xref: /openbmc/linux/arch/parisc/mm/init.c (revision 5a170e9e)
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/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 
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 /* NOTE: This layout exactly conforms to the hybrid L2/L3 page table layout
41  * with the first pmd adjacent to the pgd and below it. gcc doesn't actually
42  * guarantee that global objects will be laid out in memory in the same order
43  * as the order of declaration, so put these in different sections and use
44  * the linker script to order them. */
45 pmd_t pmd0[PTRS_PER_PMD] __attribute__ ((__section__ (".data..vm0.pmd"), aligned(PAGE_SIZE)));
46 #endif
47 
48 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__ ((__section__ (".data..vm0.pgd"), aligned(PAGE_SIZE)));
49 pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __attribute__ ((__section__ (".data..vm0.pte"), aligned(PAGE_SIZE)));
50 
51 #ifdef CONFIG_DISCONTIGMEM
52 struct node_map_data node_data[MAX_NUMNODES] __read_mostly;
53 signed char pfnnid_map[PFNNID_MAP_MAX] __read_mostly;
54 #endif
55 
56 static struct resource data_resource = {
57 	.name	= "Kernel data",
58 	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
59 };
60 
61 static struct resource code_resource = {
62 	.name	= "Kernel code",
63 	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
64 };
65 
66 static struct resource pdcdata_resource = {
67 	.name	= "PDC data (Page Zero)",
68 	.start	= 0,
69 	.end	= 0x9ff,
70 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM,
71 };
72 
73 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __read_mostly;
74 
75 /* The following array is initialized from the firmware specific
76  * information retrieved in kernel/inventory.c.
77  */
78 
79 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __read_mostly;
80 int npmem_ranges __read_mostly;
81 
82 /*
83  * get_memblock() allocates pages via memblock.
84  * We can't use memblock_find_in_range(0, KERNEL_INITIAL_SIZE) here since it
85  * doesn't allocate from bottom to top which is needed because we only created
86  * the initial mapping up to KERNEL_INITIAL_SIZE in the assembly bootup code.
87  */
88 static void * __init get_memblock(unsigned long size)
89 {
90 	static phys_addr_t search_addr __initdata;
91 	phys_addr_t phys;
92 
93 	if (!search_addr)
94 		search_addr = PAGE_ALIGN(__pa((unsigned long) &_end));
95 	search_addr = ALIGN(search_addr, size);
96 	while (!memblock_is_region_memory(search_addr, size) ||
97 		memblock_is_region_reserved(search_addr, size)) {
98 		search_addr += size;
99 	}
100 	phys = search_addr;
101 
102 	if (phys)
103 		memblock_reserve(phys, size);
104 	else
105 		panic("get_memblock() failed.\n");
106 
107 	memset(__va(phys), 0, size);
108 
109 	return __va(phys);
110 }
111 
112 #ifdef CONFIG_64BIT
113 #define MAX_MEM         (~0UL)
114 #else /* !CONFIG_64BIT */
115 #define MAX_MEM         (3584U*1024U*1024U)
116 #endif /* !CONFIG_64BIT */
117 
118 static unsigned long mem_limit __read_mostly = MAX_MEM;
119 
120 static void __init mem_limit_func(void)
121 {
122 	char *cp, *end;
123 	unsigned long limit;
124 
125 	/* We need this before __setup() functions are called */
126 
127 	limit = MAX_MEM;
128 	for (cp = boot_command_line; *cp; ) {
129 		if (memcmp(cp, "mem=", 4) == 0) {
130 			cp += 4;
131 			limit = memparse(cp, &end);
132 			if (end != cp)
133 				break;
134 			cp = end;
135 		} else {
136 			while (*cp != ' ' && *cp)
137 				++cp;
138 			while (*cp == ' ')
139 				++cp;
140 		}
141 	}
142 
143 	if (limit < mem_limit)
144 		mem_limit = limit;
145 }
146 
147 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
148 
149 static void __init setup_bootmem(void)
150 {
151 	unsigned long mem_max;
152 #ifndef CONFIG_DISCONTIGMEM
153 	physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
154 	int npmem_holes;
155 #endif
156 	int i, sysram_resource_count;
157 
158 	disable_sr_hashing(); /* Turn off space register hashing */
159 
160 	/*
161 	 * Sort the ranges. Since the number of ranges is typically
162 	 * small, and performance is not an issue here, just do
163 	 * a simple insertion sort.
