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 environment 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/fs.h>
33 #include <linux/init.h>
34 #include <asm/uaccess.h>
35 #include <linux/slab.h>
36 #include <linux/list.h>
37 #include <linux/vmalloc.h>
38 #include <linux/elf.h>
39 #include <linux/seq_file.h>
40 #include <linux/syscalls.h>
41 #include <linux/moduleloader.h>
42 #include <linux/interrupt.h>
43 #include <linux/poll.h>
44 #include <linux/bootmem.h>
45 #include <asm/mipsregs.h>
46 #include <asm/mipsmtregs.h>
47 #include <asm/cacheflush.h>
48 #include <linux/atomic.h>
49 #include <asm/cpu.h>
50 #include <asm/mips_mt.h>
51 #include <asm/processor.h>
52 #include <asm/vpe.h>
53
54 typedef void *vpe_handle;
55
56 #ifndef ARCH_SHF_SMALL
57 #define ARCH_SHF_SMALL 0
58 #endif
59
60 /* If this is set, the section belongs in the init part of the module */
61 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
62
63 /*
64 * The number of TCs and VPEs physically available on the core
65 */
66 static int hw_tcs, hw_vpes;
67 static char module_name[] = "vpe";
68 static int major;
69 static const int minor = 1; /* fixed for now */
70
71 /* grab the likely amount of memory we will need. */
72 #ifdef CONFIG_MIPS_VPE_LOADER_TOM
73 #define P_SIZE (2 * 1024 * 1024)
74 #else
75 /* add an overhead to the max kmalloc size for non-striped symbols/etc */
76 #define P_SIZE (256 * 1024)
77 #endif
78
79 extern unsigned long physical_memsize;
80
81 #define MAX_VPES 16
82 #define VPE_PATH_MAX 256
83
84 enum vpe_state {
85 VPE_STATE_UNUSED = 0,
86 VPE_STATE_INUSE,
87 VPE_STATE_RUNNING
88 };
89
90 enum tc_state {
91 TC_STATE_UNUSED = 0,
92 TC_STATE_INUSE,
93 TC_STATE_RUNNING,
94 TC_STATE_DYNAMIC
95 };
96
97 struct vpe {
98 enum vpe_state state;
99
100 /* (device) minor associated with this vpe */
101 int minor;
102
103 /* elfloader stuff */
104 void *load_addr;
105 unsigned long len;
106 char *pbuffer;
107 unsigned long plen;
108 unsigned int uid, gid;
109 char cwd[VPE_PATH_MAX];
110
111 unsigned long __start;
112
113 /* tc's associated with this vpe */
114 struct list_head tc;
115
116 /* The list of vpe's */
117 struct list_head list;
118
119 /* shared symbol address */
120 void *shared_ptr;
121
122 /* the list of who wants to know when something major happens */
123 struct list_head notify;
124
125 unsigned int ntcs;
126 };
127
128 struct tc {
129 enum tc_state state;
130 int index;
131
132 struct vpe *pvpe; /* parent VPE */
133 struct list_head tc; /* The list of TC's with this VPE */
134 struct list_head list; /* The global list of tc's */
135 };
136
137 struct {
138 spinlock_t vpe_list_lock;
139 struct list_head vpe_list; /* Virtual processing elements */
140 spinlock_t tc_list_lock;
141 struct list_head tc_list; /* Thread contexts */
142 } vpecontrol = {
143 .vpe_list_lock = __SPIN_LOCK_UNLOCKED(vpe_list_lock),
144 .vpe_list = LIST_HEAD_INIT(vpecontrol.vpe_list),
145 .tc_list_lock = __SPIN_LOCK_UNLOCKED(tc_list_lock),
146 .tc_list = LIST_HEAD_INIT(vpecontrol.tc_list)
147 };
148
149 static void release_progmem(void *ptr);
150
151 /* get the vpe associated with this minor */
get_vpe(int minor)152 static struct vpe *get_vpe(int minor)
153 {
154 struct vpe *res, *v;
155
156 if (!cpu_has_mipsmt)
157 return NULL;
158
159 res = NULL;
160 spin_lock(&vpecontrol.vpe_list_lock);
161 list_for_each_entry(v, &vpecontrol.vpe_list, list) {
162 if (v->minor == minor) {
163 res = v;
164 break;
165 }
166 }
167 spin_unlock(&vpecontrol.vpe_list_lock);
168
169 return res;
170 }
171
172 /* get the vpe associated with this minor */
get_tc(int index)173 static struct tc *get_tc(int index)
174 {
175 struct tc *res, *t;
176
177 res = NULL;
178 spin_lock(&vpecontrol.tc_list_lock);
179 list_for_each_entry(t, &vpecontrol.tc_list, list) {
180 if (t->index == index) {
181 res = t;
182 break;
183 }
184 }
185 spin_unlock(&vpecontrol.tc_list_lock);
186
187 return res;
188 }
189
190 /* allocate a vpe and associate it with this minor (or index) */
alloc_vpe(int minor)191 static struct vpe *alloc_vpe(int minor)
192 {
193 struct vpe *v;
194
195 if ((v = kzalloc(sizeof(struct vpe), GFP_KERNEL)) == NULL)
196 return NULL;
197
198 INIT_LIST_HEAD(&v->tc);
199 spin_lock(&vpecontrol.vpe_list_lock);
200 list_add_tail(&v->list, &vpecontrol.vpe_list);
201 spin_unlock(&vpecontrol.vpe_list_lock);
202
203 INIT_LIST_HEAD(&v->notify);
204 v->minor = minor;
205
206 return v;
207 }
208
209 /* allocate a tc. At startup only tc0 is running, all other can be halted. */
alloc_tc(int index)210 static struct tc *alloc_tc(int index)
211 {
212 struct tc *tc;
213
214 if ((tc = kzalloc(sizeof(struct tc), GFP_KERNEL)) == NULL)
215 goto out;
216
217 INIT_LIST_HEAD(&tc->tc);
218 tc->index = index;
219
220 spin_lock(&vpecontrol.tc_list_lock);
221 list_add_tail(&tc->list, &vpecontrol.tc_list);
222 spin_unlock(&vpecontrol.tc_list_lock);
223
224 out:
225 return tc;
226 }
227
228 /* clean up and free everything */
release_vpe(struct vpe * v)229 static void release_vpe(struct vpe *v)
230 {
231 list_del(&v->list);
232 if (v->load_addr)
233 release_progmem(v);
234 kfree(v);
235 }
236
dump_mtregs(void)237 static void __maybe_unused dump_mtregs(void)
238 {
239 unsigned long val;
240
241 val = read_c0_config3();
242 printk("config3 0x%lx MT %ld\n", val,
243 (val & CONFIG3_MT) >> CONFIG3_MT_SHIFT);
244
245 val = read_c0_mvpcontrol();
246 printk("MVPControl 0x%lx, STLB %ld VPC %ld EVP %ld\n", val,
247 (val & MVPCONTROL_STLB) >> MVPCONTROL_STLB_SHIFT,
248 (val & MVPCONTROL_VPC) >> MVPCONTROL_VPC_SHIFT,
249 (val & MVPCONTROL_EVP));
250
251 val = read_c0_mvpconf0();
252 printk("mvpconf0 0x%lx, PVPE %ld PTC %ld M %ld\n", val,
253 (val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT,
254 val & MVPCONF0_PTC, (val & MVPCONF0_M) >> MVPCONF0_M_SHIFT);
255 }
256
257 /* Find some VPE program space */
alloc_progmem(unsigned long len)258 static void *alloc_progmem(unsigned long len)
259 {
260 void *addr;
261
262 #ifdef CONFIG_MIPS_VPE_LOADER_TOM
263 /*
264 * This means you must tell Linux to use less memory than you
265 * physically have, for example by passing a mem= boot argument.
