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/kmap_types.h>
40 #include <asm/maar.h>
41 #include <asm/mmu_context.h>
42 #include <asm/sections.h>
43 #include <asm/pgalloc.h>
44 #include <asm/tlb.h>
45 #include <asm/fixmap.h>
46
47 /*
48 * We have up to 8 empty zeroed pages so we can map one of the right colour
49 * when needed. This is necessary only on R4000 / R4400 SC and MC versions
50 * where we have to avoid VCED / VECI exceptions for good performance at
51 * any price. Since page is never written to after the initialization we
52 * don't have to care about aliases on other CPUs.
53 */
54 unsigned long empty_zero_page, zero_page_mask;
55 EXPORT_SYMBOL_GPL(empty_zero_page);
56 EXPORT_SYMBOL(zero_page_mask);
57
58 /*
59 * Not static inline because used by IP27 special magic initialization code
60 */
setup_zero_pages(void)61 void setup_zero_pages(void)
62 {
63 unsigned int order, i;
64 struct page *page;
65
66 if (cpu_has_vce)
67 order = 3;
68 else
69 order = 0;
70
71 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
72 if (!empty_zero_page)
73 panic("Oh boy, that early out of memory?");
74
75 page = virt_to_page((void *)empty_zero_page);
76 split_page(page, order);
77 for (i = 0; i < (1 << order); i++, page++)
78 mark_page_reserved(page);
79
80 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK;
81 }
82
__kmap_pgprot(struct page * page,unsigned long addr,pgprot_t prot)83 static void *__kmap_pgprot(struct page *page, unsigned long addr, pgprot_t prot)
84 {
85 enum fixed_addresses idx;
86 unsigned int old_mmid;
87 unsigned long vaddr, flags, entrylo;
88 unsigned long old_ctx;
89 pte_t pte;
90 int tlbidx;
91
92 BUG_ON(Page_dcache_dirty(page));
93
94 preempt_disable();
95 pagefault_disable();
96 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
97 idx += in_interrupt() ? FIX_N_COLOURS : 0;
98 vaddr = __fix_to_virt(FIX_CMAP_END - idx);
99 pte = mk_pte(page, prot);
100 #if defined(CONFIG_XPA)
101 entrylo = pte_to_entrylo(pte.pte_high);
102 #elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
103 entrylo = pte.pte_high;
104 #else
105 entrylo = pte_to_entrylo(pte_val(pte));
106 #endif
107
108 local_irq_save(flags);
109 old_ctx = read_c0_entryhi();
110 write_c0_entryhi(vaddr & (PAGE_MASK << 1));
111 write_c0_entrylo0(entrylo);
112 write_c0_entrylo1(entrylo);
113 if (cpu_has_mmid) {
114 old_mmid = read_c0_memorymapid();
115 write_c0_memorymapid(MMID_KERNEL_WIRED);
116 }
117 #ifdef CONFIG_XPA
118 if (cpu_has_xpa) {
119 entrylo = (pte.pte_low & _PFNX_MASK);
120 writex_c0_entrylo0(entrylo);
121 writex_c0_entrylo1(entrylo);
122 }
123 #endif
124 tlbidx = num_wired_entries();
125 write_c0_wired(tlbidx + 1);
126 write_c0_index(tlbidx);
127 mtc0_tlbw_hazard();
128 tlb_write_indexed();
129 tlbw_use_hazard();
130 write_c0_entryhi(old_ctx);
131 if (cpu_has_mmid)
132 write_c0_memorymapid(old_mmid);
133 local_irq_restore(flags);
134
135 return (void*) vaddr;
136 }
137
kmap_coherent(struct page * page,unsigned long addr)138 void *kmap_coherent(struct page *page, unsigned long addr)