164 	 */
165 
166 	for (i = 1; i < npmem_ranges; i++) {
167 		int j;
168 
169 		for (j = i; j > 0; j--) {
170 			unsigned long tmp;
171 
172 			if (pmem_ranges[j-1].start_pfn <
173 			    pmem_ranges[j].start_pfn) {
174 
175 				break;
176 			}
177 			tmp = pmem_ranges[j-1].start_pfn;
178 			pmem_ranges[j-1].start_pfn = pmem_ranges[j].start_pfn;
179 			pmem_ranges[j].start_pfn = tmp;
180 			tmp = pmem_ranges[j-1].pages;
181 			pmem_ranges[j-1].pages = pmem_ranges[j].pages;
182 			pmem_ranges[j].pages = tmp;
183 		}
184 	}
185 
186 #ifndef CONFIG_DISCONTIGMEM
187 	/*
188 	 * Throw out ranges that are too far apart (controlled by
189 	 * MAX_GAP).
190 	 */
191 
192 	for (i = 1; i < npmem_ranges; i++) {
193 		if (pmem_ranges[i].start_pfn -
194 			(pmem_ranges[i-1].start_pfn +
195 			 pmem_ranges[i-1].pages) > MAX_GAP) {
196 			npmem_ranges = i;
197 			printk("Large gap in memory detected (%ld pages). "
198 			       "Consider turning on CONFIG_DISCONTIGMEM\n",
199 			       pmem_ranges[i].start_pfn -
200 			       (pmem_ranges[i-1].start_pfn +
201 			        pmem_ranges[i-1].pages));
202 			break;
203 		}
204 	}
205 #endif
206 
207 	/* Print the memory ranges */
208 	pr_info("Memory Ranges:\n");
209 
210 	for (i = 0; i < npmem_ranges; i++) {
211 		struct resource *res = &sysram_resources[i];
212 		unsigned long start;
213 		unsigned long size;
214 
215 		size = (pmem_ranges[i].pages << PAGE_SHIFT);
216 		start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
217 		pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
218 			i, start, start + (size - 1), size >> 20);
219 
220 		/* request memory resource */
221 		res->name = "System RAM";
222 		res->start = start;
223 		res->end = start + size - 1;
224 		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
225 		request_resource(&iomem_resource, res);
226 	}
227 
228 	sysram_resource_count = npmem_ranges;
229 
230 	/*
231 	 * For 32 bit kernels we limit the amount of memory we can
232 	 * support, in order to preserve enough kernel address space
233 	 * for other purposes. For 64 bit kernels we don't normally
234 	 * limit the memory, but this mechanism can be used to
235 	 * artificially limit the amount of memory (and it is written
236 	 * to work with multiple memory ranges).
237 	 */
238 
239 	mem_limit_func();       /* check for "mem=" argument */
240 
241 	mem_max = 0;
242 	for (i = 0; i < npmem_ranges; i++) {
243 		unsigned long rsize;
244 
245 		rsize = pmem_ranges[i].pages << PAGE_SHIFT;
246 		if ((mem_max + rsize) > mem_limit) {
247 			printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
248 			if (mem_max == mem_limit)
249 				npmem_ranges = i;
250 			else {
251 				pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
252 						       - (mem_max >> PAGE_SHIFT);
253 				npmem_ranges = i + 1;
254 				mem_max = mem_limit;
255 			}
256 			break;
257 		}
258 		mem_max += rsize;
259 	}
260 
261 	printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
262 
263 #ifndef CONFIG_DISCONTIGMEM
264 	/* Merge the ranges, keeping track of the holes */
265 
266 	{
267 		unsigned long end_pfn;
268 		unsigned long hole_pages;
269 
270 		npmem_holes = 0;
271 		end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
272 		for (i = 1; i < npmem_ranges; i++) {
273 
274 			hole_pages = pmem_ranges[i].start_pfn - end_pfn;
275 			if (hole_pages) {
276 				pmem_holes[npmem_holes].start_pfn = end_pfn;
277 				pmem_holes[npmem_holes++].pages = hole_pages;
278 				end_pfn += hole_pages;
279 			}
280 			end_pfn += pmem_ranges[i].pages;
281 		}
282 
283 		pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
284 		npmem_ranges = 1;
285 	}
286 #endif
287 
288 #ifdef CONFIG_DISCONTIGMEM
289 	for (i = 0; i < MAX_PHYSMEM_RANGES; i++) {
290 		memset(NODE_DATA(i), 0, sizeof(pg_data_t));
291 	}
292 	memset(pfnnid_map, 0xff, sizeof(pfnnid_map));
293 
294 	for (i = 0; i < npmem_ranges; i++) {
295 		node_set_state(i, N_NORMAL_MEMORY);
296 		node_set_online(i);
297 	}
298 #endif
299 
300 	/*
301 	 * Initialize and free the full range of memory in each range.
