Linux 5.7.6
[linux/fpc-iii.git] / arch / parisc / mm / init.c
blob01d7071b23f7ad3f70736dd0ae88fbca0fcaeed1
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/arch/parisc/mm/init.c
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)
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>
28 #include <asm/pgalloc.h>
29 #include <asm/pgtable.h>
30 #include <asm/tlb.h>
31 #include <asm/pdc_chassis.h>
32 #include <asm/mmzone.h>
33 #include <asm/sections.h>
34 #include <asm/msgbuf.h>
35 #include <asm/sparsemem.h>
37 extern int data_start;
38 extern void parisc_kernel_start(void); /* Kernel entry point in head.S */
40 #if CONFIG_PGTABLE_LEVELS == 3
41 /* NOTE: This layout exactly conforms to the hybrid L2/L3 page table layout
42 * with the first pmd adjacent to the pgd and below it. gcc doesn't actually
43 * guarantee that global objects will be laid out in memory in the same order
44 * as the order of declaration, so put these in different sections and use
45 * the linker script to order them. */
46 pmd_t pmd0[PTRS_PER_PMD] __attribute__ ((__section__ (".data..vm0.pmd"), aligned(PAGE_SIZE)));
47 #endif
49 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__ ((__section__ (".data..vm0.pgd"), aligned(PAGE_SIZE)));
50 pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __attribute__ ((__section__ (".data..vm0.pte"), aligned(PAGE_SIZE)));
52 static struct resource data_resource = {
53 .name = "Kernel data",
54 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
57 static struct resource code_resource = {
58 .name = "Kernel code",
59 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
62 static struct resource pdcdata_resource = {
63 .name = "PDC data (Page Zero)",
64 .start = 0,
65 .end = 0x9ff,
66 .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
69 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __ro_after_init;
71 /* The following array is initialized from the firmware specific
72 * information retrieved in kernel/inventory.c.
75 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __initdata;
76 int npmem_ranges __initdata;
78 #ifdef CONFIG_64BIT
79 #define MAX_MEM (1UL << MAX_PHYSMEM_BITS)
80 #else /* !CONFIG_64BIT */
81 #define MAX_MEM (3584U*1024U*1024U)
82 #endif /* !CONFIG_64BIT */
84 static unsigned long mem_limit __read_mostly = MAX_MEM;
86 static void __init mem_limit_func(void)
88 char *cp, *end;
89 unsigned long limit;
91 /* We need this before __setup() functions are called */
93 limit = MAX_MEM;
94 for (cp = boot_command_line; *cp; ) {
95 if (memcmp(cp, "mem=", 4) == 0) {
96 cp += 4;
97 limit = memparse(cp, &end);
98 if (end != cp)
99 break;
100 cp = end;
101 } else {
102 while (*cp != ' ' && *cp)
103 ++cp;
104 while (*cp == ' ')
105 ++cp;
109 if (limit < mem_limit)
110 mem_limit = limit;
113 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
115 static void __init setup_bootmem(void)
117 unsigned long mem_max;
118 #ifndef CONFIG_SPARSEMEM
119 physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
120 int npmem_holes;
121 #endif
122 int i, sysram_resource_count;
124 disable_sr_hashing(); /* Turn off space register hashing */
127 * Sort the ranges. Since the number of ranges is typically
128 * small, and performance is not an issue here, just do
129 * a simple insertion sort.
132 for (i = 1; i < npmem_ranges; i++) {
133 int j;
135 for (j = i; j > 0; j--) {
136 physmem_range_t tmp;
138 if (pmem_ranges[j-1].start_pfn <
139 pmem_ranges[j].start_pfn) {
141 break;
143 tmp = pmem_ranges[j-1];
144 pmem_ranges[j-1] = pmem_ranges[j];
145 pmem_ranges[j] = tmp;
149 #ifndef CONFIG_SPARSEMEM
151 * Throw out ranges that are too far apart (controlled by
152 * MAX_GAP).