139 {
140 return __kmap_pgprot(page, addr, PAGE_KERNEL);
141 }
142
kmap_noncoherent(struct page * page,unsigned long addr)143 void *kmap_noncoherent(struct page *page, unsigned long addr)
144 {
145 return __kmap_pgprot(page, addr, PAGE_KERNEL_NC);
146 }
147
kunmap_coherent(void)148 void kunmap_coherent(void)
149 {
150 unsigned int wired;
151 unsigned long flags, old_ctx;
152
153 local_irq_save(flags);
154 old_ctx = read_c0_entryhi();
155 wired = num_wired_entries() - 1;
156 write_c0_wired(wired);
157 write_c0_index(wired);
158 write_c0_entryhi(UNIQUE_ENTRYHI(wired));
159 write_c0_entrylo0(0);
160 write_c0_entrylo1(0);
161 mtc0_tlbw_hazard();
162 tlb_write_indexed();
163 tlbw_use_hazard();
164 write_c0_entryhi(old_ctx);
165 local_irq_restore(flags);
166 pagefault_enable();
167 preempt_enable();
168 }
169
copy_user_highpage(struct page * to,struct page * from,unsigned long vaddr,struct vm_area_struct * vma)170 void copy_user_highpage(struct page *to, struct page *from,
171 unsigned long vaddr, struct vm_area_struct *vma)
172 {
173 void *vfrom, *vto;
174
175 vto = kmap_atomic(to);
176 if (cpu_has_dc_aliases &&
177 page_mapcount(from) && !Page_dcache_dirty(from)) {
178 vfrom = kmap_coherent(from, vaddr);
179 copy_page(vto, vfrom);
180 kunmap_coherent();
181 } else {
182 vfrom = kmap_atomic(from);
183 copy_page(vto, vfrom);
184 kunmap_atomic(vfrom);
185 }
186 if ((!cpu_has_ic_fills_f_dc) ||
187 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
188 flush_data_cache_page((unsigned long)vto);
189 kunmap_atomic(vto);
190 /* Make sure this page is cleared on other CPU's too before using it */
191 smp_wmb();
192 }
193
copy_to_user_page(struct vm_area_struct * vma,struct page * page,unsigned long vaddr,void * dst,const void * src,unsigned long len)194 void copy_to_user_page(struct vm_area_struct *vma,
195 struct page *page, unsigned long vaddr, void *dst, const void *src,
196 unsigned long len)
197 {
198 if (cpu_has_dc_aliases &&
199 page_mapcount(page) && !Page_dcache_dirty(page)) {
200 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
201 memcpy(vto, src, len);
202 kunmap_coherent();
203 } else {
204 memcpy(dst, src, len);
205 if (cpu_has_dc_aliases)
206 SetPageDcacheDirty(page);
207 }
208 if (vma->vm_flags & VM_EXEC)
209 flush_cache_page(vma, vaddr, page_to_pfn(page));
210 }
211
copy_from_user_page(struct vm_area_struct * vma,struct page * page,unsigned long vaddr,void * dst,const void * src,unsigned long len)212 void copy_from_user_page(struct vm_area_struct *vma,
213 struct page *page, unsigned long vaddr, void *dst, const void *src,
214 unsigned long len)
215 {
216 if (cpu_has_dc_aliases &&
217 page_mapcount(page) && !Page_dcache_dirty(page)) {
218 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
219 memcpy(dst, vfrom, len);
220 kunmap_coherent();
221 } else {
222 memcpy(dst, src, len);
223 if (cpu_has_dc_aliases)
224 SetPageDcacheDirty(page);
225 }
226 }
227 EXPORT_SYMBOL_GPL(copy_from_user_page);
228
fixrange_init(unsigned long start,unsigned long end,pgd_t * pgd_base)229 void __init fixrange_init(unsigned long start, unsigned long end,
