xref: /openbmc/linux/arch/mips/kernel/vpe.c (revision fd589a8f)
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/smp_lock.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 
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;
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 
159 /* get the vpe associated with this minor */
160 static 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 static 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 /* allocate a vpe and associate it with this minor (or index) */
189 static struct vpe *alloc_vpe(int minor)
190 {
191 	struct vpe *v;
192 
193 	if ((v = kzalloc(sizeof(struct vpe), GFP_KERNEL)) == NULL) {
194 		return NULL;
195 	}
196 
197 	INIT_LIST_HEAD(&v->tc);
198 	list_add_tail(&v->list, &vpecontrol.vpe_list);
199 
200 	INIT_LIST_HEAD(&v->notify);
201 	v->minor = minor;
202 	return v;
203 }
204 
205 /* allocate a tc. At startup only tc0 is running, all other can be halted. */
206 static struct tc *alloc_tc(int index)
207 {
208 	struct tc *tc;
209 
210 	if ((tc = kzalloc(sizeof(struct tc), GFP_KERNEL)) == NULL)
211 		goto out;
212 
213 	INIT_LIST_HEAD(&tc->tc);
214 	tc->index = index;
215 	list_add_tail(&tc->list, &vpecontrol.tc_list);
216 
217 out:
218 	return tc;
219 }
220 
221 /* clean up and free everything */
222 static void release_vpe(struct vpe *v)
223 {
224 	list_del(&v->list);
225 	if (v->load_addr)
226 		release_progmem(v);
227 	kfree(v);
228 }
229 
230 static void dump_mtregs(void)
231 {
232 	unsigned long val;
233 
234 	val = read_c0_config3();
235 	printk("config3 0x%lx MT %ld\n", val,
236 	       (val & CONFIG3_MT) >> CONFIG3_MT_SHIFT);
237 
238 	val = read_c0_mvpcontrol();
239 	printk("MVPControl 0x%lx, STLB %ld VPC %ld EVP %ld\n", val,
240 	       (val & MVPCONTROL_STLB) >> MVPCONTROL_STLB_SHIFT,
241 	       (val & MVPCONTROL_VPC) >> MVPCONTROL_VPC_SHIFT,
242 	       (val & MVPCONTROL_EVP));
243 
244 	val = read_c0_mvpconf0();
245 	printk("mvpconf0 0x%lx, PVPE %ld PTC %ld M %ld\n", val,
246 	       (val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT,
247 	       val & MVPCONF0_PTC, (val & MVPCONF0_M) >> MVPCONF0_M_SHIFT);
248 }
249 
250 /* Find some VPE program space  */
251 static void *alloc_progmem(unsigned long len)
252 {
253 	void *addr;
254 
255 #ifdef CONFIG_MIPS_VPE_LOADER_TOM
256 	/*
257 	 * This means you must tell Linux to use less memory than you
258 	 * physically have, for example by passing a mem= boot argument.
259 	 */
260 	addr = pfn_to_kaddr(max_low_pfn);
261 	memset(addr, 0, len);
262 #else
263 	/* simple grab some mem for now */
264 	addr = kzalloc(len, GFP_KERNEL);
265 #endif
266 
267 	return addr;
268 }
269 
270 static void release_progmem(void *ptr)
271 {
272 #ifndef CONFIG_MIPS_VPE_LOADER_TOM
273 	kfree(ptr);
274 #endif
275 }
276 
277 /* Update size with this section: return offset. */
278 static long get_offset(unsigned long *size, Elf_Shdr * sechdr)
279 {
280 	long ret;
281 
282 	ret = ALIGN(*size, sechdr->sh_addralign ? : 1);
283 	*size = ret + sechdr->sh_size;
284 	return ret;
285 }
286 
287 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
288    might -- code, read-only data, read-write data, small data.  Tally
289    sizes, and place the offsets into sh_entsize fields: high bit means it
290    belongs in init. */
291 static void layout_sections(struct module *mod, const Elf_Ehdr * hdr,
292 			    Elf_Shdr * sechdrs, const char *secstrings)
293 {
294 	static unsigned long const masks[][2] = {
295 		/* NOTE: all executable code must be the first section
296 		 * in this array; otherwise modify the text_size
297 		 * finder in the two loops below */
298 		{SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL},
299 		{SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL},
300 		{SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL},
301 		{ARCH_SHF_SMALL | SHF_ALLOC, 0}
302 	};
303 	unsigned int m, i;
304 
305 	for (i = 0; i < hdr->e_shnum; i++)
306 		sechdrs[i].sh_entsize = ~0UL;
307 
308 	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
309 		for (i = 0; i < hdr->e_shnum; ++i) {
310 			Elf_Shdr *s = &sechdrs[i];
311 
312 			//  || strncmp(secstrings + s->sh_name, ".init", 5) == 0)
313 			if ((s->sh_flags & masks[m][0]) != masks[m][0]
314 			    || (s->sh_flags & masks[m][1])
315 			    || s->sh_entsize != ~0UL)
316 				continue;
317 			s->sh_entsize =
318 				get_offset((unsigned long *)&mod->core_size, s);
319 		}
320 
321 		if (m == 0)
322 			mod->core_text_size = mod->core_size;
323 
324 	}
325 }
326 
327 
328 /* from module-elf32.c, but subverted a little */
329 
330 struct mips_hi16 {
331 	struct mips_hi16 *next;
332 	Elf32_Addr *addr;
333 	Elf32_Addr value;
334 };
335 
336 static struct mips_hi16 *mips_hi16_list;
337 static unsigned int gp_offs, gp_addr;
338 
339 static int apply_r_mips_none(struct module *me, uint32_t *location,
340 			     Elf32_Addr v)
341 {
342 	return 0;
343 }
344 
345 static int apply_r_mips_gprel16(struct module *me, uint32_t *location,
346 				Elf32_Addr v)
347 {
348 	int rel;
349 
350 	if( !(*location & 0xffff) ) {
351 		rel = (int)v - gp_addr;
352 	}
353 	else {
354 		/* .sbss + gp(relative) + offset */
355 		/* kludge! */
356 		rel =  (int)(short)((int)v + gp_offs +
357 				    (int)(short)(*location & 0xffff) - gp_addr);
358 	}
359 
360 	if( (rel > 32768) || (rel < -32768) ) {
361 		printk(KERN_DEBUG "VPE loader: apply_r_mips_gprel16: "
362 		       "relative address 0x%x out of range of gp register\n",
363 		       rel);
364 		return -ENOEXEC;
365 	}
366 
367 	*location = (*location & 0xffff0000) | (rel & 0xffff);
368 
369 	return 0;
370 }
371 
372 static int apply_r_mips_pc16(struct module *me, uint32_t *location,
373 			     Elf32_Addr v)
374 {
375 	int rel;
376 	rel = (((unsigned int)v - (unsigned int)location));
377 	rel >>= 2;		// because the offset is in _instructions_ not bytes.
