1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1994 - 2000 Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
9 * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
10 */
11 #include <linux/bug.h>
12 #include <linux/init.h>
13 #include <linux/export.h>
14 #include <linux/signal.h>
15 #include <linux/sched.h>
16 #include <linux/smp.h>
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/string.h>
20 #include <linux/types.h>
21 #include <linux/pagemap.h>
22 #include <linux/ptrace.h>
23 #include <linux/mman.h>
24 #include <linux/mm.h>
25 #include <linux/memblock.h>
26 #include <linux/highmem.h>
27 #include <linux/swap.h>
28 #include <linux/proc_fs.h>
29 #include <linux/pfn.h>
30 #include <linux/hardirq.h>
31 #include <linux/gfp.h>
32 #include <linux/kcore.h>
33 #include <linux/initrd.h>
34
35 #include <asm/bootinfo.h>
36 #include <asm/cachectl.h>
37 #include <asm/cpu.h>
38 #include <asm/dma.h>
39 #include <asm/maar.h>
40 #include <asm/mmu_context.h>
41 #include <asm/sections.h>
42 #include <asm/pgalloc.h>
43 #include <asm/tlb.h>
44 #include <asm/fixmap.h>
45
46 /*
47 * We have up to 8 empty zeroed pages so we can map one of the right colour
48 * when needed. This is necessary only on R4000 / R4400 SC and MC versions
49 * where we have to avoid VCED / VECI exceptions for good performance at
50 * any price. Since page is never written to after the initialization we
51 * don't have to care about aliases on other CPUs.
52 */
53 unsigned long empty_zero_page, zero_page_mask;
54 EXPORT_SYMBOL_GPL(empty_zero_page);
55 EXPORT_SYMBOL(zero_page_mask);
56
57 /*
58 * Not static inline because used by IP27 special magic initialization code
59 */
setup_zero_pages(void)60 void setup_zero_pages(void)
61 {
62 unsigned int order, i;
63 struct page *page;
64
65 if (cpu_has_vce)
66 order = 3;
67 else
68 order = 0;
69
70 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
71 if (!empty_zero_page)
72 panic("Oh boy, that early out of memory?");
73
74 page = virt_to_page((void *)empty_zero_page);
75 split_page(page, order);
76 for (i = 0; i < (1 << order); i++, page++)
77 mark_page_reserved(page);
78
79 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK;
80 }
81
__kmap_pgprot(struct page * page,unsigned long addr,pgprot_t prot)82 static void *__kmap_pgprot(struct page *page, unsigned long addr, pgprot_t prot)
83 {
84 enum fixed_addresses idx;
85 unsigned int old_mmid;
86 unsigned long vaddr, flags, entrylo;
87 unsigned long old_ctx;
88 pte_t pte;
89 int tlbidx;
90
91 BUG_ON(Page_dcache_dirty(page));
92
93 preempt_disable();
94 pagefault_disable();
95 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
96 idx += in_interrupt() ? FIX_N_COLOURS : 0;
97 vaddr = __fix_to_virt(FIX_CMAP_END - idx);
98 pte = mk_pte(page, prot);
99 #if defined(CONFIG_XPA)
100 entrylo = pte_to_entrylo(pte.pte_high);
101 #elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
102 entrylo = pte.pte_high;
103 #else
104 entrylo = pte_to_entrylo(pte_val(pte));
105 #endif
106
107 local_irq_save(flags);
108 old_ctx = read_c0_entryhi();
109 write_c0_entryhi(vaddr & (PAGE_MASK << 1));
110 write_c0_entrylo0(entrylo);
111 write_c0_entrylo1(entrylo);
112 if (cpu_has_mmid) {
113 old_mmid = read_c0_memorymapid();
