1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/arch/parisc/mm/init.c
4 *
5 * Copyright (C) 1995 Linus Torvalds
6 * Copyright 1999 SuSE GmbH
7 * changed by Philipp Rumpf
8 * Copyright 1999 Philipp Rumpf (prumpf@tux.org)
9 * Copyright 2004 Randolph Chung (tausq@debian.org)
10 * Copyright 2006-2007 Helge Deller (deller@gmx.de)
11 *
12 */
13
14
15 #include <linux/module.h>
16 #include <linux/mm.h>
17 #include <linux/memblock.h>
18 #include <linux/gfp.h>
19 #include <linux/delay.h>
20 #include <linux/init.h>
21 #include <linux/initrd.h>
22 #include <linux/swap.h>
23 #include <linux/unistd.h>
24 #include <linux/nodemask.h> /* for node_online_map */
25 #include <linux/pagemap.h> /* for release_pages */
26 #include <linux/compat.h>
27
28 #include <asm/pgalloc.h>
29 #include <asm/tlb.h>
30 #include <asm/pdc_chassis.h>
31 #include <asm/mmzone.h>
32 #include <asm/sections.h>
33 #include <asm/msgbuf.h>
34 #include <asm/sparsemem.h>
35
36 extern int data_start;
37 extern void parisc_kernel_start(void); /* Kernel entry point in head.S */
38
39 #if CONFIG_PGTABLE_LEVELS == 3
40 pmd_t pmd0[PTRS_PER_PMD] __section(".data..vm0.pmd") __attribute__ ((aligned(PAGE_SIZE)));
41 #endif
42
43 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".data..vm0.pgd") __attribute__ ((aligned(PAGE_SIZE)));
44 pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __section(".data..vm0.pte") __attribute__ ((aligned(PAGE_SIZE)));
45
46 static struct resource data_resource = {
47 .name = "Kernel data",
48 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
49 };
50
51 static struct resource code_resource = {
52 .name = "Kernel code",
53 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
54 };
55
56 static struct resource pdcdata_resource = {
57 .name = "PDC data (Page Zero)",
58 .start = 0,
59 .end = 0x9ff,
60 .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
61 };
62
63 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __ro_after_init;
64
65 /* The following array is initialized from the firmware specific
66 * information retrieved in kernel/inventory.c.
67 */
68
69 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __initdata;
70 int npmem_ranges __initdata;
71
72 #ifdef CONFIG_64BIT
73 #define MAX_MEM (1UL << MAX_PHYSMEM_BITS)
74 #else /* !CONFIG_64BIT */
75 #define MAX_MEM (3584U*1024U*1024U)
76 #endif /* !CONFIG_64BIT */
77
78 static unsigned long mem_limit __read_mostly = MAX_MEM;
79
mem_limit_func(void)80 static void __init mem_limit_func(void)
81 {
82 char *cp, *end;
83 unsigned long limit;
84
85 /* We need this before __setup() functions are called */
86
87 limit = MAX_MEM;
88 for (cp = boot_command_line; *cp; ) {
89 if (memcmp(cp, "mem=", 4) == 0) {
90 cp += 4;
91 limit = memparse(cp, &end);
92 if (end != cp)
93 break;
94 cp = end;
95 } else {
96 while (*cp != ' ' && *cp)
97 ++cp;
98 while (*cp == ' ')
99 ++cp;
100 }
101 }
102
103 if (limit < mem_limit)
104 mem_limit = limit;
105 }
106
107 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
108
setup_bootmem(void)109 static void __init setup_bootmem(void)
110 {
111 unsigned long mem_max;
112 #ifndef CONFIG_SPARSEMEM
113 physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
114 int npmem_holes;
115 #endif
116 int i, sysram_resource_count;
117
118 disable_sr_hashing(); /* Turn off space register hashing */
119
120 /*
121 * Sort the ranges. Since the number of ranges is typically
122 * small, and performance is not an issue here, just do
123 * a simple insertion sort.
