xref: /openbmc/linux/arch/mips/kernel/vpe.c (revision bdf5d42c)
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 #include <asm/mips_mt.h>
57 
58 typedef 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 
67 /*
68  * The number of TCs and VPEs physically available on the core
69  */
70 static int hw_tcs, hw_vpes;
71 static char module_name[] = "vpe";
72 static int major;
73 static const int minor = 1;	/* fixed for now  */
74 
75 #ifdef CONFIG_MIPS_APSP_KSPD
76  static struct kspd_notifications kspd_events;
77 static int kspd_events_reqd = 0;
78 #endif
79 
80 /* grab the likely amount of memory we will need. */
81 #ifdef CONFIG_MIPS_VPE_LOADER_TOM
82 #define P_SIZE (2 * 1024 * 1024)
83 #else
84 /* add an overhead to the max kmalloc size for non-striped symbols/etc */
85 #define P_SIZE (256 * 1024)
86 #endif
87 
88 extern unsigned long physical_memsize;
89 
90 #define MAX_VPES 16
91 #define VPE_PATH_MAX 256
92 
93 enum vpe_state {
94 	VPE_STATE_UNUSED = 0,
95 	VPE_STATE_INUSE,
96 	VPE_STATE_RUNNING
97 };
98 
99 enum tc_state {
100 	TC_STATE_UNUSED = 0,
101 	TC_STATE_INUSE,
102 	TC_STATE_RUNNING,
103 	TC_STATE_DYNAMIC
104 };
105 
106 struct vpe {
107 	enum vpe_state state;
108 
109 	/* (device) minor associated with this vpe */
110 	int minor;
111 
112 	/* elfloader stuff */
113 	void *load_addr;
114 	unsigned long len;
115 	char *pbuffer;
116 	unsigned long plen;
117 	unsigned int uid, gid;
118 	char cwd[VPE_PATH_MAX];
119 
120 	unsigned long __start;
121 
122 	/* tc's associated with this vpe */
123 	struct list_head tc;
124 
125 	/* The list of vpe's */
126 	struct list_head list;
127 
128 	/* shared symbol address */
129 	void *shared_ptr;
130 
131 	/* the list of who wants to know when something major happens */
132 	struct list_head notify;
133 
134 	unsigned int ntcs;
135 };
136 
137 struct tc {
138 	enum tc_state state;
139 	int index;
140 
141 	struct vpe *pvpe;	/* parent VPE */
142 	struct list_head tc;	/* The list of TC's with this VPE */
143 	struct list_head list;	/* The global list of tc's */
144 };
145 
146 struct {
147 	/* Virtual processing elements */
148 	struct list_head vpe_list;
149 
150 	/* Thread contexts */
151 	struct list_head tc_list;
152 } vpecontrol = {
153 	.vpe_list = LIST_HEAD_INIT(vpecontrol.vpe_list),
154 	.tc_list = LIST_HEAD_INIT(vpecontrol.tc_list)
155 };
156 
157 static void release_progmem(void *ptr);
158 extern void save_gp_address(unsigned int secbase, unsigned int rel);
159 
160 /* get the vpe associated with this minor */
161 struct 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 */
177 struct 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 
189 struct 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) */
202 struct 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. */
219 struct tc *alloc_tc(int index)
220 {
221 	struct tc *tc;
222 
223 	if ((tc = kzalloc(sizeof(struct tc), GFP_KERNEL)) == NULL)
224 		goto out;
225 
226 	INIT_LIST_HEAD(&tc->tc);
227 	tc->index = index;
228 	list_add_tail(&tc->list, &vpecontrol.tc_list);
229 
230 out:
231 	return tc;
232 }
233 
234 /* clean up and free everything */
235 void release_vpe(struct vpe *v)
236 {
237 	list_del(&v->list);
238 	if (v->load_addr)
239 		release_progmem(v);
240 	kfree(v);
241 }
242 
243 void dump_mtregs(void)
244 {
245 	unsigned long val;
246 
247 	val = read_c0_config3();
248 	printk("config3 0x%lx MT %ld\n", val,
249 	       (val & CONFIG3_MT) >> CONFIG3_MT_SHIFT);
250 
251 	val = read_c0_mvpcontrol();
252 	printk("MVPControl 0x%lx, STLB %ld VPC %ld EVP %ld\n", val,
253 	       (val & MVPCONTROL_STLB) >> MVPCONTROL_STLB_SHIFT,
254 	       (val & MVPCONTROL_VPC) >> MVPCONTROL_VPC_SHIFT,
255 	       (val & MVPCONTROL_EVP));
256 
257 	val = read_c0_mvpconf0();
258 	printk("mvpconf0 0x%lx, PVPE %ld PTC %ld M %ld\n", val,
259 	       (val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT,
260 	       val & MVPCONF0_PTC, (val & MVPCONF0_M) >> MVPCONF0_M_SHIFT);
261 }
262 
263 /* Find some VPE program space  */
264 static void *alloc_progmem(unsigned long len)
265 {
266 #ifdef CONFIG_MIPS_VPE_LOADER_TOM
267 	/* this means you must tell linux to use less memory than you physically have */
268 	return pfn_to_kaddr(max_pfn);
269 #else
270 	// simple grab some mem for now
271 	return kmalloc(len, GFP_KERNEL);
272 #endif
273 }
274 
275 static void release_progmem(void *ptr)
276 {
277 #ifndef CONFIG_MIPS_VPE_LOADER_TOM
278 	kfree(ptr);
279 #endif
280 }
281 
282 /* Update size with this section: return offset. */
283 static long get_offset(unsigned long *size, Elf_Shdr * sechdr)
284 {
285 	long ret;
286 
287 	ret = ALIGN(*size, sechdr->sh_addralign ? : 1);
288 	*size = ret + sechdr->sh_size;
289 	return ret;
290 }
291 
292 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
293    might -- code, read-only data, read-write data, small data.  Tally
294    sizes, and place the offsets into sh_entsize fields: high bit means it
295    belongs in init. */
296 static void layout_sections(struct module *mod, const Elf_Ehdr * hdr,
297 			    Elf_Shdr * sechdrs, const char *secstrings)
298 {
299 	static unsigned long const masks[][2] = {
300 		/* NOTE: all executable code must be the first section
301 		 * in this array; otherwise modify the text_size
302 		 * finder in the two loops below */
303 		{SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL},
304 		{SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL},