266 */
267 addr = pfn_to_kaddr(max_low_pfn);
268 memset(addr, 0, len);
269 #else
270 /* simple grab some mem for now */
271 addr = kzalloc(len, GFP_KERNEL);
272 #endif
273
274 return addr;
275 }
276
release_progmem(void * ptr)277 static void release_progmem(void *ptr)
278 {
279 #ifndef CONFIG_MIPS_VPE_LOADER_TOM
280 kfree(ptr);
281 #endif
282 }
283
284 /* Update size with this section: return offset. */
get_offset(unsigned long * size,Elf_Shdr * sechdr)285 static long get_offset(unsigned long *size, Elf_Shdr * sechdr)
286 {
287 long ret;
288
289 ret = ALIGN(*size, sechdr->sh_addralign ? : 1);
290 *size = ret + sechdr->sh_size;
291 return ret;
292 }
293
294 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
295 might -- code, read-only data, read-write data, small data. Tally
296 sizes, and place the offsets into sh_entsize fields: high bit means it
297 belongs in init. */
layout_sections(struct module * mod,const Elf_Ehdr * hdr,Elf_Shdr * sechdrs,const char * secstrings)298 static void layout_sections(struct module *mod, const Elf_Ehdr * hdr,
299 Elf_Shdr * sechdrs, const char *secstrings)
300 {
301 static unsigned long const masks[][2] = {
302 /* NOTE: all executable code must be the first section
303 * in this array; otherwise modify the text_size
304 * finder in the two loops below */
305 {SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL},
306 {SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL},
307 {SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL},
308 {ARCH_SHF_SMALL | SHF_ALLOC, 0}
309 };
310 unsigned int m, i;
311
312 for (i = 0; i < hdr->e_shnum; i++)
313 sechdrs[i].sh_entsize = ~0UL;
314
315 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
316 for (i = 0; i < hdr->e_shnum; ++i) {
317 Elf_Shdr *s = &sechdrs[i];
318
319 // || strncmp(secstrings + s->sh_name, ".init", 5) == 0)
320 if ((s->sh_flags & masks[m][0]) != masks[m][0]
321 || (s->sh_flags & masks[m][1])
322 || s->sh_entsize != ~0UL)
323 continue;
324 s->sh_entsize =
325 get_offset((unsigned long *)&mod->core_size, s);
326 }
327
328 if (m == 0)
329 mod->core_text_size = mod->core_size;
330
331 }
332 }
333
334
335 /* from module-elf32.c, but subverted a little */
336
337 struct mips_hi16 {
338 struct mips_hi16 *next;
339 Elf32_Addr *addr;
340 Elf32_Addr value;
341 };
342
343 static struct mips_hi16 *mips_hi16_list;
344 static unsigned int gp_offs, gp_addr;
345
apply_r_mips_none(struct module * me,uint32_t * location,Elf32_Addr v)346 static int apply_r_mips_none(struct module *me, uint32_t *location,
347 Elf32_Addr v)
348 {
349 return 0;
350 }
351
apply_r_mips_gprel16(struct module * me,uint32_t * location,Elf32_Addr v)352 static int apply_r_mips_gprel16(struct module *me, uint32_t *location,
353 Elf32_Addr v)
354 {
355 int rel;
356
357 if( !(*location & 0xffff) ) {
358 rel = (int)v - gp_addr;
359 }
360 else {
361 /* .sbss + gp(relative) + offset */
362 /* kludge! */
363 rel = (int)(short)((int)v + gp_offs +
364 (int)(short)(*location & 0xffff) - gp_addr);
365 }
366
367 if( (rel > 32768) || (rel < -32768) ) {
368 printk(KERN_DEBUG "VPE loader: apply_r_mips_gprel16: "
369 "relative address 0x%x out of range of gp register\n",
370 rel);
371 return -ENOEXEC;
372 }
373
374 *location = (*location & 0xffff0000) | (rel & 0xffff);
375
376 return 0;
377 }
378
apply_r_mips_pc16(struct module * me,uint32_t * location,Elf32_Addr v)379 static int apply_r_mips_pc16(struct module *me, uint32_t *location,
380 Elf32_Addr v)
381 {
382 int rel;
383 rel = (((unsigned int)v - (unsigned int)location));
384 rel >>= 2; // because the offset is in _instructions_ not bytes.
385 rel -= 1; // and one instruction less due to the branch delay slot.
386
387 if( (rel > 32768) || (rel < -32768) ) {
388 printk(KERN_DEBUG "VPE loader: "
389 "apply_r_mips_pc16: relative address out of range 0x%x\n", rel);
390 return -ENOEXEC;
391 }
392
393 *location = (*location & 0xffff0000) | (rel & 0xffff);
394
395 return 0;
396 }
397
apply_r_mips_32(struct module * me,uint32_t * location,Elf32_Addr v)398 static int apply_r_mips_32(struct module *me, uint32_t *location,
399 Elf32_Addr v)
400 {
401 *location += v;
402
403 return 0;
404 }
405
apply_r_mips_26(struct module * me,uint32_t * location,Elf32_Addr v)406 static int apply_r_mips_26(struct module *me, uint32_t *location,
407 Elf32_Addr v)
408 {
409 if (v % 4) {
410 printk(KERN_DEBUG "VPE loader: apply_r_mips_26 "
411 " unaligned relocation\n");
412 return -ENOEXEC;
413 }
414
415 /*
416 * Not desperately convinced this is a good check of an overflow condition
417 * anyway. But it gets in the way of handling undefined weak symbols which
418 * we want to set to zero.