378 	rel -= 1;		// and one instruction less due to the branch delay slot.
379 
380 	if( (rel > 32768) || (rel < -32768) ) {
381 		printk(KERN_DEBUG "VPE loader: "
382  		       "apply_r_mips_pc16: relative address out of range 0x%x\n", rel);
383 		return -ENOEXEC;
384 	}
385 
386 	*location = (*location & 0xffff0000) | (rel & 0xffff);
387 
388 	return 0;
389 }
390 
391 static int apply_r_mips_32(struct module *me, uint32_t *location,
392 			   Elf32_Addr v)
393 {
394 	*location += v;
395 
396 	return 0;
397 }
398 
399 static int apply_r_mips_26(struct module *me, uint32_t *location,
400 			   Elf32_Addr v)
401 {
402 	if (v % 4) {
403 		printk(KERN_DEBUG "VPE loader: apply_r_mips_26 "
404 		       " unaligned relocation\n");
405 		return -ENOEXEC;
406 	}
407 
408 /*
409  * Not desperately convinced this is a good check of an overflow condition
410  * anyway. But it gets in the way of handling undefined weak symbols which
411  * we want to set to zero.
412  * if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
413  * printk(KERN_ERR
414  * "module %s: relocation overflow\n",
415  * me->name);
416  * return -ENOEXEC;
417  * }
418  */
419 
420 	*location = (*location & ~0x03ffffff) |
421 		((*location + (v >> 2)) & 0x03ffffff);
422 	return 0;
423 }
424 
425 static int apply_r_mips_hi16(struct module *me, uint32_t *location,
426 			     Elf32_Addr v)
427 {
428 	struct mips_hi16 *n;
429 
430 	/*
431 	 * We cannot relocate this one now because we don't know the value of
432 	 * the carry we need to add.  Save the information, and let LO16 do the
433 	 * actual relocation.
434 	 */
435 	n = kmalloc(sizeof *n, GFP_KERNEL);
436 	if (!n)
437 		return -ENOMEM;
438 
439 	n->addr = location;
440 	n->value = v;
441 	n->next = mips_hi16_list;
442 	mips_hi16_list = n;
443 
444 	return 0;
445 }
446 
447 static int apply_r_mips_lo16(struct module *me, uint32_t *location,
448 			     Elf32_Addr v)
449 {
450 	unsigned long insnlo = *location;
451 	Elf32_Addr val, vallo;
452 	struct mips_hi16 *l, *next;
453 
454 	/* Sign extend the addend we extract from the lo insn.  */
455 	vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
456 
457 	if (mips_hi16_list != NULL) {
458 
459 		l = mips_hi16_list;
460 		while (l != NULL) {
461 			unsigned long insn;
462 
463 			/*
464 			 * The value for the HI16 had best be the same.
465 			 */
466  			if (v != l->value) {
467 				printk(KERN_DEBUG "VPE loader: "
468 				       "apply_r_mips_lo16/hi16: \t"
469 				       "inconsistent value information\n");
470 				goto out_free;
471 			}
472 
473 			/*
474 			 * Do the HI16 relocation.  Note that we actually don't
475 			 * need to know anything about the LO16 itself, except
476 			 * where to find the low 16 bits of the addend needed
477 			 * by the LO16.
478 			 */
479 			insn = *l->addr;
480 			val = ((insn & 0xffff) << 16) + vallo;
481 			val += v;
482 
483 			/*
484 			 * Account for the sign extension that will happen in
485 			 * the low bits.
486 			 */
487 			val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
488 
489 			insn = (insn & ~0xffff) | val;
490 			*l->addr = insn;
491 
492 			next = l->next;
493 			kfree(l);
494 			l = next;
495 		}
496 
497 		mips_hi16_list = NULL;
498 	}
499 
500 	/*
501 	 * Ok, we're done with the HI16 relocs.  Now deal with the LO16.