305 		{SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL},
306 		{ARCH_SHF_SMALL | SHF_ALLOC, 0}
307 	};
308 	unsigned int m, i;
309 
310 	for (i = 0; i < hdr->e_shnum; i++)
311 		sechdrs[i].sh_entsize = ~0UL;
312 
313 	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
314 		for (i = 0; i < hdr->e_shnum; ++i) {
315 			Elf_Shdr *s = &sechdrs[i];
316 
317 			//  || strncmp(secstrings + s->sh_name, ".init", 5) == 0)
318 			if ((s->sh_flags & masks[m][0]) != masks[m][0]
319 			    || (s->sh_flags & masks[m][1])
320 			    || s->sh_entsize != ~0UL)
321 				continue;
322 			s->sh_entsize = get_offset(&mod->core_size, s);
323 		}
324 
325 		if (m == 0)
326 			mod->core_text_size = mod->core_size;
327 
328 	}
329 }
330 
331 
332 /* from module-elf32.c, but subverted a little */
333 
334 struct mips_hi16 {
335 	struct mips_hi16 *next;
336 	Elf32_Addr *addr;
337 	Elf32_Addr value;
338 };
339 
340 static struct mips_hi16 *mips_hi16_list;
341 static unsigned int gp_offs, gp_addr;
342 
343 static int apply_r_mips_none(struct module *me, uint32_t *location,
344 			     Elf32_Addr v)
345 {
346 	return 0;
347 }
348 
349 static int apply_r_mips_gprel16(struct module *me, uint32_t *location,
350 				Elf32_Addr v)
351 {
352 	int rel;
353 
354 	if( !(*location & 0xffff) ) {
355 		rel = (int)v - gp_addr;
356 	}
357 	else {
358 		/* .sbss + gp(relative) + offset */
359 		/* kludge! */
360 		rel =  (int)(short)((int)v + gp_offs +
361 				    (int)(short)(*location & 0xffff) - gp_addr);
362 	}
363 
364 	if( (rel > 32768) || (rel < -32768) ) {
365 		printk(KERN_DEBUG "VPE loader: apply_r_mips_gprel16: "
366 		       "relative address 0x%x out of range of gp register\n",
367 		       rel);
368 		return -ENOEXEC;
369 	}
370 
371 	*location = (*location & 0xffff0000) | (rel & 0xffff);
372 
373 	return 0;
374 }
375 
376 static int apply_r_mips_pc16(struct module *me, uint32_t *location,
377 			     Elf32_Addr v)
378 {
379 	int rel;
380 	rel = (((unsigned int)v - (unsigned int)location));
381 	rel >>= 2;		// because the offset is in _instructions_ not bytes.
382 	rel -= 1;		// and one instruction less due to the branch delay slot.
383 
384 	if( (rel > 32768) || (rel < -32768) ) {
385 		printk(KERN_DEBUG "VPE loader: "
386  		       "apply_r_mips_pc16: relative address out of range 0x%x\n", rel);
387 		return -ENOEXEC;
388 	}
389 
390 	*location = (*location & 0xffff0000) | (rel & 0xffff);
391 
392 	return 0;
393 }
394 
395 static int apply_r_mips_32(struct module *me, uint32_t *location,
396 			   Elf32_Addr v)
397 {
398 	*location += v;
399 
400 	return 0;
401 }
402 
403 static int apply_r_mips_26(struct module *me, uint32_t *location,
404 			   Elf32_Addr v)
405 {
406 	if (v % 4) {
407 		printk(KERN_DEBUG "VPE loader: apply_r_mips_26 "
408 		       " unaligned relocation\n");
409 		return -ENOEXEC;
410 	}
411 
412 /*
413  * Not desperately convinced this is a good check of an overflow condition
414  * anyway. But it gets in the way of handling undefined weak symbols which
415  * we want to set to zero.
416  * if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
417  * printk(KERN_ERR
418  * "module %s: relocation overflow\n",
419  * me->name);
420  * return -ENOEXEC;
421  * }
422  */
423 
424 	*location = (*location & ~0x03ffffff) |
425 		((*location + (v >> 2)) & 0x03ffffff);
426 	return 0;
427 }
428 
429 static int apply_r_mips_hi16(struct module *me, uint32_t *location,
430 			     Elf32_Addr v)
431 {
432 	struct mips_hi16 *n;
433 
434 	/*
435 	 * We cannot relocate this one now because we don't know the value of
436 	 * the carry we need to add.  Save the information, and let LO16 do the
437 	 * actual relocation.
438 	 */
439 	n = kmalloc(sizeof *n, GFP_KERNEL);
440 	if (!n)
441 		return -ENOMEM;
442 
443 	n->addr = location;
444 	n->value = v;
445 	n->next = mips_hi16_list;
446 	mips_hi16_list = n;
447 
448 	return 0;
449 }
450 
451 static int apply_r_mips_lo16(struct module *me, uint32_t *location,
452 			     Elf32_Addr v)
453 {
454 	unsigned long insnlo = *location;
455 	Elf32_Addr val, vallo;
456 
457 	/* Sign extend the addend we extract from the lo insn.  */
458 	vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
459 
460 	if (mips_hi16_list != NULL) {
461 		struct mips_hi16 *l;
462 
463 		l = mips_hi16_list;
464 		while (l != NULL) {
465 			struct mips_hi16 *next;
466 			unsigned long insn;
467 
468 			/*
469 			 * The value for the HI16 had best be the same.
470 			 */
471  			if (v != l->value) {
472 				printk(KERN_DEBUG "VPE loader: "
473 				       "apply_r_mips_lo16/hi16: 	"
474 				       "inconsistent value information\n");
475 				return -ENOEXEC;
476 			}
477 
478 			/*
479 			 * Do the HI16 relocation.  Note that we actually don't
480 			 * need to know anything about the LO16 itself, except
481 			 * where to find the low 16 bits of the addend needed
482 			 * by the LO16.
483 			 */
484 			insn = *l->addr;
485 			val = ((insn & 0xffff) << 16) + vallo;
486 			val += v;
487 
488 			/*
489 			 * Account for the sign extension that will happen in
490 			 * the low bits.
491 			 */
492 			val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
493 
494 			insn = (insn & ~0xffff) | val;
495 			*l->addr = insn;
496 
497 			next = l->next;
498 			kfree(l);
499 			l = next;
500 		}
501 
502 		mips_hi16_list = NULL;
503 	}
504 
505 	/*
506 	 * Ok, we're done with the HI16 relocs.  Now deal with the LO16.