230 pgd_t *pgd_base)
231 {
232 #ifdef CONFIG_HIGHMEM
233 pgd_t *pgd;
234 pud_t *pud;
235 pmd_t *pmd;
236 pte_t *pte;
237 int i, j, k;
238 unsigned long vaddr;
239
240 vaddr = start;
241 i = pgd_index(vaddr);
242 j = pud_index(vaddr);
243 k = pmd_index(vaddr);
244 pgd = pgd_base + i;
245
246 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
247 pud = (pud_t *)pgd;
248 for ( ; (j < PTRS_PER_PUD) && (vaddr < end); pud++, j++) {
249 pmd = (pmd_t *)pud;
250 for (; (k < PTRS_PER_PMD) && (vaddr < end); pmd++, k++) {
251 if (pmd_none(*pmd)) {
252 pte = (pte_t *) memblock_alloc_low(PAGE_SIZE,
253 PAGE_SIZE);
254 if (!pte)
255 panic("%s: Failed to allocate %lu bytes align=%lx\n",
256 __func__, PAGE_SIZE,
257 PAGE_SIZE);
258
259 set_pmd(pmd, __pmd((unsigned long)pte));
260 BUG_ON(pte != pte_offset_kernel(pmd, 0));
261 }
262 vaddr += PMD_SIZE;
263 }
264 k = 0;
265 }
266 j = 0;
267 }
268 #endif
269 }
270
271 struct maar_walk_info {
272 struct maar_config cfg[16];
273 unsigned int num_cfg;
274 };
275
maar_res_walk(unsigned long start_pfn,unsigned long nr_pages,void * data)276 static int maar_res_walk(unsigned long start_pfn, unsigned long nr_pages,
277 void *data)
278 {
279 struct maar_walk_info *wi = data;
280 struct maar_config *cfg = &wi->cfg[wi->num_cfg];
281 unsigned int maar_align;
282
283 /* MAAR registers hold physical addresses right shifted by 4 bits */
284 maar_align = BIT(MIPS_MAAR_ADDR_SHIFT + 4);
285
286 /* Fill in the MAAR config entry */
287 cfg->lower = ALIGN(PFN_PHYS(start_pfn), maar_align);
288 cfg->upper = ALIGN_DOWN(PFN_PHYS(start_pfn + nr_pages), maar_align) - 1;
289 cfg->attrs = MIPS_MAAR_S;
290
291 /* Ensure we don't overflow the cfg array */
292 if (!WARN_ON(wi->num_cfg >= ARRAY_SIZE(wi->cfg)))
293 wi->num_cfg++;
294
295 return 0;
296 }
297
298
platform_maar_init(unsigned num_pairs)299 unsigned __weak platform_maar_init(unsigned num_pairs)
300 {
301 unsigned int num_configured;
302 struct maar_walk_info wi;
303
304 wi.num_cfg = 0;
305 walk_system_ram_range(0, max_pfn, &wi, maar_res_walk);
306
307 num_configured = maar_config(wi.cfg, wi.num_cfg, num_pairs);
308 if (num_configured < wi.num_cfg)
309 pr_warn("Not enough MAAR pairs (%u) for all memory regions (%u)\n",
310 num_pairs, wi.num_cfg);
311
312 return num_configured;
313 }
314
maar_init(void)315 void maar_init(void)
316 {
317 unsigned num_maars, used, i;
318 phys_addr_t lower, upper, attr;
319 static struct {
320 struct maar_config cfgs[3];
321 unsigned used;
322 } recorded = { { { 0 } }, 0 };
323
324 if (!cpu_has_maar)
325 return;
326
327 /* Detect the number of MAARs */
328 write_c0_maari(~0);
329 back_to_back_c0_hazard();
330 num_maars = read_c0_maari() + 1;
331
332 /* MAARs should be in pairs */
333 WARN_ON(num_maars % 2);
334
335 /* Set MAARs using values we recorded already */
336 if (recorded.used) {
337 used = maar_config(recorded.cfgs, recorded.used, num_maars / 2);
338 BUG_ON(used != recorded.used);
339 } else {
340 /* Configure the required MAARs */
