Linux 2.6.25-rc4
[linux-2.6/next.git] / arch / mips / kernel / vpe.c
blobeed2dc4273e08a47af6472533ce9f77dea7b5e2d
1 /*
2 * Copyright (C) 2004, 2005 MIPS Technologies, Inc. All rights reserved.
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.
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.
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.
19 * VPE support module
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.
27 * To load and run, simply cat a SP 'program file' to /dev/vpe1.
28 * i.e cat spapp >/dev/vpe1.
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>
57 typedef void *vpe_handle;
59 #ifndef ARCH_SHF_SMALL
60 #define ARCH_SHF_SMALL 0
61 #endif
63 /* If this is set, the section belongs in the init part of the module */
64 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
67 * The number of TCs and VPEs physically available on the core
69 static int hw_tcs, hw_vpes;
70 static char module_name[] = "vpe";
71 static int major;
72 static const int minor = 1; /* fixed for now */
74 #ifdef CONFIG_MIPS_APSP_KSPD
75 static struct kspd_notifications kspd_events;
76 static int kspd_events_reqd = 0;
77 #endif
79 /* grab the likely amount of memory we will need. */
80 #ifdef CONFIG_MIPS_VPE_LOADER_TOM
81 #define P_SIZE (2 * 1024 * 1024)
82 #else
83 /* add an overhead to the max kmalloc size for non-striped symbols/etc */
84 #define P_SIZE (256 * 1024)
85 #endif
87 extern unsigned long physical_memsize;
89 #define MAX_VPES 16
90 #define VPE_PATH_MAX 256
92 enum vpe_state {
93 VPE_STATE_UNUSED = 0,
94 VPE_STATE_INUSE,
95 VPE_STATE_RUNNING
98 enum tc_state {
99 TC_STATE_UNUSED = 0,
100 TC_STATE_INUSE,
101 TC_STATE_RUNNING,
102 TC_STATE_DYNAMIC
105 struct vpe {
106 enum vpe_state state;
108 /* (device) minor associated with this vpe */
109 int minor;
111 /* elfloader stuff */
112 void *load_addr;
113 unsigned long len;
114 char *pbuffer;
115 unsigned long plen;
116 unsigned int uid, gid;
117 char cwd[VPE_PATH_MAX];
119 unsigned long __start;
121 /* tc's associated with this vpe */
122 struct list_head tc;
124 /* The list of vpe's */
125 struct list_head list;
127 /* shared symbol address */
128 void *shared_ptr;
130 /* the list of who wants to know when something major happens */
131 struct list_head notify;
133 unsigned int ntcs;
136 struct tc {
137 enum tc_state state;
138 int index;
140 struct vpe *pvpe; /* parent VPE */
141 struct list_head tc; /* The list of TC's with this VPE */
142 struct list_head list; /* The global list of tc's */
145 struct {
146 /* Virtual processing elements */
147 struct list_head vpe_list;
149 /* Thread contexts */
150 struct list_head tc_list;
151 } vpecontrol = {
152 .vpe_list = LIST_HEAD_INIT(vpecontrol.vpe_list),
153 .tc_list = LIST_HEAD_INIT(vpecontrol.tc_list)
156 static void release_progmem(void *ptr);
157 extern void save_gp_address(unsigned int secbase, unsigned int rel);
159 /* get the vpe associated with this minor */
160 struct vpe *get_vpe(int minor)
162 struct vpe *v;
164 if (!cpu_has_mipsmt)
165 return NULL;
167 list_for_each_entry(v, &vpecontrol.vpe_list, list) {
168 if (v->minor == minor)
169 return v;
172 return NULL;
175 /* get the vpe associated with this minor */
176 struct tc *get_tc(int index)
178 struct tc *t;
180 list_for_each_entry(t, &vpecontrol.tc_list, list) {
181 if (t->index == index)
182 return t;
185 return NULL;
188 struct tc *get_tc_unused(void)
190 struct tc *t;
192 list_for_each_entry(t, &vpecontrol.tc_list, list) {
193 if (t->state == TC_STATE_UNUSED)
194 return t;
197 return NULL;
200 /* allocate a vpe and associate it with this minor (or index) */
201 struct vpe *alloc_vpe(int minor)
203 struct vpe *v;
205 if ((v = kzalloc(sizeof(struct vpe), GFP_KERNEL)) == NULL) {
206 return NULL;
209 INIT_LIST_HEAD(&v->tc);
210 list_add_tail(&v->list, &vpecontrol.vpe_list);
212 INIT_LIST_HEAD(&v->notify);
213 v->minor = minor;
214 return v;
217 /* allocate a tc. At startup only tc0 is running, all other can be halted. */
218 struct tc *alloc_tc(int index)
220 struct tc *tc;
222 if ((tc = kzalloc(sizeof(struct tc), GFP_KERNEL)) == NULL)
223 goto out;
225 INIT_LIST_HEAD(&tc->tc);
226 tc->index = index;
227 list_add_tail(&tc->list, &vpecontrol.tc_list);
229 out:
230 return tc;
233 /* clean up and free everything */
234 void release_vpe(struct vpe *v)
236 list_del(&v->list);
237 if (v->load_addr)
238 release_progmem(v);
239 kfree(v);
242 void dump_mtregs(void)
244 unsigned long val;
246 val = read_c0_config3();
247 printk("config3 0x%lx MT %ld\n", val,