114 write_c0_memorymapid(MMID_KERNEL_WIRED);
115 }
116 #ifdef CONFIG_XPA
117 if (cpu_has_xpa) {
118 entrylo = (pte.pte_low & _PFNX_MASK);
119 writex_c0_entrylo0(entrylo);
120 writex_c0_entrylo1(entrylo);
121 }
122 #endif
123 tlbidx = num_wired_entries();
124 write_c0_wired(tlbidx + 1);
125 write_c0_index(tlbidx);
126 mtc0_tlbw_hazard();
127 tlb_write_indexed();
128 tlbw_use_hazard();
129 write_c0_entryhi(old_ctx);
130 if (cpu_has_mmid)
131 write_c0_memorymapid(old_mmid);
132 local_irq_restore(flags);
133
134 return (void*) vaddr;
135 }
136
kmap_coherent(struct page * page,unsigned long addr)137 void *kmap_coherent(struct page *page, unsigned long addr)
138 {
139 return __kmap_pgprot(page, addr, PAGE_KERNEL);
140 }
141
kmap_noncoherent(struct page * page,unsigned long addr)142 void *kmap_noncoherent(struct page *page, unsigned long addr)
143 {
144 return __kmap_pgprot(page, addr, PAGE_KERNEL_NC);
145 }
146
kunmap_coherent(void)147 void kunmap_coherent(void)
148 {
149 unsigned int wired;
150 unsigned long flags, old_ctx;
151
152 local_irq_save(flags);
153 old_ctx = read_c0_entryhi();
154 wired = num_wired_entries() - 1;
155 write_c0_wired(wired);
156 write_c0_index(wired);
157 write_c0_entryhi(UNIQUE_ENTRYHI(wired));
158 write_c0_entrylo0(0);
159 write_c0_entrylo1(0);
160 mtc0_tlbw_hazard();
161 tlb_write_indexed();
162 tlbw_use_hazard();
163 write_c0_entryhi(old_ctx);
164 local_irq_restore(flags);
165 pagefault_enable();
166 preempt_enable();
167 }
168
copy_user_highpage(struct page * to,struct page * from,unsigned long vaddr,struct vm_area_struct * vma)169 void copy_user_highpage(struct page *to, struct page *from,
170 unsigned long vaddr, struct vm_area_struct *vma)
171 {
172 void *vfrom, *vto;
173
174 vto = kmap_atomic(to);
175 if (cpu_has_dc_aliases &&
176 page_mapcount(from) && !Page_dcache_dirty(from)) {
177 vfrom = kmap_coherent(from, vaddr);
178 copy_page(vto, vfrom);
179 kunmap_coherent();
180 } else {
181 vfrom = kmap_atomic(from);
182 copy_page(vto, vfrom);
183 kunmap_atomic(vfrom);
184 }
185 if ((!cpu_has_ic_fills_f_dc) ||
186 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
187 flush_data_cache_page((unsigned long)vto);
188 kunmap_atomic(vto);
189 /* Make sure this page is cleared on other CPU's too before using it */
190 smp_wmb();
191 }
192
copy_to_user_page(struct vm_area_struct * vma,struct page * page,unsigned long vaddr,void * dst,const void * src,unsigned long len)193 void copy_to_user_page(struct vm_area_struct *vma,
194 struct page *page, unsigned long vaddr, void *dst, const void *src,
195 unsigned long len)
196 {
197 if (cpu_has_dc_aliases &&
198 page_mapcount(page) && !Page_dcache_dirty(page)) {
199 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
200 memcpy(vto, src, len);
201 kunmap_coherent();
202 } else {
203 memcpy(dst, src, len);
204 if (cpu_has_dc_aliases)
205 SetPageDcacheDirty(page);
206 }
207 if (vma->vm_flags & VM_EXEC)
208 flush_cache_page(vma, vaddr, page_to_pfn(page));
209 }
210
copy_from_user_page(struct vm_area_struct * vma,struct page * page,unsigned long vaddr,void * dst,const void * src,unsigned long len)211 void copy_from_user_page(struct vm_area_struct *vma,
212 struct page *page, unsigned long vaddr, void *dst, const void *src,