155 for (i = 1; i < npmem_ranges; i++) {
156 if (pmem_ranges[i].start_pfn -
157 (pmem_ranges[i-1].start_pfn +
158 pmem_ranges[i-1].pages) > MAX_GAP) {
159 npmem_ranges = i;
160 printk("Large gap in memory detected (%ld pages). "
161 "Consider turning on CONFIG_SPARSEMEM\n",
162 pmem_ranges[i].start_pfn -
163 (pmem_ranges[i-1].start_pfn +
164 pmem_ranges[i-1].pages));
165 break;
168 #endif
170 /* Print the memory ranges */
171 pr_info("Memory Ranges:\n");
173 for (i = 0; i < npmem_ranges; i++) {
174 struct resource *res = &sysram_resources[i];
175 unsigned long start;
176 unsigned long size;
178 size = (pmem_ranges[i].pages << PAGE_SHIFT);
179 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
180 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
181 i, start, start + (size - 1), size >> 20);
183 /* request memory resource */
184 res->name = "System RAM";
185 res->start = start;
186 res->end = start + size - 1;
187 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
188 request_resource(&iomem_resource, res);
191 sysram_resource_count = npmem_ranges;
194 * For 32 bit kernels we limit the amount of memory we can
195 * support, in order to preserve enough kernel address space
196 * for other purposes. For 64 bit kernels we don't normally
197 * limit the memory, but this mechanism can be used to
198 * artificially limit the amount of memory (and it is written
199 * to work with multiple memory ranges).
202 mem_limit_func(); /* check for "mem=" argument */
204 mem_max = 0;
205 for (i = 0; i < npmem_ranges; i++) {
206 unsigned long rsize;
208 rsize = pmem_ranges[i].pages << PAGE_SHIFT;
209 if ((mem_max + rsize) > mem_limit) {
210 printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
211 if (mem_max == mem_limit)
212 npmem_ranges = i;
213 else {
214 pmem_ranges[i].pages = (mem_limit >> PAGE_SHIFT)
215 - (mem_max >> PAGE_SHIFT);
216 npmem_ranges = i + 1;
217 mem_max = mem_limit;
219 break;
221 mem_max += rsize;
224 printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
226 #ifndef CONFIG_SPARSEMEM
227 /* Merge the ranges, keeping track of the holes */
229 unsigned long end_pfn;
230 unsigned long hole_pages;
232 npmem_holes = 0;
233 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
234 for (i = 1; i < npmem_ranges; i++) {
236 hole_pages = pmem_ranges[i].start_pfn - end_pfn;
237 if (hole_pages) {
238 pmem_holes[npmem_holes].start_pfn = end_pfn;
239 pmem_holes[npmem_holes++].pages = hole_pages;
240 end_pfn += hole_pages;
242 end_pfn += pmem_ranges[i].pages;
245 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
246 npmem_ranges = 1;
248 #endif
251 * Initialize and free the full range of memory in each range.
254 max_pfn = 0;
255 for (i = 0; i < npmem_ranges; i++) {
256 unsigned long start_pfn;
257 unsigned long npages;
258 unsigned long start;
259 unsigned long size;
261 start_pfn = pmem_ranges[i].start_pfn;
262 npages = pmem_ranges[i].pages;
264 start = start_pfn << PAGE_SHIFT;
265 size = npages << PAGE_SHIFT;
267 /* add system RAM memblock */
268 memblock_add(start, size);
270 if ((start_pfn + npages) > max_pfn)
271 max_pfn = start_pfn + npages;
275 * We can't use memblock top-down allocations because we only
276 * created the initial mapping up to KERNEL_INITIAL_SIZE in
277 * the assembly bootup code.
279 memblock_set_bottom_up(true);
281 /* IOMMU is always used to access "high mem" on those boxes
282 * that can support enough mem that a PCI device couldn't
283 * directly DMA to any physical addresses.
284 * ISA DMA support will need to revisit this.