248 (val & CONFIG3_MT) >> CONFIG3_MT_SHIFT);
250 val = read_c0_mvpcontrol();
251 printk("MVPControl 0x%lx, STLB %ld VPC %ld EVP %ld\n", val,
252 (val & MVPCONTROL_STLB) >> MVPCONTROL_STLB_SHIFT,
253 (val & MVPCONTROL_VPC) >> MVPCONTROL_VPC_SHIFT,
254 (val & MVPCONTROL_EVP));
256 val = read_c0_mvpconf0();
257 printk("mvpconf0 0x%lx, PVPE %ld PTC %ld M %ld\n", val,
258 (val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT,
259 val & MVPCONF0_PTC, (val & MVPCONF0_M) >> MVPCONF0_M_SHIFT);
262 /* Find some VPE program space */
263 static void *alloc_progmem(unsigned long len)
265 #ifdef CONFIG_MIPS_VPE_LOADER_TOM
266 /* this means you must tell linux to use less memory than you physically have */
267 return pfn_to_kaddr(max_pfn);
268 #else
269 // simple grab some mem for now
270 return kmalloc(len, GFP_KERNEL);
271 #endif
274 static void release_progmem(void *ptr)
276 #ifndef CONFIG_MIPS_VPE_LOADER_TOM
277 kfree(ptr);
278 #endif
281 /* Update size with this section: return offset. */
282 static long get_offset(unsigned long *size, Elf_Shdr * sechdr)
284 long ret;
286 ret = ALIGN(*size, sechdr->sh_addralign ? : 1);
287 *size = ret + sechdr->sh_size;
288 return ret;
291 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
292 might -- code, read-only data, read-write data, small data. Tally
293 sizes, and place the offsets into sh_entsize fields: high bit means it
294 belongs in init. */
295 static void layout_sections(struct module *mod, const Elf_Ehdr * hdr,
296 Elf_Shdr * sechdrs, const char *secstrings)
298 static unsigned long const masks[][2] = {
299 /* NOTE: all executable code must be the first section
300 * in this array; otherwise modify the text_size
301 * finder in the two loops below */
302 {SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL},
303 {SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL},
304 {SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL},
305 {ARCH_SHF_SMALL | SHF_ALLOC, 0}
307 unsigned int m, i;
309 for (i = 0; i < hdr->e_shnum; i++)
310 sechdrs[i].sh_entsize = ~0UL;
312 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
313 for (i = 0; i < hdr->e_shnum; ++i) {
314 Elf_Shdr *s = &sechdrs[i];
316 // || strncmp(secstrings + s->sh_name, ".init", 5) == 0)
317 if ((s->sh_flags & masks[m][0]) != masks[m][0]
318 || (s->sh_flags & masks[m][1])
319 || s->sh_entsize != ~0UL)
320 continue;
321 s->sh_entsize = get_offset(&mod->core_size, s);
324 if (m == 0)
325 mod->core_text_size = mod->core_size;
331 /* from module-elf32.c, but subverted a little */
333 struct mips_hi16 {
334 struct mips_hi16 *next;
335 Elf32_Addr *addr;
336 Elf32_Addr value;
339 static struct mips_hi16 *mips_hi16_list;
340 static unsigned int gp_offs, gp_addr;
342 static int apply_r_mips_none(struct module *me, uint32_t *location,
343 Elf32_Addr v)
345 return 0;
348 static int apply_r_mips_gprel16(struct module *me, uint32_t *location,
349 Elf32_Addr v)
351 int rel;
353 if( !(*location & 0xffff) ) {
354 rel = (int)v - gp_addr;
356 else {
357 /* .sbss + gp(relative) + offset */
358 /* kludge! */
359 rel = (int)(short)((int)v + gp_offs +
360 (int)(short)(*location & 0xffff) - gp_addr);
363 if( (rel > 32768) || (rel < -32768) ) {
364 printk(KERN_DEBUG "VPE loader: apply_r_mips_gprel16: "
365 "relative address 0x%x out of range of gp register\n",
366 rel);
367 return -ENOEXEC;
370 *location = (*location & 0xffff0000) | (rel & 0xffff);
372 return 0;
375 static int apply_r_mips_pc16(struct module *me, uint32_t *location,
376 Elf32_Addr v)
378 int rel;
379 rel = (((unsigned int)v - (unsigned int)location));
380 rel >>= 2; // because the offset is in _instructions_ not bytes.
381 rel -= 1; // and one instruction less due to the branch delay slot.
383 if( (rel > 32768) || (rel < -32768) ) {
384 printk(KERN_DEBUG "VPE loader: "
385 "apply_r_mips_pc16: relative address out of range 0x%x\n", rel);
386 return -ENOEXEC;
389 *location = (*location & 0xffff0000) | (rel & 0xffff);
391 return 0;
394 static int apply_r_mips_32(struct module *me, uint32_t *location,
395 Elf32_Addr v)
397 *location += v;
399 return 0;
402 static int apply_r_mips_26(struct module *me, uint32_t *location,
403 Elf32_Addr v)
405 if (v % 4) {
406 printk(KERN_DEBUG "VPE loader: apply_r_mips_26 "
407 " unaligned relocation\n");
408 return -ENOEXEC;
412 * Not desperately convinced this is a good check of an overflow condition
413 * anyway. But it gets in the way of handling undefined weak symbols which
414 * we want to set to zero.