419 * if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
420 * printk(KERN_ERR
421 * "module %s: relocation overflow\n",
422 * me->name);
423 * return -ENOEXEC;
424 * }
425 */
426
427 *location = (*location & ~0x03ffffff) |
428 ((*location + (v >> 2)) & 0x03ffffff);
429 return 0;
430 }
431
apply_r_mips_hi16(struct module * me,uint32_t * location,Elf32_Addr v)432 static int apply_r_mips_hi16(struct module *me, uint32_t *location,
433 Elf32_Addr v)
434 {
435 struct mips_hi16 *n;
436
437 /*
438 * We cannot relocate this one now because we don't know the value of
439 * the carry we need to add. Save the information, and let LO16 do the
440 * actual relocation.
441 */
442 n = kmalloc(sizeof *n, GFP_KERNEL);
443 if (!n)
444 return -ENOMEM;
445
446 n->addr = location;
447 n->value = v;
448 n->next = mips_hi16_list;
449 mips_hi16_list = n;
450
451 return 0;
452 }
453
apply_r_mips_lo16(struct module * me,uint32_t * location,Elf32_Addr v)454 static int apply_r_mips_lo16(struct module *me, uint32_t *location,
455 Elf32_Addr v)
456 {
457 unsigned long insnlo = *location;
458 Elf32_Addr val, vallo;
459 struct mips_hi16 *l, *next;
460
461 /* Sign extend the addend we extract from the lo insn. */
462 vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
463
464 if (mips_hi16_list != NULL) {
465
466 l = mips_hi16_list;
467 while (l != NULL) {
468 unsigned long insn;
469
470 /*
471 * The value for the HI16 had best be the same.
472 */
473 if (v != l->value) {
474 printk(KERN_DEBUG "VPE loader: "
475 "apply_r_mips_lo16/hi16: \t"
476 "inconsistent value information\n");
477 goto out_free;
478 }
479
480 /*
481 * Do the HI16 relocation. Note that we actually don't
482 * need to know anything about the LO16 itself, except
483 * where to find the low 16 bits of the addend needed
484 * by the LO16.
485 */
486 insn = *l->addr;
487 val = ((insn & 0xffff) << 16) + vallo;
488 val += v;
489
490 /*
491 * Account for the sign extension that will happen in
492 * the low bits.
493 */
494 val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
495
496 insn = (insn & ~0xffff) | val;
497 *l->addr = insn;
498
499 next = l->next;
500 kfree(l);
501 l = next;
502 }
503
504 mips_hi16_list = NULL;
505 }
506
507 /*
508 * Ok, we're done with the HI16 relocs. Now deal with the LO16.
509 */
510 val = v + vallo;
511 insnlo = (insnlo & ~0xffff) | (val & 0xffff);
512 *location = insnlo;
513
514 return 0;
515
516 out_free:
517 while (l != NULL) {
518 next = l->next;
519 kfree(l);
520 l = next;
521 }
522 mips_hi16_list = NULL;
523
524 return -ENOEXEC;
525 }
526
527 static int (*reloc_handlers[]) (struct module *me, uint32_t *location,
528 Elf32_Addr v) = {
529 [R_MIPS_NONE] = apply_r_mips_none,
530 [R_MIPS_32] = apply_r_mips_32,
531 [R_MIPS_26] = apply_r_mips_26,
532 [R_MIPS_HI16] = apply_r_mips_hi16,
533 [R_MIPS_LO16] = apply_r_mips_lo16,
534 [R_MIPS_GPREL16] = apply_r_mips_gprel16,
535 [R_MIPS_PC16] = apply_r_mips_pc16
536 };
537
538 static char *rstrs[] = {
539 [R_MIPS_NONE] = "MIPS_NONE",
540 [R_MIPS_32] = "MIPS_32",
541 [R_MIPS_26] = "MIPS_26",
542 [R_MIPS_HI16] = "MIPS_HI16",
543 [R_MIPS_LO16] = "MIPS_LO16",
544 [R_MIPS_GPREL16] = "MIPS_GPREL16",
545 [R_MIPS_PC16] = "MIPS_PC16"
546 };
547
apply_relocations(Elf32_Shdr * sechdrs,const char * strtab,unsigned int symindex,unsigned int relsec,struct module * me)548 static int apply_relocations(Elf32_Shdr *sechdrs,
549 const char *strtab,
550 unsigned int symindex,
551 unsigned int relsec,
552 struct module *me)
553 {
554 Elf32_Rel *rel = (void *) sechdrs[relsec].sh_addr;
555 Elf32_Sym *sym;
556 uint32_t *location;
557 unsigned int i;
558 Elf32_Addr v;
559 int res;
560
561 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
562 Elf32_Word r_info = rel[i].r_info;
563
564 /* This is where to make the change */
565 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
566 + rel[i].r_offset;
567 /* This is the symbol it is referring to */
568 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
569 + ELF32_R_SYM(r_info);
570
571 if (!sym->st_value) {
572 printk(KERN_DEBUG "%s: undefined weak symbol %s\n",
573 me->name, strtab + sym->st_name);
574 /* just print the warning, dont barf */
575 }
576
577 v = sym->st_value;
578
579 res = reloc_handlers[ELF32_R_TYPE(r_info)](me, location, v);
580 if( res ) {
581 char *r = rstrs[ELF32_R_TYPE(r_info)];
582 printk(KERN_WARNING "VPE loader: .text+0x%x "
583 "relocation type %s for symbol \"%s\" failed\n",
584 rel[i].r_offset, r ? r : "UNKNOWN",
585 strtab + sym->st_name);
586 return res;
587 }
588 }
589
590 return 0;
591 }
592
save_gp_address(unsigned int secbase,unsigned int rel)593 static inline void save_gp_address(unsigned int secbase, unsigned int rel)
594 {
595 gp_addr = secbase + rel;
596 gp_offs = gp_addr - (secbase & 0xffff0000);
597 }
598 /* end module-elf32.c */
599
600
601
602 /* Change all symbols so that sh_value encodes the pointer directly. */
simplify_symbols(Elf_Shdr * sechdrs,unsigned int symindex,const char * strtab,const char * secstrings,unsigned int nsecs,struct module * mod)603 static void simplify_symbols(Elf_Shdr * sechdrs,
604 unsigned int symindex,
605 const char *strtab,
606 const char *secstrings,
607 unsigned int nsecs, struct module *mod)
608 {
609 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
610 unsigned long secbase, bssbase = 0;
611 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
612 int size;
613
614 /* find the .bss section for COMMON symbols */
615 for (i = 0; i < nsecs; i++) {
616 if (strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) == 0) {
617 bssbase = sechdrs[i].sh_addr;
618 break;
619 }
620 }
621
622 for (i = 1; i < n; i++) {
623 switch (sym[i].st_shndx) {
624 case SHN_COMMON:
625 /* Allocate space for the symbol in the .bss section.