302 	 */
303 
304 	max_pfn = 0;
305 	for (i = 0; i < npmem_ranges; i++) {
306 		unsigned long start_pfn;
307 		unsigned long npages;
308 		unsigned long start;
309 		unsigned long size;
310 
311 		start_pfn = pmem_ranges[i].start_pfn;
312 		npages = pmem_ranges[i].pages;
313 
314 		start = start_pfn << PAGE_SHIFT;
315 		size = npages << PAGE_SHIFT;
316 
317 		/* add system RAM memblock */
318 		memblock_add(start, size);
319 
320 		if ((start_pfn + npages) > max_pfn)
321 			max_pfn = start_pfn + npages;
322 	}
323 
324 	/* IOMMU is always used to access "high mem" on those boxes
325 	 * that can support enough mem that a PCI device couldn't
326 	 * directly DMA to any physical addresses.
327 	 * ISA DMA support will need to revisit this.
328 	 */
329 	max_low_pfn = max_pfn;
330 
331 	/* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
332 
333 #define PDC_CONSOLE_IO_IODC_SIZE 32768
334 
335 	memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free +
336 				PDC_CONSOLE_IO_IODC_SIZE));
337 	memblock_reserve(__pa(KERNEL_BINARY_TEXT_START),
338 			(unsigned long)(_end - KERNEL_BINARY_TEXT_START));
339 
340 #ifndef CONFIG_DISCONTIGMEM
341 
342 	/* reserve the holes */
343 
344 	for (i = 0; i < npmem_holes; i++) {
345 		memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT),
346 				(pmem_holes[i].pages << PAGE_SHIFT));
347 	}
348 #endif
349 
350 #ifdef CONFIG_BLK_DEV_INITRD
351 	if (initrd_start) {
352 		printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
353 		if (__pa(initrd_start) < mem_max) {
354 			unsigned long initrd_reserve;
355 
356 			if (__pa(initrd_end) > mem_max) {
357 				initrd_reserve = mem_max - __pa(initrd_start);
358 			} else {
359 				initrd_reserve = initrd_end - initrd_start;
360 			}
361 			initrd_below_start_ok = 1;
362 			printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
363 
364 			memblock_reserve(__pa(initrd_start), initrd_reserve);
365 		}
366 	}
367 #endif
368 
369 	data_resource.start =  virt_to_phys(&data_start);
370 	data_resource.end = virt_to_phys(_end) - 1;
371 	code_resource.start = virt_to_phys(_text);
372 	code_resource.end = virt_to_phys(&data_start)-1;
373 
374 	/* We don't know which region the kernel will be in, so try
375 	 * all of them.
