vpe_fops);
1437 	if (major < 0) {
1438 		printk("VPE loader: unable to register character device\n");
1439 		return major;
1440 	}
1441 
1442 	err = class_register(&vpe_class);
1443 	if (err) {
1444 		printk(KERN_ERR "vpe_class registration failed\n");
1445 		goto out_chrdev;
1446 	}
1447 
1448 	device_initialize(&vpe_device);
1449 	vpe_device.class	= &vpe_class,
1450 	vpe_device.parent	= NULL,
1451 	strlcpy(vpe_device.bus_id, "vpe1", BUS_ID_SIZE);
1452 	vpe_device.devt = MKDEV(major, minor);
1453 	err = device_add(&vpe_device);
1454 	if (err) {
1455 		printk(KERN_ERR "Adding vpe_device failed\n");
1456 		goto out_class;
1457 	}
1458 
1459 	local_irq_save(flags);
1460 	mtflags = dmt();
1461 	vpflags = dvpe();
1462 
1463 	/* Put MVPE's into 'configuration state' */
1464 	set_c0_mvpcontrol(MVPCONTROL_VPC);
1465 
1466 	/* dump_mtregs(); */
1467 
1468 	val = read_c0_mvpconf0();
1469 	hw_tcs = (val & MVPCONF0_PTC) + 1;
1470 	hw_vpes = ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
1471 
1472 	for (tc = tclimit; tc < hw_tcs; tc++) {
1473 		/*
1474 		 * Must re-enable multithreading temporarily or in case we
1475 		 * reschedule send IPIs or similar we might hang.
1476 		 */
1477 		clear_c0_mvpcontrol(MVPCONTROL_VPC);
1478 		evpe(vpflags);
1479 		emt(mtflags);
1480 		local_irq_restore(flags);
1481 		t = alloc_tc(tc);
1482 		if (!t) {
1483 			err = -ENOMEM;
1484 			goto out;
1485 		}
1486 
1487 		local_irq_save(flags);
1488 		mtflags = dmt();
1489 		vpflags = dvpe();
1490 		set_c0_mvpcontrol(MVPCONTROL_VPC);
1491 
1492 		/* VPE's */
1493 		if (tc < hw_tcs) {
1494 			settc(tc);
1495 
1496 			if ((v = alloc_vpe(tc)) == NULL) {
1497 				printk(KERN_WARNING "VPE: unable to allocate VPE\n");
1498 
1499 				goto out_reenable;
1500 			}
1501 
1502 			v->ntcs = hw_tcs - tclimit;
1503 
1504 			/* add the tc to the list of this vpe's tc's. */
1505 			list_add(&t->tc, &v->tc);
1506 
1507 			/* deactivate all but vpe0 */
1508 			if (tc >= tclimit) {
1509 				unsigned long tmp = read_vpe_c0_vpeconf0();
1510 
1511 				tmp &= ~VPECONF0_VPA;
1512 
1513 				/* master VPE */
1514 				tmp |= VPECONF0_MVP;
1515 				write_vpe_c0_vpeconf0(tmp);
1516 			}
1517 
1518 			/* disable multi-threading with TC's */
1519 			write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE);
1520 
1521 			if (tc >= vpelimit) {
1522 				/*
1523 				 * Set config to be the same as vpe0,
1524 				 * particularly kseg0 coherency alg
1525 				 */
1526 				write_vpe_c0_config(read_c0_config());
1527 			}
1528 		}
1529 
1530 		/* TC's */
1531 		t->pvpe = v;	/* set the parent vpe */
1532 
1533 		if (tc >= tclimit) {
1534 			unsigned long tmp;
1535 
1536 			settc(tc);
1537 
1538 			/* Any TC that is bound to VPE0 gets left as is - in case
1539 			   we are running SMTC on VPE0. A TC that is bound to any
1540 			   other VPE gets bound to VPE0, ideally I'd like to make
1541 			   it homeless but it doesn't appear to let me bind a TC
1542 			   to a non-existent VPE. Which is perfectly reasonable.
1543 
1544 			   The (un)bound state is visible to an EJTAG probe so may
1545 			   notify GDB...
1546 			*/
1547 
1548 			if (((tmp = read_tc_c0_tcbind()) & TCBIND_CURVPE)) {
1549 				/* tc is bound >vpe0 */
1550 				write_tc_c0_tcbind(tmp & ~TCBIND_CURVPE);
1551 
1552 				t->pvpe = get_vpe(0);	/* set the parent vpe */
1553 			}
1554 
1555 			/* halt the TC */
1556 			write_tc_c0_tchalt(TCHALT_H);
1557 			mips_ihb();
1558 
1559 			tmp = read_tc_c0_tcstatus();
1560 
1561 			/* mark not activated and not dynamically allocatable */
1562 			tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1563 			tmp |= TCSTATUS_IXMT;	/* interrupt exempt */
1564 			write_tc_c0_tcstatus(tmp);
1565 		}
1566 	}
1567 
1568 out_reenable:
1569 	/* release config state */
1570 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1571 
1572 	evpe(vpflags);
1573 	emt(mtflags);
1574 	local_irq_restore(flags);
1575 
1576 #ifdef CONFIG_MIPS_APSP_KSPD
1577 	kspd_events.kspd_sp_exit = kspd_sp_exit;
1578 #endif
1579 	return 0;
1580 
1581 out_class:
1582 	class_unregister(&vpe_class);
1583 out_chrdev:
1584 	unregister_chrdev(major, module_name);
1585 
1586 out:
1587 	return err;
1588 }
1589 
1590 static void __exit vpe_module_exit(void)
1591 {
1592 	struct vpe *v, *n;
1593 
1594 	list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list) {
1595 		if (v->state != VPE_STATE_UNUSED) {
1596 			release_vpe(v);
1597 		}
1598 	}
1599 
1600 	device_del(&vpe_device);
1601 	unregister_chrdev(major, module_name);
1602 }
1603 
1604 module_init(vpe_module_init);
1605 module_exit(vpe_module_exit);
1606 MODULE_DESCRIPTION("MIPS VPE Loader");
1607 MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
1608 MODULE_LICENSE("GPL");
1609