124 */
125
126 for (i = 1; i < npmem_ranges; i++) {
127 int j;
128
129 for (j = i; j > 0; j--) {
130 physmem_range_t tmp;
131
132 if (pmem_ranges[j-1].start_pfn <
133 pmem_ranges[j].start_pfn) {
134
135 break;
136 }
137 tmp = pmem_ranges[j-1];
138 pmem_ranges[j-1] = pmem_ranges[j];
139 pmem_ranges[j] = tmp;
140 }
141 }
142
143 #ifndef CONFIG_SPARSEMEM
144 /*
145 * Throw out ranges that are too far apart (controlled by
146 * MAX_GAP).
147 */
148
149 for (i = 1; i < npmem_ranges; i++) {
150 if (pmem_ranges[i].start_pfn -
151 (pmem_ranges[i-1].start_pfn +
152 pmem_ranges[i-1].pages) > MAX_GAP) {
153 npmem_ranges = i;
154 printk("Large gap in memory detected (%ld pages). "
155 "Consider turning on CONFIG_SPARSEMEM\n",
156 pmem_ranges[i].start_pfn -
157 (pmem_ranges[i-1].start_pfn +
158 pmem_ranges[i-1].pages));
159 break;
160 }
161 }
162 #endif
163
164 /* Print the memory ranges */
165 pr_info("Memory Ranges:\n");
166
167 for (i = 0; i < npmem_ranges; i++) {
168 struct resource *res = &sysram_resources[i];
169 unsigned long start;
170 unsigned long size;
171
172 size = (pmem_ranges[i].pages << PAGE_SHIFT);
173 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
174 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
175 i, start, start + (size - 1), size >> 20);
176
177 /* request memory resource */
178 res->name = "System RAM";
179 res->start = start;
180 res->end = start + size - 1;
181 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
182 request_resource(&iomem_resource, res);
183 }
184
185 sysram_resource_count = npmem_ranges;
186
187 /*
188 * For 32 bit kernels we limit the amount of memory we can
189 * support, in order to preserve enough kernel address space
190 * for other purposes. For 64 bit kernels we don't normally
191 * limit the memory, but this mechanism can be used to
192 * artificially limit the amount of memory (and it is written
193 * to work with multiple memory ranges).
194 */
195
196 mem_limit_func(); /* check for "mem=" argument */
197
198 mem_max = 0;
199 for (i = 0; i < npmem_ranges; i++) {
200 unsigned long rsize;
201
202 rsize = pmem_ranges[i].pages << PAGE_SHIFT;
203 if ((mem_max + rsize) > mem_limit) {
204 printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
205 if (mem_max == mem_limit)
206 npmem_ranges = i;
207 else {
208 pmem_ranges[i].pages = (mem_limit >> PAGE_SHIFT)
209 - (mem_max >> PAGE_SHIFT);
210 npmem_ranges = i + 1;
211 mem_max = mem_limit;
212 }
213 break;
214 }
215 mem_max += rsize;
216 }
217
218 printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
219
220 #ifndef CONFIG_SPARSEMEM
221 /* Merge the ranges, keeping track of the holes */
222 {
223 unsigned long end_pfn;
224 unsigned long hole_pages;
225
226 npmem_holes = 0;
227 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
228 for (i = 1; i < npmem_ranges; i++) {
229
230 hole_pages = pmem_ranges[i].start_pfn - end_pfn;
231 if (hole_pages) {
232 pmem_holes[npmem_holes].start_pfn = end_pfn;
233 pmem_holes[npmem_holes++].pages = hole_pages;
234 end_pfn += hole_pages;
235 }
236 end_pfn += pmem_ranges[i].pages;
237 }
238
239 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
240 npmem_ranges = 1;
241 }
242 #endif
243
244 /*
245 * Initialize and free the full range of memory in each range.