415 * if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
416 * printk(KERN_ERR
417 * "module %s: relocation overflow\n",
418 * me->name);
419 * return -ENOEXEC;
423 *location = (*location & ~0x03ffffff) |
424 ((*location + (v >> 2)) & 0x03ffffff);
425 return 0;
428 static int apply_r_mips_hi16(struct module *me, uint32_t *location,
429 Elf32_Addr v)
431 struct mips_hi16 *n;
434 * We cannot relocate this one now because we don't know the value of
435 * the carry we need to add. Save the information, and let LO16 do the
436 * actual relocation.
438 n = kmalloc(sizeof *n, GFP_KERNEL);
439 if (!n)
440 return -ENOMEM;
442 n->addr = location;
443 n->value = v;
444 n->next = mips_hi16_list;
445 mips_hi16_list = n;
447 return 0;
450 static int apply_r_mips_lo16(struct module *me, uint32_t *location,
451 Elf32_Addr v)
453 unsigned long insnlo = *location;
454 Elf32_Addr val, vallo;
456 /* Sign extend the addend we extract from the lo insn. */
457 vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
459 if (mips_hi16_list != NULL) {
460 struct mips_hi16 *l;
462 l = mips_hi16_list;
463 while (l != NULL) {
464 struct mips_hi16 *next;
465 unsigned long insn;
468 * The value for the HI16 had best be the same.
470 if (v != l->value) {
471 printk(KERN_DEBUG "VPE loader: "
472 "apply_r_mips_lo16/hi16: \t"
473 "inconsistent value information\n");
474 return -ENOEXEC;
478 * Do the HI16 relocation. Note that we actually don't
479 * need to know anything about the LO16 itself, except
480 * where to find the low 16 bits of the addend needed
481 * by the LO16.
483 insn = *l->addr;
484 val = ((insn & 0xffff) << 16) + vallo;
485 val += v;
488 * Account for the sign extension that will happen in
489 * the low bits.
491 val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
493 insn = (insn & ~0xffff) | val;
494 *l->addr = insn;
496 next = l->next;
497 kfree(l);
498 l = next;
501 mips_hi16_list = NULL;
505 * Ok, we're done with the HI16 relocs. Now deal with the LO16.
507 val = v + vallo;
508 insnlo = (insnlo & ~0xffff) | (val & 0xffff);
509 *location = insnlo;
511 return 0;
514 static int (*reloc_handlers[]) (struct module *me, uint32_t *location,
515 Elf32_Addr v) = {
516 [R_MIPS_NONE] = apply_r_mips_none,
517 [R_MIPS_32] = apply_r_mips_32,
518 [R_MIPS_26] = apply_r_mips_26,
519 [R_MIPS_HI16] = apply_r_mips_hi16,
520 [R_MIPS_LO16] = apply_r_mips_lo16,
521 [R_MIPS_GPREL16] = apply_r_mips_gprel16,
522 [R_MIPS_PC16] = apply_r_mips_pc16
525 static char *rstrs[] = {
526 [R_MIPS_NONE] = "MIPS_NONE",
527 [R_MIPS_32] = "MIPS_32",
528 [R_MIPS_26] = "MIPS_26",
529 [R_MIPS_HI16] = "MIPS_HI16",
530 [R_MIPS_LO16] = "MIPS_LO16",
531 [R_MIPS_GPREL16] = "MIPS_GPREL16",
532 [R_MIPS_PC16] = "MIPS_PC16"
535 int apply_relocations(Elf32_Shdr *sechdrs,
536 const char *strtab,
537 unsigned int symindex,
538 unsigned int relsec,
539 struct module *me)
541 Elf32_Rel *rel = (void *) sechdrs[relsec].sh_addr;
542 Elf32_Sym *sym;
543 uint32_t *location;
544 unsigned int i;
545 Elf32_Addr v;
546 int res;
548 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
549 Elf32_Word r_info = rel[i].r_info;
551 /* This is where to make the change */
552 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
553 + rel[i].r_offset;
554 /* This is the symbol it is referring to */
555 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
556 + ELF32_R_SYM(r_info);
558 if (!sym->st_value) {
559 printk(KERN_DEBUG "%s: undefined weak symbol %s\n",
560 me->name, strtab + sym->st_name);
561 /* just print the warning, dont barf */
564 v = sym->st_value;
566 res = reloc_handlers[ELF32_R_TYPE(r_info)](me, location, v);
567 if( res ) {
568 char *r = rstrs[ELF32_R_TYPE(r_info)];
569 printk(KERN_WARNING "VPE loader: .text+0x%x "
570 "relocation type %s for symbol \"%s\" failed\n",
571 rel[i].r_offset, r ? r : "UNKNOWN",
572 strtab + sym->st_name);
573 return res;
577 return 0;
580 void save_gp_address(unsigned int secbase, unsigned int rel)
582 gp_addr = secbase + rel;
583 gp_offs = gp_addr - (secbase & 0xffff0000);
585 /* end module-elf32.c */
589 /* Change all symbols so that sh_value encodes the pointer directly. */
590 static void simplify_symbols(Elf_Shdr * sechdrs,
591 unsigned int symindex,
592 const char *strtab,
593 const char *secstrings,
594 unsigned int nsecs, struct module *mod)
596 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
597 unsigned long secbase, bssbase = 0;
598 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
599 int size;
601 /* find the .bss section for COMMON symbols */
602 for (i = 0; i < nsecs; i++) {
603 if (strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) == 0) {
604 bssbase = sechdrs[i].sh_addr;
605 break;
609 for (i = 1; i < n; i++) {
610 switch (sym[i].st_shndx) {
611 case SHN_COMMON:
612 /* Allocate space for the symbol in the .bss section.