502 	 */
503 	val = v + vallo;
504 	insnlo = (insnlo & ~0xffff) | (val & 0xffff);
505 	*location = insnlo;
506 
507 	return 0;
508 
509 out_free:
510 	while (l != NULL) {
511 		next = l->next;
512 		kfree(l);
513 		l = next;
514 	}
515 	mips_hi16_list = NULL;
516 
517 	return -ENOEXEC;
518 }
519 
520 static int (*reloc_handlers[]) (struct module *me, uint32_t *location,
521 				Elf32_Addr v) = {
522 	[R_MIPS_NONE]	= apply_r_mips_none,
523 	[R_MIPS_32]	= apply_r_mips_32,
524 	[R_MIPS_26]	= apply_r_mips_26,
525 	[R_MIPS_HI16]	= apply_r_mips_hi16,
526 	[R_MIPS_LO16]	= apply_r_mips_lo16,
527 	[R_MIPS_GPREL16] = apply_r_mips_gprel16,
528 	[R_MIPS_PC16] = apply_r_mips_pc16
529 };
530 
531 static char *rstrs[] = {
532 	[R_MIPS_NONE]	= "MIPS_NONE",
533 	[R_MIPS_32]	= "MIPS_32",
534 	[R_MIPS_26]	= "MIPS_26",
535 	[R_MIPS_HI16]	= "MIPS_HI16",
536 	[R_MIPS_LO16]	= "MIPS_LO16",
537 	[R_MIPS_GPREL16] = "MIPS_GPREL16",
538 	[R_MIPS_PC16] = "MIPS_PC16"
539 };
540 
541 static int apply_relocations(Elf32_Shdr *sechdrs,
542 		      const char *strtab,
543 		      unsigned int symindex,
544 		      unsigned int relsec,
545 		      struct module *me)
546 {
547 	Elf32_Rel *rel = (void *) sechdrs[relsec].sh_addr;
548 	Elf32_Sym *sym;
549 	uint32_t *location;
550 	unsigned int i;
551 	Elf32_Addr v;
552 	int res;
553 
554 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
555 		Elf32_Word r_info = rel[i].r_info;
556 
557 		/* This is where to make the change */
558 		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
559 			+ rel[i].r_offset;
560 		/* This is the symbol it is referring to */
561 		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
562 			+ ELF32_R_SYM(r_info);
563 
564 		if (!sym->st_value) {
565 			printk(KERN_DEBUG "%s: undefined weak symbol %s\n",
566 			       me->name, strtab + sym->st_name);
567 			/* just print the warning, dont barf */
568 		}
569 
570 		v = sym->st_value;
571 
572 		res = reloc_handlers[ELF32_R_TYPE(r_info)](me, location, v);
573 		if( res ) {
574 			char *r = rstrs[ELF32_R_TYPE(r_info)];
575 		    	printk(KERN_WARNING "VPE loader: .text+0x%x "
576 			       "relocation type %s for symbol \"%s\" failed\n",
577 			       rel[i].r_offset, r ? r : "UNKNOWN",
578 			       strtab + sym->st_name);
579 			return res;
580 		}
581 	}
582 
583 	return 0;
584 }
585 
586 static inline void save_gp_address(unsigned int secbase, unsigned int rel)
587 {
588 	gp_addr = secbase + rel;
589 	gp_offs = gp_addr - (secbase & 0xffff0000);
590 }
591 /* end module-elf32.c */
592 
593 
594 
595 /* Change all symbols so that sh_value encodes the pointer directly. */
596 static void simplify_symbols(Elf_Shdr * sechdrs,
597 			    unsigned int symindex,
598 			    const char *strtab,
599 			    const char *secstrings,
600 			    unsigned int nsecs, struct module *mod)
601 {
602 	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
603 	unsigned long secbase, bssbase = 0;
604 	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
605 	int size;
606 
607 	/* find the .bss section for COMMON symbols */
608 	for (i = 0; i < nsecs; i++) {
609 		if (strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) == 0) {
610 			bssbase = sechdrs[i].sh_addr;
611 			break;
612 		}
613 	}
614 
615 	for (i = 1; i < n; i++) {
616 		switch (sym[i].st_shndx) {
617 		case SHN_COMMON:
618 			/* Allocate space for the symbol in the .bss section.
619 			   st_value is currently size.
620 			   We want it to have the address of the symbol. */
621 
622 			size = sym[i].st_value;
623 			sym[i].st_value = bssbase;
624 
625 			bssbase += size;
626 			break;
627 
628 		case SHN_ABS:
629 			/* Don't need to do anything */
630 			break;
631 
632 		case SHN_UNDEF:
633 			/* ret = -ENOENT; */
634 			break;
635 
636 		case SHN_MIPS_SCOMMON:
637 			printk(KERN_DEBUG "simplify_symbols: ignoring SHN_MIPS_SCOMMON "
638 			       "symbol <%s> st_shndx %d\n", strtab + sym[i].st_name,
639 			       sym[i].st_shndx);
640 			// .sbss section
641 			break;
642 
643 		default:
644 			secbase = sechdrs[sym[i].st_shndx].sh_addr;
645 
646 			if (strncmp(strtab + sym[i].st_name, "_gp", 3) == 0) {
647 				save_gp_address(secbase, sym[i].st_value);
648 			}
649 
650 			sym[i].st_value += secbase;
651 			break;
652 		}
653 	}
654 }
655 
656 #ifdef DEBUG_ELFLOADER
657 static void dump_elfsymbols(Elf_Shdr * sechdrs, unsigned int symindex,
658 			    const char *strtab, struct module *mod)
659 {
660 	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
661 	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
662 
663 	printk(KERN_DEBUG "dump_elfsymbols: n %d\n", n);
664 	for (i = 1; i < n; i++) {
665 		printk(KERN_DEBUG " i %d name <%s> 0x%x\n", i,
666 		       strtab + sym[i].st_name, sym[i].st_value);
667 	}
668 }
669 #endif
670 
671 /* We are prepared so configure and start the VPE... */
672 static int vpe_run(struct vpe * v)
673 {
674 	unsigned long flags, val, dmt_flag;
675 	struct vpe_notifications *n;
676 	unsigned int vpeflags;
677 	struct tc *t;
678 
679 	/* check we are the Master VPE */
680 	local_irq_save(flags);
681 	val = read_c0_vpeconf0();
682 	if (!(val & VPECONF0_MVP)) {
683 		printk(KERN_WARNING
684 		       "VPE loader: only Master VPE's are allowed to configure MT\n");
685 		local_irq_restore(flags);
686 
687 		return -1;
688 	}
689 
690 	dmt_flag = dmt();
691 	vpeflags = dvpe();