246 */
247
248 max_pfn = 0;
249 for (i = 0; i < npmem_ranges; i++) {
250 unsigned long start_pfn;
251 unsigned long npages;
252 unsigned long start;
253 unsigned long size;
254
255 start_pfn = pmem_ranges[i].start_pfn;
256 npages = pmem_ranges[i].pages;
257
258 start = start_pfn << PAGE_SHIFT;
259 size = npages << PAGE_SHIFT;
260
261 /* add system RAM memblock */
262 memblock_add(start, size);
263
264 if ((start_pfn + npages) > max_pfn)
265 max_pfn = start_pfn + npages;
266 }
267
268 /*
269 * We can't use memblock top-down allocations because we only
270 * created the initial mapping up to KERNEL_INITIAL_SIZE in
271 * the assembly bootup code.
272 */
273 memblock_set_bottom_up(true);
274
275 /* IOMMU is always used to access "high mem" on those boxes
276 * that can support enough mem that a PCI device couldn't
277 * directly DMA to any physical addresses.
278 * ISA DMA support will need to revisit this.
279 */
280 max_low_pfn = max_pfn;
281
282 /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
283
284 #define PDC_CONSOLE_IO_IODC_SIZE 32768
285
286 memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free +
287 PDC_CONSOLE_IO_IODC_SIZE));
288 memblock_reserve(__pa(KERNEL_BINARY_TEXT_START),
289 (unsigned long)(_end - KERNEL_BINARY_TEXT_START));
290
291 #ifndef CONFIG_SPARSEMEM
292
293 /* reserve the holes */
294
295 for (i = 0; i < npmem_holes; i++) {
296 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT),
297 (pmem_holes[i].pages << PAGE_SHIFT));
298 }
299 #endif
300
301 #ifdef CONFIG_BLK_DEV_INITRD
302 if (initrd_start) {
303 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
304 if (__pa(initrd_start) < mem_max) {
305 unsigned long initrd_reserve;
306
307 if (__pa(initrd_end) > mem_max) {
308 initrd_reserve = mem_max - __pa(initrd_start);
309 } else {
310 initrd_reserve = initrd_end - initrd_start;
311 }
312 initrd_below_start_ok = 1;
313 printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
314
315 memblock_reserve(__pa(initrd_start), initrd_reserve);
316 }
317 }
318 #endif
319
320 data_resource.start = virt_to_phys(&data_start);
321 data_resource.end = virt_to_phys(_end) - 1;
322 code_resource.start = virt_to_phys(_text);
323 code_resource.end = virt_to_phys(&data_start)-1;
324
325 /* We don't know which region the kernel will be in, so try
326 * all of them.
327 */
328 for (i = 0; i < sysram_resource_count; i++) {
329 struct resource *res = &sysram_resources[i];
330 request_resource(res, &code_resource);
331 request_resource(res, &data_resource);
332 }
333 request_resource(&sysram_resources[0], &pdcdata_resource);
334
335 /* Initialize Page Deallocation Table (PDT) and check for bad memory. */
336 pdc_pdt_init();
337
338 memblock_allow_resize();
339 memblock_dump_all();
340 }
341
342 static bool kernel_set_to_readonly;
343
map_pages(unsigned long start_vaddr,unsigned long start_paddr,unsigned long size,pgprot_t pgprot,int force)344 static void __ref map_pages(unsigned long start_vaddr,
345 unsigned long start_paddr, unsigned long size,
346 pgprot_t pgprot, int force)
347 {
348 pmd_t *pmd;
349 pte_t *pg_table;
350 unsigned long end_paddr;
351 unsigned long start_pmd;
352 unsigned long start_pte;
353 unsigned long tmp1;
354 unsigned long tmp2;
355 unsigned long address;
356 unsigned long vaddr;
357 unsigned long ro_start;
358 unsigned long ro_end;
359 unsigned long kernel_start, kernel_end;
360
361 ro_start = __pa((unsigned long)_text);
362 ro_end = __pa((unsigned long)&data_start);
363 kernel_start = __pa((unsigned long)&__init_begin);
364 kernel_end = __pa((unsigned long)&_end);
365
366 end_paddr = start_paddr + size;
367
368 /* for 2-level configuration PTRS_PER_PMD is 0 so start_pmd will be 0 */
369 start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
370 start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
371
372 address = start_paddr;
373 vaddr = start_vaddr;
374 while (address < end_paddr) {
375 pgd_t *pgd = pgd_offset_k(vaddr);
376 p4d_t *p4d = p4d_offset(pgd, vaddr);
377 pud_t *pud = pud_offset(p4d, vaddr);
