init.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * linux/arch/sh/mm/init.c
  4 *
  5 *  Copyright (C) 1999  Niibe Yutaka
  6 *  Copyright (C) 2002 - 2011  Paul Mundt
  7 *
  8 *  Based on linux/arch/i386/mm/init.c:
  9 *   Copyright (C) 1995  Linus Torvalds
 10 */
 11#include <linux/mm.h>
 12#include <linux/swap.h>
 13#include <linux/init.h>
 14#include <linux/gfp.h>
 15#include <linux/memblock.h>
 16#include <linux/proc_fs.h>
 17#include <linux/pagemap.h>
 18#include <linux/percpu.h>
 19#include <linux/io.h>
 20#include <linux/dma-mapping.h>
 21#include <linux/export.h>
 22#include <asm/mmu_context.h>
 23#include <asm/mmzone.h>
 24#include <asm/kexec.h>
 25#include <asm/tlb.h>
 26#include <asm/cacheflush.h>
 27#include <asm/sections.h>
 28#include <asm/setup.h>
 29#include <asm/cache.h>
 30#include <asm/pgalloc.h>
 31#include <linux/sizes.h>
 32#include "ioremap.h"
 33
 34pgd_t swapper_pg_dir[PTRS_PER_PGD];
 35
 36void __init generic_mem_init(void)
 37{
 38	memblock_add(__MEMORY_START, __MEMORY_SIZE);
 39}
 40
 41void __init __weak plat_mem_setup(void)
 42{
 43	/* Nothing to see here, move along. */
 44}
 45
 46#ifdef CONFIG_MMU
 47static pte_t *__get_pte_phys(unsigned long addr)
 48{
 49	pgd_t *pgd;
 50	p4d_t *p4d;
 51	pud_t *pud;
 52	pmd_t *pmd;
 53
 54	pgd = pgd_offset_k(addr);
 55	if (pgd_none(*pgd)) {
 56		pgd_ERROR(*pgd);
 57		return NULL;
 58	}
 59
 60	p4d = p4d_alloc(NULL, pgd, addr);
 61	if (unlikely(!p4d)) {
 62		p4d_ERROR(*p4d);
 63		return NULL;
 64	}
 65
 66	pud = pud_alloc(NULL, p4d, addr);
 67	if (unlikely(!pud)) {
 68		pud_ERROR(*pud);
 69		return NULL;
 70	}
 71
 72	pmd = pmd_alloc(NULL, pud, addr);
 73	if (unlikely(!pmd)) {
 74		pmd_ERROR(*pmd);
 75		return NULL;
 76	}
 77
 78	return pte_offset_kernel(pmd, addr);
 79}
 80
 81static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
 82{
 83	pte_t *pte;
 84
 85	pte = __get_pte_phys(addr);
 86	if (!pte_none(*pte)) {
 87		pte_ERROR(*pte);
 88		return;
 89	}
 90
 91	set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
 92	local_flush_tlb_one(get_asid(), addr);
 93
 94	if (pgprot_val(prot) & _PAGE_WIRED)
 95		tlb_wire_entry(NULL, addr, *pte);
 96}
 97
 98static void clear_pte_phys(unsigned long addr, pgprot_t prot)
 99{
100	pte_t *pte;
101
102	pte = __get_pte_phys(addr);
103
104	if (pgprot_val(prot) & _PAGE_WIRED)
105		tlb_unwire_entry();
106
107	set_pte(pte, pfn_pte(0, __pgprot(0)));
108	local_flush_tlb_one(get_asid(), addr);
109}
110
111void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
112{
113	unsigned long address = __fix_to_virt(idx);
114
115	if (idx >= __end_of_fixed_addresses) {
116		BUG();
117		return;
118	}
119
120	set_pte_phys(address, phys, prot);
121}
122
123void __clear_fixmap(enum fixed_addresses idx, pgprot_t prot)
124{
125	unsigned long address = __fix_to_virt(idx);
126
127	if (idx >= __end_of_fixed_addresses) {
128		BUG();
129		return;
130	}
131
132	clear_pte_phys(address, prot);
133}
134
135static pmd_t * __init one_md_table_init(pud_t *pud)
136{
137	if (pud_none(*pud)) {
138		pmd_t *pmd;
139