286 max_low_pfn = max_pfn;
288 /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
290 #define PDC_CONSOLE_IO_IODC_SIZE 32768
292 memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free +
293 PDC_CONSOLE_IO_IODC_SIZE));
294 memblock_reserve(__pa(KERNEL_BINARY_TEXT_START),
295 (unsigned long)(_end - KERNEL_BINARY_TEXT_START));
297 #ifndef CONFIG_SPARSEMEM
299 /* reserve the holes */
301 for (i = 0; i < npmem_holes; i++) {
302 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT),
303 (pmem_holes[i].pages << PAGE_SHIFT));
305 #endif
307 #ifdef CONFIG_BLK_DEV_INITRD
308 if (initrd_start) {
309 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
310 if (__pa(initrd_start) < mem_max) {
311 unsigned long initrd_reserve;
313 if (__pa(initrd_end) > mem_max) {
314 initrd_reserve = mem_max - __pa(initrd_start);
315 } else {
316 initrd_reserve = initrd_end - initrd_start;
318 initrd_below_start_ok = 1;
319 printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
321 memblock_reserve(__pa(initrd_start), initrd_reserve);
324 #endif
326 data_resource.start = virt_to_phys(&data_start);
327 data_resource.end = virt_to_phys(_end) - 1;
328 code_resource.start = virt_to_phys(_text);
329 code_resource.end = virt_to_phys(&data_start)-1;
331 /* We don't know which region the kernel will be in, so try
332 * all of them.
334 for (i = 0; i < sysram_resource_count; i++) {
335 struct resource *res = &sysram_resources[i];
336 request_resource(res, &code_resource);
337 request_resource(res, &data_resource);
339 request_resource(&sysram_resources[0], &pdcdata_resource);
341 /* Initialize Page Deallocation Table (PDT) and check for bad memory. */
342 pdc_pdt_init();
344 memblock_allow_resize();
345 memblock_dump_all();
348 static bool kernel_set_to_readonly;
350 static void __init map_pages(unsigned long start_vaddr,
351 unsigned long start_paddr, unsigned long size,
352 pgprot_t pgprot, int force)
354 pmd_t *pmd;
355 pte_t *pg_table;
356 unsigned long end_paddr;
357 unsigned long start_pmd;
358 unsigned long start_pte;
359 unsigned long tmp1;
360 unsigned long tmp2;
361 unsigned long address;
362 unsigned long vaddr;
363 unsigned long ro_start;
364 unsigned long ro_end;
365 unsigned long kernel_start, kernel_end;
367 ro_start = __pa((unsigned long)_text);
368 ro_end = __pa((unsigned long)&data_start);
369 kernel_start = __pa((unsigned long)&__init_begin);
370 kernel_end = __pa((unsigned long)&_end);
372 end_paddr = start_paddr + size;
374 /* for 2-level configuration PTRS_PER_PMD is 0 so start_pmd will be 0 */
375 start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
376 start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
378 address = start_paddr;
379 vaddr = start_vaddr;
380 while (address < end_paddr) {
381 pgd_t *pgd = pgd_offset_k(vaddr);
382 p4d_t *p4d = p4d_offset(pgd, vaddr);
383 pud_t *pud = pud_offset(p4d, vaddr);
385 #if CONFIG_PGTABLE_LEVELS == 3
386 if (pud_none(*pud)) {
387 pmd = memblock_alloc(PAGE_SIZE << PMD_ORDER,
388 PAGE_SIZE << PMD_ORDER);
389 if (!pmd)
390 panic("pmd allocation failed.\n");
391 pud_populate(NULL, pud, pmd);
393 #endif
395 pmd = pmd_offset(pud, vaddr);
396 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) {
397 if (pmd_none(*pmd)) {
398 pg_table = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
399 if (!pg_table)
400 panic("page table allocation failed\n");
401 pmd_populate_kernel(NULL, pmd, pg_table);
404 pg_table = pte_offset_kernel(pmd, vaddr);
405 for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
406 pte_t pte;
407 pgprot_t prot;
408 bool huge = false;
410 if (force) {
411 prot = pgprot;
412 } else if (address < kernel_start || address >= kernel_end) {
413 /* outside kernel memory */
414 prot = PAGE_KERNEL;
415 } else if (!kernel_set_to_readonly) {
416 /* still initializing, allow writing to RO memory */
417 prot = PAGE_KERNEL_RWX;
418 huge = true;
419 } else if (address >= ro_start) {
420 /* Code (ro) and Data areas */
421 prot = (address < ro_end) ?