378
379 #if CONFIG_PGTABLE_LEVELS == 3
380 if (pud_none(*pud)) {
381 pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER,
382 PAGE_SIZE << PMD_TABLE_ORDER);
383 if (!pmd)
384 panic("pmd allocation failed.\n");
385 pud_populate(NULL, pud, pmd);
386 }
387 #endif
388
389 pmd = pmd_offset(pud, vaddr);
390 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) {
391 if (pmd_none(*pmd)) {
392 pg_table = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
393 if (!pg_table)
394 panic("page table allocation failed\n");
395 pmd_populate_kernel(NULL, pmd, pg_table);
396 }
397
398 pg_table = pte_offset_kernel(pmd, vaddr);
399 for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
400 pte_t pte;
401 pgprot_t prot;
402 bool huge = false;
403
404 if (force) {
405 prot = pgprot;
406 } else if (address < kernel_start || address >= kernel_end) {
407 /* outside kernel memory */
408 prot = PAGE_KERNEL;
409 } else if (!kernel_set_to_readonly) {
410 /* still initializing, allow writing to RO memory */
411 prot = PAGE_KERNEL_RWX;
412 huge = true;
413 } else if (address >= ro_start) {
414 /* Code (ro) and Data areas */
415 prot = (address < ro_end) ?
416 PAGE_KERNEL_EXEC : PAGE_KERNEL;
417 huge = true;
418 } else {
419 prot = PAGE_KERNEL;
420 }
421
422 pte = __mk_pte(address, prot);
423 if (huge)
424 pte = pte_mkhuge(pte);
425
426 if (address >= end_paddr)
427 break;
428
429 set_pte(pg_table, pte);
430
431 address += PAGE_SIZE;
432 vaddr += PAGE_SIZE;
433 }
434 start_pte = 0;
435
436 if (address >= end_paddr)
437 break;
438 }
439 start_pmd = 0;
440 }
441 }
442
set_kernel_text_rw(int enable_read_write)443 void __init set_kernel_text_rw(int enable_read_write)
444 {
445 unsigned long start = (unsigned long) __init_begin;
446 unsigned long end = (unsigned long) &data_start;
447
448 map_pages(start, __pa(start), end-start,
449 PAGE_KERNEL_RWX, enable_read_write ? 1:0);
450
451 /* force the kernel to see the new page table entries */
452 flush_cache_all();
453 flush_tlb_all();
454 }
455
free_initmem(void)456 void free_initmem(void)
457 {
458 unsigned long init_begin = (unsigned long)__init_begin;
459 unsigned long init_end = (unsigned long)__init_end;
460 unsigned long kernel_end = (unsigned long)&_end;
461
462 /* Remap kernel text and data, but do not touch init section yet. */
463 kernel_set_to_readonly = true;
464 map_pages(init_end, __pa(init_end), kernel_end - init_end,
465 PAGE_KERNEL, 0);
466
467 /* The init text pages are marked R-X. We have to
468 * flush the icache and mark them RW-
469 *
470 * Do a dummy remap of the data section first (the data
471 * section is already PAGE_KERNEL) to pull in the TLB entries
472 * for map_kernel */
473 map_pages(init_begin, __pa(init_begin), init_end - init_begin,
474 PAGE_KERNEL_RWX, 1);
475 /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute
476 * map_pages */
477 map_pages(init_begin, __pa(init_begin), init_end - init_begin,
478 PAGE_KERNEL, 1);
479
480 /* force the kernel to see the new TLB entries */
481 __flush_tlb_range(0, init_begin, kernel_end);
482
483 /* finally dump all the instructions which were cached, since the
484 * pages are no-longer executable */
485 flush_icache_range(init_begin, init_end);
486
487 free_initmem_default(POISON_FREE_INITMEM);
488
489 /* set up a new led state on systems shipped LED State panel */
490 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
491 }
492
493
494 #ifdef CONFIG_STRICT_KERNEL_RWX
mark_rodata_ro(void)495 void mark_rodata_ro(void)
496 {
497 /* rodata memory was already mapped with KERNEL_RO access rights by
498 pagetable_init() and map_pages(). No need to do additional stuff here */
499 unsigned long roai_size = __end_ro_after_init - __start_ro_after_init;
500
501 pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10);
502 }
503 #endif
504
505
506 /*
507 * Just an arbitrary offset to serve as a "hole" between mapping areas
508 * (between top of physical memory and a potential pcxl dma mapping
509 * area, and below the vmalloc mapping area).