613 st_value is currently size.
614 We want it to have the address of the symbol. */
616 size = sym[i].st_value;
617 sym[i].st_value = bssbase;
619 bssbase += size;
620 break;
622 case SHN_ABS:
623 /* Don't need to do anything */
624 break;
626 case SHN_UNDEF:
627 /* ret = -ENOENT; */
628 break;
630 case SHN_MIPS_SCOMMON:
631 printk(KERN_DEBUG "simplify_symbols: ignoring SHN_MIPS_SCOMMON "
632 "symbol <%s> st_shndx %d\n", strtab + sym[i].st_name,
633 sym[i].st_shndx);
634 // .sbss section
635 break;
637 default:
638 secbase = sechdrs[sym[i].st_shndx].sh_addr;
640 if (strncmp(strtab + sym[i].st_name, "_gp", 3) == 0) {
641 save_gp_address(secbase, sym[i].st_value);
644 sym[i].st_value += secbase;
645 break;
650 #ifdef DEBUG_ELFLOADER
651 static void dump_elfsymbols(Elf_Shdr * sechdrs, unsigned int symindex,
652 const char *strtab, struct module *mod)
654 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
655 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
657 printk(KERN_DEBUG "dump_elfsymbols: n %d\n", n);
658 for (i = 1; i < n; i++) {
659 printk(KERN_DEBUG " i %d name <%s> 0x%x\n", i,
660 strtab + sym[i].st_name, sym[i].st_value);
663 #endif
665 /* We are prepared so configure and start the VPE... */
666 static int vpe_run(struct vpe * v)
668 unsigned long flags, val, dmt_flag;
669 struct vpe_notifications *n;
670 unsigned int vpeflags;
671 struct tc *t;
673 /* check we are the Master VPE */
674 local_irq_save(flags);
675 val = read_c0_vpeconf0();
676 if (!(val & VPECONF0_MVP)) {
677 printk(KERN_WARNING
678 "VPE loader: only Master VPE's are allowed to configure MT\n");
679 local_irq_restore(flags);
681 return -1;
684 dmt_flag = dmt();
685 vpeflags = dvpe();
687 if (!list_empty(&v->tc)) {
688 if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
689 evpe(vpeflags);
690 emt(dmt_flag);
691 local_irq_restore(flags);
693 printk(KERN_WARNING
694 "VPE loader: TC %d is already in use.\n",
695 t->index);
696 return -ENOEXEC;
698 } else {
699 evpe(vpeflags);
700 emt(dmt_flag);
701 local_irq_restore(flags);
703 printk(KERN_WARNING
704 "VPE loader: No TC's associated with VPE %d\n",
705 v->minor);
707 return -ENOEXEC;
710 /* Put MVPE's into 'configuration state' */
711 set_c0_mvpcontrol(MVPCONTROL_VPC);
713 settc(t->index);
715 /* should check it is halted, and not activated */
716 if ((read_tc_c0_tcstatus() & TCSTATUS_A) || !(read_tc_c0_tchalt() & TCHALT_H)) {
717 evpe(vpeflags);
718 emt(dmt_flag);
719 local_irq_restore(flags);
721 printk(KERN_WARNING "VPE loader: TC %d is already active!\n",
722 t->index);
724 return -ENOEXEC;
727 /* Write the address we want it to start running from in the TCPC register. */
728 write_tc_c0_tcrestart((unsigned long)v->__start);
729 write_tc_c0_tccontext((unsigned long)0);
732 * Mark the TC as activated, not interrupt exempt and not dynamically
733 * allocatable
735 val = read_tc_c0_tcstatus();
736 val = (val & ~(TCSTATUS_DA | TCSTATUS_IXMT)) | TCSTATUS_A;
737 write_tc_c0_tcstatus(val);
739 write_tc_c0_tchalt(read_tc_c0_tchalt() & ~TCHALT_H);
742 * The sde-kit passes 'memsize' to __start in $a3, so set something
743 * here... Or set $a3 to zero and define DFLT_STACK_SIZE and
744 * DFLT_HEAP_SIZE when you compile your program
746 mttgpr(6, v->ntcs);
747 mttgpr(7, physical_memsize);
749 /* set up VPE1 */
751 * bind the TC to VPE 1 as late as possible so we only have the final
752 * VPE registers to set up, and so an EJTAG probe can trigger on it
754 write_tc_c0_tcbind((read_tc_c0_tcbind() & ~TCBIND_CURVPE) | 1);
756 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~(VPECONF0_VPA));
758 back_to_back_c0_hazard();
760 /* Set up the XTC bit in vpeconf0 to point at our tc */
761 write_vpe_c0_vpeconf0( (read_vpe_c0_vpeconf0() & ~(VPECONF0_XTC))
762 | (t->index << VPECONF0_XTC_SHIFT));
764 back_to_back_c0_hazard();
766 /* enable this VPE */
767 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA);
769 /* clear out any left overs from a previous program */
770 write_vpe_c0_status(0);
771 write_vpe_c0_cause(0);
773 /* take system out of configuration state */
774 clear_c0_mvpcontrol(MVPCONTROL_VPC);
776 #ifdef CONFIG_SMP
777 evpe(EVPE_ENABLE);
778 #else
779 evpe(vpeflags);
780 #endif
781 emt(dmt_flag);
782 local_irq_restore(flags);
784 list_for_each_entry(n, &v->notify, list)
785 n->start(minor);
787 return 0;
790 static int find_vpe_symbols(struct vpe * v, Elf_Shdr * sechdrs,
791 unsigned int symindex, const char *strtab,
792 struct module *mod)
794 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
795 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
797 for (i = 1; i < n; i++) {
798 if (strcmp(strtab + sym[i].st_name, "__start") == 0) {
799 v->__start = sym[i].st_value;
802 if (strcmp(strtab + sym[i].st_name, "vpe_shared") == 0) {
803 v->shared_ptr = (void *)sym[i].st_value;
807 if ( (v->__start == 0) || (v->shared_ptr == NULL))
808 return -1;
810 return 0;
814 * Allocates a VPE with some program code space(the load address), copies the
815 * contents of the program (p)buffer performing relocatations/etc, free's it
816 * when finished.
