1 // SPDX-License-Identifier: GPL-2.0
3 * linux/arch/sparc/mm/init.c
5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
6 * Copyright (C) 1995 Eddie C. Dost (ecd@skynet.be)
7 * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
8 * Copyright (C) 2000 Anton Blanchard (anton@samba.org)
11 #include <linux/module.h>
12 #include <linux/signal.h>
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/string.h>
17 #include <linux/types.h>
18 #include <linux/ptrace.h>
19 #include <linux/mman.h>
21 #include <linux/swap.h>
22 #include <linux/initrd.h>
23 #include <linux/init.h>
24 #include <linux/highmem.h>
25 #include <linux/bootmem.h>
26 #include <linux/memblock.h>
27 #include <linux/pagemap.h>
28 #include <linux/poison.h>
29 #include <linux/gfp.h>
31 #include <asm/sections.h>
33 #include <asm/pgtable.h>
34 #include <asm/vaddrs.h>
35 #include <asm/pgalloc.h> /* bug in asm-generic/tlb.h: check_pgt_cache */
36 #include <asm/setup.h>
43 unsigned long *sparc_valid_addr_bitmap;
44 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
46 unsigned long phys_base;
47 EXPORT_SYMBOL(phys_base);
49 unsigned long pfn_base;
50 EXPORT_SYMBOL(pfn_base);
52 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
54 /* Initial ramdisk setup */
55 extern unsigned int sparc_ramdisk_image;
56 extern unsigned int sparc_ramdisk_size;
58 unsigned long highstart_pfn, highend_pfn;
60 unsigned long last_valid_pfn;
62 unsigned long calc_highpages(void)
67 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
68 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
69 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
71 if (end_pfn <= max_low_pfn)
74 if (start_pfn < max_low_pfn)
75 start_pfn = max_low_pfn;
77 nr += end_pfn - start_pfn;
83 static unsigned long calc_max_low_pfn(void)
86 unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
87 unsigned long curr_pfn, last_pfn;
89 last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
90 for (i = 1; sp_banks[i].num_bytes != 0; i++) {
91 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
93 if (curr_pfn >= tmp) {
99 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
105 static void __init find_ramdisk(unsigned long end_of_phys_memory)
107 #ifdef CONFIG_BLK_DEV_INITRD
110 /* Now have to check initial ramdisk, so that it won't pass
113 if (sparc_ramdisk_image) {
114 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
115 sparc_ramdisk_image -= KERNBASE;
116 initrd_start = sparc_ramdisk_image + phys_base;
117 initrd_end = initrd_start + sparc_ramdisk_size;
118 if (initrd_end > end_of_phys_memory) {
119 printk(KERN_CRIT "initrd extends beyond end of memory "
120 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
121 initrd_end, end_of_phys_memory);
124 /* Reserve the initrd image area. */
125 size = initrd_end - initrd_start;
126 memblock_reserve(initrd_start, size);
128 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
129 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
135 unsigned long __init bootmem_init(unsigned long *pages_avail)
137 unsigned long start_pfn, bytes_avail, size;
138 unsigned long end_of_phys_memory = 0;
139 unsigned long high_pages = 0;
142 memblock_set_bottom_up(true);
143 memblock_allow_resize();
146 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
147 end_of_phys_memory = sp_banks[i].base_addr +
148 sp_banks[i].num_bytes;
149 bytes_avail += sp_banks[i].num_bytes;
150 if (cmdline_memory_size) {
151 if (bytes_avail > cmdline_memory_size) {
152 unsigned long slack = bytes_avail - cmdline_memory_size;
154 bytes_avail -= slack;
155 end_of_phys_memory -= slack;
157 sp_banks[i].num_bytes -= slack;
158 if (sp_banks[i].num_bytes == 0) {
159 sp_banks[i].base_addr = 0xdeadbeef;
161 memblock_add(sp_banks[i].base_addr,
162 sp_banks[i].num_bytes);
163 sp_banks[i+1].num_bytes = 0;
164 sp_banks[i+1].base_addr = 0xdeadbeef;
169 memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes);
172 /* Start with page aligned address of last symbol in kernel
175 start_pfn = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
177 /* Now shift down to get the real physical page frame number. */
178 start_pfn >>= PAGE_SHIFT;
180 max_pfn = end_of_phys_memory >> PAGE_SHIFT;
182 max_low_pfn = max_pfn;
183 highstart_pfn = highend_pfn = max_pfn;
185 if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
186 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
187 max_low_pfn = calc_max_low_pfn();
188 high_pages = calc_highpages();
189 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
190 high_pages >> (20 - PAGE_SHIFT));
193 find_ramdisk(end_of_phys_memory);
195 /* Reserve the kernel text/data/bss. */
196 size = (start_pfn << PAGE_SHIFT) - phys_base;
197 memblock_reserve(phys_base, size);
199 size = memblock_phys_mem_size() - memblock_reserved_size();
200 *pages_avail = (size >> PAGE_SHIFT) - high_pages;
202 /* Only allow low memory to be allocated via memblock allocation */
203 memblock_set_current_limit(max_low_pfn << PAGE_SHIFT);
209 * paging_init() sets up the page tables: We call the MMU specific
210 * init routine based upon the Sun model type on the Sparc.
213 void __init paging_init(void)
216 prom_build_devicetree();
217 of_fill_in_cpu_data();
221 static void __init taint_real_pages(void)
225 for (i = 0; sp_banks[i].num_bytes; i++) {
226 unsigned long start, end;
228 start = sp_banks[i].base_addr;
229 end = start + sp_banks[i].num_bytes;
231 while (start < end) {
232 set_bit(start >> 20, sparc_valid_addr_bitmap);
238 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
242 #ifdef CONFIG_DEBUG_HIGHMEM
243 printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
246 for (tmp = start_pfn; tmp < end_pfn; tmp++)
247 free_highmem_page(pfn_to_page(tmp));
250 void __init mem_init(void)
254 if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
255 prom_printf("BUG: fixmap and pkmap areas overlap\n");
256 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
258 (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
260 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
265 /* Saves us work later. */
266 memset((void *)empty_zero_page, 0, PAGE_SIZE);
268 i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
270 sparc_valid_addr_bitmap = (unsigned long *)
271 __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
273 if (sparc_valid_addr_bitmap == NULL) {
274 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
277 memset(sparc_valid_addr_bitmap, 0, i << 2);
281 max_mapnr = last_valid_pfn - pfn_base;
282 high_memory = __va(max_low_pfn << PAGE_SHIFT);
285 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
286 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
287 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
289 if (end_pfn <= highstart_pfn)
292 if (start_pfn < highstart_pfn)
293 start_pfn = highstart_pfn;
295 map_high_region(start_pfn, end_pfn);
298 mem_init_print_info(NULL);
301 void free_initmem (void)
303 free_initmem_default(POISON_FREE_INITMEM);
306 #ifdef CONFIG_BLK_DEV_INITRD
307 void free_initrd_mem(unsigned long start, unsigned long end)
309 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
314 void sparc_flush_page_to_ram(struct page *page)
316 unsigned long vaddr = (unsigned long)page_address(page);
319 __flush_page_to_ram(vaddr);
321 EXPORT_SYMBOL(sparc_flush_page_to_ram);