376 	 */
377 	for (i = 0; i < sysram_resource_count; i++) {
378 		struct resource *res = &sysram_resources[i];
379 		request_resource(res, &code_resource);
380 		request_resource(res, &data_resource);
381 	}
382 	request_resource(&sysram_resources[0], &pdcdata_resource);
383 
384 	/* Initialize Page Deallocation Table (PDT) and check for bad memory. */
385 	pdc_pdt_init();
386 }
387 
388 static int __init parisc_text_address(unsigned long vaddr)
389 {
390 	static unsigned long head_ptr __initdata;
391 
392 	if (!head_ptr)
393 		head_ptr = PAGE_MASK & (unsigned long)
394 			dereference_function_descriptor(&parisc_kernel_start);
395 
396 	return core_kernel_text(vaddr) || vaddr == head_ptr;
397 }
398 
399 static void __init map_pages(unsigned long start_vaddr,
400 			     unsigned long start_paddr, unsigned long size,
401 			     pgprot_t pgprot, int force)
402 {
403 	pgd_t *pg_dir;
404 	pmd_t *pmd;
405 	pte_t *pg_table;
406 	unsigned long end_paddr;
407 	unsigned long start_pmd;
408 	unsigned long start_pte;
409 	unsigned long tmp1;
410 	unsigned long tmp2;
411 	unsigned long address;
412 	unsigned long vaddr;
413 	unsigned long ro_start;
414 	unsigned long ro_end;
415 	unsigned long kernel_end;
416 
417 	ro_start = __pa((unsigned long)_text);
418 	ro_end   = __pa((unsigned long)&data_start);
419 	kernel_end  = __pa((unsigned long)&_end);
420 
421 	end_paddr = start_paddr + size;
422 
423 	pg_dir = pgd_offset_k(start_vaddr);
424 
425 #if PTRS_PER_PMD == 1
426 	start_pmd = 0;
427 #else
428 	start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
429 #endif
430 	start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
431 
432 	address = start_paddr;
433 	vaddr = start_vaddr;
434 	while (address < end_paddr) {
435 #if PTRS_PER_PMD == 1
436 		pmd = (pmd_t *)__pa(pg_dir);
437 #else
438 		pmd = (pmd_t *)pgd_address(*pg_dir);
439 
440 		/*
441 		 * pmd is physical at this point
442 		 */
443 
444 		if (!pmd) {
445 			pmd = (pmd_t *) get_memblock(PAGE_SIZE << PMD_ORDER);
446 			pmd = (pmd_t *) __pa(pmd);
447 		}
448 
449 		pgd_populate(NULL, pg_dir, __va(pmd));
450 #endif
451 		pg_dir++;
452 
453 		/* now change pmd to kernel virtual addresses */
454 
455 		pmd = (pmd_t *)__va(pmd) + start_pmd;
456 		for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) {
457 
458 			/*
459 			 * pg_table is physical at this point
460 			 */
461 
462 			pg_table = (pte_t *)pmd_address(*pmd);
463 			if (!pg_table) {
464 				pg_table = (pte_t *) get_memblock(PAGE_SIZE);
465 				pg_table = (pte_t *) __pa(pg_table);
466 			}
467 
468 			pmd_populate_kernel(NULL, pmd, __va(pg_table));
469 
470 			/* now change pg_table to kernel virtual addresses */
471 
472 			pg_table = (pte_t *) __va(pg_table) + start_pte;
473 			for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
474 				pte_t pte;
475 
476 				if (force)
477 					pte =  __mk_pte(address, pgprot);
478 				else if (parisc_text_address(vaddr)) {
479 					pte = __mk_pte(address, PAGE_KERNEL_EXEC);
480 					if (address >= ro_start && address < kernel_end)
481 						pte = pte_mkhuge(pte);
482 				}
483 				else
484 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
485 				if (address >= ro_start && address < ro_end) {
486 					pte = __mk_pte(address, PAGE_KERNEL_EXEC);
487 					pte = pte_mkhuge(pte);
488 				} else
489 #endif
490 				{
491 					pte = __mk_pte(address, pgprot);
492 					if (address >= ro_start && address < kernel_end)
493 						pte = pte_mkhuge(pte);
494 				}
495 
496 				if (address >= end_paddr)
497 					break;
498 
499 				set_pte(pg_table, pte);
500 
501 				address += PAGE_SIZE;
502 				vaddr += PAGE_SIZE;
503 			}
504 			start_pte = 0;
505 
506 			if (address >= end_paddr)
507 			    break;
508 		}
509 		start_pmd = 0;
510 	}
511 }
512 
513 void __init set_kernel_text_rw(int enable_read_write)
514 {
515 	unsigned long start = (unsigned long) _text;
516 	unsigned long end   = (unsigned long) &data_start;
517 
518 	map_pages(start, __pa(start), end-start,
519 		PAGE_KERNEL_RWX, enable_read_write ? 1:0);
520 
521 	/* force the kernel to see the new page table entries */
522 	flush_cache_all();
523 	flush_tlb_all();
524 }
525 
526 void __ref free_initmem(void)
527 {
528 	unsigned long init_begin = (unsigned long)__init_begin;
529 	unsigned long init_end = (unsigned long)__init_end;
530 
531 	/* The init text pages are marked R-X.  We have to
532 	 * flush the icache and mark them RW-
533 	 *
534 	 * This is tricky, because map_pages is in the init section.