422 PAGE_KERNEL_EXEC : PAGE_KERNEL;
423 huge = true;
424 } else {
425 prot = PAGE_KERNEL;
428 pte = __mk_pte(address, prot);
429 if (huge)
430 pte = pte_mkhuge(pte);
432 if (address >= end_paddr)
433 break;
435 set_pte(pg_table, pte);
437 address += PAGE_SIZE;
438 vaddr += PAGE_SIZE;
440 start_pte = 0;
442 if (address >= end_paddr)
443 break;
445 start_pmd = 0;
449 void __init set_kernel_text_rw(int enable_read_write)
451 unsigned long start = (unsigned long) __init_begin;
452 unsigned long end = (unsigned long) &data_start;
454 map_pages(start, __pa(start), end-start,
455 PAGE_KERNEL_RWX, enable_read_write ? 1:0);
457 /* force the kernel to see the new page table entries */
458 flush_cache_all();
459 flush_tlb_all();
462 void __ref free_initmem(void)
464 unsigned long init_begin = (unsigned long)__init_begin;
465 unsigned long init_end = (unsigned long)__init_end;
466 unsigned long kernel_end = (unsigned long)&_end;
468 /* Remap kernel text and data, but do not touch init section yet. */
469 kernel_set_to_readonly = true;
470 map_pages(init_end, __pa(init_end), kernel_end - init_end,
471 PAGE_KERNEL, 0);
473 /* The init text pages are marked R-X. We have to
474 * flush the icache and mark them RW-
476 * This is tricky, because map_pages is in the init section.
477 * Do a dummy remap of the data section first (the data
478 * section is already PAGE_KERNEL) to pull in the TLB entries
479 * for map_kernel */
480 map_pages(init_begin, __pa(init_begin), init_end - init_begin,
481 PAGE_KERNEL_RWX, 1);
482 /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute
483 * map_pages */
484 map_pages(init_begin, __pa(init_begin), init_end - init_begin,
485 PAGE_KERNEL, 1);
487 /* force the kernel to see the new TLB entries */
488 __flush_tlb_range(0, init_begin, kernel_end);
490 /* finally dump all the instructions which were cached, since the
491 * pages are no-longer executable */
492 flush_icache_range(init_begin, init_end);
494 free_initmem_default(POISON_FREE_INITMEM);
496 /* set up a new led state on systems shipped LED State panel */
497 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
501 #ifdef CONFIG_STRICT_KERNEL_RWX
502 void mark_rodata_ro(void)
504 /* rodata memory was already mapped with KERNEL_RO access rights by
505 pagetable_init() and map_pages(). No need to do additional stuff here */
506 unsigned long roai_size = __end_ro_after_init - __start_ro_after_init;
508 pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10);
510 #endif
514 * Just an arbitrary offset to serve as a "hole" between mapping areas
515 * (between top of physical memory and a potential pcxl dma mapping
516 * area, and below the vmalloc mapping area).
518 * The current 32K value just means that there will be a 32K "hole"
519 * between mapping areas. That means that any out-of-bounds memory
520 * accesses will hopefully be caught. The vmalloc() routines leaves
521 * a hole of 4kB between each vmalloced area for the same reason.
524 /* Leave room for gateway page expansion */
525 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
526 #error KERNEL_MAP_START is in gateway reserved region
527 #endif
528 #define MAP_START (KERNEL_MAP_START)
530 #define VM_MAP_OFFSET (32*1024)
531 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
532 & ~(VM_MAP_OFFSET-1)))
534 void *parisc_vmalloc_start __ro_after_init;
535 EXPORT_SYMBOL(parisc_vmalloc_start);
537 #ifdef CONFIG_PA11
538 unsigned long pcxl_dma_start __ro_after_init;
539 #endif
541 void __init mem_init(void)
543 /* Do sanity checks on IPC (compat) structures */
544 BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48);
545 #ifndef CONFIG_64BIT
546 BUILD_BUG_ON(sizeof(struct semid64_ds) != 80);
547 BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104);
548 BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104);
549 #endif
550 #ifdef CONFIG_COMPAT
551 BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm));
552 BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80);
553 BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104);
554 BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104);
555 #endif
557 /* Do sanity checks on page table constants */
558 BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t));
559 BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t));
560 BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t));
561 BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD
562 > BITS_PER_LONG);
564 high_memory = __va((max_pfn << PAGE_SHIFT));
565 set_max_mapnr(max_low_pfn);
566 memblock_free_all();
568 #ifdef CONFIG_PA11
569 if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
570 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
571 parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start
572 + PCXL_DMA_MAP_SIZE);
573 } else
574 #endif
575 parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
577 mem_init_print_info(NULL);
579 #if 0
581 * Do not expose the virtual kernel memory layout to userspace.