510 *
511 * The current 32K value just means that there will be a 32K "hole"
512 * between mapping areas. That means that any out-of-bounds memory
513 * accesses will hopefully be caught. The vmalloc() routines leaves
514 * a hole of 4kB between each vmalloced area for the same reason.
515 */
516
517 /* Leave room for gateway page expansion */
518 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
519 #error KERNEL_MAP_START is in gateway reserved region
520 #endif
521 #define MAP_START (KERNEL_MAP_START)
522
523 #define VM_MAP_OFFSET (32*1024)
524 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
525 & ~(VM_MAP_OFFSET-1)))
526
527 void *parisc_vmalloc_start __ro_after_init;
528 EXPORT_SYMBOL(parisc_vmalloc_start);
529
530 #ifdef CONFIG_PA11
531 unsigned long pcxl_dma_start __ro_after_init;
532 #endif
533
mem_init(void)534 void __init mem_init(void)
535 {
536 /* Do sanity checks on IPC (compat) structures */
537 BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48);
538 #ifndef CONFIG_64BIT
539 BUILD_BUG_ON(sizeof(struct semid64_ds) != 80);
540 BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104);
541 BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104);
542 #endif
543 #ifdef CONFIG_COMPAT
544 BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm));
545 BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80);
546 BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104);
547 BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104);
548 #endif
549
550 /* Do sanity checks on page table constants */
551 BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t));
552 BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t));
553 BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t));
554 BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD
555 > BITS_PER_LONG);
556 #if CONFIG_PGTABLE_LEVELS == 3
557 BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PMD);
558 #else
559 BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PGD);
560 #endif
561
562 high_memory = __va((max_pfn << PAGE_SHIFT));
563 set_max_mapnr(max_low_pfn);
564 memblock_free_all();
565
566 #ifdef CONFIG_PA11
567 if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
568 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
569 parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start
570 + PCXL_DMA_MAP_SIZE);
571 } else
572 #endif
573 parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
574
575 #if 0
576 /*
577 * Do not expose the virtual kernel memory layout to userspace.
578 * But keep code for debugging purposes.
579 */
580 printk("virtual kernel memory layout:\n"
581 " vmalloc : 0x%px - 0x%px (%4ld MB)\n"
582 " fixmap : 0x%px - 0x%px (%4ld kB)\n"
583 " memory : 0x%px - 0x%px (%4ld MB)\n"
584 " .init : 0x%px - 0x%px (%4ld kB)\n"
585 " .data : 0x%px - 0x%px (%4ld kB)\n"
586 " .text : 0x%px - 0x%px (%4ld kB)\n",
587
588 (void*)VMALLOC_START, (void*)VMALLOC_END,
589 (VMALLOC_END - VMALLOC_START) >> 20,
590
591 (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE),
592 (unsigned long)(FIXMAP_SIZE / 1024),
593
594 __va(0), high_memory,
595 ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
596
597 __init_begin, __init_end,
598 ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
599
600 _etext, _edata,
601 ((unsigned long)_edata - (unsigned long)_etext) >> 10,
602
603 _text, _etext,
604 ((unsigned long)_etext - (unsigned long)_text) >> 10);
605 #endif
606 }
607
608 unsigned long *empty_zero_page __ro_after_init;
609 EXPORT_SYMBOL(empty_zero_page);
610
611 /*
612 * pagetable_init() sets up the page tables
613 *
614 * Note that gateway_init() places the Linux gateway page at page 0.