818 static int vpe_elfload(struct vpe * v)
820 Elf_Ehdr *hdr;
821 Elf_Shdr *sechdrs;
822 long err = 0;
823 char *secstrings, *strtab = NULL;
824 unsigned int len, i, symindex = 0, strindex = 0, relocate = 0;
825 struct module mod; // so we can re-use the relocations code
827 memset(&mod, 0, sizeof(struct module));
828 strcpy(mod.name, "VPE loader");
830 hdr = (Elf_Ehdr *) v->pbuffer;
831 len = v->plen;
833 /* Sanity checks against insmoding binaries or wrong arch,
834 weird elf version */
835 if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
836 || (hdr->e_type != ET_REL && hdr->e_type != ET_EXEC)
837 || !elf_check_arch(hdr)
838 || hdr->e_shentsize != sizeof(*sechdrs)) {
839 printk(KERN_WARNING
840 "VPE loader: program wrong arch or weird elf version\n");
842 return -ENOEXEC;
845 if (hdr->e_type == ET_REL)
846 relocate = 1;
848 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
849 printk(KERN_ERR "VPE loader: program length %u truncated\n",
850 len);
852 return -ENOEXEC;
855 /* Convenience variables */
856 sechdrs = (void *)hdr + hdr->e_shoff;
857 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
858 sechdrs[0].sh_addr = 0;
860 /* And these should exist, but gcc whinges if we don't init them */
861 symindex = strindex = 0;
863 if (relocate) {
864 for (i = 1; i < hdr->e_shnum; i++) {
865 if (sechdrs[i].sh_type != SHT_NOBITS
866 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) {
867 printk(KERN_ERR "VPE program length %u truncated\n",
868 len);
869 return -ENOEXEC;
872 /* Mark all sections sh_addr with their address in the
873 temporary image. */
874 sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
876 /* Internal symbols and strings. */
877 if (sechdrs[i].sh_type == SHT_SYMTAB) {
878 symindex = i;
879 strindex = sechdrs[i].sh_link;
880 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
883 layout_sections(&mod, hdr, sechdrs, secstrings);
886 v->load_addr = alloc_progmem(mod.core_size);
887 memset(v->load_addr, 0, mod.core_size);
889 printk("VPE loader: loading to %p\n", v->load_addr);
891 if (relocate) {
892 for (i = 0; i < hdr->e_shnum; i++) {
893 void *dest;
895 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
896 continue;
898 dest = v->load_addr + sechdrs[i].sh_entsize;
900 if (sechdrs[i].sh_type != SHT_NOBITS)
901 memcpy(dest, (void *)sechdrs[i].sh_addr,
902 sechdrs[i].sh_size);
903 /* Update sh_addr to point to copy in image. */
904 sechdrs[i].sh_addr = (unsigned long)dest;
906 printk(KERN_DEBUG " section sh_name %s sh_addr 0x%x\n",
907 secstrings + sechdrs[i].sh_name, sechdrs[i].sh_addr);
910 /* Fix up syms, so that st_value is a pointer to location. */
911 simplify_symbols(sechdrs, symindex, strtab, secstrings,
912 hdr->e_shnum, &mod);
914 /* Now do relocations. */
915 for (i = 1; i < hdr->e_shnum; i++) {
916 const char *strtab = (char *)sechdrs[strindex].sh_addr;
917 unsigned int info = sechdrs[i].sh_info;
919 /* Not a valid relocation section? */
920 if (info >= hdr->e_shnum)
921 continue;
923 /* Don't bother with non-allocated sections */
924 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
925 continue;
927 if (sechdrs[i].sh_type == SHT_REL)
928 err = apply_relocations(sechdrs, strtab, symindex, i,
929 &mod);
930 else if (sechdrs[i].sh_type == SHT_RELA)
931 err = apply_relocate_add(sechdrs, strtab, symindex, i,
932 &mod);
933 if (err < 0)
934 return err;
937 } else {
938 struct elf_phdr *phdr = (struct elf_phdr *) ((char *)hdr + hdr->e_phoff);
940 for (i = 0; i < hdr->e_phnum; i++) {
941 if (phdr->p_type != PT_LOAD)
942 continue;
944 memcpy((void *)phdr->p_paddr, (char *)hdr + phdr->p_offset, phdr->p_filesz);
945 memset((void *)phdr->p_paddr + phdr->p_filesz, 0, phdr->p_memsz - phdr->p_filesz);
946 phdr++;
949 for (i = 0; i < hdr->e_shnum; i++) {
950 /* Internal symbols and strings. */
951 if (sechdrs[i].sh_type == SHT_SYMTAB) {
952 symindex = i;
953 strindex = sechdrs[i].sh_link;
954 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
956 /* mark the symtab's address for when we try to find the
957 magic symbols */
958 sechdrs[i].sh_addr = (size_t) hdr + sechdrs[i].sh_offset;
963 /* make sure it's physically written out */