582 * But keep code for debugging purposes.
584 printk("virtual kernel memory layout:\n"
585 " vmalloc : 0x%px - 0x%px (%4ld MB)\n"
586 " fixmap : 0x%px - 0x%px (%4ld kB)\n"
587 " memory : 0x%px - 0x%px (%4ld MB)\n"
588 " .init : 0x%px - 0x%px (%4ld kB)\n"
589 " .data : 0x%px - 0x%px (%4ld kB)\n"
590 " .text : 0x%px - 0x%px (%4ld kB)\n",
592 (void*)VMALLOC_START, (void*)VMALLOC_END,
593 (VMALLOC_END - VMALLOC_START) >> 20,
595 (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE),
596 (unsigned long)(FIXMAP_SIZE / 1024),
598 __va(0), high_memory,
599 ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
601 __init_begin, __init_end,
602 ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
604 _etext, _edata,
605 ((unsigned long)_edata - (unsigned long)_etext) >> 10,
607 _text, _etext,
608 ((unsigned long)_etext - (unsigned long)_text) >> 10);
609 #endif
612 unsigned long *empty_zero_page __ro_after_init;
613 EXPORT_SYMBOL(empty_zero_page);
616 * pagetable_init() sets up the page tables
618 * Note that gateway_init() places the Linux gateway page at page 0.
619 * Since gateway pages cannot be dereferenced this has the desirable
620 * side effect of trapping those pesky NULL-reference errors in the
621 * kernel.
623 static void __init pagetable_init(void)
625 int range;
627 /* Map each physical memory range to its kernel vaddr */
629 for (range = 0; range < npmem_ranges; range++) {
630 unsigned long start_paddr;
631 unsigned long end_paddr;
632 unsigned long size;
634 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
635 size = pmem_ranges[range].pages << PAGE_SHIFT;
636 end_paddr = start_paddr + size;
638 map_pages((unsigned long)__va(start_paddr), start_paddr,
639 size, PAGE_KERNEL, 0);
642 #ifdef CONFIG_BLK_DEV_INITRD
643 if (initrd_end && initrd_end > mem_limit) {
644 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
645 map_pages(initrd_start, __pa(initrd_start),
646 initrd_end - initrd_start, PAGE_KERNEL, 0);
648 #endif
650 empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
651 if (!empty_zero_page)
652 panic("zero page allocation failed.\n");
656 static void __init gateway_init(void)
658 unsigned long linux_gateway_page_addr;
659 /* FIXME: This is 'const' in order to trick the compiler
660 into not treating it as DP-relative data. */
661 extern void * const linux_gateway_page;
663 linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
666 * Setup Linux Gateway page.
668 * The Linux gateway page will reside in kernel space (on virtual
669 * page 0), so it doesn't need to be aliased into user space.
672 map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
673 PAGE_SIZE, PAGE_GATEWAY, 1);
676 static void __init parisc_bootmem_free(void)
678 unsigned long zones_size[MAX_NR_ZONES] = { 0, };
679 unsigned long holes_size[MAX_NR_ZONES] = { 0, };
680 unsigned long mem_start_pfn = ~0UL, mem_end_pfn = 0, mem_size_pfn = 0;
681 int i;
683 for (i = 0; i < npmem_ranges; i++) {
684 unsigned long start = pmem_ranges[i].start_pfn;
685 unsigned long size = pmem_ranges[i].pages;
686 unsigned long end = start + size;
688 if (mem_start_pfn > start)
689 mem_start_pfn = start;
690 if (mem_end_pfn < end)
691 mem_end_pfn = end;
692 mem_size_pfn += size;
695 zones_size[0] = mem_end_pfn - mem_start_pfn;
696 holes_size[0] = zones_size[0] - mem_size_pfn;
698 free_area_init_node(0, zones_size, mem_start_pfn, holes_size);
701 void __init paging_init(void)
703 setup_bootmem();
704 pagetable_init();
705 gateway_init();
706 flush_cache_all_local(); /* start with known state */
707 flush_tlb_all_local(NULL);
710 * Mark all memblocks as present for sparsemem using
711 * memory_present() and then initialize sparsemem.