341 used = platform_maar_init(num_maars / 2);
342 }
343
344 /* Disable any further MAARs */
345 for (i = (used * 2); i < num_maars; i++) {
346 write_c0_maari(i);
347 back_to_back_c0_hazard();
348 write_c0_maar(0);
349 back_to_back_c0_hazard();
350 }
351
352 if (recorded.used)
353 return;
354
355 pr_info("MAAR configuration:\n");
356 for (i = 0; i < num_maars; i += 2) {
357 write_c0_maari(i);
358 back_to_back_c0_hazard();
359 upper = read_c0_maar();
360 #ifdef CONFIG_XPA
361 upper |= (phys_addr_t)readx_c0_maar() << MIPS_MAARX_ADDR_SHIFT;
362 #endif
363
364 write_c0_maari(i + 1);
365 back_to_back_c0_hazard();
366 lower = read_c0_maar();
367 #ifdef CONFIG_XPA
368 lower |= (phys_addr_t)readx_c0_maar() << MIPS_MAARX_ADDR_SHIFT;
369 #endif
370
371 attr = lower & upper;
372 lower = (lower & MIPS_MAAR_ADDR) << 4;
373 upper = ((upper & MIPS_MAAR_ADDR) << 4) | 0xffff;
374
375 pr_info(" [%d]: ", i / 2);
376 if ((attr & MIPS_MAAR_V) != MIPS_MAAR_V) {
377 pr_cont("disabled\n");
378 continue;
379 }
380
381 pr_cont("%pa-%pa", &lower, &upper);
382
383 if (attr & MIPS_MAAR_S)
384 pr_cont(" speculate");
385
386 pr_cont("\n");
387
388 /* Record the setup for use on secondary CPUs */
389 if (used <= ARRAY_SIZE(recorded.cfgs)) {
390 recorded.cfgs[recorded.used].lower = lower;
391 recorded.cfgs[recorded.used].upper = upper;
392 recorded.cfgs[recorded.used].attrs = attr;
393 recorded.used++;
394 }
395 }
396 }
397
398 #ifndef CONFIG_NEED_MULTIPLE_NODES
paging_init(void)399 void __init paging_init(void)
400 {
401 unsigned long max_zone_pfns[MAX_NR_ZONES];
402
403 pagetable_init();
404
405 #ifdef CONFIG_HIGHMEM
406 kmap_init();
407 #endif
408 #ifdef CONFIG_ZONE_DMA
409 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
410 #endif
411 #ifdef CONFIG_ZONE_DMA32
412 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
413 #endif
414 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
415 #ifdef CONFIG_HIGHMEM
416 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
417
418 if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) {
419 printk(KERN_WARNING "This processor doesn't support highmem."
420 " %ldk highmem ignored\n",
421 (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10));
422 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn;
423 }
424 #endif
425
426 free_area_init(max_zone_pfns);
427 }
428
429 #ifdef CONFIG_64BIT
430 static struct kcore_list kcore_kseg0;
431 #endif
432
mem_init_free_highmem(void)433 static inline void __init mem_init_free_highmem(void)
434 {
435 #ifdef CONFIG_HIGHMEM
436 unsigned long tmp;
437
438 if (cpu_has_dc_aliases)
439 return;
440
441 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
442 struct page *page = pfn_to_page(tmp);
443
444 if (!memblock_is_memory(PFN_PHYS(tmp)))
445 SetPageReserved(page);
446 else
447 free_highmem_page(page);
448 }
449 #endif
450 }
451
mem_init(void)452 void __init mem_init(void)
453 {
454 /*
455 * When _PFN_SHIFT is greater than PAGE_SHIFT we won't have enough PTE
456 * bits to hold a full 32b physical address on MIPS32 systems.