615 * Since gateway pages cannot be dereferenced this has the desirable
616 * side effect of trapping those pesky NULL-reference errors in the
617 * kernel.
618 */
pagetable_init(void)619 static void __init pagetable_init(void)
620 {
621 int range;
622
623 /* Map each physical memory range to its kernel vaddr */
624
625 for (range = 0; range < npmem_ranges; range++) {
626 unsigned long start_paddr;
627 unsigned long end_paddr;
628 unsigned long size;
629
630 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
631 size = pmem_ranges[range].pages << PAGE_SHIFT;
632 end_paddr = start_paddr + size;
633
634 map_pages((unsigned long)__va(start_paddr), start_paddr,
635 size, PAGE_KERNEL, 0);
636 }
637
638 #ifdef CONFIG_BLK_DEV_INITRD
639 if (initrd_end && initrd_end > mem_limit) {
640 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
641 map_pages(initrd_start, __pa(initrd_start),
642 initrd_end - initrd_start, PAGE_KERNEL, 0);
643 }
644 #endif
645
646 empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
647 if (!empty_zero_page)
648 panic("zero page allocation failed.\n");
649
650 }
651
gateway_init(void)652 static void __init gateway_init(void)
653 {
654 unsigned long linux_gateway_page_addr;
655 /* FIXME: This is 'const' in order to trick the compiler
656 into not treating it as DP-relative data. */
657 extern void * const linux_gateway_page;
658
659 linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
660
661 /*
662 * Setup Linux Gateway page.
663 *
664 * The Linux gateway page will reside in kernel space (on virtual
665 * page 0), so it doesn't need to be aliased into user space.
666 */
667
668 map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
669 PAGE_SIZE, PAGE_GATEWAY, 1);
670 }
671
parisc_bootmem_free(void)672 static void __init parisc_bootmem_free(void)
673 {
674 unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
675
676 max_zone_pfn[0] = memblock_end_of_DRAM();
677
678 free_area_init(max_zone_pfn);
679 }
680
paging_init(void)681 void __init paging_init(void)
682 {
683 setup_bootmem();
684 pagetable_init();
685 gateway_init();
686 flush_cache_all_local(); /* start with known state */
687 flush_tlb_all_local(NULL);
688
689 sparse_init();
690 parisc_bootmem_free();
691 }
692
693 #ifdef CONFIG_PA20
694
695 /*
696 * Currently, all PA20 chips have 18 bit protection IDs, which is the
697 * limiting factor (space ids are 32 bits).
698 */
699
700 #define NR_SPACE_IDS 262144
701
702 #else
703
704 /*
705 * Currently we have a one-to-one relationship between space IDs and
706 * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
707 * support 15 bit protection IDs, so that is the limiting factor.
708 * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
709 * probably not worth the effort for a special case here.