213 unsigned long len)
214 {
215 if (cpu_has_dc_aliases &&
216 page_mapcount(page) && !Page_dcache_dirty(page)) {
217 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
218 memcpy(dst, vfrom, len);
219 kunmap_coherent();
220 } else {
221 memcpy(dst, src, len);
222 if (cpu_has_dc_aliases)
223 SetPageDcacheDirty(page);
224 }
225 }
226 EXPORT_SYMBOL_GPL(copy_from_user_page);
227
fixrange_init(unsigned long start,unsigned long end,pgd_t * pgd_base)228 void __init fixrange_init(unsigned long start, unsigned long end,
229 pgd_t *pgd_base)
230 {
231 #ifdef CONFIG_HIGHMEM
232 pgd_t *pgd;
233 pud_t *pud;
234 pmd_t *pmd;
235 pte_t *pte;
236 int i, j, k;
237 unsigned long vaddr;
238
239 vaddr = start;
240 i = pgd_index(vaddr);
241 j = pud_index(vaddr);
242 k = pmd_index(vaddr);
243 pgd = pgd_base + i;
244
245 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
246 pud = (pud_t *)pgd;
247 for ( ; (j < PTRS_PER_PUD) && (vaddr < end); pud++, j++) {
248 pmd = (pmd_t *)pud;
249 for (; (k < PTRS_PER_PMD) && (vaddr < end); pmd++, k++) {
250 if (pmd_none(*pmd)) {
251 pte = (pte_t *) memblock_alloc_low(PAGE_SIZE,
252 PAGE_SIZE);
253 if (!pte)
254 panic("%s: Failed to allocate %lu bytes align=%lx\n",
255 __func__, PAGE_SIZE,
256 PAGE_SIZE);
257
258 set_pmd(pmd, __pmd((unsigned long)pte));
259 BUG_ON(pte != pte_offset_kernel(pmd, 0));
260 }
261 vaddr += PMD_SIZE;
262 }
263 k = 0;
264 }
265 j = 0;
266 }
267 #endif
268 }
269
270 struct maar_walk_info {
271 struct maar_config cfg[16];
272 unsigned int num_cfg;
273 };
274
maar_res_walk(unsigned long start_pfn,unsigned long nr_pages,void * data)275 static int maar_res_walk(unsigned long start_pfn, unsigned long nr_pages,
276 void *data)
277 {
278 struct maar_walk_info *wi = data;
279 struct maar_config *cfg = &wi->cfg[wi->num_cfg];
280 unsigned int maar_align;
281
282 /* MAAR registers hold physical addresses right shifted by 4 bits */
283 maar_align = BIT(MIPS_MAAR_ADDR_SHIFT + 4);
284
285 /* Fill in the MAAR config entry */
286 cfg->lower = ALIGN(PFN_PHYS(start_pfn), maar_align);
287 cfg->upper = ALIGN_DOWN(PFN_PHYS(start_pfn + nr_pages), maar_align) - 1;
288 cfg->attrs = MIPS_MAAR_S;
289
290 /* Ensure we don't overflow the cfg array */
291 if (!WARN_ON(wi->num_cfg >= ARRAY_SIZE(wi->cfg)))
292 wi->num_cfg++;
293
294 return 0;
295 }
296
297
platform_maar_init(unsigned num_pairs)298 unsigned __weak platform_maar_init(unsigned num_pairs)
299 {
300 unsigned int num_configured;
301 struct maar_walk_info wi;
302
303 wi.num_cfg = 0;
304 walk_system_ram_range(0, max_pfn, &wi, maar_res_walk);
305
306 num_configured = maar_config(wi.cfg, wi.num_cfg, num_pairs);
307 if (num_configured < wi.num_cfg)
308 pr_warn("Not enough MAAR pairs (%u) for all memory regions (%u)\n",
309 num_pairs, wi.num_cfg);
310
311 return num_configured;
312 }
313
maar_init(void)314 void maar_init(void)
315 {
316 unsigned num_maars, used, i;
317 phys_addr_t lower, upper, attr;
318 static struct {
319 struct maar_config cfgs[3];
320 unsigned used;
321 } recorded = { { { 0 } }, 0 };
322
323 if (!cpu_has_maar)
324 return;
325
326 /* Detect the number of MAARs */
327 write_c0_maari(~0);
328 back_to_back_c0_hazard();
329 num_maars = read_c0_maari() + 1;
330
331 /* MAARs should be in pairs */