507 	 */
508 	val = v + vallo;
509 	insnlo = (insnlo & ~0xffff) | (val & 0xffff);
510 	*location = insnlo;
511 
512 	return 0;
513 }
514 
515 static int (*reloc_handlers[]) (struct module *me, uint32_t *location,
516 				Elf32_Addr v) = {
517 	[R_MIPS_NONE]	= apply_r_mips_none,
518 	[R_MIPS_32]	= apply_r_mips_32,
519 	[R_MIPS_26]	= apply_r_mips_26,
520 	[R_MIPS_HI16]	= apply_r_mips_hi16,
521 	[R_MIPS_LO16]	= apply_r_mips_lo16,
522 	[R_MIPS_GPREL16] = apply_r_mips_gprel16,
523 	[R_MIPS_PC16] = apply_r_mips_pc16
524 };
525 
526 static char *rstrs[] = {
527 	[R_MIPS_NONE]	= "MIPS_NONE",
528 	[R_MIPS_32]	= "MIPS_32",
529 	[R_MIPS_26]	= "MIPS_26",
530 	[R_MIPS_HI16]	= "MIPS_HI16",
531 	[R_MIPS_LO16]	= "MIPS_LO16",
532 	[R_MIPS_GPREL16] = "MIPS_GPREL16",
533 	[R_MIPS_PC16] = "MIPS_PC16"
534 };
535 
536 int apply_relocations(Elf32_Shdr *sechdrs,
537 		      const char *strtab,
538 		      unsigned int symindex,
539 		      unsigned int relsec,
540 		      struct module *me)
541 {
542 	Elf32_Rel *rel = (void *) sechdrs[relsec].sh_addr;
543 	Elf32_Sym *sym;
544 	uint32_t *location;
545 	unsigned int i;
546 	Elf32_Addr v;
547 	int res;
548 
549 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
550 		Elf32_Word r_info = rel[i].r_info;
551 
552 		/* This is where to make the change */
553 		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
554 			+ rel[i].r_offset;
555 		/* This is the symbol it is referring to */
556 		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
557 			+ ELF32_R_SYM(r_info);
558 
559 		if (!sym->st_value) {
560 			printk(KERN_DEBUG "%s: undefined weak symbol %s\n",
561 			       me->name, strtab + sym->st_name);
562 			/* just print the warning, dont barf */
563 		}
564 
565 		v = sym->st_value;
566 
567 		res = reloc_handlers[ELF32_R_TYPE(r_info)](me, location, v);
568 		if( res ) {
569 			char *r = rstrs[ELF32_R_TYPE(r_info)];
570 		    	printk(KERN_WARNING "VPE loader: .text+0x%x "
571 			       "relocation type %s for symbol \"%s\" failed\n",
572 			       rel[i].r_offset, r ? r : "UNKNOWN",
573 			       strtab + sym->st_name);
574 			return res;
575 		}
576 	}
577 
578 	return 0;
579 }
580 
581 void save_gp_address(unsigned int secbase, unsigned int rel)
582 {
583 	gp_addr = secbase + rel;
584 	gp_offs = gp_addr - (secbase & 0xffff0000);
585 }
586 /* end module-elf32.c */
587 
588 
589 
590 /* Change all symbols so that sh_value encodes the pointer directly. */
591 static void simplify_symbols(Elf_Shdr * sechdrs,
592 			    unsigned int symindex,
593 			    const char *strtab,
594 			    const char *secstrings,
595 			    unsigned int nsecs, struct module *mod)
596 {
597 	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
598 	unsigned long secbase, bssbase = 0;
599 	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
600 	int size;
601 
602 	/* find the .bss section for COMMON symbols */
603 	for (i = 0; i < nsecs; i++) {
604 		if (strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) == 0) {
605 			bssbase = sechdrs[i].sh_addr;
606 			break;
607 		}
608 	}
609 
610 	for (i = 1; i < n; i++) {
611 		switch (sym[i].st_shndx) {
612 		case SHN_COMMON:
613 			/* Allocate space for the symbol in the .bss section.
614 			   st_value is currently size.
615 			   We want it to have the address of the symbol. */
616 
617 			size = sym[i].st_value;
618 			sym[i].st_value = bssbase;
619 
620 			bssbase += size;
621 			break;
622 
623 		case SHN_ABS:
624 			/* Don't need to do anything */
625 			break;
626 
627 		case SHN_UNDEF:
628 			/* ret = -ENOENT; */
629 			break;
630 
631 		case SHN_MIPS_SCOMMON:
632 			printk(KERN_DEBUG "simplify_symbols: ignoring SHN_MIPS_SCOMMON"
633 			       "symbol <%s> st_shndx %d\n", strtab + sym[i].st_name,
634 			       sym[i].st_shndx);
635 			// .sbss section
636 			break;
637 
638 		default:
639 			secbase = sechdrs[sym[i].st_shndx].sh_addr;
640 
641 			if (strncmp(strtab + sym[i].st_name, "_gp", 3) == 0) {
642 				save_gp_address(secbase, sym[i].st_value);
643 			}
644 
645 			sym[i].st_value += secbase;
646 			break;
647 		}
648 	}
649 }
650 
651 #ifdef DEBUG_ELFLOADER
652 static void dump_elfsymbols(Elf_Shdr * sechdrs, unsigned int symindex,
653 			    const char *strtab, struct module *mod)
654 {
655 	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
656 	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
657 
658 	printk(KERN_DEBUG "dump_elfsymbols: n %d\n", n);
659 	for (i = 1; i < n; i++) {
660 		printk(KERN_DEBUG " i %d name <%s> 0x%x\n", i,
