1 // SPDX-License-Identifier: GPL-2.0-only
3 * linux/arch/sh/mm/init.c
5 * Copyright (C) 1999 Niibe Yutaka
6 * Copyright (C) 2002 - 2011 Paul Mundt
8 * Based on linux/arch/i386/mm/init.c:
9 * Copyright (C) 1995 Linus Torvalds
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>
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>
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>
34 pgd_t swapper_pg_dir[PTRS_PER_PGD];
36 void __init generic_mem_init(void)
38 memblock_add(__MEMORY_START, __MEMORY_SIZE);
41 void __init __weak plat_mem_setup(void)
43 /* Nothing to see here, move along. */
47 static pte_t *__get_pte_phys(unsigned long addr)
54 pgd = pgd_offset_k(addr);
60 p4d = p4d_alloc(NULL, pgd, addr);
66 pud = pud_alloc(NULL, p4d, addr);
72 pmd = pmd_alloc(NULL, pud, addr);
78 return pte_offset_kernel(pmd, addr);
81 static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
85 pte = __get_pte_phys(addr);
86 if (!pte_none(*pte)) {
91 set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
92 local_flush_tlb_one(get_asid(), addr);
94 if (pgprot_val(prot) & _PAGE_WIRED)
95 tlb_wire_entry(NULL, addr, *pte);
98 static void clear_pte_phys(unsigned long addr, pgprot_t prot)
102 pte = __get_pte_phys(addr);
104 if (pgprot_val(prot) & _PAGE_WIRED)
107 set_pte(pte, pfn_pte(0, __pgprot(0)));
108 local_flush_tlb_one(get_asid(), addr);
111 void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
113 unsigned long address = __fix_to_virt(idx);
115 if (idx >= __end_of_fixed_addresses) {
120 set_pte_phys(address, phys, prot);
123 void __clear_fixmap(enum fixed_addresses idx, pgprot_t prot)
125 unsigned long address = __fix_to_virt(idx);
127 if (idx >= __end_of_fixed_addresses) {
132 clear_pte_phys(address, prot);
135 static pmd_t * __init one_md_table_init(pud_t *pud)
137 if (pud_none(*pud)) {
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));
145 return pmd_offset(pud, 0);
148 static pte_t * __init one_page_table_init(pmd_t *pmd)
150 if (pmd_none(*pmd)) {
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));
158 return pte_offset_kernel(pmd, 0);
161 static pte_t * __init page_table_kmap_check(pte_t *pte, pmd_t *pmd,
162 unsigned long vaddr, pte_t *lastpte)
167 void __init page_table_range_init(unsigned long start, unsigned long end,
178 i = pgd_index(vaddr);
179 j = pud_index(vaddr);
180 k = pmd_index(vaddr);
183 for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
185 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
186 pmd = one_md_table_init(pud);
187 #ifndef __PAGETABLE_PMD_FOLDED
190 for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
191 pte = page_table_kmap_check(one_page_table_init(pmd),
200 #endif /* CONFIG_MMU */
202 void __init allocate_pgdat(unsigned int nid)
204 unsigned long start_pfn, end_pfn;
206 get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
209 alloc_node_data(nid);
212 NODE_DATA(nid)->node_start_pfn = start_pfn;
213 NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
216 static void __init do_init_bootmem(void)
218 unsigned long start_pfn, end_pfn;
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);
225 /* All of system RAM sits in node 0 for the non-NUMA case */
234 static void __init early_reserve_mem(void)
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;
241 * Partially used pages are not usable - thus
242 * we are rounding upwards:
244 start_pfn = PFN_UP(__pa(_end));
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.
252 memblock_reserve(start, (PFN_PHYS(start_pfn) + PAGE_SIZE - 1) - start);
255 * Reserve physical pages below CONFIG_ZERO_PAGE_OFFSET.
257 if (CONFIG_ZERO_PAGE_OFFSET != 0)
258 memblock_reserve(zero_base, CONFIG_ZERO_PAGE_OFFSET);
261 * Handle additional early reservations
264 reserve_crashkernel();
267 void __init paging_init(void)
269 unsigned long max_zone_pfns[MAX_NR_ZONES];
270 unsigned long vaddr, end;
277 * Once the early reservations are out of the way, give the
278 * platforms a chance to kick out some memory.
280 if (sh_mv.mv_mem_reserve)
281 sh_mv.mv_mem_reserve();
283 memblock_enforce_memory_limit(memory_limit);
284 memblock_allow_resize();
289 * Determine low and high memory ranges:
291 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
292 min_low_pfn = __MEMORY_START >> PAGE_SHIFT;
294 nodes_clear(node_online_map);
296 memory_start = (unsigned long)__va(__MEMORY_START);
297 memory_end = memory_start + (memory_limit ?: memblock_phys_mem_size());
302 ioremap_fixed_init();
304 /* We don't need to map the kernel through the TLB, as
305 * it is permanatly mapped using P1. So clear the
307 memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
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);
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().
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);
322 kmap_coherent_init();
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);
329 unsigned int mem_init_done = 0;
331 void __init mem_init(void)
333 /* Set this up early, so we can take care of the zero page */
336 /* clear the zero-page */
337 memset(empty_zero_page, 0, PAGE_SIZE);
338 __flush_wback_region(empty_zero_page, PAGE_SIZE);
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"
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,
355 (unsigned long)VMALLOC_START, VMALLOC_END,
356 (VMALLOC_END - VMALLOC_START) >> 20,
358 (unsigned long)memory_start, (unsigned long)high_memory,
359 ((unsigned long)high_memory - (unsigned long)memory_start) >> 20,
361 #ifdef CONFIG_UNCACHED_MAPPING
362 uncached_start, uncached_end, uncached_size >> 20,
365 (unsigned long)&__init_begin, (unsigned long)&__init_end,
366 ((unsigned long)&__init_end -
367 (unsigned long)&__init_begin) >> 10,
369 (unsigned long)&_etext, (unsigned long)&_edata,
370 ((unsigned long)&_edata - (unsigned long)&_etext) >> 10,
372 (unsigned long)&_text, (unsigned long)&_etext,
373 ((unsigned long)&_etext - (unsigned long)&_text) >> 10);