626 st_value is currently size.
627 We want it to have the address of the symbol. */
628
629 size = sym[i].st_value;
630 sym[i].st_value = bssbase;
631
632 bssbase += size;
633 break;
634
635 case SHN_ABS:
636 /* Don't need to do anything */
637 break;
638
639 case SHN_UNDEF:
640 /* ret = -ENOENT; */
641 break;
642
643 case SHN_MIPS_SCOMMON:
644 printk(KERN_DEBUG "simplify_symbols: ignoring SHN_MIPS_SCOMMON "
645 "symbol <%s> st_shndx %d\n", strtab + sym[i].st_name,
646 sym[i].st_shndx);
647 // .sbss section
648 break;
649
650 default:
651 secbase = sechdrs[sym[i].st_shndx].sh_addr;
652
653 if (strncmp(strtab + sym[i].st_name, "_gp", 3) == 0) {
654 save_gp_address(secbase, sym[i].st_value);
655 }
656
657 sym[i].st_value += secbase;
658 break;
659 }
660 }
661 }
662
663 #ifdef DEBUG_ELFLOADER
dump_elfsymbols(Elf_Shdr * sechdrs,unsigned int symindex,const char * strtab,struct module * mod)664 static void dump_elfsymbols(Elf_Shdr * sechdrs, unsigned int symindex,
665 const char *strtab, struct module *mod)
666 {
667 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
668 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
669
670 printk(KERN_DEBUG "dump_elfsymbols: n %d\n", n);
671 for (i = 1; i < n; i++) {
672 printk(KERN_DEBUG " i %d name <%s> 0x%x\n", i,
673 strtab + sym[i].st_name, sym[i].st_value);
674 }
675 }
676 #endif
677
678 /* We are prepared so configure and start the VPE... */
vpe_run(struct vpe * v)679 static int vpe_run(struct vpe * v)
680 {
681 unsigned long flags, val, dmt_flag;
682 struct vpe_notifications *n;
683 unsigned int vpeflags;
684 struct tc *t;
685
686 /* check we are the Master VPE */
687 local_irq_save(flags);
688 val = read_c0_vpeconf0();
689 if (!(val & VPECONF0_MVP)) {
690 printk(KERN_WARNING
691 "VPE loader: only Master VPE's are allowed to configure MT\n");
692 local_irq_restore(flags);
693
694 return -1;
695 }
696
697 dmt_flag = dmt();
698 vpeflags = dvpe();
699
700 if (list_empty(&v->tc)) {
701 evpe(vpeflags);
702 emt(dmt_flag);
703 local_irq_restore(flags);
704
705 printk(KERN_WARNING
706 "VPE loader: No TC's associated with VPE %d\n",
707 v->minor);
708
709 return -ENOEXEC;
710 }
711
712 t = list_first_entry(&v->tc, struct tc, tc);
713
714 /* Put MVPE's into 'configuration state' */
715 set_c0_mvpcontrol(MVPCONTROL_VPC);
716
717 settc(t->index);
718
719 /* should check it is halted, and not activated */
720 if ((read_tc_c0_tcstatus() & TCSTATUS_A) || !(read_tc_c0_tchalt() & TCHALT_H)) {
721 evpe(vpeflags);
722 emt(dmt_flag);
723 local_irq_restore(flags);
724
725 printk(KERN_WARNING "VPE loader: TC %d is already active!\n",
726 t->index);
727
728 return -ENOEXEC;
729 }
730
731 /* Write the address we want it to start running from in the TCPC register. */
732 write_tc_c0_tcrestart((unsigned long)v->__start);
733 write_tc_c0_tccontext((unsigned long)0);
734
735 /*
736 * Mark the TC as activated, not interrupt exempt and not dynamically
737 * allocatable
738 */
739 val = read_tc_c0_tcstatus();
740 val = (val & ~(TCSTATUS_DA | TCSTATUS_IXMT)) | TCSTATUS_A;
741 write_tc_c0_tcstatus(val);
742
743 write_tc_c0_tchalt(read_tc_c0_tchalt() & ~TCHALT_H);
744
745 /*
746 * The sde-kit passes 'memsize' to __start in $a3, so set something
747 * here... Or set $a3 to zero and define DFLT_STACK_SIZE and
748 * DFLT_HEAP_SIZE when you compile your program
749 */
750 mttgpr(6, v->ntcs);
751 mttgpr(7, physical_memsize);
752
753 /* set up VPE1 */
754 /*
755 * bind the TC to VPE 1 as late as possible so we only have the final
756 * VPE registers to set up, and so an EJTAG probe can trigger on it
757 */
758 write_tc_c0_tcbind((read_tc_c0_tcbind() & ~TCBIND_CURVPE) | 1);
759
760 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~(VPECONF0_VPA));
761
762 back_to_back_c0_hazard();
763
764 /* Set up the XTC bit in vpeconf0 to point at our tc */
765 write_vpe_c0_vpeconf0( (read_vpe_c0_vpeconf0() & ~(VPECONF0_XTC))
766 | (t->index << VPECONF0_XTC_SHIFT));
767
768 back_to_back_c0_hazard();
769
770 /* enable this VPE */
771 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA);
772
773 /* clear out any left overs from a previous program */
774 write_vpe_c0_status(0);
775 write_vpe_c0_cause(0);
776
777 /* take system out of configuration state */
778 clear_c0_mvpcontrol(MVPCONTROL_VPC);
779
780 /*
781 * SMTC/SMVP kernels manage VPE enable independently,
782 * but uniprocessor kernels need to turn it on, even
783 * if that wasn't the pre-dvpe() state.