661 		       strtab + sym[i].st_name, sym[i].st_value);
662 	}
663 }
664 #endif
665 
666 /* We are prepared so configure and start the VPE... */
667 static int vpe_run(struct vpe * v)
668 {
669 	unsigned long flags, val, dmt_flag;
670 	struct vpe_notifications *n;
671 	unsigned int vpeflags;
672 	struct tc *t;
673 
674 	/* check we are the Master VPE */
675 	local_irq_save(flags);
676 	val = read_c0_vpeconf0();
677 	if (!(val & VPECONF0_MVP)) {
678 		printk(KERN_WARNING
679 		       "VPE loader: only Master VPE's are allowed to configure MT\n");
680 		local_irq_restore(flags);
681 
682 		return -1;
683 	}
684 
685 	dmt_flag = dmt();
686 	vpeflags = dvpe();
687 
688 	if (!list_empty(&v->tc)) {
689 		if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
690 			evpe(vpeflags);
691 			emt(dmt_flag);
692 			local_irq_restore(flags);
693 
694 			printk(KERN_WARNING
695 			       "VPE loader: TC %d is already in use.\n",
696                                t->index);
697 			return -ENOEXEC;
698 		}
699 	} else {
700 		evpe(vpeflags);
701 		emt(dmt_flag);
702 		local_irq_restore(flags);
703 
704 		printk(KERN_WARNING
705 		       "VPE loader: No TC's associated with VPE %d\n",
706 		       v->minor);
707 
708 		return -ENOEXEC;
709 	}
710 
711 	/* Put MVPE's into 'configuration state' */
712 	set_c0_mvpcontrol(MVPCONTROL_VPC);
713 
714 	settc(t->index);
715 
716 	/* should check it is halted, and not activated */
717 	if ((read_tc_c0_tcstatus() & TCSTATUS_A) || !(read_tc_c0_tchalt() & TCHALT_H)) {
718 		evpe(vpeflags);
719 		emt(dmt_flag);
720 		local_irq_restore(flags);
721 
722 		printk(KERN_WARNING "VPE loader: TC %d is already active!\n",
723 		       t->index);
724 
725 		return -ENOEXEC;
726 	}
727 
728 	/* Write the address we want it to start running from in the TCPC register. */
729 	write_tc_c0_tcrestart((unsigned long)v->__start);
730 	write_tc_c0_tccontext((unsigned long)0);
731 
732 	/*
733 	 * Mark the TC as activated, not interrupt exempt and not dynamically
734 	 * allocatable
735 	 */
736 	val = read_tc_c0_tcstatus();
737 	val = (val & ~(TCSTATUS_DA | TCSTATUS_IXMT)) | TCSTATUS_A;
738 	write_tc_c0_tcstatus(val);
739 
740 	write_tc_c0_tchalt(read_tc_c0_tchalt() & ~TCHALT_H);
741 
742 	/*
743 	 * The sde-kit passes 'memsize' to __start in $a3, so set something
744 	 * here...  Or set $a3 to zero and define DFLT_STACK_SIZE and
745 	 * DFLT_HEAP_SIZE when you compile your program
746 	 */
747 	mttgpr(6, v->ntcs);
748 	mttgpr(7, physical_memsize);
749 
750 	/* set up VPE1 */
751 	/*
752 	 * bind the TC to VPE 1 as late as possible so we only have the final
753 	 * VPE registers to set up, and so an EJTAG probe can trigger on it
754 	 */
755 	write_tc_c0_tcbind((read_tc_c0_tcbind() & ~TCBIND_CURVPE) | 1);
756 
757 	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~(VPECONF0_VPA));
758 
759 	back_to_back_c0_hazard();
760 
761 	/* Set up the XTC bit in vpeconf0 to point at our tc */
762 	write_vpe_c0_vpeconf0( (read_vpe_c0_vpeconf0() & ~(VPECONF0_XTC))
763 	                      | (t->index << VPECONF0_XTC_SHIFT));
764 
765 	back_to_back_c0_hazard();
766 
767 	/* enable this VPE */
768 	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA);
769 
770 	/* clear out any left overs from a previous program */
771 	write_vpe_c0_status(0);
772 	write_vpe_c0_cause(0);
773 
774 	/* take system out of configuration state */
775 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
776 
777 #ifdef CONFIG_SMP
778 	evpe(EVPE_ENABLE);
779 #else
780 	evpe(vpeflags);
781 #endif
782 	emt(dmt_flag);
783 	local_irq_restore(flags);
784 
785 	list_for_each_entry(n, &v->notify, list)
786 		n->start(minor);
787 
788 	return 0;
789 }
790 
791 static int find_vpe_symbols(struct vpe * v, Elf_Shdr * sechdrs,
792 				      unsigned int symindex, const char *strtab,
793 				      struct module *mod)
794 {
795 	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
796 	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
797 
798 	for (i = 1; i < n; i++) {
799 		if (strcmp(strtab + sym[i].st_name, "__start") == 0) {
800 			v->__start = sym[i].st_value;
801 		}
802 
803 		if (strcmp(strtab + sym[i].st_name, "vpe_shared") == 0) {
804 			v->shared_ptr = (void *)sym[i].st_value;
805 		}
806 	}
807 
808 	if ( (v->__start == 0) || (v->shared_ptr == NULL))
809 		return -1;
810 
811 	return 0;
812 }
813 
814 /*
815  * Allocates a VPE with some program code space(the load address), copies the
816  * contents of the program (p)buffer performing relocatations/etc, free's it
817  * when finished.