140		pmd = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
141		pud_populate(&init_mm, pud, pmd);
142		BUG_ON(pmd != pmd_offset(pud, 0));
143	}
144
145	return pmd_offset(pud, 0);
146}
147
148static pte_t * __init one_page_table_init(pmd_t *pmd)
149{
150	if (pmd_none(*pmd)) {
151		pte_t *pte;
152
153		pte = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
154		pmd_populate_kernel(&init_mm, pmd, pte);
155		BUG_ON(pte != pte_offset_kernel(pmd, 0));
156	}
157
158	return pte_offset_kernel(pmd, 0);
159}
160
161static pte_t * __init page_table_kmap_check(pte_t *pte, pmd_t *pmd,
162					    unsigned long vaddr, pte_t *lastpte)
163{
164	return pte;
165}
166
167void __init page_table_range_init(unsigned long start, unsigned long end,
168					 pgd_t *pgd_base)
169{
170	pgd_t *pgd;
171	pud_t *pud;
172	pmd_t *pmd;
173	pte_t *pte = NULL;
174	int i, j, k;
175	unsigned long vaddr;
176
177	vaddr = start;
178	i = pgd_index(vaddr);
179	j = pud_index(vaddr);
180	k = pmd_index(vaddr);
181	pgd = pgd_base + i;
182
183	for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
184		pud = (pud_t *)pgd;
185		for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
186			pmd = one_md_table_init(pud);
187#ifndef __PAGETABLE_PMD_FOLDED
188			pmd += k;
189#endif
190			for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
191				pte = page_table_kmap_check(one_page_table_init(pmd),
192							    pmd, vaddr, pte);
193				vaddr += PMD_SIZE;
194			}
195			k = 0;
196		}
197		j = 0;
198	}
199}
200#endif	/* CONFIG_MMU */
201
202void __init allocate_pgdat(unsigned int nid)
203{
204	unsigned long start_pfn, end_pfn;
205
206	get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
207
208#ifdef CONFIG_NUMA
209	alloc_node_data(nid);
210#endif
211
212	NODE_DATA(nid)->node_start_pfn = start_pfn;
213	NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
214}
215
216static void __init do_init_bootmem(void)
217{
218	unsigned long start_pfn, end_pfn;
219	int i;
220
221	/* Add active regions with valid PFNs. */
222	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL)
223		__add_active_range(0, start_pfn, end_pfn);
224
225	/* All of system RAM sits in node 0 for the non-NUMA case */
226	allocate_pgdat(0);
227	node_set_online(0);
228
229	plat_mem_setup();
230
231	sparse_init();
232}
233
234static void __init early_reserve_mem(void)
235{
236	unsigned long start_pfn;
237	u32 zero_base = (u32)__MEMORY_START + (u32)PHYSICAL_OFFSET;
238	u32 start = zero_base + (u32)CONFIG_ZERO_PAGE_OFFSET;
239
240	/*
241	 * Partially used pages are not usable - thus
242	 * we are rounding upwards:
243	 */
244	start_pfn = PFN_UP(__pa(_end));
245
246	/*
247	 * Reserve the kernel text and Reserve the bootmem bitmap. We do
248	 * this in two steps (first step was init_bootmem()), because
249	 * this catches the (definitely buggy) case of us accidentally
250	 * initializing the bootmem allocator with an invalid RAM area.
251	 */
252	memblock_reserve(start, (PFN_PHYS(start_pfn) + PAGE_SIZE - 1) - start);
253
254	/*
255	 * Reserve physical pages below CONFIG_ZERO_PAGE_OFFSET.