784 */
785 #ifdef CONFIG_SMP
786 evpe(vpeflags);
787 #else
788 evpe(EVPE_ENABLE);
789 #endif
790 emt(dmt_flag);
791 local_irq_restore(flags);
792
793 list_for_each_entry(n, &v->notify, list)
794 n->start(minor);
795
796 return 0;
797 }
798
find_vpe_symbols(struct vpe * v,Elf_Shdr * sechdrs,unsigned int symindex,const char * strtab,struct module * mod)799 static int find_vpe_symbols(struct vpe * v, Elf_Shdr * sechdrs,
800 unsigned int symindex, const char *strtab,
801 struct module *mod)
802 {
803 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
804 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
805
806 for (i = 1; i < n; i++) {
807 if (strcmp(strtab + sym[i].st_name, "__start") == 0) {
808 v->__start = sym[i].st_value;
809 }
810
811 if (strcmp(strtab + sym[i].st_name, "vpe_shared") == 0) {
812 v->shared_ptr = (void *)sym[i].st_value;
813 }
814 }
815
816 if ( (v->__start == 0) || (v->shared_ptr == NULL))
817 return -1;
818
819 return 0;
820 }
821
822 /*
823 * Allocates a VPE with some program code space(the load address), copies the
824 * contents of the program (p)buffer performing relocatations/etc, free's it
825 * when finished.
826 */
vpe_elfload(struct vpe * v)827 static int vpe_elfload(struct vpe * v)
828 {
829 Elf_Ehdr *hdr;
830 Elf_Shdr *sechdrs;
831 long err = 0;
832 char *secstrings, *strtab = NULL;
833 unsigned int len, i, symindex = 0, strindex = 0, relocate = 0;
834 struct module mod; // so we can re-use the relocations code
835 mm_segment_t old_fs;
836
837 memset(&mod, 0, sizeof(struct module));
838 strcpy(mod.name, "VPE loader");
839
840 hdr = (Elf_Ehdr *) v->pbuffer;
841 len = v->plen;
842
843 /* Sanity checks against insmoding binaries or wrong arch,
844 weird elf version */
845 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
846 || (hdr->e_type != ET_REL && hdr->e_type != ET_EXEC)
847 || !elf_check_arch(hdr)
848 || hdr->e_shentsize != sizeof(*sechdrs)) {
849 printk(KERN_WARNING
850 "VPE loader: program wrong arch or weird elf version\n");
851
852 return -ENOEXEC;
853 }
854
855 if (hdr->e_type == ET_REL)
856 relocate = 1;
857
858 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
859 printk(KERN_ERR "VPE loader: program length %u truncated\n",
860 len);
861
862 return -ENOEXEC;
863 }
864
865 /* Convenience variables */
866 sechdrs = (void *)hdr + hdr->e_shoff;
867 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
868 sechdrs[0].sh_addr = 0;
869
870 /* And these should exist, but gcc whinges if we don't init them */
871 symindex = strindex = 0;
872
873 if (relocate) {
874 for (i = 1; i < hdr->e_shnum; i++) {
875 if (sechdrs[i].sh_type != SHT_NOBITS
876 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) {
877 printk(KERN_ERR "VPE program length %u truncated\n",
878 len);
879 return -ENOEXEC;
880 }
881
882 /* Mark all sections sh_addr with their address in the
883 temporary image. */
884 sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
885
886 /* Internal symbols and strings. */
887 if (sechdrs[i].sh_type == SHT_SYMTAB) {
888 symindex = i;
889 strindex = sechdrs[i].sh_link;
890 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
891 }
892 }
893 layout_sections(&mod, hdr, sechdrs, secstrings);
894 }
895
896 v->load_addr = alloc_progmem(mod.core_size);
897 if (!v->load_addr)
898 return -ENOMEM;
899
900 pr_info("VPE loader: loading to %p\n", v->load_addr);
901
902 if (relocate) {
903 for (i = 0; i < hdr->e_shnum; i++) {
904 void *dest;
905
906 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
907 continue;
908
909 dest = v->load_addr + sechdrs[i].sh_entsize;
910
911 if (sechdrs[i].sh_type != SHT_NOBITS)
912 memcpy(dest, (void *)sechdrs[i].sh_addr,
913 sechdrs[i].sh_size);
914 /* Update sh_addr to point to copy in image. */
915 sechdrs[i].sh_addr = (unsigned long)dest;
916
917 printk(KERN_DEBUG " section sh_name %s sh_addr 0x%x\n",
918 secstrings + sechdrs[i].sh_name, sechdrs[i].sh_addr);
919 }
920
921 /* Fix up syms, so that st_value is a pointer to location. */
922 simplify_symbols(sechdrs, symindex, strtab, secstrings,
923 hdr->e_shnum, &mod);
924
925 /* Now do relocations. */
926 for (i = 1; i < hdr->e_shnum; i++) {
927 const char *strtab = (char *)sechdrs[strindex].sh_addr;
928 unsigned int info = sechdrs[i].sh_info;
929
930 /* Not a valid relocation section? */
931 if (info >= hdr->e_shnum)
932 continue;
933
934 /* Don't bother with non-allocated sections */
935 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
936 continue;
937
938 if (sechdrs[i].sh_type == SHT_REL)
939 err = apply_relocations(sechdrs, strtab, symindex, i,
940 &mod);
941 else if (sechdrs[i].sh_type == SHT_RELA)
942 err = apply_relocate_add(sechdrs, strtab, symindex, i,
943 &mod);
944 if (err < 0)
945 return err;
946
947 }
948 } else {
949 struct elf_phdr *phdr = (struct elf_phdr *) ((char *)hdr + hdr->e_phoff);
950
951 for (i = 0; i < hdr->e_phnum; i++) {
952 if (phdr->p_type == PT_LOAD) {
953 memcpy((void *)phdr->p_paddr,
954 (char *)hdr + phdr->p_offset,
955 phdr->p_filesz);
956 memset((void *)phdr->p_paddr + phdr->p_filesz,
957 0, phdr->p_memsz - phdr->p_filesz);
958 }
959 phdr++;
960 }
961
962 for (i = 0; i < hdr->e_shnum; i++) {
963 /* Internal symbols and strings. */
964 if (sechdrs[i].sh_type == SHT_SYMTAB) {
965 symindex = i;