332 WARN_ON(num_maars % 2);
333
334 /* Set MAARs using values we recorded already */
335 if (recorded.used) {
336 used = maar_config(recorded.cfgs, recorded.used, num_maars / 2);
337 BUG_ON(used != recorded.used);
338 } else {
339 /* Configure the required MAARs */
340 used = platform_maar_init(num_maars / 2);
341 }
342
343 /* Disable any further MAARs */
344 for (i = (used * 2); i < num_maars; i++) {
345 write_c0_maari(i);
346 back_to_back_c0_hazard();
347 write_c0_maar(0);
348 back_to_back_c0_hazard();
349 }
350
351 if (recorded.used)
352 return;
353
354 pr_info("MAAR configuration:\n");
355 for (i = 0; i < num_maars; i += 2) {
356 write_c0_maari(i);
357 back_to_back_c0_hazard();
358 upper = read_c0_maar();
359 #ifdef CONFIG_XPA
360 upper |= (phys_addr_t)readx_c0_maar() << MIPS_MAARX_ADDR_SHIFT;
361 #endif
362
363 write_c0_maari(i + 1);
364 back_to_back_c0_hazard();
365 lower = read_c0_maar();
366 #ifdef CONFIG_XPA
367 lower |= (phys_addr_t)readx_c0_maar() << MIPS_MAARX_ADDR_SHIFT;
368 #endif
369
370 attr = lower & upper;
371 lower = (lower & MIPS_MAAR_ADDR) << 4;
372 upper = ((upper & MIPS_MAAR_ADDR) << 4) | 0xffff;
373
374 pr_info(" [%d]: ", i / 2);
375 if ((attr & MIPS_MAAR_V) != MIPS_MAAR_V) {
376 pr_cont("disabled\n");
377 continue;
378 }
379
380 pr_cont("%pa-%pa", &lower, &upper);
381
382 if (attr & MIPS_MAAR_S)
383 pr_cont(" speculate");
384
385 pr_cont("\n");
386
387 /* Record the setup for use on secondary CPUs */
388 if (used <= ARRAY_SIZE(recorded.cfgs)) {
389 recorded.cfgs[recorded.used].lower = lower;
390 recorded.cfgs[recorded.used].upper = upper;
391 recorded.cfgs[recorded.used].attrs = attr;
392 recorded.used++;
393 }
394 }
395 }
396
397 #ifndef CONFIG_NUMA
paging_init(void)398 void __init paging_init(void)
399 {
400 unsigned long max_zone_pfns[MAX_NR_ZONES];
401
402 pagetable_init();
403
404 #ifdef CONFIG_ZONE_DMA
405 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
406 #endif
407 #ifdef CONFIG_ZONE_DMA32
408 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
409 #endif
410 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
411 #ifdef CONFIG_HIGHMEM
412 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
413
414 if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) {
415 printk(KERN_WARNING "This processor doesn't support highmem."
416 " %ldk highmem ignored\n",
417 (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10));
418 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn;
419 }
420 #endif
421
422 free_area_init(max_zone_pfns);
423 }
424
425 #ifdef CONFIG_64BIT
426 static struct kcore_list kcore_kseg0;
427 #endif
428
mem_init_free_highmem(void)429 static inline void __init mem_init_free_highmem(void)
430 {
431 #ifdef CONFIG_HIGHMEM
432 unsigned long tmp;
433
434 if (cpu_has_dc_aliases)
435 return;
436
437 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
438 struct page *page = pfn_to_page(tmp);
439
440 if (!memblock_is_memory(PFN_PHYS(tmp)))
441 SetPageReserved(page);
442 else
443 free_highmem_page(page);
444 }
445 #endif
446 }
447
mem_init(void)448 void __init mem_init(void)
449 {
450 /*
451 * When _PFN_SHIFT is greater than PAGE_SHIFT we won't have enough PTE
452 * bits to hold a full 32b physical address on MIPS32 systems.