818  */
819 static int vpe_elfload(struct vpe * v)
820 {
821 	Elf_Ehdr *hdr;
822 	Elf_Shdr *sechdrs;
823 	long err = 0;
824 	char *secstrings, *strtab = NULL;
825 	unsigned int len, i, symindex = 0, strindex = 0, relocate = 0;
826 	struct module mod;	// so we can re-use the relocations code
827 
828 	memset(&mod, 0, sizeof(struct module));
829 	strcpy(mod.name, "VPE loader");
830 
831 	hdr = (Elf_Ehdr *) v->pbuffer;
832 	len = v->plen;
833 
834 	/* Sanity checks against insmoding binaries or wrong arch,
835 	   weird elf version */
836 	if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
837 	    || (hdr->e_type != ET_REL && hdr->e_type != ET_EXEC)
838 	    || !elf_check_arch(hdr)
839 	    || hdr->e_shentsize != sizeof(*sechdrs)) {
840 		printk(KERN_WARNING
841 		       "VPE loader: program wrong arch or weird elf version\n");
842 
843 		return -ENOEXEC;
844 	}
845 
846 	if (hdr->e_type == ET_REL)
847 		relocate = 1;
848 
849 	if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
850 		printk(KERN_ERR "VPE loader: program length %u truncated\n",
851 		       len);
852 
853 		return -ENOEXEC;
854 	}
855 
856 	/* Convenience variables */
857 	sechdrs = (void *)hdr + hdr->e_shoff;
858 	secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
859 	sechdrs[0].sh_addr = 0;
860 
861 	/* And these should exist, but gcc whinges if we don't init them */
862 	symindex = strindex = 0;
863 
864 	if (relocate) {
865 		for (i = 1; i < hdr->e_shnum; i++) {
866 			if (sechdrs[i].sh_type != SHT_NOBITS
867 			    && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) {
868 				printk(KERN_ERR "VPE program length %u truncated\n",
869 				       len);
870 				return -ENOEXEC;
871 			}
872 
873 			/* Mark all sections sh_addr with their address in the
874 			   temporary image. */
875 			sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
876 
877 			/* Internal symbols and strings. */
878 			if (sechdrs[i].sh_type == SHT_SYMTAB) {
879 				symindex = i;
880 				strindex = sechdrs[i].sh_link;
881 				strtab = (char *)hdr + sechdrs[strindex].sh_offset;
882 			}
883 		}
884 		layout_sections(&mod, hdr, sechdrs, secstrings);
885 	}
886 
887 	v->load_addr = alloc_progmem(mod.core_size);
888 	memset(v->load_addr, 0, mod.core_size);
889 
890 	printk("VPE loader: loading to %p\n", v->load_addr);
891 
892 	if (relocate) {
893 		for (i = 0; i < hdr->e_shnum; i++) {
894 			void *dest;
895 
896 			if (!(sechdrs[i].sh_flags & SHF_ALLOC))
897 				continue;
898 
899 			dest = v->load_addr + sechdrs[i].sh_entsize;
900 
901 			if (sechdrs[i].sh_type != SHT_NOBITS)
902 				memcpy(dest, (void *)sechdrs[i].sh_addr,
903 				       sechdrs[i].sh_size);
904 			/* Update sh_addr to point to copy in image. */
905 			sechdrs[i].sh_addr = (unsigned long)dest;
906 
907 			printk(KERN_DEBUG " section sh_name %s sh_addr 0x%x\n",
908 			       secstrings + sechdrs[i].sh_name, sechdrs[i].sh_addr);
909 		}
910 
911  		/* Fix up syms, so that st_value is a pointer to location. */
912  		simplify_symbols(sechdrs, symindex, strtab, secstrings,
913  				 hdr->e_shnum, &mod);
914 
915  		/* Now do relocations. */
916  		for (i = 1; i < hdr->e_shnum; i++) {
917  			const char *strtab = (char *)sechdrs[strindex].sh_addr;
918  			unsigned int info = sechdrs[i].sh_info;
919 
920  			/* Not a valid relocation section? */
921  			if (info >= hdr->e_shnum)
922  				continue;
923 
924  			/* Don't bother with non-allocated sections */
925  			if (!(sechdrs[info].sh_flags & SHF_ALLOC))
926  				continue;
927 
928  			if (sechdrs[i].sh_type == SHT_REL)
929  				err = apply_relocations(sechdrs, strtab, symindex, i,
930  							&mod);
931  			else if (sechdrs[i].sh_type == SHT_RELA)
932  				err = apply_relocate_add(sechdrs, strtab, symindex, i,
933  							 &mod);
934  			if (err < 0)
935  				return err;
936 
937   		}
938   	} else {
939 		struct elf_phdr *phdr = (struct elf_phdr *) ((char *)hdr + hdr->e_phoff);
940 
941 		for (i = 0; i < hdr->e_phnum; i++) {
942 			if (phdr->p_type != PT_LOAD)
943 				continue;
944 
945 			memcpy((void *)phdr->p_vaddr, (char *)hdr + phdr->p_offset, phdr->p_filesz);
946 			memset((void *)phdr->p_vaddr + phdr->p_filesz, 0, phdr->p_memsz - phdr->p_filesz);
947 			phdr++;
948 		}
949 
950 		for (i = 0; i < hdr->e_shnum; i++) {
951  			/* Internal symbols and strings. */
952  			if (sechdrs[i].sh_type == SHT_SYMTAB) {
953  				symindex = i;
954  				strindex = sechdrs[i].sh_link;
955  				strtab = (char *)hdr + sechdrs[strindex].sh_offset;
956 
957  				/* mark the symtab's address for when we try to find the
958  				   magic symbols */
959  				sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
960  			}
961 		}
962 	}
963 
964 	/* make sure it's physically written out */
965 	flush_icache_range((unsigned long)v->load_addr,
966 			   (unsigned long)v->load_addr + v->len);
967 
968 	if ((find_vpe_symbols(v, sechdrs, symindex, strtab, &mod)) < 0) {
969 		if (v->__start == 0) {
970 			printk(KERN_WARNING "VPE loader: program does not contain "
971 			       "a __start symbol\n");
972 			return -ENOEXEC;
973 		}
974 
975 		if (v->shared_ptr == NULL)
976 			printk(KERN_WARNING "VPE loader: "
977 			       "program does not contain vpe_shared symbol.\n"
978 			       " Unable to use AMVP (AP/SP) facilities.\n");
979 	}
980 
981 	printk(" elf loaded\n");
982 	return 0;
983 }
984 
985 static void cleanup_tc(struct tc *tc)
986 {
987 	unsigned long flags;
988 	unsigned int mtflags, vpflags;
989 	int tmp;
990 
991 	local_irq_save(flags);
992 	mtflags = dmt();
993 	vpflags = dvpe();
994 	/* Put MVPE's into 'configuration state' */
995 	set_c0_mvpcontrol(MVPCONTROL_VPC);
996 
997 	settc(tc->index);