692 
693 	if (!list_empty(&v->tc)) {
694 		if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
695 			evpe(vpeflags);
696 			emt(dmt_flag);
697 			local_irq_restore(flags);
698 
699 			printk(KERN_WARNING
700 			       "VPE loader: TC %d is already in use.\n",
701                                t->index);
702 			return -ENOEXEC;
703 		}
704 	} else {
705 		evpe(vpeflags);
706 		emt(dmt_flag);
707 		local_irq_restore(flags);
708 
709 		printk(KERN_WARNING
710 		       "VPE loader: No TC's associated with VPE %d\n",
711 		       v->minor);
712 
713 		return -ENOEXEC;
714 	}
715 
716 	/* Put MVPE's into 'configuration state' */
717 	set_c0_mvpcontrol(MVPCONTROL_VPC);
718 
719 	settc(t->index);
720 
721 	/* should check it is halted, and not activated */
722 	if ((read_tc_c0_tcstatus() & TCSTATUS_A) || !(read_tc_c0_tchalt() & TCHALT_H)) {
723 		evpe(vpeflags);
724 		emt(dmt_flag);
725 		local_irq_restore(flags);
726 
727 		printk(KERN_WARNING "VPE loader: TC %d is already active!\n",
728 		       t->index);
729 
730 		return -ENOEXEC;
731 	}
732 
733 	/* Write the address we want it to start running from in the TCPC register. */
734 	write_tc_c0_tcrestart((unsigned long)v->__start);
735 	write_tc_c0_tccontext((unsigned long)0);
736 
737 	/*
738 	 * Mark the TC as activated, not interrupt exempt and not dynamically
739 	 * allocatable
740 	 */
741 	val = read_tc_c0_tcstatus();
742 	val = (val & ~(TCSTATUS_DA | TCSTATUS_IXMT)) | TCSTATUS_A;
743 	write_tc_c0_tcstatus(val);
744 
745 	write_tc_c0_tchalt(read_tc_c0_tchalt() & ~TCHALT_H);
746 
747 	/*
748 	 * The sde-kit passes 'memsize' to __start in $a3, so set something
749 	 * here...  Or set $a3 to zero and define DFLT_STACK_SIZE and
750 	 * DFLT_HEAP_SIZE when you compile your program
751 	 */
752 	mttgpr(6, v->ntcs);
753 	mttgpr(7, physical_memsize);
754 
755 	/* set up VPE1 */
756 	/*
757 	 * bind the TC to VPE 1 as late as possible so we only have the final
758 	 * VPE registers to set up, and so an EJTAG probe can trigger on it
759 	 */
760 	write_tc_c0_tcbind((read_tc_c0_tcbind() & ~TCBIND_CURVPE) | 1);
761 
762 	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~(VPECONF0_VPA));
763 
764 	back_to_back_c0_hazard();
765 
766 	/* Set up the XTC bit in vpeconf0 to point at our tc */
767 	write_vpe_c0_vpeconf0( (read_vpe_c0_vpeconf0() & ~(VPECONF0_XTC))
768 	                      | (t->index << VPECONF0_XTC_SHIFT));
769 
770 	back_to_back_c0_hazard();
771 
772 	/* enable this VPE */
773 	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA);
774 
775 	/* clear out any left overs from a previous program */
776 	write_vpe_c0_status(0);
777 	write_vpe_c0_cause(0);
778 
779 	/* take system out of configuration state */
780 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
781 
782 	/*
783 	 * SMTC/SMVP kernels manage VPE enable independently,
784 	 * but uniprocessor kernels need to turn it on, even
785 	 * if that wasn't the pre-dvpe() state.
786 	 */
787 #ifdef CONFIG_SMP
788 	evpe(vpeflags);
789 #else
790 	evpe(EVPE_ENABLE);
791 #endif
792 	emt(dmt_flag);
793 	local_irq_restore(flags);
794 
795 	list_for_each_entry(n, &v->notify, list)
796 		n->start(minor);
797 
798 	return 0;
799 }
800 
801 static int find_vpe_symbols(struct vpe * v, Elf_Shdr * sechdrs,
802 				      unsigned int symindex, const char *strtab,
803 				      struct module *mod)
804 {
805 	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
806 	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
807 
808 	for (i = 1; i < n; i++) {
809 		if (strcmp(strtab + sym[i].st_name, "__start") == 0) {
810 			v->__start = sym[i].st_value;
811 		}
812 
813 		if (strcmp(strtab + sym[i].st_name, "vpe_shared") == 0) {
814 			v->shared_ptr = (void *)sym[i].st_value;
815 		}
816 	}
817 
818 	if ( (v->__start == 0) || (v->shared_ptr == NULL))
819 		return -1;
820 
821 	return 0;
822 }
823 
824 /*
825  * Allocates a VPE with some program code space(the load address), copies the
826  * contents of the program (p)buffer performing relocatations/etc, free's it
827  * when finished.
828  */
829 static int vpe_elfload(struct vpe * v)
830 {
831 	Elf_Ehdr *hdr;
832 	Elf_Shdr *sechdrs;
833 	long err = 0;
834 	char *secstrings, *strtab = NULL;
835 	unsigned int len, i, symindex = 0, strindex = 0, relocate = 0;
836 	struct module mod;	// so we can re-use the relocations code
837 
838 	memset(&mod, 0, sizeof(struct module));
839 	strcpy(mod.name, "VPE loader");
840 
841 	hdr = (Elf_Ehdr *) v->pbuffer;
842 	len = v->plen;
843 
844 	/* Sanity checks against insmoding binaries or wrong arch,
845 	   weird elf version */
846 	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
847 	    || (hdr->e_type != ET_REL && hdr->e_type != ET_EXEC)
848 	    || !elf_check_arch(hdr)
849 	    || hdr->e_shentsize != sizeof(*sechdrs)) {
850 		printk(KERN_WARNING
851 		       "VPE loader: program wrong arch or weird elf version\n");
852 
853 		return -ENOEXEC;
854 	}
855 
856 	if (hdr->e_type == ET_REL)
857 		relocate = 1;
858 
859 	if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
860 		printk(KERN_ERR "VPE loader: program length %u truncated\n",
861 		       len);
862 
863 		return -ENOEXEC;
864 	}
865 
866 	/* Convenience variables */
867 	sechdrs = (void *)hdr + hdr->e_shoff;
868 	secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
869 	sechdrs[0].sh_addr = 0;