535 	 * Do a dummy remap of the data section first (the data
536 	 * section is already PAGE_KERNEL) to pull in the TLB entries
537 	 * for map_kernel */
538 	map_pages(init_begin, __pa(init_begin), init_end - init_begin,
539 		  PAGE_KERNEL_RWX, 1);
540 	/* now remap at PAGE_KERNEL since the TLB is pre-primed to execute
541 	 * map_pages */
542 	map_pages(init_begin, __pa(init_begin), init_end - init_begin,
543 		  PAGE_KERNEL, 1);
544 
545 	/* force the kernel to see the new TLB entries */
546 	__flush_tlb_range(0, init_begin, init_end);
547 
548 	/* finally dump all the instructions which were cached, since the
549 	 * pages are no-longer executable */
550 	flush_icache_range(init_begin, init_end);
551 
552 	free_initmem_default(POISON_FREE_INITMEM);
553 
554 	/* set up a new led state on systems shipped LED State panel */
555 	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
556 }
557 
558 
559 #ifdef CONFIG_STRICT_KERNEL_RWX
560 void mark_rodata_ro(void)
561 {
562 	/* rodata memory was already mapped with KERNEL_RO access rights by
563            pagetable_init() and map_pages(). No need to do additional stuff here */
564 	printk (KERN_INFO "Write protecting the kernel read-only data: %luk\n",
565 		(unsigned long)(__end_rodata - __start_rodata) >> 10);
566 }
567 #endif
568 
569 
570 /*
571  * Just an arbitrary offset to serve as a "hole" between mapping areas
572  * (between top of physical memory and a potential pcxl dma mapping
573  * area, and below the vmalloc mapping area).
574  *
575  * The current 32K value just means that there will be a 32K "hole"
576  * between mapping areas. That means that  any out-of-bounds memory
577  * accesses will hopefully be caught. The vmalloc() routines leaves
578  * a hole of 4kB between each vmalloced area for the same reason.
579  */
580 
581  /* Leave room for gateway page expansion */
582 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
583 #error KERNEL_MAP_START is in gateway reserved region
584 #endif
585 #define MAP_START (KERNEL_MAP_START)
586 
587 #define VM_MAP_OFFSET  (32*1024)
588 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
589 				     & ~(VM_MAP_OFFSET-1)))
590 
591 void *parisc_vmalloc_start __read_mostly;
592 EXPORT_SYMBOL(parisc_vmalloc_start);
593 
594 #ifdef CONFIG_PA11
595 unsigned long pcxl_dma_start __read_mostly;
596 #endif
597 
598 void __init mem_init(void)
599 {
600 	/* Do sanity checks on IPC (compat) structures */
601 	BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48);
602 #ifndef CONFIG_64BIT
603 	BUILD_BUG_ON(sizeof(struct semid64_ds) != 80);
604 	BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104);
605 	BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104);
606 #endif
607 #ifdef CONFIG_COMPAT
608 	BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm));
609 	BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80);
610 	BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104);
611 	BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104);
612 #endif
613 
614 	/* Do sanity checks on page table constants */
615 	BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t));
616 	BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t));
617 	BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t));
618 	BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD
619 			> BITS_PER_LONG);
620 
621 	high_memory = __va((max_pfn << PAGE_SHIFT));
622 	set_max_mapnr(page_to_pfn(virt_to_page(high_memory - 1)) + 1);
623 	memblock_free_all();
624 
625 #ifdef CONFIG_PA11
626 	if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
627 		pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
628 		parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start
629 						+ PCXL_DMA_MAP_SIZE);
630 	} else
631 #endif
632 		parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
633 
634 	mem_init_print_info(NULL);
635 
636 #if 0
637 	/*
638 	 * Do not expose the virtual kernel memory layout to userspace.
639 	 * But keep code for debugging purposes.
640 	 */
641 	printk("virtual kernel memory layout:\n"
642 	       "    vmalloc : 0x%px - 0x%px   (%4ld MB)\n"
643 	       "    memory  : 0x%px - 0x%px   (%4ld MB)\n"
644 	       "      .init : 0x%px - 0x%px   (%4ld kB)\n"
645 	       "      .data : 0x%px - 0x%px   (%4ld kB)\n"
646 	       "      .text : 0x%px - 0x%px   (%4ld kB)\n",
647 
648 	       (void*)VMALLOC_START, (void*)VMALLOC_END,
649 	       (VMALLOC_END - VMALLOC_START) >> 20,
650 
651 	       __va(0), high_memory,
652 	       ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
653 
654 	       __init_begin, __init_end,
655 	       ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
656 
657 	       _etext, _edata,
658 	       ((unsigned long)_edata - (unsigned long)_etext) >> 10,
659 
660 	       _text, _etext,
661 	       ((unsigned long)_etext - (unsigned long)_text) >> 10);
662 #endif
663 }
664 
665 unsigned long *empty_zero_page __read_mostly;
666 EXPORT_SYMBOL(empty_zero_page);
667 
668 /*
669  * pagetable_init() sets up the page tables
670  *
671  * Note that gateway_init() places the Linux gateway page at page 0.