998 	tmp = read_tc_c0_tcstatus();
999 
1000 	/* mark not allocated and not dynamically allocatable */
1001 	tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1002 	tmp |= TCSTATUS_IXMT;	/* interrupt exempt */
1003 	write_tc_c0_tcstatus(tmp);
1004 
1005 	write_tc_c0_tchalt(TCHALT_H);
1006 
1007 	/* bind it to anything other than VPE1 */
1008 //	write_tc_c0_tcbind(read_tc_c0_tcbind() & ~TCBIND_CURVPE); // | TCBIND_CURVPE
1009 
1010 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1011 	evpe(vpflags);
1012 	emt(mtflags);
1013 	local_irq_restore(flags);
1014 }
1015 
1016 static int getcwd(char *buff, int size)
1017 {
1018 	mm_segment_t old_fs;
1019 	int ret;
1020 
1021 	old_fs = get_fs();
1022 	set_fs(KERNEL_DS);
1023 
1024 	ret = sys_getcwd(buff, size);
1025 
1026 	set_fs(old_fs);
1027 
1028 	return ret;
1029 }
1030 
1031 /* checks VPE is unused and gets ready to load program  */
1032 static int vpe_open(struct inode *inode, struct file *filp)
1033 {
1034 	enum vpe_state state;
1035 	struct vpe_notifications *not;
1036 	struct vpe *v;
1037 	int ret;
1038 
1039 	if (minor != iminor(inode)) {
1040 		/* assume only 1 device at the moment. */
1041 		printk(KERN_WARNING "VPE loader: only vpe1 is supported\n");
1042 		return -ENODEV;
1043 	}
1044 
1045 	if ((v = get_vpe(tclimit)) == NULL) {
1046 		printk(KERN_WARNING "VPE loader: unable to get vpe\n");
1047 		return -ENODEV;
1048 	}
1049 
1050 	state = xchg(&v->state, VPE_STATE_INUSE);
1051 	if (state != VPE_STATE_UNUSED) {
1052 		printk(KERN_DEBUG "VPE loader: tc in use dumping regs\n");
1053 
1054 		list_for_each_entry(not, &v->notify, list) {
1055 			not->stop(tclimit);
1056 		}
1057 
1058 		release_progmem(v->load_addr);
1059 		cleanup_tc(get_tc(tclimit));
1060 	}
1061 
1062 	/* this of-course trashes what was there before... */
1063 	v->pbuffer = vmalloc(P_SIZE);
1064 	v->plen = P_SIZE;
1065 	v->load_addr = NULL;
1066 	v->len = 0;
1067 
1068 	v->uid = filp->f_uid;
1069 	v->gid = filp->f_gid;
1070 
1071 #ifdef CONFIG_MIPS_APSP_KSPD
1072 	/* get kspd to tell us when a syscall_exit happens */
1073 	if (!kspd_events_reqd) {
1074 		kspd_notify(&kspd_events);
1075 		kspd_events_reqd++;
1076 	}
1077 #endif
1078 
1079 	v->cwd[0] = 0;
1080 	ret = getcwd(v->cwd, VPE_PATH_MAX);
1081 	if (ret < 0)
1082 		printk(KERN_WARNING "VPE loader: open, getcwd returned %d\n", ret);
1083 
1084 	v->shared_ptr = NULL;
1085 	v->__start = 0;
1086 
1087 	return 0;
1088 }
1089 
1090 static int vpe_release(struct inode *inode, struct file *filp)
1091 {
1092 	struct vpe *v;
1093 	Elf_Ehdr *hdr;
1094 	int ret = 0;
1095 
1096 	v = get_vpe(tclimit);
1097 	if (v == NULL)
1098 		return -ENODEV;
1099 
1100 	hdr = (Elf_Ehdr *) v->pbuffer;
1101 	if (memcmp(hdr->e_ident, ELFMAG, 4) == 0) {
1102 		if (vpe_elfload(v) >= 0) {
1103 			vpe_run(v);
1104 		} else {
1105  			printk(KERN_WARNING "VPE loader: ELF load failed.\n");
1106 			ret = -ENOEXEC;
1107 		}
1108 	} else {
1109  		printk(KERN_WARNING "VPE loader: only elf files are supported\n");
1110 		ret = -ENOEXEC;
1111 	}
1112 
1113 	/* It's good to be able to run the SP and if it chokes have a look at
1114 	   the /dev/rt?. But if we reset the pointer to the shared struct we
1115 	   loose what has happened. So perhaps if garbage is sent to the vpe
1116 	   device, use it as a trigger for the reset. Hopefully a nice
1117 	   executable will be along shortly. */
1118 	if (ret < 0)
1119 		v->shared_ptr = NULL;
1120 
1121 	// cleanup any temp buffers
1122 	if (v->pbuffer)
1123 		vfree(v->pbuffer);
1124 	v->plen = 0;
1125 	return ret;
1126 }
1127 
1128 static ssize_t vpe_write(struct file *file, const char __user * buffer,
1129 			 size_t count, loff_t * ppos)
1130 {
1131 	size_t ret = count;
1132 	struct vpe *v;
1133 
1134 	if (iminor(file->f_path.dentry->d_inode) != minor)
1135 		return -ENODEV;
1136 
1137 	v = get_vpe(tclimit);
1138 	if (v == NULL)
1139 		return -ENODEV;
1140 
1141 	if (v->pbuffer == NULL) {
1142 		printk(KERN_ERR "VPE loader: no buffer for program\n");
1143 		return -ENOMEM;
1144 	}
1145 
1146 	if ((count + v->len) > v->plen) {
1147 		printk(KERN_WARNING
1148 		       "VPE loader: elf size too big. Perhaps strip uneeded symbols\n");
1149 		return -ENOMEM;
1150 	}
1151 
1152 	count -= copy_from_user(v->pbuffer + v->len, buffer, count);
1153 	if (!count)
1154 		return -EFAULT;
1155 
1156 	v->len += count;
1157 	return ret;
1158 }
1159 
1160 static const struct file_operations vpe_fops = {
1161 	.owner = THIS_MODULE,
1162 	.open = vpe_open,
1163 	.release = vpe_release,
1164 	.write = vpe_write
1165 };
1166 
1167 /* module wrapper entry points */
1168 /* give me a vpe */
1169 vpe_handle vpe_alloc(void)
1170 {
1171 	int i;
1172 	struct vpe *v;
1173 
1174 	/* find a vpe */
1175 	for (i = 1; i < MAX_VPES; i++) {
1176 		if ((v = get_vpe(i)) != NULL) {
1177 			v->state = VPE_STATE_INUSE;
1178 			return v;
1179 		}
1180 	}
1181 	return NULL;
1182 }
1183 
1184 EXPORT_SYMBOL(vpe_alloc);
1185 
1186 /* start running from here */
1187 int vpe_start(vpe_handle vpe, unsigned long start)
1188 {
1189 	struct vpe *v = vpe;
1190 
1191 	v->__start = start;
1192 	return vpe_run(v);
1193 }
1194 
1195 EXPORT_SYMBOL(vpe_start);
1196 
1197 /* halt it for now */
1198 int vpe_stop(vpe_handle vpe)
1199 {
1200 	struct vpe *v = vpe;
1201 	struct tc *t;
1202 	unsigned int evpe_flags;
1203 
1204 	evpe_flags = dvpe();
1205 
1206 	if ((t = list_entry(v->tc.next, struct tc, tc)) != NULL) {
1207 
1208 		settc(t->index);
1209 		write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1210 	}
1211 
1212 	evpe(evpe_flags);
1213 
1214 	return 0;
1215 }
1216 
1217 EXPORT_SYMBOL(vpe_stop);
1218 
1219 /* I've done with it thank you */