964 flush_icache_range((unsigned long)v->load_addr,
965 (unsigned long)v->load_addr + v->len);
967 if ((find_vpe_symbols(v, sechdrs, symindex, strtab, &mod)) < 0) {
968 if (v->__start == 0) {
969 printk(KERN_WARNING "VPE loader: program does not contain "
970 "a __start symbol\n");
971 return -ENOEXEC;
974 if (v->shared_ptr == NULL)
975 printk(KERN_WARNING "VPE loader: "
976 "program does not contain vpe_shared symbol.\n"
977 " Unable to use AMVP (AP/SP) facilities.\n");
980 printk(" elf loaded\n");
981 return 0;
984 static void cleanup_tc(struct tc *tc)
986 unsigned long flags;
987 unsigned int mtflags, vpflags;
988 int tmp;
990 local_irq_save(flags);
991 mtflags = dmt();
992 vpflags = dvpe();
993 /* Put MVPE's into 'configuration state' */
994 set_c0_mvpcontrol(MVPCONTROL_VPC);
996 settc(tc->index);
997 tmp = read_tc_c0_tcstatus();
999 /* mark not allocated and not dynamically allocatable */
1000 tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1001 tmp |= TCSTATUS_IXMT; /* interrupt exempt */
1002 write_tc_c0_tcstatus(tmp);
1004 write_tc_c0_tchalt(TCHALT_H);
1005 mips_ihb();
1007 /* bind it to anything other than VPE1 */
1008 // write_tc_c0_tcbind(read_tc_c0_tcbind() & ~TCBIND_CURVPE); // | TCBIND_CURVPE
1010 clear_c0_mvpcontrol(MVPCONTROL_VPC);
1011 evpe(vpflags);
1012 emt(mtflags);
1013 local_irq_restore(flags);
1016 static int getcwd(char *buff, int size)
1018 mm_segment_t old_fs;
1019 int ret;
1021 old_fs = get_fs();
1022 set_fs(KERNEL_DS);
1024 ret = sys_getcwd(buff, size);
1026 set_fs(old_fs);
1028 return ret;
1031 /* checks VPE is unused and gets ready to load program */
1032 static int vpe_open(struct inode *inode, struct file *filp)
1034 enum vpe_state state;
1035 struct vpe_notifications *not;
1036 struct vpe *v;
1037 int ret;
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;
1045 if ((v = get_vpe(tclimit)) == NULL) {
1046 printk(KERN_WARNING "VPE loader: unable to get vpe\n");
1047 return -ENODEV;
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");
1054 list_for_each_entry(not, &v->notify, list) {
1055 not->stop(tclimit);
1058 release_progmem(v->load_addr);
1059 cleanup_tc(get_tc(tclimit));
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;
1068 v->uid = filp->f_uid;
1069 v->gid = filp->f_gid;
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++;
1077 #endif
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);
1084 v->shared_ptr = NULL;
1085 v->__start = 0;
1087 return 0;
1090 static int vpe_release(struct inode *inode, struct file *filp)
1092 struct vpe *v;
1093 Elf_Ehdr *hdr;
1094 int ret = 0;
1096 v = get_vpe(tclimit);
1097 if (v == NULL)
1098 return -ENODEV;
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;
1108 } else {
1109 printk(KERN_WARNING "VPE loader: only elf files are supported\n");
1110 ret = -ENOEXEC;
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;
1121 // cleanup any temp buffers
1122 if (v->pbuffer)
1123 vfree(v->pbuffer);
1124 v->plen = 0;
1125 return ret;
1128 static ssize_t vpe_write(struct file *file, const char __user * buffer,
1129 size_t count, loff_t * ppos)
1131 size_t ret = count;
1132 struct vpe *v;
1134 if (iminor(file->f_path.dentry->d_inode) != minor)
1135 return -ENODEV;
1137 v = get_vpe(tclimit);
1138 if (v == NULL)
1139 return -ENODEV;
1141 if (v->pbuffer == NULL) {
1142 printk(KERN_ERR "VPE loader: no buffer for program\n");
1143 return -ENOMEM;
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;
1152 count -= copy_from_user(v->pbuffer + v->len, buffer, count);
1153 if (!count)
1154 return -EFAULT;
1156 v->len += count;
1157 return ret;
1160 static const struct file_operations vpe_fops = {
1161 .owner = THIS_MODULE,
1162 .open = vpe_open,
1163 .release = vpe_release,
1164 .write = vpe_write
1167 /* module wrapper entry points */
1168 /* give me a vpe */
1169 vpe_handle vpe_alloc(void)
1171 int i;
1172 struct vpe *v;
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;
1181 return NULL;
1184 EXPORT_SYMBOL(vpe_alloc);
1186 /* start running from here */
1187 int vpe_start(vpe_handle vpe, unsigned long start)
1189 struct vpe *v = vpe;