870 
871 	/* And these should exist, but gcc whinges if we don't init them */
872 	symindex = strindex = 0;
873 
874 	if (relocate) {
875 		for (i = 1; i < hdr->e_shnum; i++) {
876 			if (sechdrs[i].sh_type != SHT_NOBITS
877 			    && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) {
878 				printk(KERN_ERR "VPE program length %u truncated\n",
879 				       len);
880 				return -ENOEXEC;
881 			}
882 
883 			/* Mark all sections sh_addr with their address in the
884 			   temporary image. */
885 			sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
886 
887 			/* Internal symbols and strings. */
888 			if (sechdrs[i].sh_type == SHT_SYMTAB) {
889 				symindex = i;
890 				strindex = sechdrs[i].sh_link;
891 				strtab = (char *)hdr + sechdrs[strindex].sh_offset;
892 			}
893 		}
894 		layout_sections(&mod, hdr, sechdrs, secstrings);
895 	}
896 
897 	v->load_addr = alloc_progmem(mod.core_size);
898 	if (!v->load_addr)
899 		return -ENOMEM;
900 
901 	pr_info("VPE loader: loading to %p\n", v->load_addr);
902 
903 	if (relocate) {
904 		for (i = 0; i < hdr->e_shnum; i++) {
905 			void *dest;
906 
907 			if (!(sechdrs[i].sh_flags & SHF_ALLOC))
908 				continue;
909 
910 			dest = v->load_addr + sechdrs[i].sh_entsize;
911 
912 			if (sechdrs[i].sh_type != SHT_NOBITS)
913 				memcpy(dest, (void *)sechdrs[i].sh_addr,
914 				       sechdrs[i].sh_size);
915 			/* Update sh_addr to point to copy in image. */
916 			sechdrs[i].sh_addr = (unsigned long)dest;
917 
918 			printk(KERN_DEBUG " section sh_name %s sh_addr 0x%x\n",
919 			       secstrings + sechdrs[i].sh_name, sechdrs[i].sh_addr);
920 		}
921 
922  		/* Fix up syms, so that st_value is a pointer to location. */
923  		simplify_symbols(sechdrs, symindex, strtab, secstrings,
924  				 hdr->e_shnum, &mod);
925 
926  		/* Now do relocations. */
927  		for (i = 1; i < hdr->e_shnum; i++) {
928  			const char *strtab = (char *)sechdrs[strindex].sh_addr;
929  			unsigned int info = sechdrs[i].sh_info;
930 
931  			/* Not a valid relocation section? */
932  			if (info >= hdr->e_shnum)
933  				continue;
934 
935  			/* Don't bother with non-allocated sections */
936  			if (!(sechdrs[info].sh_flags & SHF_ALLOC))
937  				continue;
938 
939  			if (sechdrs[i].sh_type == SHT_REL)
940  				err = apply_relocations(sechdrs, strtab, symindex, i,
941  							&mod);
942  			else if (sechdrs[i].sh_type == SHT_RELA)
943  				err = apply_relocate_add(sechdrs, strtab, symindex, i,
944  							 &mod);
945  			if (err < 0)
946  				return err;
947 
948   		}
949   	} else {
950 		struct elf_phdr *phdr = (struct elf_phdr *) ((char *)hdr + hdr->e_phoff);
951 
952 		for (i = 0; i < hdr->e_phnum; i++) {
953 			if (phdr->p_type == PT_LOAD) {
954 				memcpy((void *)phdr->p_paddr,
955 				       (char *)hdr + phdr->p_offset,
956 				       phdr->p_filesz);
957 				memset((void *)phdr->p_paddr + phdr->p_filesz,
958 				       0, phdr->p_memsz - phdr->p_filesz);
959 		    }
960 		    phdr++;
961 		}
962 
963 		for (i = 0; i < hdr->e_shnum; i++) {
964  			/* Internal symbols and strings. */
965  			if (sechdrs[i].sh_type == SHT_SYMTAB) {
966  				symindex = i;
967  				strindex = sechdrs[i].sh_link;
968  				strtab = (char *)hdr + sechdrs[strindex].sh_offset;
969 
970  				/* mark the symtab's address for when we try to find the
971  				   magic symbols */
972  				sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
973  			}
974 		}
975 	}
976 
977 	/* make sure it's physically written out */
978 	flush_icache_range((unsigned long)v->load_addr,
979 			   (unsigned long)v->load_addr + v->len);
980 
981 	if ((find_vpe_symbols(v, sechdrs, symindex, strtab, &mod)) < 0) {
982 		if (v->__start == 0) {
983 			printk(KERN_WARNING "VPE loader: program does not contain "
984 			       "a __start symbol\n");
985 			return -ENOEXEC;
986 		}
987 
988 		if (v->shared_ptr == NULL)
989 			printk(KERN_WARNING "VPE loader: "
990 			       "program does not contain vpe_shared symbol.\n"
991 			       " Unable to use AMVP (AP/SP) facilities.\n");
992 	}
993 
994 	printk(" elf loaded\n");
995 	return 0;
996 }
997 
998 static void cleanup_tc(struct tc *tc)
999 {
1000 	unsigned long flags;
1001 	unsigned int mtflags, vpflags;
1002 	int tmp;
1003 
1004 	local_irq_save(flags);
1005 	mtflags = dmt();
1006 	vpflags = dvpe();
1007 	/* Put MVPE's into 'configuration state' */
1008 	set_c0_mvpcontrol(MVPCONTROL_VPC);
1009 
1010 	settc(tc->index);
1011 	tmp = read_tc_c0_tcstatus();
1012 
1013 	/* mark not allocated and not dynamically allocatable */
1014 	tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1015 	tmp |= TCSTATUS_IXMT;	/* interrupt exempt */
1016 	write_tc_c0_tcstatus(tmp);
1017 
1018 	write_tc_c0_tchalt(TCHALT_H);
1019 	mips_ihb();
1020 
1021 	/* bind it to anything other than VPE1 */
1022 //	write_tc_c0_tcbind(read_tc_c0_tcbind() & ~TCBIND_CURVPE); // | TCBIND_CURVPE
1023 
1024 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1025 	evpe(vpflags);
1026 	emt(mtflags);
1027 	local_irq_restore(flags);
1028 }
1029 
1030 static int getcwd(char *buff, int size)
1031 {
1032 	mm_segment_t old_fs;
1033 	int ret;
1034 
1035 	old_fs = get_fs();
1036 	set_fs(KERNEL_DS);
1037 
1038 	ret = sys_getcwd(buff, size);
1039 
1040 	set_fs(old_fs);
1041 
1042 	return ret;
1043 }
1044 
1045 /* checks VPE is unused and gets ready to load program  */
