1 /* 2 * S390 version 3 * Copyright IBM Corp. 1999 4 * Author(s): Hartmut Penner (hp@de.ibm.com) 5 * 6 * Derived from "arch/i386/mm/init.c" 7 * Copyright (C) 1995 Linus Torvalds 8 */ 9 10 #include <linux/signal.h> 11 #include <linux/sched.h> 12 #include <linux/kernel.h> 13 #include <linux/errno.h> 14 #include <linux/string.h> 15 #include <linux/types.h> 16 #include <linux/ptrace.h> 17 #include <linux/mman.h> 18 #include <linux/mm.h> 19 #include <linux/swap.h> 20 #include <linux/smp.h> 21 #include <linux/init.h> 22 #include <linux/pagemap.h> 23 #include <linux/bootmem.h> 24 #include <linux/memory.h> 25 #include <linux/pfn.h> 26 #include <linux/poison.h> 27 #include <linux/initrd.h> 28 #include <linux/export.h> 29 #include <linux/gfp.h> 30 #include <linux/memblock.h> 31 #include <asm/processor.h> 32 #include <asm/uaccess.h> 33 #include <asm/pgtable.h> 34 #include <asm/pgalloc.h> 35 #include <asm/dma.h> 36 #include <asm/lowcore.h> 37 #include <asm/tlb.h> 38 #include <asm/tlbflush.h> 39 #include <asm/sections.h> 40 #include <asm/ctl_reg.h> 41 #include <asm/sclp.h> 42 43 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE))); 44 45 unsigned long empty_zero_page, zero_page_mask; 46 EXPORT_SYMBOL(empty_zero_page); 47 EXPORT_SYMBOL(zero_page_mask); 48 49 static void __init setup_zero_pages(void) 50 { 51 struct cpuid cpu_id; 52 unsigned int order; 53 struct page *page; 54 int i; 55 56 get_cpu_id(&cpu_id); 57 switch (cpu_id.machine) { 58 case 0x9672: /* g5 */ 59 case 0x2064: /* z900 */ 60 case 0x2066: /* z900 */ 61 case 0x2084: /* z990 */ 62 case 0x2086: /* z990 */ 63 case 0x2094: /* z9-109 */ 64 case 0x2096: /* z9-109 */ 65 order = 0; 66 break; 67 case 0x2097: /* z10 */ 68 case 0x2098: /* z10 */ 69 case 0x2817: /* z196 */ 70 case 0x2818: /* z196 */ 71 order = 2; 72 break; 73 case 0x2827: /* zEC12 */ 74 case 0x2828: /* zEC12 */ 75 order = 5; 76 break; 77 case 0x2964: /* z13 */ 78 default: 79 order = 7; 80 break; 81 } 82 /* Limit number of empty zero pages for small memory sizes */ 83 while (order > 2 && (totalram_pages >> 10) < (1UL << order)) 84 order--; 85 86 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 87 if (!empty_zero_page) 88 panic("Out of memory in setup_zero_pages"); 89 90 page = virt_to_page((void *) empty_zero_page); 91 split_page(page, order); 92 for (i = 1 << order; i > 0; i--) { 93 mark_page_reserved(page); 94 page++; 95 } 96 97 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 98 } 99 100 /* 101 * paging_init() sets up the page tables 102 */ 103 void __init paging_init(void) 104 { 105 unsigned long max_zone_pfns[MAX_NR_ZONES]; 106 unsigned long pgd_type, asce_bits; 107 108 init_mm.pgd = swapper_pg_dir; 109 if (VMALLOC_END > (1UL << 42)) { 110 asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH; 111 pgd_type = _REGION2_ENTRY_EMPTY; 112 } else { 113 asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 114 pgd_type = _REGION3_ENTRY_EMPTY; 115 } 116 S390_lowcore.kernel_asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; 117 clear_table((unsigned long *) init_mm.pgd, pgd_type, 118 sizeof(unsigned long)*2048); 119 vmem_map_init(); 120 121 /* enable virtual mapping in kernel mode */ 122 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 123 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 124 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 125 arch_local_irq_restore(4UL << (BITS_PER_LONG - 8)); 126 127 sparse_memory_present_with_active_regions(MAX_NUMNODES); 128 sparse_init(); 129 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 130 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 131 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 132 free_area_init_nodes(max_zone_pfns); 133 } 134 135 void __init mem_init(void) 136 { 137 if (MACHINE_HAS_TLB_LC) 138 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); 139 cpumask_set_cpu(0, mm_cpumask(&init_mm)); 140 atomic_set(&init_mm.context.attach_count, 1); 141 142 set_max_mapnr(max_low_pfn); 143 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 144 145 /* Setup guest page hinting */ 146 cmma_init(); 147 148 /* this will put all low memory onto the freelists */ 149 free_all_bootmem(); 150 setup_zero_pages(); /* Setup zeroed pages. */ 151 152 mem_init_print_info(NULL); 153 printk("Write protected kernel read-only data: %#lx - %#lx\n", 154 (unsigned long)&_stext, 155 PFN_ALIGN((unsigned long)&_eshared) - 1); 156 } 157 158 void free_initmem(void) 159 { 160 free_initmem_default(POISON_FREE_INITMEM); 161 } 162 163 #ifdef CONFIG_BLK_DEV_INITRD 164 void __init free_initrd_mem(unsigned long start, unsigned long end) 165 { 166 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM, 167 "initrd"); 168 } 169 #endif 170 171 #ifdef CONFIG_MEMORY_HOTPLUG 172 int arch_add_memory(int nid, u64 start, u64 size, bool for_device) 173 { 174 unsigned long normal_end_pfn = PFN_DOWN(memblock_end_of_DRAM()); 175 unsigned long dma_end_pfn = PFN_DOWN(MAX_DMA_ADDRESS); 176 unsigned long start_pfn = PFN_DOWN(start); 177 unsigned long size_pages = PFN_DOWN(size); 178 unsigned long nr_pages; 179 int rc, zone_enum; 180 181 rc = vmem_add_mapping(start, size); 182 if (rc) 183 return rc; 184 185 while (size_pages > 0) { 186 if (start_pfn < dma_end_pfn) { 187 nr_pages = (start_pfn + size_pages > dma_end_pfn) ? 188 dma_end_pfn - start_pfn : size_pages; 189 zone_enum = ZONE_DMA; 190 } else if (start_pfn < normal_end_pfn) { 191 nr_pages = (start_pfn + size_pages > normal_end_pfn) ? 192 normal_end_pfn - start_pfn : size_pages; 193 zone_enum = ZONE_NORMAL; 194 } else { 195 nr_pages = size_pages; 196 zone_enum = ZONE_MOVABLE; 197 } 198 rc = __add_pages(nid, NODE_DATA(nid)->node_zones + zone_enum, 199 start_pfn, size_pages); 200 if (rc) 201 break; 202 start_pfn += nr_pages; 203 size_pages -= nr_pages; 204 } 205 if (rc) 206 vmem_remove_mapping(start, size); 207 return rc; 208 } 209 210 unsigned long memory_block_size_bytes(void) 211 { 212 /* 213 * Make sure the memory block size is always greater 214 * or equal than the memory increment size. 215 */ 216 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm); 217 } 218 219 #ifdef CONFIG_MEMORY_HOTREMOVE 220 int arch_remove_memory(u64 start, u64 size) 221 { 222 /* 223 * There is no hardware or firmware interface which could trigger a 224 * hot memory remove on s390. So there is nothing that needs to be 225 * implemented. 226 */ 227 return -EBUSY; 228 } 229 #endif 230 #endif /* CONFIG_MEMORY_HOTPLUG */ 231