1220 int vpe_free(vpe_handle vpe)
1221 {
1222 	struct vpe *v = vpe;
1223 	struct tc *t;
1224 	unsigned int evpe_flags;
1225 
1226 	if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
1227 		return -ENOEXEC;
1228 	}
1229 
1230 	evpe_flags = dvpe();
1231 
1232 	/* Put MVPE's into 'configuration state' */
1233 	set_c0_mvpcontrol(MVPCONTROL_VPC);
1234 
1235 	settc(t->index);
1236 	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1237 
1238 	/* mark the TC unallocated and halt'ed */
1239 	write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A);
1240 	write_tc_c0_tchalt(TCHALT_H);
1241 
1242 	v->state = VPE_STATE_UNUSED;
1243 
1244 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1245 	evpe(evpe_flags);
1246 
1247 	return 0;
1248 }
1249 
1250 EXPORT_SYMBOL(vpe_free);
1251 
1252 void *vpe_get_shared(int index)
1253 {
1254 	struct vpe *v;
1255 
1256 	if ((v = get_vpe(index)) == NULL)
1257 		return NULL;
1258 
1259 	return v->shared_ptr;
1260 }
1261 
1262 EXPORT_SYMBOL(vpe_get_shared);
1263 
1264 int vpe_getuid(int index)
1265 {
1266 	struct vpe *v;
1267 
1268 	if ((v = get_vpe(index)) == NULL)
1269 		return -1;
1270 
1271 	return v->uid;
1272 }
1273 
1274 EXPORT_SYMBOL(vpe_getuid);
1275 
1276 int vpe_getgid(int index)
1277 {
1278 	struct vpe *v;
1279 
1280 	if ((v = get_vpe(index)) == NULL)
1281 		return -1;
1282 
1283 	return v->gid;
1284 }
1285 
1286 EXPORT_SYMBOL(vpe_getgid);
1287 
1288 int vpe_notify(int index, struct vpe_notifications *notify)
1289 {
1290 	struct vpe *v;
1291 
1292 	if ((v = get_vpe(index)) == NULL)
1293 		return -1;
1294 
1295 	list_add(&notify->list, &v->notify);
1296 	return 0;
1297 }
1298 
1299 EXPORT_SYMBOL(vpe_notify);
1300 
1301 char *vpe_getcwd(int index)
1302 {
1303 	struct vpe *v;
1304 
1305 	if ((v = get_vpe(index)) == NULL)
1306 		return NULL;
1307 
1308 	return v->cwd;
1309 }
1310 
1311 EXPORT_SYMBOL(vpe_getcwd);
1312 
1313 #ifdef CONFIG_MIPS_APSP_KSPD
1314 static void kspd_sp_exit( int sp_id)
1315 {
1316 	cleanup_tc(get_tc(sp_id));
1317 }
1318 #endif
1319 
1320 static ssize_t store_kill(struct class_device *dev, const char *buf, size_t len)
1321 {
1322 	struct vpe *vpe = get_vpe(tclimit);
1323 	struct vpe_notifications *not;
1324 
1325 	list_for_each_entry(not, &vpe->notify, list) {
1326 		not->stop(tclimit);
1327 	}
1328 
1329 	release_progmem(vpe->load_addr);
1330 	cleanup_tc(get_tc(tclimit));
1331 	vpe_stop(vpe);
1332 	vpe_free(vpe);
1333 
1334 	return len;
1335 }
1336 
1337 static ssize_t show_ntcs(struct class_device *cd, char *buf)
1338 {
1339 	struct vpe *vpe = get_vpe(tclimit);
1340 
1341 	return sprintf(buf, "%d\n", vpe->ntcs);
1342 }
1343 
1344 static ssize_t store_ntcs(struct class_device *dev, const char *buf, size_t len)
1345 {
1346 	struct vpe *vpe = get_vpe(tclimit);
1347 	unsigned long new;
1348 	char *endp;
1349 
1350 	new = simple_strtoul(buf, &endp, 0);
1351 	if (endp == buf)
1352 		goto out_einval;
1353 
1354 	if (new == 0 || new > (hw_tcs - tclimit))
1355 		goto out_einval;
1356 
1357 	vpe->ntcs = new;
1358 
1359 	return len;
1360 
1361 out_einval:
1362 	return -EINVAL;;
1363 }
1364 
1365 static struct class_device_attribute vpe_class_attributes[] = {
1366 	__ATTR(kill, S_IWUSR, NULL, store_kill),
1367 	__ATTR(ntcs, S_IRUGO | S_IWUSR, show_ntcs, store_ntcs),
1368 	{}
1369 };
1370 
1371 static void vpe_class_device_release(struct class_device *cd)
1372 {
1373 	kfree(cd);
1374 }
1375 
1376 struct class vpe_class = {
1377 	.name = "vpe",
1378 	.owner = THIS_MODULE,
1379 	.release = vpe_class_device_release,
1380 	.class_dev_attrs = vpe_class_attributes,
1381 };
1382 
1383 struct class_device vpe_device;
1384 
1385 static int __init vpe_module_init(void)
1386 {
1387 	unsigned int mtflags, vpflags;
1388 	unsigned long flags, val;
1389 	struct vpe *v = NULL;
1390 	struct tc *t;
1391 	int tc, err;
1392 
1393 	if (!cpu_has_mipsmt) {
1394 		printk("VPE loader: not a MIPS MT capable processor\n");
1395 		return -ENODEV;
1396 	}
1397 
1398 	if (vpelimit == 0) {
1399 		printk(KERN_WARNING "No VPEs reserved for AP/SP, not "
1400 		       "initializing VPE loader.\nPass maxvpes=<n> argument as "
1401 		       "kernel argument\n");
1402 
1403 		return -ENODEV;
1404 	}
1405 
1406 	if (tclimit == 0) {
1407 		printk(KERN_WARNING "No TCs reserved for AP/SP, not "
1408 		       "initializing VPE loader.\nPass maxtcs=<n> argument as "
1409 		       "kernel argument\n");
1410 
1411 		return -ENODEV;
1412 	}
1413 
1414 	major = register_chrdev(0, module_name, &vpe_fops);
1415 	if (major < 0) {
1416 		printk("VPE loader: unable to register character device\n");
1417 		return major;
1418 	}
1419 
1420 	err = class_register(&vpe_class);
1421 	if (err) {
1422 		printk(KERN_ERR "vpe_class registration failed\n");
1423 		goto out_chrdev;
1424 	}
1425 
1426 	class_device_initialize(&vpe_device);
1427 	vpe_device.class	= &vpe_class,
1428 	vpe_device.parent	= NULL,
1429 	strlcpy(vpe_device.class_id, "vpe1", BUS_ID_SIZE);
1430 	vpe_device.devt = MKDEV(major, minor);
1431 	err = class_device_add(&vpe_device);
1432 	if (err) {
1433 		printk(KERN_ERR "Adding vpe_device failed\n");
1434 		goto out_class;
1435 	}
1436 
1437 	local_irq_save(flags);
1438 	mtflags = dmt();
1439 	vpflags = dvpe();
1440 
1441 	/* Put MVPE's into 'configuration state' */
1442 	set_c0_mvpcontrol(MVPCONTROL_VPC);
1443 
1444 	/* dump_mtregs(); */
1445 
1446 	val = read_c0_mvpconf0();
1447 	hw_tcs = (val & MVPCONF0_PTC) + 1;
1448 	hw_vpes = ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
1449 
1450 	for (tc = tclimit; tc < hw_tcs; tc++) {
1451 		/*
1452 		 * Must re-enable multithreading temporarily or in case we
1453 		 * reschedule send IPIs or similar we might hang.