1046 static int vpe_open(struct inode *inode, struct file *filp)
1047 {
1048 	enum vpe_state state;
1049 	struct vpe_notifications *not;
1050 	struct vpe *v;
1051 	int ret, err = 0;
1052 
1053 	lock_kernel();
1054 	if (minor != iminor(inode)) {
1055 		/* assume only 1 device at the moment. */
1056 		printk(KERN_WARNING "VPE loader: only vpe1 is supported\n");
1057 		err = -ENODEV;
1058 		goto out;
1059 	}
1060 
1061 	if ((v = get_vpe(tclimit)) == NULL) {
1062 		printk(KERN_WARNING "VPE loader: unable to get vpe\n");
1063 		err = -ENODEV;
1064 		goto out;
1065 	}
1066 
1067 	state = xchg(&v->state, VPE_STATE_INUSE);
1068 	if (state != VPE_STATE_UNUSED) {
1069 		printk(KERN_DEBUG "VPE loader: tc in use dumping regs\n");
1070 
1071 		list_for_each_entry(not, &v->notify, list) {
1072 			not->stop(tclimit);
1073 		}
1074 
1075 		release_progmem(v->load_addr);
1076 		cleanup_tc(get_tc(tclimit));
1077 	}
1078 
1079 	/* this of-course trashes what was there before... */
1080 	v->pbuffer = vmalloc(P_SIZE);
1081 	v->plen = P_SIZE;
1082 	v->load_addr = NULL;
1083 	v->len = 0;
1084 
1085 	v->uid = filp->f_cred->fsuid;
1086 	v->gid = filp->f_cred->fsgid;
1087 
1088 #ifdef CONFIG_MIPS_APSP_KSPD
1089 	/* get kspd to tell us when a syscall_exit happens */
1090 	if (!kspd_events_reqd) {
1091 		kspd_notify(&kspd_events);
1092 		kspd_events_reqd++;
1093 	}
1094 #endif
1095 
1096 	v->cwd[0] = 0;
1097 	ret = getcwd(v->cwd, VPE_PATH_MAX);
1098 	if (ret < 0)
1099 		printk(KERN_WARNING "VPE loader: open, getcwd returned %d\n", ret);
1100 
1101 	v->shared_ptr = NULL;
1102 	v->__start = 0;
1103 
1104 out:
1105 	unlock_kernel();
1106 	return 0;
1107 }
1108 
1109 static int vpe_release(struct inode *inode, struct file *filp)
1110 {
1111 	struct vpe *v;
1112 	Elf_Ehdr *hdr;
1113 	int ret = 0;
1114 
1115 	v = get_vpe(tclimit);
1116 	if (v == NULL)
1117 		return -ENODEV;
1118 
1119 	hdr = (Elf_Ehdr *) v->pbuffer;
1120 	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) == 0) {
1121 		if (vpe_elfload(v) >= 0) {
1122 			vpe_run(v);
1123 		} else {
1124  			printk(KERN_WARNING "VPE loader: ELF load failed.\n");
1125 			ret = -ENOEXEC;
1126 		}
1127 	} else {
1128  		printk(KERN_WARNING "VPE loader: only elf files are supported\n");
1129 		ret = -ENOEXEC;
1130 	}
1131 
1132 	/* It's good to be able to run the SP and if it chokes have a look at
1133 	   the /dev/rt?. But if we reset the pointer to the shared struct we
1134 	   lose what has happened. So perhaps if garbage is sent to the vpe
1135 	   device, use it as a trigger for the reset. Hopefully a nice
1136 	   executable will be along shortly. */
1137 	if (ret < 0)
1138 		v->shared_ptr = NULL;
1139 
1140 	// cleanup any temp buffers
1141 	if (v->pbuffer)
1142 		vfree(v->pbuffer);
1143 	v->plen = 0;
1144 	return ret;
1145 }
1146 
1147 static ssize_t vpe_write(struct file *file, const char __user * buffer,
1148 			 size_t count, loff_t * ppos)
1149 {
1150 	size_t ret = count;
1151 	struct vpe *v;
1152 
1153 	if (iminor(file->f_path.dentry->d_inode) != minor)
1154 		return -ENODEV;
1155 
1156 	v = get_vpe(tclimit);
1157 	if (v == NULL)
1158 		return -ENODEV;
1159 
1160 	if (v->pbuffer == NULL) {
1161 		printk(KERN_ERR "VPE loader: no buffer for program\n");
1162 		return -ENOMEM;
1163 	}
1164 
1165 	if ((count + v->len) > v->plen) {
1166 		printk(KERN_WARNING
1167 		       "VPE loader: elf size too big. Perhaps strip uneeded symbols\n");
1168 		return -ENOMEM;
1169 	}
1170 
1171 	count -= copy_from_user(v->pbuffer + v->len, buffer, count);
1172 	if (!count)
1173 		return -EFAULT;
1174 
1175 	v->len += count;
1176 	return ret;
1177 }
1178 
1179 static const struct file_operations vpe_fops = {
1180 	.owner = THIS_MODULE,
1181 	.open = vpe_open,
1182 	.release = vpe_release,
1183 	.write = vpe_write
1184 };
1185 
1186 /* module wrapper entry points */
1187 /* give me a vpe */
1188 vpe_handle vpe_alloc(void)
1189 {
1190 	int i;
1191 	struct vpe *v;
1192 
1193 	/* find a vpe */
1194 	for (i = 1; i < MAX_VPES; i++) {
1195 		if ((v = get_vpe(i)) != NULL) {
1196 			v->state = VPE_STATE_INUSE;
1197 			return v;
1198 		}
1199 	}
1200 	return NULL;
1201 }
1202 
1203 EXPORT_SYMBOL(vpe_alloc);
1204 
1205 /* start running from here */
1206 int vpe_start(vpe_handle vpe, unsigned long start)
1207 {
1208 	struct vpe *v = vpe;
1209 
1210 	v->__start = start;
1211 	return vpe_run(v);
1212 }
1213 
1214 EXPORT_SYMBOL(vpe_start);
1215 
1216 /* halt it for now */
1217 int vpe_stop(vpe_handle vpe)
1218 {
1219 	struct vpe *v = vpe;
1220 	struct tc *t;
1221 	unsigned int evpe_flags;
1222 
1223 	evpe_flags = dvpe();
1224 
1225 	if ((t = list_entry(v->tc.next, struct tc, tc)) != NULL) {
1226 
1227 		settc(t->index);
1228 		write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1229 	}
1230 
1231 	evpe(evpe_flags);
1232 
1233 	return 0;
1234 }
1235 
1236 EXPORT_SYMBOL(vpe_stop);
1237 
1238 /* I've done with it thank you */
1239 int vpe_free(vpe_handle vpe)
1240 {
1241 	struct vpe *v = vpe;
1242 	struct tc *t;
1243 	unsigned int evpe_flags;
1244 
1245 	if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
1246 		return -ENOEXEC;
1247 	}
1248 
1249 	evpe_flags = dvpe();
1250 
1251 	/* Put MVPE's into 'configuration state' */
1252 	set_c0_mvpcontrol(MVPCONTROL_VPC);
1253 
1254 	settc(t->index);
1255 	write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1256 