1191 v->__start = start;
1192 return vpe_run(v);
1195 EXPORT_SYMBOL(vpe_start);
1197 /* halt it for now */
1198 int vpe_stop(vpe_handle vpe)
1200 struct vpe *v = vpe;
1201 struct tc *t;
1202 unsigned int evpe_flags;
1204 evpe_flags = dvpe();
1206 if ((t = list_entry(v->tc.next, struct tc, tc)) != NULL) {
1208 settc(t->index);
1209 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1212 evpe(evpe_flags);
1214 return 0;
1217 EXPORT_SYMBOL(vpe_stop);
1219 /* I've done with it thank you */
1220 int vpe_free(vpe_handle vpe)
1222 struct vpe *v = vpe;
1223 struct tc *t;
1224 unsigned int evpe_flags;
1226 if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
1227 return -ENOEXEC;
1230 evpe_flags = dvpe();
1232 /* Put MVPE's into 'configuration state' */
1233 set_c0_mvpcontrol(MVPCONTROL_VPC);
1235 settc(t->index);
1236 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
1238 /* halt the TC */
1239 write_tc_c0_tchalt(TCHALT_H);
1240 mips_ihb();
1242 /* mark the TC unallocated */
1243 write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A);
1245 v->state = VPE_STATE_UNUSED;
1247 clear_c0_mvpcontrol(MVPCONTROL_VPC);
1248 evpe(evpe_flags);
1250 return 0;
1253 EXPORT_SYMBOL(vpe_free);
1255 void *vpe_get_shared(int index)
1257 struct vpe *v;
1259 if ((v = get_vpe(index)) == NULL)
1260 return NULL;
1262 return v->shared_ptr;
1265 EXPORT_SYMBOL(vpe_get_shared);
1267 int vpe_getuid(int index)
1269 struct vpe *v;
1271 if ((v = get_vpe(index)) == NULL)
1272 return -1;
1274 return v->uid;
1277 EXPORT_SYMBOL(vpe_getuid);
1279 int vpe_getgid(int index)
1281 struct vpe *v;
1283 if ((v = get_vpe(index)) == NULL)
1284 return -1;
1286 return v->gid;
1289 EXPORT_SYMBOL(vpe_getgid);
1291 int vpe_notify(int index, struct vpe_notifications *notify)
1293 struct vpe *v;
1295 if ((v = get_vpe(index)) == NULL)
1296 return -1;
1298 list_add(&notify->list, &v->notify);
1299 return 0;
1302 EXPORT_SYMBOL(vpe_notify);
1304 char *vpe_getcwd(int index)
1306 struct vpe *v;
1308 if ((v = get_vpe(index)) == NULL)
1309 return NULL;
1311 return v->cwd;
1314 EXPORT_SYMBOL(vpe_getcwd);
1316 #ifdef CONFIG_MIPS_APSP_KSPD
1317 static void kspd_sp_exit( int sp_id)
1319 cleanup_tc(get_tc(sp_id));
1321 #endif
1323 static ssize_t store_kill(struct device *dev, struct device_attribute *attr,
1324 const char *buf, size_t len)
1326 struct vpe *vpe = get_vpe(tclimit);
1327 struct vpe_notifications *not;
1329 list_for_each_entry(not, &vpe->notify, list) {
1330 not->stop(tclimit);
1333 release_progmem(vpe->load_addr);
1334 cleanup_tc(get_tc(tclimit));
1335 vpe_stop(vpe);
1336 vpe_free(vpe);
1338 return len;
1341 static ssize_t show_ntcs(struct device *cd, struct device_attribute *attr,
1342 char *buf)
1344 struct vpe *vpe = get_vpe(tclimit);
1346 return sprintf(buf, "%d\n", vpe->ntcs);
1349 static ssize_t store_ntcs(struct device *dev, struct device_attribute *attr,
1350 const char *buf, size_t len)
1352 struct vpe *vpe = get_vpe(tclimit);
1353 unsigned long new;
1354 char *endp;
1356 new = simple_strtoul(buf, &endp, 0);
1357 if (endp == buf)
1358 goto out_einval;
1360 if (new == 0 || new > (hw_tcs - tclimit))
1361 goto out_einval;
1363 vpe->ntcs = new;
1365 return len;
1367 out_einval:
1368 return -EINVAL;;
1371 static struct device_attribute vpe_class_attributes[] = {
1372 __ATTR(kill, S_IWUSR, NULL, store_kill),
1373 __ATTR(ntcs, S_IRUGO | S_IWUSR, show_ntcs, store_ntcs),
1377 static void vpe_device_release(struct device *cd)
1379 kfree(cd);
1382 struct class vpe_class = {
1383 .name = "vpe",
1384 .owner = THIS_MODULE,
1385 .dev_release = vpe_device_release,
1386 .dev_attrs = vpe_class_attributes,
1389 struct device vpe_device;
1391 static int __init vpe_module_init(void)
1393 unsigned int mtflags, vpflags;
1394 unsigned long flags, val;
1395 struct vpe *v = NULL;
1396 struct tc *t;
1397 int tc, err;
1399 if (!cpu_has_mipsmt) {
1400 printk("VPE loader: not a MIPS MT capable processor\n");
1401 return -ENODEV;
1404 if (vpelimit == 0) {
1405 printk(KERN_WARNING "No VPEs reserved for AP/SP, not "
1406 "initializing VPE loader.\nPass maxvpes=<n> argument as "
1407 "kernel argument\n");
1409 return -ENODEV;