966 strindex = sechdrs[i].sh_link;
967 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
968
969 /* mark the symtab's address for when we try to find the
970 magic symbols */
971 sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
972 }
973 }
974 }
975
976 /* make sure it's physically written out */
977 /* flush the icache in correct context */
978 old_fs = get_fs();
979 set_fs(KERNEL_DS);
980 flush_icache_range((unsigned long)v->load_addr,
981 (unsigned long)v->load_addr + v->len);
982 set_fs(old_fs);
983
984 if ((find_vpe_symbols(v, sechdrs, symindex, strtab, &mod)) < 0) {
985 if (v->__start == 0) {
986 printk(KERN_WARNING "VPE loader: program does not contain "
987 "a __start symbol\n");
988 return -ENOEXEC;
989 }
990
991 if (v->shared_ptr == NULL)
992 printk(KERN_WARNING "VPE loader: "
993 "program does not contain vpe_shared symbol.\n"
994 " Unable to use AMVP (AP/SP) facilities.\n");
995 }
996
997 printk(" elf loaded\n");
998 return 0;
999 }
1000
cleanup_tc(struct tc * tc)1001 static void cleanup_tc(struct tc *tc)
1002 {
1003 unsigned long flags;
1004 unsigned int mtflags, vpflags;
1005 int tmp;
1006
1007 local_irq_save(flags);
1008 mtflags = dmt();
1009 vpflags = dvpe();
1010 /* Put MVPE's into 'configuration state' */
1011 set_c0_mvpcontrol(MVPCONTROL_VPC);
1012
1013 settc(tc->index);
1014 tmp = read_tc_c0_tcstatus();
1015
1016 /* mark not allocated and not dynamically allocatable */
1017 tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1018 tmp |= TCSTATUS_IXMT; /* interrupt exempt */
1019 write_tc_c0_tcstatus(tmp);
1020
1021 write_tc_c0_tchalt(TCHALT_H);
1022 mips_ihb();
1023
1024 /* bind it to anything other than VPE1 */
1025 // write_tc_c0_tcbind(read_tc_c0_tcbind() & ~TCBIND_CURVPE); // | TCBIND_CURVPE
1026
1027 clear_c0_mvpcontrol(MVPCONTROL_VPC);
1028 evpe(vpflags);
1029 emt(mtflags);
1030 local_irq_restore(flags);
1031 }
1032
getcwd(char * buff,int size)1033 static int getcwd(char *buff, int size)
1034 {
1035 mm_segment_t old_fs;
1036 int ret;
1037
1038 old_fs = get_fs();
1039 set_fs(KERNEL_DS);
1040
1041 ret = sys_getcwd(buff, size);
1042
1043 set_fs(old_fs);
1044
1045 return ret;
1046 }
1047
1048 /* checks VPE is unused and gets ready to load program */
vpe_open(struct inode * inode,struct file * filp)1049 static int vpe_open(struct inode *inode, struct file *filp)
1050 {
1051 enum vpe_state state;
1052 struct vpe_notifications *not;
1053 struct vpe *v;
1054 int ret;
1055
1056 if (minor != iminor(inode)) {
1057 /* assume only 1 device at the moment. */
1058 pr_warning("VPE loader: only vpe1 is supported\n");
1059
1060 return -ENODEV;
1061 }
1062
1063 if ((v = get_vpe(tclimit)) == NULL) {
1064 pr_warning("VPE loader: unable to get vpe\n");
1065
1066 return -ENODEV;
1067 }
1068
1069 state = xchg(&v->state, VPE_STATE_INUSE);
1070 if (state != VPE_STATE_UNUSED) {
1071 printk(KERN_DEBUG "VPE loader: tc in use dumping regs\n");
1072
1073 list_for_each_entry(not, &v->notify, list) {
1074 not->stop(tclimit);
1075 }
1076
1077 release_progmem(v->load_addr);
1078 cleanup_tc(get_tc(tclimit));
1079 }
1080
1081 /* this of-course trashes what was there before... */
1082 v->pbuffer = vmalloc(P_SIZE);
1083 if (!v->pbuffer) {
1084 pr_warning("VPE loader: unable to allocate memory\n");
1085 return -ENOMEM;
1086 }
1087 v->plen = P_SIZE;
1088 v->load_addr = NULL;
1089 v->len = 0;
1090
1091 v->uid = filp->f_cred->fsuid;
1092 v->gid = filp->f_cred->fsgid;
1093
1094 v->cwd[0] = 0;
1095 ret = getcwd(v->cwd, VPE_PATH_MAX);
1096 if (ret < 0)
1097 printk(KERN_WARNING "VPE loader: open, getcwd returned %d\n", ret);
1098
1099 v->shared_ptr = NULL;
1100 v->__start = 0;
1101
1102 return 0;
1103 }
1104
vpe_release(struct inode * inode,struct file * filp)1105 static int vpe_release(struct inode *inode, struct file *filp)
1106 {
1107 struct vpe *v;
1108 Elf_Ehdr *hdr;
1109 int ret = 0;
1110
1111 v = get_vpe(tclimit);
1112 if (v == NULL)
1113 return -ENODEV;
1114
1115 hdr = (Elf_Ehdr *) v->pbuffer;
1116 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) == 0) {
1117 if (vpe_elfload(v) >= 0) {
1118 vpe_run(v);
1119 } else {
1120 printk(KERN_WARNING "VPE loader: ELF load failed.\n");
1121 ret = -ENOEXEC;
1122 }
1123 } else {
1124 printk(KERN_WARNING "VPE loader: only elf files are supported\n");
1125 ret = -ENOEXEC;
1126 }
1127
1128 /* It's good to be able to run the SP and if it chokes have a look at
1129 the /dev/rt?. But if we reset the pointer to the shared struct we
1130 lose what has happened. So perhaps if garbage is sent to the vpe
1131 device, use it as a trigger for the reset. Hopefully a nice
1132 executable will be along shortly. */
1133 if (ret < 0)
1134 v->shared_ptr = NULL;
1135
1136 vfree(v->pbuffer);
1137 v->plen = 0;
1138
1139 return ret;
1140 }
1141
vpe_write(struct file * file,const char __user * buffer,size_t count,loff_t * ppos)1142 static ssize_t vpe_write(struct file *file, const char __user * buffer,
1143 size_t count, loff_t * ppos)
1144 {
1145 size_t ret = count;
1146 struct vpe *v;
1147
1148 if (iminor(file_inode(file)) != minor)
1149 return -ENODEV;
1150
1151 v = get_vpe(tclimit);
1152 if (v == NULL)
1153 return -ENODEV;
1154
1155 if ((count + v->len) > v->plen) {
1156 printk(KERN_WARNING
1157 "VPE loader: elf size too big. Perhaps strip uneeded symbols\n");