256	 */
257	if (CONFIG_ZERO_PAGE_OFFSET != 0)
258		memblock_reserve(zero_base, CONFIG_ZERO_PAGE_OFFSET);
259
260	/*
261	 * Handle additional early reservations
262	 */
263	check_for_initrd();
264	reserve_crashkernel();
265}
266
267void __init paging_init(void)
268{
269	unsigned long max_zone_pfns[MAX_NR_ZONES];
270	unsigned long vaddr, end;
271
272	sh_mv.mv_mem_init();
273
274	early_reserve_mem();
275
276	/*
277	 * Once the early reservations are out of the way, give the
278	 * platforms a chance to kick out some memory.
279	 */
280	if (sh_mv.mv_mem_reserve)
281		sh_mv.mv_mem_reserve();
282
283	memblock_enforce_memory_limit(memory_limit);
284	memblock_allow_resize();
285
286	memblock_dump_all();
287
288	/*
289	 * Determine low and high memory ranges:
290	 */
291	max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
292	min_low_pfn = __MEMORY_START >> PAGE_SHIFT;
293
294	nodes_clear(node_online_map);
295
296	memory_start = (unsigned long)__va(__MEMORY_START);
297	memory_end = memory_start + (memory_limit ?: memblock_phys_mem_size());
298
299	uncached_init();
300	pmb_init();
301	do_init_bootmem();
302	ioremap_fixed_init();
303
304	/* We don't need to map the kernel through the TLB, as
305	 * it is permanatly mapped using P1. So clear the
306	 * entire pgd. */
307	memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
308
309	/* Set an initial value for the MMU.TTB so we don't have to
310	 * check for a null value. */
311	set_TTB(swapper_pg_dir);
312
313	/*
314	 * Populate the relevant portions of swapper_pg_dir so that
315	 * we can use the fixmap entries without calling kmalloc.
316	 * pte's will be filled in by __set_fixmap().
317	 */
318	vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
319	end = (FIXADDR_TOP + PMD_SIZE - 1) & PMD_MASK;
320	page_table_range_init(vaddr, end, swapper_pg_dir);
321
322	kmap_coherent_init();
323
324	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
325	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
326	free_area_init(max_zone_pfns);
327}
328
329unsigned int mem_init_done = 0;
330
331void __init mem_init(void)
332{
333	/* Set this up early, so we can take care of the zero page */
334	cpu_cache_init();
335
336	/* clear the zero-page */
337	memset(empty_zero_page, 0, PAGE_SIZE);
338	__flush_wback_region(empty_zero_page, PAGE_SIZE);
339
340	vsyscall_init();
341
342	pr_info("virtual kernel memory layout:\n"
343		"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
344		"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
345		"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB) (cached)\n"
346#ifdef CONFIG_UNCACHED_MAPPING
347		"            : 0x%08lx - 0x%08lx   (%4ld MB) (uncached)\n"
348#endif
349		"      .init : 0x%08lx - 0x%08lx   (%4ld kB)\n"
350		"      .data : 0x%08lx - 0x%08lx   (%4ld kB)\n"
351		"      .text : 0x%08lx - 0x%08lx   (%4ld kB)\n",
352		FIXADDR_START, FIXADDR_TOP,
353		(FIXADDR_TOP - FIXADDR_START) >> 10,
354
355		(unsigned long)VMALLOC_START, VMALLOC_END,
356		(VMALLOC_END - VMALLOC_START) >> 20,
357
358		(unsigned long)memory_start, (unsigned long)high_memory,
359		((unsigned long)high_memory - (unsigned long)memory_start) >> 20,
360
361#ifdef CONFIG_UNCACHED_MAPPING
362		uncached_start, uncached_end, uncached_size >> 20,
363#endif
364
365		(unsigned long)&__init_begin, (unsigned long)&__init_end,
366		((unsigned long)&__init_end -
367		 (unsigned long)&__init_begin) >> 10,
368
369		(unsigned long)&_etext, (unsigned long)&_edata,
370		((unsigned long)&_edata - (unsigned long)&_etext) >> 10,
371
372		(unsigned long)&_text, (unsigned long)&_etext,
373		((unsigned long)&_etext - (unsigned long)&_text) >> 10);
374
375	mem_init_done = 1;
376}