672  * Since gateway pages cannot be dereferenced this has the desirable
673  * side effect of trapping those pesky NULL-reference errors in the
674  * kernel.
675  */
676 static void __init pagetable_init(void)
677 {
678 	int range;
679 
680 	/* Map each physical memory range to its kernel vaddr */
681 
682 	for (range = 0; range < npmem_ranges; range++) {
683 		unsigned long start_paddr;
684 		unsigned long end_paddr;
685 		unsigned long size;
686 
687 		start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
688 		size = pmem_ranges[range].pages << PAGE_SHIFT;
689 		end_paddr = start_paddr + size;
690 
691 		map_pages((unsigned long)__va(start_paddr), start_paddr,
692 			  size, PAGE_KERNEL, 0);
693 	}
694 
695 #ifdef CONFIG_BLK_DEV_INITRD
696 	if (initrd_end && initrd_end > mem_limit) {
697 		printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
698 		map_pages(initrd_start, __pa(initrd_start),
699 			  initrd_end - initrd_start, PAGE_KERNEL, 0);
700 	}
701 #endif
702 
703 	empty_zero_page = get_memblock(PAGE_SIZE);
704 }
705 
706 static void __init gateway_init(void)
707 {
708 	unsigned long linux_gateway_page_addr;
709 	/* FIXME: This is 'const' in order to trick the compiler
710 	   into not treating it as DP-relative data. */
711 	extern void * const linux_gateway_page;
712 
713 	linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
714 
715 	/*
716 	 * Setup Linux Gateway page.
717 	 *
718 	 * The Linux gateway page will reside in kernel space (on virtual
719 	 * page 0), so it doesn't need to be aliased into user space.
720 	 */
721 
722 	map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
723 		  PAGE_SIZE, PAGE_GATEWAY, 1);
724 }
725 
726 void __init paging_init(void)
727 {
728 	int i;
729 
730 	setup_bootmem();
731 	pagetable_init();
732 	gateway_init();
733 	flush_cache_all_local(); /* start with known state */
734 	flush_tlb_all_local(NULL);
735 
736 	for (i = 0; i < npmem_ranges; i++) {
737 		unsigned long zones_size[MAX_NR_ZONES] = { 0, };
738 
739 		zones_size[ZONE_NORMAL] = pmem_ranges[i].pages;
740 
741 #ifdef CONFIG_DISCONTIGMEM
742 		/* Need to initialize the pfnnid_map before we can initialize
743 		   the zone */
744 		{
745 		    int j;
746 		    for (j = (pmem_ranges[i].start_pfn >> PFNNID_SHIFT);
747 			 j <= ((pmem_ranges[i].start_pfn + pmem_ranges[i].pages) >> PFNNID_SHIFT);
748 			 j++) {
749 			pfnnid_map[j] = i;
750 		    }
751 		}
752 #endif
753 
754 		free_area_init_node(i, zones_size,
755 				pmem_ranges[i].start_pfn, NULL);
756 	}
757 }
758 
759 #ifdef CONFIG_PA20
760 
761 /*
762  * Currently, all PA20 chips have 18 bit protection IDs, which is the
763  * limiting factor (space ids are 32 bits).
764  */
765 
766 #define NR_SPACE_IDS 262144
767 
768 #else
769 
770 /*
771  * Currently we have a one-to-one relationship between space IDs and
772  * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
773  * support 15 bit protection IDs, so that is the limiting factor.
774  * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
775  * probably not worth the effort for a special case here.