1412 if (tclimit == 0) {
1413 printk(KERN_WARNING "No TCs reserved for AP/SP, not "
1414 "initializing VPE loader.\nPass maxtcs=<n> argument as "
1415 "kernel argument\n");
1417 return -ENODEV;
1420 major = register_chrdev(0, module_name, &vpe_fops);
1421 if (major < 0) {
1422 printk("VPE loader: unable to register character device\n");
1423 return major;
1426 err = class_register(&vpe_class);
1427 if (err) {
1428 printk(KERN_ERR "vpe_class registration failed\n");
1429 goto out_chrdev;
1432 device_initialize(&vpe_device);
1433 vpe_device.class = &vpe_class,
1434 vpe_device.parent = NULL,
1435 strlcpy(vpe_device.bus_id, "vpe1", BUS_ID_SIZE);
1436 vpe_device.devt = MKDEV(major, minor);
1437 err = device_add(&vpe_device);
1438 if (err) {
1439 printk(KERN_ERR "Adding vpe_device failed\n");
1440 goto out_class;
1443 local_irq_save(flags);
1444 mtflags = dmt();
1445 vpflags = dvpe();
1447 /* Put MVPE's into 'configuration state' */
1448 set_c0_mvpcontrol(MVPCONTROL_VPC);
1450 /* dump_mtregs(); */
1452 val = read_c0_mvpconf0();
1453 hw_tcs = (val & MVPCONF0_PTC) + 1;
1454 hw_vpes = ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
1456 for (tc = tclimit; tc < hw_tcs; tc++) {
1458 * Must re-enable multithreading temporarily or in case we
1459 * reschedule send IPIs or similar we might hang.
1461 clear_c0_mvpcontrol(MVPCONTROL_VPC);
1462 evpe(vpflags);
1463 emt(mtflags);
1464 local_irq_restore(flags);
1465 t = alloc_tc(tc);
1466 if (!t) {
1467 err = -ENOMEM;
1468 goto out;
1471 local_irq_save(flags);
1472 mtflags = dmt();
1473 vpflags = dvpe();
1474 set_c0_mvpcontrol(MVPCONTROL_VPC);
1476 /* VPE's */
1477 if (tc < hw_tcs) {
1478 settc(tc);
1480 if ((v = alloc_vpe(tc)) == NULL) {
1481 printk(KERN_WARNING "VPE: unable to allocate VPE\n");
1483 goto out_reenable;
1486 v->ntcs = hw_tcs - tclimit;
1488 /* add the tc to the list of this vpe's tc's. */
1489 list_add(&t->tc, &v->tc);
1491 /* deactivate all but vpe0 */
1492 if (tc >= tclimit) {
1493 unsigned long tmp = read_vpe_c0_vpeconf0();
1495 tmp &= ~VPECONF0_VPA;
1497 /* master VPE */
1498 tmp |= VPECONF0_MVP;
1499 write_vpe_c0_vpeconf0(tmp);
1502 /* disable multi-threading with TC's */
1503 write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE);
1505 if (tc >= vpelimit) {
1507 * Set config to be the same as vpe0,
1508 * particularly kseg0 coherency alg
1510 write_vpe_c0_config(read_c0_config());
1514 /* TC's */
1515 t->pvpe = v; /* set the parent vpe */
1517 if (tc >= tclimit) {
1518 unsigned long tmp;
1520 settc(tc);
1522 /* Any TC that is bound to VPE0 gets left as is - in case
1523 we are running SMTC on VPE0. A TC that is bound to any
1524 other VPE gets bound to VPE0, ideally I'd like to make
1525 it homeless but it doesn't appear to let me bind a TC
1526 to a non-existent VPE. Which is perfectly reasonable.
1528 The (un)bound state is visible to an EJTAG probe so may
1529 notify GDB...
1532 if (((tmp = read_tc_c0_tcbind()) & TCBIND_CURVPE)) {
1533 /* tc is bound >vpe0 */
1534 write_tc_c0_tcbind(tmp & ~TCBIND_CURVPE);
1536 t->pvpe = get_vpe(0); /* set the parent vpe */
1539 /* halt the TC */
1540 write_tc_c0_tchalt(TCHALT_H);
1541 mips_ihb();
1543 tmp = read_tc_c0_tcstatus();
1545 /* mark not activated and not dynamically allocatable */
1546 tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
1547 tmp |= TCSTATUS_IXMT; /* interrupt exempt */
1548 write_tc_c0_tcstatus(tmp);
1552 out_reenable:
1553 /* release config state */
1554 clear_c0_mvpcontrol(MVPCONTROL_VPC);
1556 evpe(vpflags);
1557 emt(mtflags);
1558 local_irq_restore(flags);
1560 #ifdef CONFIG_MIPS_APSP_KSPD
1561 kspd_events.kspd_sp_exit = kspd_sp_exit;
1562 #endif
1563 return 0;
1565 out_class:
1566 class_unregister(&vpe_class);
1567 out_chrdev:
1568 unregister_chrdev(major, module_name);
1570 out:
1571 return err;
1574 static void __exit vpe_module_exit(void)
1576 struct vpe *v, *n;
1578 list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list) {
1579 if (v->state != VPE_STATE_UNUSED) {
1580 release_vpe(v);
1584 device_del(&vpe_device);
1585 unregister_chrdev(major, module_name);
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");