1158 return -ENOMEM;
1159 }
1160
1161 count -= copy_from_user(v->pbuffer + v->len, buffer, count);
1162 if (!count)
1163 return -EFAULT;
1164
1165 v->len += count;
1166 return ret;
1167 }
1168
1169 static const struct file_operations vpe_fops = {
1170 .owner = THIS_MODULE,
1171 .open = vpe_open,
1172 .release = vpe_release,
1173 .write = vpe_write,
1174 .llseek = noop_llseek,
1175 };
1176
1177 /* module wrapper entry points */
1178 /* give me a vpe */
vpe_alloc(void)1179 vpe_handle vpe_alloc(void)
1180 {
1181 int i;
1182 struct vpe *v;
1183
1184 /* find a vpe */
1185 for (i = 1; i < MAX_VPES; i++) {
1186 if ((v = get_vpe(i)) != NULL) {
1187 v->state = VPE_STATE_INUSE;
1188 return v;
1189 }
1190 }
1191 return NULL;
1192 }
1193
1194 EXPORT_SYMBOL(vpe_alloc);
1195
1196 /* start running from here */
vpe_start(vpe_handle vpe,unsigned long start)1197 int vpe_start(vpe_handle vpe, unsigned long start)
1198 {
1199 struct vpe *v = vpe;
1200
1201 v->__start = start;
1202 return vpe_run(v);
1203 }
1204
1205 EXPORT_SYMBOL(vpe_start);
1206
1207 /* halt it for now */
vpe_stop(vpe_handle vpe)1208 int vpe_stop(vpe_handle vpe)
1209 {
1210 struct vpe *v = vpe;
1211 struct tc *t;
1212 unsigned int evpe_flags;
1213
1214 evpe_flags = dvpe();
1215
1216 if ((t = list_entry(v->tc.next, struct tc, tc)) != NULL) {
1217
1218 settc(t->index);
1219 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1220 }
1221
1222 evpe(evpe_flags);
1223
1224 return 0;
1225 }
1226
1227 EXPORT_SYMBOL(vpe_stop);
1228
1229 /* I've done with it thank you */
vpe_free(vpe_handle vpe)1230 int vpe_free(vpe_handle vpe)
1231 {
1232 struct vpe *v = vpe;
1233 struct tc *t;
1234 unsigned int evpe_flags;
1235
1236 if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
1237 return -ENOEXEC;
1238 }
1239
1240 evpe_flags = dvpe();
1241
1242 /* Put MVPE's into 'configuration state' */
1243 set_c0_mvpcontrol(MVPCONTROL_VPC);
1244
1245 settc(t->index);
1246 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1247
1248 /* halt the TC */
1249 write_tc_c0_tchalt(TCHALT_H);
1250 mips_ihb();
1251
1252 /* mark the TC unallocated */
1253 write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A);
1254
1255 v->state = VPE_STATE_UNUSED;
1256
1257 clear_c0_mvpcontrol(MVPCONTROL_VPC);
1258 evpe(evpe_flags);
1259
1260 return 0;
1261 }
1262
1263 EXPORT_SYMBOL(vpe_free);
1264
vpe_get_shared(int index)1265 void *vpe_get_shared(int index)
1266 {
1267 struct vpe *v;
1268
1269 if ((v = get_vpe(index)) == NULL)
1270 return NULL;
1271
1272 return v->shared_ptr;
1273 }
1274
1275 EXPORT_SYMBOL(vpe_get_shared);
1276
vpe_getuid(int index)1277 int vpe_getuid(int index)
1278 {
1279 struct vpe *v;
1280
1281 if ((v = get_vpe(index)) == NULL)
1282 return -1;
1283
1284 return v->uid;
1285 }
1286
1287 EXPORT_SYMBOL(vpe_getuid);
1288
vpe_getgid(int index)1289 int vpe_getgid(int index)
1290 {
1291 struct vpe *v;
1292
1293 if ((v = get_vpe(index)) == NULL)
1294 return -1;
1295
1296 return v->gid;
1297 }
1298
1299 EXPORT_SYMBOL(vpe_getgid);
1300
vpe_notify(int index,struct vpe_notifications * notify)1301 int vpe_notify(int index, struct vpe_notifications *notify)
1302 {
1303 struct vpe *v;
1304
1305 if ((v = get_vpe(index)) == NULL)
1306 return -1;
1307
1308 list_add(¬ify->list, &v->notify);
1309 return 0;
1310 }
1311
1312 EXPORT_SYMBOL(vpe_notify);
1313
vpe_getcwd(int index)1314 char *vpe_getcwd(int index)
1315 {
1316 struct vpe *v;
1317
1318 if ((v = get_vpe(index)) == NULL)
1319 return NULL;
1320
1321 return v->cwd;
1322 }
1323
1324 EXPORT_SYMBOL(vpe_getcwd);
1325
store_kill(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)1326 static ssize_t store_kill(struct device *dev, struct device_attribute *attr,
1327 const char *buf, size_t len)
1328 {
1329 struct vpe *vpe = get_vpe(tclimit);
1330 struct vpe_notifications *not;
1331
1332 list_for_each_entry(not, &vpe->notify, list) {
1333 not->stop(tclimit);
1334 }
1335
1336 release_progmem(vpe->load_addr);
1337 cleanup_tc(get_tc(tclimit));
1338 vpe_stop(vpe);
1339 vpe_free(vpe);
1340
1341 return len;
1342 }
1343
show_ntcs(struct device * cd,struct device_attribute * attr,char * buf)1344 static ssize_t show_ntcs(struct device *cd, struct device_attribute *attr,
1345 char *buf)
1346 {
1347 struct vpe *vpe = get_vpe(tclimit);
1348
1349 return sprintf(buf, "%d\n", vpe->ntcs);
1350 }
1351
store_ntcs(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)1352 static ssize_t store_ntcs(struct device *dev, struct device_attribute *attr,
1353 const char *buf, size_t len)
1354 {
1355 struct vpe *vpe = get_vpe(tclimit);
1356 unsigned long new;
1357 char *endp;
1358
1359 new = simple_strtoul(buf, &endp, 0);
1360 if (endp == buf)
1361 goto out_einval;
1362
1363 if (new == 0 || new > (hw_tcs - tclimit))
1364 goto out_einval;
1365
1366 vpe->ntcs = new;
1367
1368 return len;
1369
1370 out_einval:
1371 return -EINVAL;
1372 }
1373
1374 static struct device_attribute vpe_class_attributes[] = {
1375 __ATTR(kill, S_IWUSR, NULL, store_kill),
1376 __ATTR(ntcs, S_IRUGO | S_IWUSR, show_ntcs, store_ntcs),
1377 {}
1378 };
1379
vpe_device_release(struct device * cd)1380 static void vpe_device_release(struct device *cd)
1381 {
1382 kfree(cd);
1383 }
1384
1385 struct class vpe_class = {
1386 .name = "vpe",
1387 .owner = THIS_MODULE,