1257 	/* halt the TC */
1258 	write_tc_c0_tchalt(TCHALT_H);
1259 	mips_ihb();
1260 
1261 	/* mark the TC unallocated */
1262 	write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A);
1263 
1264 	v->state = VPE_STATE_UNUSED;
1265 
1266 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1267 	evpe(evpe_flags);
1268 
1269 	return 0;
1270 }
1271 
1272 EXPORT_SYMBOL(vpe_free);
1273 
1274 void *vpe_get_shared(int index)
1275 {
1276 	struct vpe *v;
1277 
1278 	if ((v = get_vpe(index)) == NULL)
1279 		return NULL;
1280 
1281 	return v->shared_ptr;
1282 }
1283 
1284 EXPORT_SYMBOL(vpe_get_shared);
1285 
1286 int vpe_getuid(int index)
1287 {
1288 	struct vpe *v;
1289 
1290 	if ((v = get_vpe(index)) == NULL)
1291 		return -1;
1292 
1293 	return v->uid;
1294 }
1295 
1296 EXPORT_SYMBOL(vpe_getuid);
1297 
1298 int vpe_getgid(int index)
1299 {
1300 	struct vpe *v;
1301 
1302 	if ((v = get_vpe(index)) == NULL)
1303 		return -1;
1304 
1305 	return v->gid;
1306 }
1307 
1308 EXPORT_SYMBOL(vpe_getgid);
1309 
1310 int vpe_notify(int index, struct vpe_notifications *notify)
1311 {
1312 	struct vpe *v;
1313 
1314 	if ((v = get_vpe(index)) == NULL)
1315 		return -1;
1316 
1317 	list_add(&notify->list, &v->notify);
1318 	return 0;
1319 }
1320 
1321 EXPORT_SYMBOL(vpe_notify);
1322 
1323 char *vpe_getcwd(int index)
1324 {
1325 	struct vpe *v;
1326 
1327 	if ((v = get_vpe(index)) == NULL)
1328 		return NULL;
1329 
1330 	return v->cwd;
1331 }
1332 
1333 EXPORT_SYMBOL(vpe_getcwd);
1334 
1335 #ifdef CONFIG_MIPS_APSP_KSPD
1336 static void kspd_sp_exit( int sp_id)
1337 {
1338 	cleanup_tc(get_tc(sp_id));
1339 }
1340 #endif
1341 
1342 static ssize_t store_kill(struct device *dev, struct device_attribute *attr,
1343 			  const char *buf, size_t len)
1344 {
1345 	struct vpe *vpe = get_vpe(tclimit);
1346 	struct vpe_notifications *not;
1347 
1348 	list_for_each_entry(not, &vpe->notify, list) {
1349 		not->stop(tclimit);
1350 	}
1351 
1352 	release_progmem(vpe->load_addr);
1353 	cleanup_tc(get_tc(tclimit));
1354 	vpe_stop(vpe);
1355 	vpe_free(vpe);
1356 
1357 	return len;
1358 }
1359 
1360 static ssize_t show_ntcs(struct device *cd, struct device_attribute *attr,
1361 			 char *buf)
1362 {
1363 	struct vpe *vpe = get_vpe(tclimit);
1364 
1365 	return sprintf(buf, "%d\n", vpe->ntcs);
1366 }
1367 
1368 static ssize_t store_ntcs(struct device *dev, struct device_attribute *attr,
1369 			  const char *buf, size_t len)
1370 {
1371 	struct vpe *vpe = get_vpe(tclimit);
1372 	unsigned long new;
1373 	char *endp;
1374 
1375 	new = simple_strtoul(buf, &endp, 0);
1376 	if (endp == buf)
1377 		goto out_einval;
1378 
1379 	if (new == 0 || new > (hw_tcs - tclimit))
1380 		goto out_einval;
1381 
1382 	vpe->ntcs = new;
1383 
1384 	return len;
1385 
1386 out_einval:
1387 	return -EINVAL;
1388 }
1389 
1390 static struct device_attribute vpe_class_attributes[] = {
1391 	__ATTR(kill, S_IWUSR, NULL, store_kill),
1392 	__ATTR(ntcs, S_IRUGO | S_IWUSR, show_ntcs, store_ntcs),
1393 	{}
1394 };
1395 
1396 static void vpe_device_release(struct device *cd)
1397 {
1398 	kfree(cd);
1399 }
1400 
1401 struct class vpe_class = {
1402 	.name = "vpe",
1403 	.owner = THIS_MODULE,
1404 	.dev_release = vpe_device_release,
1405 	.dev_attrs = vpe_class_attributes,
1406 };
1407 
1408 struct device vpe_device;
1409 
1410 static int __init vpe_module_init(void)
1411 {
1412 	unsigned int mtflags, vpflags;
1413 	unsigned long flags, val;
1414 	struct vpe *v = NULL;
1415 	struct tc *t;
1416 	int tc, err;
1417 
1418 	if (!cpu_has_mipsmt) {
1419 		printk("VPE loader: not a MIPS MT capable processor\n");
1420 		return -ENODEV;
1421 	}
1422 
1423 	if (vpelimit == 0) {
1424 		printk(KERN_WARNING "No VPEs reserved for AP/SP, not "
1425 		       "initializing VPE loader.\nPass maxvpes=<n> argument as "
1426 		       "kernel argument\n");
1427 
1428 		return -ENODEV;
1429 	}
1430 
1431 	if (tclimit == 0) {
1432 		printk(KERN_WARNING "No TCs reserved for AP/SP, not "
1433 		       "initializing VPE loader.\nPass maxtcs=<n> argument as "
1434 		       "kernel argument\n");
1435 
1436 		return -ENODEV;
1437 	}
1438 
1439 	major = register_chrdev(0, module_name, &vpe_fops);
1440 	if (major < 0) {
1441 		printk("VPE loader: unable to register character device\n");
1442 		return major;
1443 	}
1444 
1445 	err = class_register(&vpe_class);
1446 	if (err) {
1447 		printk(KERN_ERR "vpe_class registration failed\n");
1448 		goto out_chrdev;
1449 	}
1450 
1451 	device_initialize(&vpe_device);
1452 	vpe_device.class	= &vpe_class,
1453 	vpe_device.parent	= NULL,
1454 	dev_set_name(&vpe_device, "vpe1");
1455 	vpe_device.devt = MKDEV(major, minor);
1456 	err = device_add(&vpe_device);
1457 	if (err) {
1458 		printk(KERN_ERR "Adding vpe_device failed\n");
1459 		goto out_class;
1460 	}
1461 
1462 	local_irq_save(flags);
1463 	mtflags = dmt();
1464 	vpflags = dvpe();
1465 
1466 	/* Put MVPE's into 'configuration state' */
1467 	set_c0_mvpcontrol(MVPCONTROL_VPC);
1468 
1469 	/* dump_mtregs(); */
1470 
1471 	val = read_c0_mvpconf0();
1472 	hw_tcs = (val & MVPCONF0_PTC) + 1;
1473 	hw_vpes = ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
1474 
1475 	for (tc = tclimit; tc < hw_tcs; tc++) {
1476 		/*
1477 		 * Must re-enable multithreading temporarily or in case we
1478 		 * reschedule send IPIs or similar we might hang.