710 */
711
712 #define NR_SPACE_IDS 32768
713
714 #endif /* !CONFIG_PA20 */
715
716 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
717 #define SID_ARRAY_SIZE (NR_SPACE_IDS / (8 * sizeof(long)))
718
719 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
720 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
721 static unsigned long space_id_index;
722 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
723 static unsigned long dirty_space_ids = 0;
724
725 static DEFINE_SPINLOCK(sid_lock);
726
alloc_sid(void)727 unsigned long alloc_sid(void)
728 {
729 unsigned long index;
730
731 spin_lock(&sid_lock);
732
733 if (free_space_ids == 0) {
734 if (dirty_space_ids != 0) {
735 spin_unlock(&sid_lock);
736 flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
737 spin_lock(&sid_lock);
738 }
739 BUG_ON(free_space_ids == 0);
740 }
741
742 free_space_ids--;
743
744 index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
745 space_id[BIT_WORD(index)] |= BIT_MASK(index);
746 space_id_index = index;
747
748 spin_unlock(&sid_lock);
749
750 return index << SPACEID_SHIFT;
751 }
752
free_sid(unsigned long spaceid)753 void free_sid(unsigned long spaceid)
754 {
755 unsigned long index = spaceid >> SPACEID_SHIFT;
756 unsigned long *dirty_space_offset, mask;
757
758 dirty_space_offset = &dirty_space_id[BIT_WORD(index)];
759 mask = BIT_MASK(index);
760
761 spin_lock(&sid_lock);
762
763 BUG_ON(*dirty_space_offset & mask); /* attempt to free space id twice */
764
765 *dirty_space_offset |= mask;
766 dirty_space_ids++;
767
768 spin_unlock(&sid_lock);
769 }
770
771
772 #ifdef CONFIG_SMP
get_dirty_sids(unsigned long * ndirtyptr,unsigned long * dirty_array)773 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
774 {
775 int i;
776
777 /* NOTE: sid_lock must be held upon entry */
778
779 *ndirtyptr = dirty_space_ids;
780 if (dirty_space_ids != 0) {
781 for (i = 0; i < SID_ARRAY_SIZE; i++) {
782 dirty_array[i] = dirty_space_id[i];
783 dirty_space_id[i] = 0;
784 }
785 dirty_space_ids = 0;
786 }
787
788 return;
789 }
790
recycle_sids(unsigned long ndirty,unsigned long * dirty_array)791 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
792 {
793 int i;
794
795 /* NOTE: sid_lock must be held upon entry */
796
797 if (ndirty != 0) {
798 for (i = 0; i < SID_ARRAY_SIZE; i++) {
799 space_id[i] ^= dirty_array[i];
800 }
801
802 free_space_ids += ndirty;
803 space_id_index = 0;
804 }
805 }
806
807 #else /* CONFIG_SMP */
808
recycle_sids(void)809 static void recycle_sids(void)
810 {
811 int i;
812
813 /* NOTE: sid_lock must be held upon entry */
814
815 if (dirty_space_ids != 0) {
816 for (i = 0; i < SID_ARRAY_SIZE; i++) {
817 space_id[i] ^= dirty_space_id[i];
818 dirty_space_id[i] = 0;
819 }
820
821 free_space_ids += dirty_space_ids;
822 dirty_space_ids = 0;
823 space_id_index = 0;
824 }
825 }
826 #endif
827
828 /*
829 * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
830 * purged, we can safely reuse the space ids that were released but
831 * not flushed from the tlb.
832 */
833
834 #ifdef CONFIG_SMP
835
836 static unsigned long recycle_ndirty;
837 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
838 static unsigned int recycle_inuse;
839
flush_tlb_all(void)840 void flush_tlb_all(void)
841 {
842 int do_recycle;
843
844 do_recycle = 0;
845 spin_lock(&sid_lock);
846 __inc_irq_stat(irq_tlb_count);
847 if (dirty_space_ids > RECYCLE_THRESHOLD) {
848 BUG_ON(recycle_inuse); /* FIXME: Use a semaphore/wait queue here */
849 get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
850 recycle_inuse++;
851 do_recycle++;
852 }
853 spin_unlock(&sid_lock);
854 on_each_cpu(flush_tlb_all_local, NULL, 1);
855 if (do_recycle) {
856 spin_lock(&sid_lock);
857 recycle_sids(recycle_ndirty,recycle_dirty_array);
858 recycle_inuse = 0;
859 spin_unlock(&sid_lock);
860 }
861 }
862 #else
flush_tlb_all(void)863 void flush_tlb_all(void)
864 {
865 spin_lock(&sid_lock);
866 __inc_irq_stat(irq_tlb_count);
867 flush_tlb_all_local(NULL);
868 recycle_sids();
869 spin_unlock(&sid_lock);
870 }
871 #endif
872