1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * PowerPC version 4 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 5 * 6 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) 7 * and Cort Dougan (PReP) (cort@cs.nmt.edu) 8 * Copyright (C) 1996 Paul Mackerras 9 * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com) 10 * 11 * Derived from "arch/i386/mm/init.c" 12 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 13 */ 14 15 #include <linux/memblock.h> 16 #include <linux/highmem.h> 17 #include <linux/suspend.h> 18 #include <linux/dma-direct.h> 19 20 #include <asm/machdep.h> 21 #include <asm/rtas.h> 22 #include <asm/kasan.h> 23 #include <asm/svm.h> 24 #include <asm/mmzone.h> 25 26 #include <mm/mmu_decl.h> 27 28 unsigned long long memory_limit; 29 bool init_mem_is_free; 30 31 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 32 EXPORT_SYMBOL(empty_zero_page); 33 34 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 35 unsigned long size, pgprot_t vma_prot) 36 { 37 if (ppc_md.phys_mem_access_prot) 38 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 39 40 if (!page_is_ram(pfn)) 41 vma_prot = pgprot_noncached(vma_prot); 42 43 return vma_prot; 44 } 45 EXPORT_SYMBOL(phys_mem_access_prot); 46 47 #ifdef CONFIG_MEMORY_HOTPLUG 48 static DEFINE_MUTEX(linear_mapping_mutex); 49 50 #ifdef CONFIG_NUMA 51 int memory_add_physaddr_to_nid(u64 start) 52 { 53 return hot_add_scn_to_nid(start); 54 } 55 #endif 56 57 int __weak create_section_mapping(unsigned long start, unsigned long end, 58 int nid, pgprot_t prot) 59 { 60 return -ENODEV; 61 } 62 63 int __weak remove_section_mapping(unsigned long start, unsigned long end) 64 { 65 return -ENODEV; 66 } 67 68 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size, 69 struct mhp_params *params) 70 { 71 int rc; 72 73 start = (unsigned long)__va(start); 74 mutex_lock(&linear_mapping_mutex); 75 rc = create_section_mapping(start, start + size, nid, 76 params->pgprot); 77 mutex_unlock(&linear_mapping_mutex); 78 if (rc) { 79 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n", 80 start, start + size, rc); 81 return -EFAULT; 82 } 83 return 0; 84 } 85 86 void __ref arch_remove_linear_mapping(u64 start, u64 size) 87 { 88 int ret; 89 90 /* Remove htab bolted mappings for this section of memory */ 91 start = (unsigned long)__va(start); 92 93 mutex_lock(&linear_mapping_mutex); 94 ret = remove_section_mapping(start, start + size); 95 mutex_unlock(&linear_mapping_mutex); 96 if (ret) 97 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n", 98 start, start + size, ret); 99 100 /* Ensure all vmalloc mappings are flushed in case they also 101 * hit that section of memory 102 */ 103 vm_unmap_aliases(); 104 } 105 106 int __ref arch_add_memory(int nid, u64 start, u64 size, 107 struct mhp_params *params) 108 { 109 unsigned long start_pfn = start >> PAGE_SHIFT; 110 unsigned long nr_pages = size >> PAGE_SHIFT; 111 int rc; 112 113 rc = arch_create_linear_mapping(nid, start, size, params); 114 if (rc) 115 return rc; 116 rc = __add_pages(nid, start_pfn, nr_pages, params); 117 if (rc) 118 arch_remove_linear_mapping(start, size); 119 return rc; 120 } 121 122 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 123 { 124 unsigned long start_pfn = start >> PAGE_SHIFT; 125 unsigned long nr_pages = size >> PAGE_SHIFT; 126 127 __remove_pages(start_pfn, nr_pages, altmap); 128 arch_remove_linear_mapping(start, size); 129 } 130 #endif 131 132 #ifndef CONFIG_NUMA 133 void __init mem_topology_setup(void) 134 { 135 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 136 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 137 #ifdef CONFIG_HIGHMEM 138 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 139 #endif 140 141 /* Place all memblock_regions in the same node and merge contiguous 142 * memblock_regions 143 */ 144 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 145 } 146 147 void __init initmem_init(void) 148 { 149 sparse_init(); 150 } 151 152 /* mark pages that don't exist as nosave */ 153 static int __init mark_nonram_nosave(void) 154 { 155 unsigned long spfn, epfn, prev = 0; 156 int i; 157 158 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) { 159 if (prev && prev < spfn) 160 register_nosave_region(prev, spfn); 161 162 prev = epfn; 163 } 164 165 return 0; 166 } 167 #else /* CONFIG_NUMA */ 168 static int __init mark_nonram_nosave(void) 169 { 170 return 0; 171 } 172 #endif 173 174 /* 175 * Zones usage: 176 * 177 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be 178 * everything else. GFP_DMA32 page allocations automatically fall back to 179 * ZONE_DMA. 180 * 181 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the 182 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU 183 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by 184 * ZONE_DMA. 185 */ 186 static unsigned long max_zone_pfns[MAX_NR_ZONES]; 187 188 /* 189 * paging_init() sets up the page tables - in fact we've already done this. 190 */ 191 void __init paging_init(void) 192 { 193 unsigned long long total_ram = memblock_phys_mem_size(); 194 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 195 196 #ifdef CONFIG_HIGHMEM 197 unsigned long v = __fix_to_virt(FIX_KMAP_END); 198 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN); 199 200 for (; v < end; v += PAGE_SIZE) 201 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 202 203 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 204 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 205 #endif /* CONFIG_HIGHMEM */ 206 207 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 208 (unsigned long long)top_of_ram, total_ram); 209 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 210 (long int)((top_of_ram - total_ram) >> 20)); 211 212 /* 213 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 214 * powerbooks. 