1479 		 */
1480 		clear_c0_mvpcontrol(MVPCONTROL_VPC);
1481 		evpe(vpflags);
1482 		emt(mtflags);
1483 		local_irq_restore(flags);
1484 		t = alloc_tc(tc);
1485 		if (!t) {
1486 			err = -ENOMEM;
1487 			goto out;
1488 		}
1489 
1490 		local_irq_save(flags);
1491 		mtflags = dmt();
1492 		vpflags = dvpe();
1493 		set_c0_mvpcontrol(MVPCONTROL_VPC);
1494 
1495 		/* VPE's */
1496 		if (tc < hw_tcs) {
1497 			settc(tc);
1498 
1499 			if ((v = alloc_vpe(tc)) == NULL) {
1500 				printk(KERN_WARNING "VPE: unable to allocate VPE\n");
1501 
1502 				goto out_reenable;
1503 			}
1504 
1505 			v->ntcs = hw_tcs - tclimit;
1506 
1507 			/* add the tc to the list of this vpe's tc's. */
1508 			list_add(&t->tc, &v->tc);
1509 
1510 			/* deactivate all but vpe0 */
1511 			if (tc >= tclimit) {
1512 				unsigned long tmp = read_vpe_c0_vpeconf0();
1513 
1514 				tmp &= ~VPECONF0_VPA;
1515 
1516 				/* master VPE */
1517 				tmp |= VPECONF0_MVP;
1518 				write_vpe_c0_vpeconf0(tmp);
1519 			}
1520 
1521 			/* disable multi-threading with TC's */
1522 			write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE);
1523 
1524 			if (tc >= vpelimit) {
1525 				/*
1526 				 * Set config to be the same as vpe0,
1527 				 * particularly kseg0 coherency alg
1528 				 */
1529 				write_vpe_c0_config(read_c0_config());
1530 			}
1531 		}
1532 
1533 		/* TC's */
1534 		t->pvpe = v;	/* set the parent vpe */
1535 
1536 		if (tc >= tclimit) {
1537 			unsigned long tmp;
1538 
1539 			settc(tc);
1540 
1541 			/* Any TC that is bound to VPE0 gets left as is - in case
1542 			   we are running SMTC on VPE0. A TC that is bound to any
1543 			   other VPE gets bound to VPE0, ideally I'd like to make
1544 			   it homeless but it doesn't appear to let me bind a TC
1545 			   to a non-existent VPE. Which is perfectly reasonable.
1546 
1547 			   The (un)bound state is visible to an EJTAG probe so may
1548 			   notify GDB...
1549 			*/
1550 
1551 			if (((tmp = read_tc_c0_tcbind()) & TCBIND_CURVPE)) {
1552 				/* tc is bound >vpe0 */
1553 				write_tc_c0_tcbind(tmp & ~TCBIND_CURVPE);
1554 
1555 				t->pvpe = get_vpe(0);	/* set the parent vpe */
1556 			}
1557 
1558 			/* halt the TC */
1559 			write_tc_c0_tchalt(TCHALT_H);
1560 			mips_ihb();
1561 
1562 			tmp = read_tc_c0_tcstatus();
1563 
1564 			/* mark not activated and not dynamically allocatable */
1565 			tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1566 			tmp |= TCSTATUS_IXMT;	/* interrupt exempt */
1567 			write_tc_c0_tcstatus(tmp);
1568 		}
1569 	}
1570 
1571 out_reenable:
1572 	/* release config state */
1573 	clear_c0_mvpcontrol(MVPCONTROL_VPC);
1574 
1575 	evpe(vpflags);
1576 	emt(mtflags);
1577 	local_irq_restore(flags);
1578 
1579 #ifdef CONFIG_MIPS_APSP_KSPD
1580 	kspd_events.kspd_sp_exit = kspd_sp_exit;
1581 #endif
1582 	return 0;
1583 
1584 out_class:
1585 	class_unregister(&vpe_class);
1586 out_chrdev:
1587 	unregister_chrdev(major, module_name);
1588 
1589 out:
1590 	return err;
1591 }
1592 
1593 static void __exit vpe_module_exit(void)
1594 {
1595 	struct vpe *v, *n;
1596 
1597 	list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list) {
1598 		if (v->state != VPE_STATE_UNUSED) {
1599 			release_vpe(v);
1600 		}
1601 	}
1602 
1603 	device_del(&vpe_device);
1604 	unregister_chrdev(major, module_name);
1605 }
1606 
1607 module_init(vpe_module_init);
1608 module_exit(vpe_module_exit);
1609 MODULE_DESCRIPTION("MIPS VPE Loader");
1610 MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
1611 MODULE_LICENSE("GPL");
1612