457 */
458 BUILD_BUG_ON(IS_ENABLED(CONFIG_32BIT) && (_PFN_SHIFT > PAGE_SHIFT));
459
460 #ifdef CONFIG_HIGHMEM
461 #ifdef CONFIG_DISCONTIGMEM
462 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
463 #endif
464 max_mapnr = highend_pfn ? highend_pfn : max_low_pfn;
465 #else
466 max_mapnr = max_low_pfn;
467 #endif
468 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
469
470 maar_init();
471 memblock_free_all();
472 setup_zero_pages(); /* Setup zeroed pages. */
473 mem_init_free_highmem();
474 mem_init_print_info(NULL);
475
476 #ifdef CONFIG_64BIT
477 if ((unsigned long) &_text > (unsigned long) CKSEG0)
478 /* The -4 is a hack so that user tools don't have to handle
479 the overflow. */
480 kclist_add(&kcore_kseg0, (void *) CKSEG0,
481 0x80000000 - 4, KCORE_TEXT);
482 #endif
483 }
484 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
485
free_init_pages(const char * what,unsigned long begin,unsigned long end)486 void free_init_pages(const char *what, unsigned long begin, unsigned long end)
487 {
488 unsigned long pfn;
489
490 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
491 struct page *page = pfn_to_page(pfn);
492 void *addr = phys_to_virt(PFN_PHYS(pfn));
493
494 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
495 free_reserved_page(page);
496 }
497 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
498 }
499
500 void (*free_init_pages_eva)(void *begin, void *end) = NULL;
501
free_initmem(void)502 void __ref free_initmem(void)
503 {
504 prom_free_prom_memory();
505 /*
506 * Let the platform define a specific function to free the
507 * init section since EVA may have used any possible mapping
508 * between virtual and physical addresses.
509 */
510 if (free_init_pages_eva)
511 free_init_pages_eva((void *)&__init_begin, (void *)&__init_end);
512 else
513 free_initmem_default(POISON_FREE_INITMEM);
514 }
515
516 #ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
517 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
518 EXPORT_SYMBOL(__per_cpu_offset);
519
pcpu_cpu_distance(unsigned int from,unsigned int to)520 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
521 {
522 return node_distance(cpu_to_node(from), cpu_to_node(to));
523 }
524
pcpu_fc_alloc(unsigned int cpu,size_t size,size_t align)525 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size,
526 size_t align)
527 {
528 return memblock_alloc_try_nid(size, align, __pa(MAX_DMA_ADDRESS),
529 MEMBLOCK_ALLOC_ACCESSIBLE,
530 cpu_to_node(cpu));
531 }
532
pcpu_fc_free(void * ptr,size_t size)533 static void __init pcpu_fc_free(void *ptr, size_t size)
534 {
535 memblock_free_early(__pa(ptr), size);
536 }
537
setup_per_cpu_areas(void)538 void __init setup_per_cpu_areas(void)
539 {
540 unsigned long delta;
541 unsigned int cpu;
542 int rc;
543
544 /*
545 * Always reserve area for module percpu variables. That's
546 * what the legacy allocator did.
547 */
548 rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
549 PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
550 pcpu_cpu_distance,
551 pcpu_fc_alloc, pcpu_fc_free);
552 if (rc < 0)
553 panic("Failed to initialize percpu areas.");
554
555 delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
556 for_each_possible_cpu(cpu)
557 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
558 }
559 #endif
560
561 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
562 unsigned long pgd_current[NR_CPUS];
563 #endif
564
565 /*
566 * Align swapper_pg_dir in to 64K, allows its address to be loaded
567 * with a single LUI instruction in the TLB handlers. If we used
568 * __aligned(64K), its size would get rounded up to the alignment
569 * size, and waste space. So we place it in its own section and align
570 * it in the linker script.
571 */
572 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".bss..swapper_pg_dir");
573 #ifndef __PAGETABLE_PUD_FOLDED
574 pud_t invalid_pud_table[PTRS_PER_PUD] __page_aligned_bss;
575 #endif
576 #ifndef __PAGETABLE_PMD_FOLDED
577 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss;
578 EXPORT_SYMBOL_GPL(invalid_pmd_table);
579 #endif
580 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
581 EXPORT_SYMBOL(invalid_pte_table);
582