215 */ 216 if (IS_ENABLED(CONFIG_PPC32)) 217 zone_dma_bits = 30; 218 else 219 zone_dma_bits = 31; 220 221 #ifdef CONFIG_ZONE_DMA 222 max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 223 1UL << (zone_dma_bits - PAGE_SHIFT)); 224 #endif 225 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 226 #ifdef CONFIG_HIGHMEM 227 max_zone_pfns[ZONE_HIGHMEM] = max_pfn; 228 #endif 229 230 free_area_init(max_zone_pfns); 231 232 mark_nonram_nosave(); 233 } 234 235 void __init mem_init(void) 236 { 237 /* 238 * book3s is limited to 16 page sizes due to encoding this in 239 * a 4-bit field for slices. 240 */ 241 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 242 243 #ifdef CONFIG_SWIOTLB 244 /* 245 * Some platforms (e.g. 85xx) limit DMA-able memory way below 246 * 4G. We force memblock to bottom-up mode to ensure that the 247 * memory allocated in swiotlb_init() is DMA-able. 248 * As it's the last memblock allocation, no need to reset it 249 * back to to-down. 250 */ 251 memblock_set_bottom_up(true); 252 if (is_secure_guest()) 253 svm_swiotlb_init(); 254 else 255 swiotlb_init(0); 256 #endif 257 258 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 259 set_max_mapnr(max_low_pfn); 260 261 kasan_late_init(); 262 263 memblock_free_all(); 264 265 #ifdef CONFIG_HIGHMEM 266 { 267 unsigned long pfn, highmem_mapnr; 268 269 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 270 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 271 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; 272 struct page *page = pfn_to_page(pfn); 273 if (!memblock_is_reserved(paddr)) 274 free_highmem_page(page); 275 } 276 } 277 #endif /* CONFIG_HIGHMEM */ 278 279 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP) 280 /* 281 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 282 * functions.... do it here for the non-smp case. 283 */ 284 per_cpu(next_tlbcam_idx, smp_processor_id()) = 285 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 286 #endif 287 288 #ifdef CONFIG_PPC32 289 pr_info("Kernel virtual memory layout:\n"); 290 #ifdef CONFIG_KASAN 291 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n", 292 KASAN_SHADOW_START, KASAN_SHADOW_END); 293 #endif 294 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 295 #ifdef CONFIG_HIGHMEM 296 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 297 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 298 #endif /* CONFIG_HIGHMEM */ 299 if (ioremap_bot != IOREMAP_TOP) 300 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 301 ioremap_bot, IOREMAP_TOP); 302 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 303 VMALLOC_START, VMALLOC_END); 304 #ifdef MODULES_VADDR 305 pr_info(" * 0x%08lx..0x%08lx : modules\n", 306 MODULES_VADDR, MODULES_END); 307 #endif 308 #endif /* CONFIG_PPC32 */ 309 } 310 311 void free_initmem(void) 312 { 313 ppc_md.progress = ppc_printk_progress; 314 mark_initmem_nx(); 315 init_mem_is_free = true; 316 free_initmem_default(POISON_FREE_INITMEM); 317 } 318 319 /* 320 * System memory should not be in /proc/iomem but various tools expect it 321 * (eg kdump). 322 */ 323 static int __init add_system_ram_resources(void) 324 { 325 phys_addr_t start, end; 326 u64 i; 327 328 for_each_mem_range(i, &start, &end) { 329 struct resource *res; 330 331 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 332 WARN_ON(!res); 333 334 if (res) { 335 res->name = "System RAM"; 336 res->start = start; 337 /* 338 * In memblock, end points to the first byte after 339 * the range while in resourses, end points to the 340 * last byte in the range. 341 */ 342 res->end = end - 1; 343 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 344 WARN_ON(request_resource(&iomem_resource, res) < 0); 345 } 346 } 347 348 return 0; 349 } 350 subsys_initcall(add_system_ram_resources); 351 352 #ifdef CONFIG_STRICT_DEVMEM 353 /* 354 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 355 * is valid. The argument is a physical page number. 356 * 357 * Access has to be given to non-kernel-ram areas as well, these contain the 358 * PCI mmio resources as well as potential bios/acpi data regions. 359 */ 360 int devmem_is_allowed(unsigned long pfn) 361 { 362 if (page_is_rtas_user_buf(pfn)) 363 return 1; 364 if (iomem_is_exclusive(PFN_PHYS(pfn))) 365 return 0; 366 if (!page_is_ram(pfn)) 367 return 1; 368 return 0; 369 } 370 #endif /* CONFIG_STRICT_DEVMEM */ 371 372 /* 373 * This is defined in kernel/resource.c but only powerpc needs to export it, for 374 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed. 375 */ 376 EXPORT_SYMBOL_GPL(walk_system_ram_range); 377