453 */
454 BUILD_BUG_ON(IS_ENABLED(CONFIG_32BIT) && (_PFN_SHIFT > PAGE_SHIFT));
455
456 #ifdef CONFIG_HIGHMEM
457 max_mapnr = highend_pfn ? highend_pfn : max_low_pfn;
458 #else
459 max_mapnr = max_low_pfn;
460 #endif
461 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
462
463 maar_init();
464 memblock_free_all();
465 setup_zero_pages(); /* Setup zeroed pages. */
466 mem_init_free_highmem();
467
468 #ifdef CONFIG_64BIT
469 if ((unsigned long) &_text > (unsigned long) CKSEG0)
470 /* The -4 is a hack so that user tools don't have to handle
471 the overflow. */
472 kclist_add(&kcore_kseg0, (void *) CKSEG0,
473 0x80000000 - 4, KCORE_TEXT);
474 #endif
475 }
476 #endif /* !CONFIG_NUMA */
477
free_init_pages(const char * what,unsigned long begin,unsigned long end)478 void free_init_pages(const char *what, unsigned long begin, unsigned long end)
479 {
480 unsigned long pfn;
481
482 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
483 struct page *page = pfn_to_page(pfn);
484 void *addr = phys_to_virt(PFN_PHYS(pfn));
485
486 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
487 free_reserved_page(page);
488 }
489 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
490 }
491
492 void (*free_init_pages_eva)(void *begin, void *end) = NULL;
493
prom_free_prom_memory(void)494 void __weak __init prom_free_prom_memory(void)
495 {
496 /* nothing to do */
497 }
498
free_initmem(void)499 void __ref free_initmem(void)
500 {
501 prom_free_prom_memory();
502 /*
503 * Let the platform define a specific function to free the
504 * init section since EVA may have used any possible mapping
505 * between virtual and physical addresses.
506 */
507 if (free_init_pages_eva)
508 free_init_pages_eva((void *)&__init_begin, (void *)&__init_end);
509 else
510 free_initmem_default(POISON_FREE_INITMEM);
511 }
512
513 #ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
514 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
515 EXPORT_SYMBOL(__per_cpu_offset);
516
pcpu_cpu_distance(unsigned int from,unsigned int to)517 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
518 {
519 return node_distance(cpu_to_node(from), cpu_to_node(to));
520 }
521
pcpu_fc_alloc(unsigned int cpu,size_t size,size_t align)522 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size,
523 size_t align)
524 {
525 return memblock_alloc_try_nid(size, align, __pa(MAX_DMA_ADDRESS),
526 MEMBLOCK_ALLOC_ACCESSIBLE,
527 cpu_to_node(cpu));
528 }
529
pcpu_fc_free(void * ptr,size_t size)530 static void __init pcpu_fc_free(void *ptr, size_t size)
531 {
532 memblock_free_early(__pa(ptr), size);
533 }
534
setup_per_cpu_areas(void)535 void __init setup_per_cpu_areas(void)
536 {
537 unsigned long delta;
538 unsigned int cpu;
539 int rc;
540
541 /*
542 * Always reserve area for module percpu variables. That's
543 * what the legacy allocator did.
544 */
545 rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
546 PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
547 pcpu_cpu_distance,
548 pcpu_fc_alloc, pcpu_fc_free);
549 if (rc < 0)
550 panic("Failed to initialize percpu areas.");
551
552 delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
553 for_each_possible_cpu(cpu)
554 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
555 }
556 #endif
557
558 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
559 unsigned long pgd_current[NR_CPUS];
560 #endif
561
562 /*
563 * Align swapper_pg_dir in to 64K, allows its address to be loaded
564 * with a single LUI instruction in the TLB handlers. If we used
565 * __aligned(64K), its size would get rounded up to the alignment
566 * size, and waste space. So we place it in its own section and align
567 * it in the linker script.
568 */
569 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".bss..swapper_pg_dir");
570 #ifndef __PAGETABLE_PUD_FOLDED
571 pud_t invalid_pud_table[PTRS_PER_PUD] __page_aligned_bss;
572 #endif
573 #ifndef __PAGETABLE_PMD_FOLDED
574 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss;
575 EXPORT_SYMBOL_GPL(invalid_pmd_table);
576 #endif
577 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
578 EXPORT_SYMBOL(invalid_pte_table);
579