1454 		 */
1455 		clear_c0_mvpcontrol(MVPCONTROL_VPC);
1456 		evpe(vpflags);
1457 		emt(mtflags);
1458 		local_irq_restore(flags);
1459 		t = alloc_tc(tc);
1460 		if (!t) {
1461 			err = -ENOMEM;
1462 			goto out;
1463 		}
1464 
1465 		local_irq_save(flags);
1466 		mtflags = dmt();
1467 		vpflags = dvpe();
1468 		set_c0_mvpcontrol(MVPCONTROL_VPC);
1469 
1470 		/* VPE's */
1471 		if (tc < hw_tcs) {
1472 			settc(tc);
1473 
1474 			if ((v = alloc_vpe(tc)) == NULL) {
1475 				printk(KERN_WARNING "VPE: unable to allocate VPE\n");
1476 
1477 				goto out_reenable;
1478 			}
1479 
1480 			v->ntcs = hw_tcs - tclimit;
1481 
1482 			/* add the tc to the list of this vpe's tc's. */
1483 			list_add(&t->tc, &v->tc);
1484 
1485 			/* deactivate all but vpe0 */
1486 			if (tc >= tclimit) {
1487 				unsigned long tmp = read_vpe_c0_vpeconf0();
1488 
1489 				tmp &= ~VPECONF0_VPA;
1490 
1491 				/* master VPE */
1492 				tmp |= VPECONF0_MVP;
1493 				write_vpe_c0_vpeconf0(tmp);
1494 			}
1495 
1496 			/* disable multi-threading with TC's */
1497 			write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE);
1498 
1499 			if (tc >= vpelimit) {
1500 				/*
1501 				 * Set config to be the same as vpe0,
1502 				 * particularly kseg0 coherency alg
1503 				 */
1504 				write_vpe_c0_config(read_c0_config());
1505 			}
1506 		}
1507 
1508 		/* TC's */
1509 		t->pvpe = v;	/* set the parent vpe */
1510 
1511 		if (tc >= tclimit) {
1512 			unsigned long tmp;
1513 
1514 			settc(tc);
1515 
1516 			/* Any TC that is bound to VPE0 gets left as is - in case
1517 			   we are running SMTC on VPE0. A TC that is bound to any
1518 			   other VPE gets bound to VPE0, ideally I'd like to make
1519 			   it homeless but it doesn't appear to let me bind a TC
1520 			   to a non-existent VPE. Which is perfectly reasonable.
1521 
1522 			   The (un)bound state is visible to an EJTAG probe so may
1523 			   notify GDB...
1524 			*/
1525 
1526 			if (((tmp = read_tc_c0_tcbind()) & TCBIND_CURVPE)) {
1527 				/* tc is bound >vpe0 */
1528 				write_tc_c0_tcbind(tmp & ~TCBIND_CURVPE);
1529 
1530 				t->pvpe = get_vpe(0);	/* set the parent vpe */
1531 			}
1532 
1533 			tmp = read_tc_c0_tcstatus();
1534 
1535 			/* mark not activated and not dynamically allocatable */
1536 			tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1537 			tmp |= TCSTATUS_IXMT;	/* interrupt exempt */
1538 			write_tc_c0_tcstatus(tmp);
1539 
1540 			write_tc_c0_tchalt(TCHALT_H);
1541 		}
1542 	}
1543 
1544 out_reenable:
1545 	/* release config state */
1546 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1547 
1548 	evpe(vpflags);
1549 	emt(mtflags);
1550 	local_irq_restore(flags);
1551 
1552 #ifdef CONFIG_MIPS_APSP_KSPD
1553 	kspd_events.kspd_sp_exit = kspd_sp_exit;
1554 #endif
1555 	return 0;
1556 
1557 out_class:
1558 	class_unregister(&vpe_class);
1559 out_chrdev:
1560 	unregister_chrdev(major, module_name);
1561 
1562 out:
1563 	return err;
1564 }
1565 
1566 static void __exit vpe_module_exit(void)
1567 {
1568 	struct vpe *v, *n;
1569 
1570 	list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list) {
1571 		if (v->state != VPE_STATE_UNUSED) {
1572 			release_vpe(v);
1573 		}
1574 	}
1575 
1576 	class_device_del(&vpe_device);
1577 	unregister_chrdev(major, module_name);
1578 }
1579 
1580 module_init(vpe_module_init);
1581 module_exit(vpe_module_exit);
1582 MODULE_DESCRIPTION("MIPS VPE Loader");
1583 MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
1584 MODULE_LICENSE("GPL");
1585