1388 .dev_release = vpe_device_release,
1389 .dev_attrs = vpe_class_attributes,
1390 };
1391
1392 struct device vpe_device;
1393
vpe_module_init(void)1394 static int __init vpe_module_init(void)
1395 {
1396 unsigned int mtflags, vpflags;
1397 unsigned long flags, val;
1398 struct vpe *v = NULL;
1399 struct tc *t;
1400 int tc, err;
1401
1402 if (!cpu_has_mipsmt) {
1403 printk("VPE loader: not a MIPS MT capable processor\n");
1404 return -ENODEV;
1405 }
1406
1407 if (vpelimit == 0) {
1408 printk(KERN_WARNING "No VPEs reserved for AP/SP, not "
1409 "initializing VPE loader.\nPass maxvpes=<n> argument as "
1410 "kernel argument\n");
1411
1412 return -ENODEV;
1413 }
1414
1415 if (tclimit == 0) {
1416 printk(KERN_WARNING "No TCs reserved for AP/SP, not "
1417 "initializing VPE loader.\nPass maxtcs=<n> argument as "
1418 "kernel argument\n");
1419
1420 return -ENODEV;
1421 }
1422
1423 major = register_chrdev(0, module_name, &vpe_fops);
1424 if (major < 0) {
1425 printk("VPE loader: unable to register character device\n");
1426 return major;
1427 }
1428
1429 err = class_register(&vpe_class);
1430 if (err) {
1431 printk(KERN_ERR "vpe_class registration failed\n");
1432 goto out_chrdev;
1433 }
1434
1435 device_initialize(&vpe_device);
1436 vpe_device.class = &vpe_class,
1437 vpe_device.parent = NULL,
1438 dev_set_name(&vpe_device, "vpe1");
1439 vpe_device.devt = MKDEV(major, minor);
1440 err = device_add(&vpe_device);
1441 if (err) {
1442 printk(KERN_ERR "Adding vpe_device failed\n");
1443 goto out_class;
1444 }
1445
1446 local_irq_save(flags);
1447 mtflags = dmt();
1448 vpflags = dvpe();
1449
1450 /* Put MVPE's into 'configuration state' */
1451 set_c0_mvpcontrol(MVPCONTROL_VPC);
1452
1453 /* dump_mtregs(); */
1454
1455 val = read_c0_mvpconf0();
1456 hw_tcs = (val & MVPCONF0_PTC) + 1;
1457 hw_vpes = ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
1458
1459 for (tc = tclimit; tc < hw_tcs; tc++) {
1460 /*
1461 * Must re-enable multithreading temporarily or in case we
1462 * reschedule send IPIs or similar we might hang.
1463 */
1464 clear_c0_mvpcontrol(MVPCONTROL_VPC);
1465 evpe(vpflags);
1466 emt(mtflags);
1467 local_irq_restore(flags);
1468 t = alloc_tc(tc);
1469 if (!t) {
1470 err = -ENOMEM;
1471 goto out;
1472 }
1473
1474 local_irq_save(flags);
1475 mtflags = dmt();
1476 vpflags = dvpe();
1477 set_c0_mvpcontrol(MVPCONTROL_VPC);
1478
1479 /* VPE's */
1480 if (tc < hw_tcs) {
1481 settc(tc);
1482
1483 if ((v = alloc_vpe(tc)) == NULL) {
1484 printk(KERN_WARNING "VPE: unable to allocate VPE\n");
1485
1486 goto out_reenable;
1487 }
1488
1489 v->ntcs = hw_tcs - tclimit;
1490
1491 /* add the tc to the list of this vpe's tc's. */
1492 list_add(&t->tc, &v->tc);
1493
1494 /* deactivate all but vpe0 */
1495 if (tc >= tclimit) {
1496 unsigned long tmp = read_vpe_c0_vpeconf0();
1497
1498 tmp &= ~VPECONF0_VPA;
1499
1500 /* master VPE */
1501 tmp |= VPECONF0_MVP;
1502 write_vpe_c0_vpeconf0(tmp);
1503 }
1504
1505 /* disable multi-threading with TC's */
1506 write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE);
1507
1508 if (tc >= vpelimit) {
1509 /*
1510 * Set config to be the same as vpe0,
1511 * particularly kseg0 coherency alg
1512 */
1513 write_vpe_c0_config(read_c0_config());
1514 }
1515 }
1516
1517 /* TC's */
1518 t->pvpe = v; /* set the parent vpe */
1519
1520 if (tc >= tclimit) {
1521 unsigned long tmp;
1522
1523 settc(tc);
1524
1525 /* Any TC that is bound to VPE0 gets left as is - in case
1526 we are running SMTC on VPE0. A TC that is bound to any
1527 other VPE gets bound to VPE0, ideally I'd like to make
1528 it homeless but it doesn't appear to let me bind a TC
1529 to a non-existent VPE. Which is perfectly reasonable.
1530
1531 The (un)bound state is visible to an EJTAG probe so may
1532 notify GDB...
1533 */
1534
1535 if (((tmp = read_tc_c0_tcbind()) & TCBIND_CURVPE)) {
1536 /* tc is bound >vpe0 */
1537 write_tc_c0_tcbind(tmp & ~TCBIND_CURVPE);
1538
1539 t->pvpe = get_vpe(0); /* set the parent vpe */
1540 }
1541
1542 /* halt the TC */
1543 write_tc_c0_tchalt(TCHALT_H);
1544 mips_ihb();
1545
1546 tmp = read_tc_c0_tcstatus();
1547
1548 /* mark not activated and not dynamically allocatable */
1549 tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1550 tmp |= TCSTATUS_IXMT; /* interrupt exempt */
1551 write_tc_c0_tcstatus(tmp);
1552 }
1553 }
1554
1555 out_reenable:
1556 /* release config state */
1557 clear_c0_mvpcontrol(MVPCONTROL_VPC);
1558
1559 evpe(vpflags);
1560 emt(mtflags);
1561 local_irq_restore(flags);
1562
1563 return 0;
1564
1565 out_class:
1566 class_unregister(&vpe_class);
1567 out_chrdev:
1568 unregister_chrdev(major, module_name);
1569
1570 out:
1571 return err;
1572 }
1573
vpe_module_exit(void)1574 static void __exit vpe_module_exit(void)
1575 {
1576 struct vpe *v, *n;
1577
1578 device_del(&vpe_device);
1579 unregister_chrdev(major, module_name);
1580
1581 /* No locking needed here */
1582 list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list) {
1583 if (v->state != VPE_STATE_UNUSED)
1584 release_vpe(v);
1585 }
1586 }
1587
1588 module_init(vpe_module_init);
1589 module_exit(vpe_module_exit);
1590 MODULE_DESCRIPTION("MIPS VPE Loader");
1591 MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
1592 MODULE_LICENSE("GPL");
1593