713 memblocks_present();
714 sparse_init();
715 parisc_bootmem_free();
718 #ifdef CONFIG_PA20
721 * Currently, all PA20 chips have 18 bit protection IDs, which is the
722 * limiting factor (space ids are 32 bits).
725 #define NR_SPACE_IDS 262144
727 #else
730 * Currently we have a one-to-one relationship between space IDs and
731 * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
732 * support 15 bit protection IDs, so that is the limiting factor.
733 * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
734 * probably not worth the effort for a special case here.
737 #define NR_SPACE_IDS 32768
739 #endif /* !CONFIG_PA20 */
741 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
742 #define SID_ARRAY_SIZE (NR_SPACE_IDS / (8 * sizeof(long)))
744 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
745 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
746 static unsigned long space_id_index;
747 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
748 static unsigned long dirty_space_ids = 0;
750 static DEFINE_SPINLOCK(sid_lock);
752 unsigned long alloc_sid(void)
754 unsigned long index;
756 spin_lock(&sid_lock);
758 if (free_space_ids == 0) {
759 if (dirty_space_ids != 0) {
760 spin_unlock(&sid_lock);
761 flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
762 spin_lock(&sid_lock);
764 BUG_ON(free_space_ids == 0);
767 free_space_ids--;
769 index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
770 space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
771 space_id_index = index;
773 spin_unlock(&sid_lock);
775 return index << SPACEID_SHIFT;
778 void free_sid(unsigned long spaceid)
780 unsigned long index = spaceid >> SPACEID_SHIFT;
781 unsigned long *dirty_space_offset;
783 dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
784 index &= (BITS_PER_LONG - 1);
786 spin_lock(&sid_lock);
788 BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */
790 *dirty_space_offset |= (1L << index);
791 dirty_space_ids++;
793 spin_unlock(&sid_lock);
797 #ifdef CONFIG_SMP
798 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
800 int i;
802 /* NOTE: sid_lock must be held upon entry */
804 *ndirtyptr = dirty_space_ids;
805 if (dirty_space_ids != 0) {
806 for (i = 0; i < SID_ARRAY_SIZE; i++) {
807 dirty_array[i] = dirty_space_id[i];
808 dirty_space_id[i] = 0;
810 dirty_space_ids = 0;
813 return;
816 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
818 int i;
820 /* NOTE: sid_lock must be held upon entry */
822 if (ndirty != 0) {
823 for (i = 0; i < SID_ARRAY_SIZE; i++) {
824 space_id[i] ^= dirty_array[i];
827 free_space_ids += ndirty;
828 space_id_index = 0;
832 #else /* CONFIG_SMP */
834 static void recycle_sids(void)
836 int i;
838 /* NOTE: sid_lock must be held upon entry */
840 if (dirty_space_ids != 0) {
841 for (i = 0; i < SID_ARRAY_SIZE; i++) {
842 space_id[i] ^= dirty_space_id[i];
843 dirty_space_id[i] = 0;
846 free_space_ids += dirty_space_ids;
847 dirty_space_ids = 0;
848 space_id_index = 0;
851 #endif
854 * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
855 * purged, we can safely reuse the space ids that were released but
856 * not flushed from the tlb.
859 #ifdef CONFIG_SMP
861 static unsigned long recycle_ndirty;
862 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
863 static unsigned int recycle_inuse;
865 void flush_tlb_all(void)
867 int do_recycle;
869 __inc_irq_stat(irq_tlb_count);
870 do_recycle = 0;
871 spin_lock(&sid_lock);
872 if (dirty_space_ids > RECYCLE_THRESHOLD) {
873 BUG_ON(recycle_inuse); /* FIXME: Use a semaphore/wait queue here */
874 get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
875 recycle_inuse++;
876 do_recycle++;
878 spin_unlock(&sid_lock);
879 on_each_cpu(flush_tlb_all_local, NULL, 1);
880 if (do_recycle) {
881 spin_lock(&sid_lock);
882 recycle_sids(recycle_ndirty,recycle_dirty_array);
883 recycle_inuse = 0;
884 spin_unlock(&sid_lock);
887 #else
888 void flush_tlb_all(void)
890 __inc_irq_stat(irq_tlb_count);
891 spin_lock(&sid_lock);
892 flush_tlb_all_local(NULL);
893 recycle_sids();
894 spin_unlock(&sid_lock);
896 #endif