776  */
777 
778 #define NR_SPACE_IDS 32768
779 
780 #endif  /* !CONFIG_PA20 */
781 
782 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
783 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
784 
785 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
786 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
787 static unsigned long space_id_index;
788 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
789 static unsigned long dirty_space_ids = 0;
790 
791 static DEFINE_SPINLOCK(sid_lock);
792 
793 unsigned long alloc_sid(void)
794 {
795 	unsigned long index;
796 
797 	spin_lock(&sid_lock);
798 
799 	if (free_space_ids == 0) {
800 		if (dirty_space_ids != 0) {
801 			spin_unlock(&sid_lock);
802 			flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
803 			spin_lock(&sid_lock);
804 		}
805 		BUG_ON(free_space_ids == 0);
806 	}
807 
808 	free_space_ids--;
809 
810 	index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
811 	space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
812 	space_id_index = index;
813 
814 	spin_unlock(&sid_lock);
815 
816 	return index << SPACEID_SHIFT;
817 }
818 
819 void free_sid(unsigned long spaceid)
820 {
821 	unsigned long index = spaceid >> SPACEID_SHIFT;
822 	unsigned long *dirty_space_offset;
823 
824 	dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
825 	index &= (BITS_PER_LONG - 1);
826 
827 	spin_lock(&sid_lock);
828 
829 	BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */
830 
831 	*dirty_space_offset |= (1L << index);
832 	dirty_space_ids++;
833 
834 	spin_unlock(&sid_lock);
835 }
836 
837 
838 #ifdef CONFIG_SMP
839 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
840 {
841 	int i;
842 
843 	/* NOTE: sid_lock must be held upon entry */
844 
845 	*ndirtyptr = dirty_space_ids;
846 	if (dirty_space_ids != 0) {
847 	    for (i = 0; i < SID_ARRAY_SIZE; i++) {
848 		dirty_array[i] = dirty_space_id[i];
849 		dirty_space_id[i] = 0;
850 	    }
851 	    dirty_space_ids = 0;
852 	}
853 
854 	return;
855 }
856 
857 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
858 {
859 	int i;
860 
861 	/* NOTE: sid_lock must be held upon entry */
862 
863 	if (ndirty != 0) {
864 		for (i = 0; i < SID_ARRAY_SIZE; i++) {
865 			space_id[i] ^= dirty_array[i];
866 		}
867 
868 		free_space_ids += ndirty;
869 		space_id_index = 0;
870 	}
871 }
872 
873 #else /* CONFIG_SMP */
874 
875 static void recycle_sids(void)
876 {
877 	int i;
878 
879 	/* NOTE: sid_lock must be held upon entry */
880 
881 	if (dirty_space_ids != 0) {
882 		for (i = 0; i < SID_ARRAY_SIZE; i++) {
883 			space_id[i] ^= dirty_space_id[i];
884 			dirty_space_id[i] = 0;
885 		}
886 
887 		free_space_ids += dirty_space_ids;
888 		dirty_space_ids = 0;
889 		space_id_index = 0;
890 	}
891 }
892 #endif
893 
894 /*
895  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
896  * purged, we can safely reuse the space ids that were released but
897  * not flushed from the tlb.
898  */
899 
900 #ifdef CONFIG_SMP
901 
902 static unsigned long recycle_ndirty;
903 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
904 static unsigned int recycle_inuse;
905 
906 void flush_tlb_all(void)
907 {
908 	int do_recycle;
909 
910 	__inc_irq_stat(irq_tlb_count);
911 	do_recycle = 0;
912 	spin_lock(&sid_lock);
913 	if (dirty_space_ids > RECYCLE_THRESHOLD) {
914 	    BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
915 	    get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
916 	    recycle_inuse++;
917 	    do_recycle++;
918 	}
919 	spin_unlock(&sid_lock);
920 	on_each_cpu(flush_tlb_all_local, NULL, 1);
921 	if (do_recycle) {
922 	    spin_lock(&sid_lock);
923 	    recycle_sids(recycle_ndirty,recycle_dirty_array);
924 	    recycle_inuse = 0;
925 	    spin_unlock(&sid_lock);
926 	}
927 }
928 #else
929 void flush_tlb_all(void)
930 {
931 	__inc_irq_stat(irq_tlb_count);
932 	spin_lock(&sid_lock);
933 	flush_tlb_all_local(NULL);
934 	recycle_sids();
935 	spin_unlock(&sid_lock);
936 }
937 #endif
938 
939 #ifdef CONFIG_BLK_DEV_INITRD
940 void free_initrd_mem(unsigned long start, unsigned long end)
941 {
942 	free_reserved_area((void *)start, (void *)end, -1, "initrd");
943 }
944 #endif
945