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/swiotlb.h> 21 #include <asm/machdep.h> 22 #include <asm/rtas.h> 23 #include <asm/kasan.h> 24 #include <asm/svm.h> 25 #include <asm/mmzone.h> 26 #include <asm/ftrace.h> 27 #include <asm/code-patching.h> 28 #include <asm/setup.h> 29 30 #include <mm/mmu_decl.h> 31 32 unsigned long long memory_limit; 33 34 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 35 EXPORT_SYMBOL(empty_zero_page); 36 37 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 38 unsigned long size, pgprot_t vma_prot) 39 { 40 if (ppc_md.phys_mem_access_prot) 41 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 42 43 if (!page_is_ram(pfn)) 44 vma_prot = pgprot_noncached(vma_prot); 45 46 return vma_prot; 47 } 48 EXPORT_SYMBOL(phys_mem_access_prot); 49 50 #ifdef CONFIG_MEMORY_HOTPLUG 51 static DEFINE_MUTEX(linear_mapping_mutex); 52 53 #ifdef CONFIG_NUMA 54 int memory_add_physaddr_to_nid(u64 start) 55 { 56 return hot_add_scn_to_nid(start); 57 } 58 #endif 59 60 int __weak create_section_mapping(unsigned long start, unsigned long end, 61 int nid, pgprot_t prot) 62 { 63 return -ENODEV; 64 } 65 66 int __weak remove_section_mapping(unsigned long start, unsigned long end) 67 { 68 return -ENODEV; 69 } 70 71 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size, 72 struct mhp_params *params) 73 { 74 int rc; 75 76 start = (unsigned long)__va(start); 77 mutex_lock(&linear_mapping_mutex); 78 rc = create_section_mapping(start, start + size, nid, 79 params->pgprot); 80 mutex_unlock(&linear_mapping_mutex); 81 if (rc) { 82 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n", 83 start, start + size, rc); 84 return -EFAULT; 85 } 86 return 0; 87 } 88 89 void __ref arch_remove_linear_mapping(u64 start, u64 size) 90 { 91 int ret; 92 93 /* Remove htab bolted mappings for this section of memory */ 94 start = (unsigned long)__va(start); 95 96 mutex_lock(&linear_mapping_mutex); 97 ret = remove_section_mapping(start, start + size); 98 mutex_unlock(&linear_mapping_mutex); 99 if (ret) 100 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n", 101 start, start + size, ret); 102 103 /* Ensure all vmalloc mappings are flushed in case they also 104 * hit that section of memory 105 */ 106 vm_unmap_aliases(); 107 } 108 109 /* 110 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need 111 * updating. 112 */ 113 static void update_end_of_memory_vars(u64 start, u64 size) 114 { 115 unsigned long end_pfn = PFN_UP(start + size); 116 117 if (end_pfn > max_pfn) { 118 max_pfn = end_pfn; 119 max_low_pfn = end_pfn; 120 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; 121 } 122 } 123 124 int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, 125 struct mhp_params *params) 126 { 127 int ret; 128 129 ret = __add_pages(nid, start_pfn, nr_pages, params); 130 if (ret) 131 return ret; 132 133 /* update max_pfn, max_low_pfn and high_memory */ 134 update_end_of_memory_vars(start_pfn << PAGE_SHIFT, 135 nr_pages << PAGE_SHIFT); 136 137 return ret; 138 } 139 140 int __ref arch_add_memory(int nid, u64 start, u64 size, 141 struct mhp_params *params) 142 { 143 unsigned long start_pfn = start >> PAGE_SHIFT; 144 unsigned long nr_pages = size >> PAGE_SHIFT; 145 int rc; 146 147 rc = arch_create_linear_mapping(nid, start, size, params); 148 if (rc) 149 return rc; 150 rc = add_pages(nid, start_pfn, nr_pages, params); 151 if (rc) 152 arch_remove_linear_mapping(start, size); 153 return rc; 154 } 155 156 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 157 { 158 unsigned long start_pfn = start >> PAGE_SHIFT; 159 unsigned long nr_pages = size >> PAGE_SHIFT; 160 161 __remove_pages(start_pfn, nr_pages, altmap); 162 arch_remove_linear_mapping(start, size); 163 } 164 #endif 165 166 #ifndef CONFIG_NUMA 167 void __init mem_topology_setup(void) 168 { 169 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 170 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 171 #ifdef CONFIG_HIGHMEM 172 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 173 #endif 174 175 /* Place all memblock_regions in the same node and merge contiguous 176 * memblock_regions 177 */ 178 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 179 } 180 181 void __init initmem_init(void) 182 { 183 sparse_init(); 184 } 185 186 /* mark pages that don't exist as nosave */ 187 static int __init mark_nonram_nosave(void) 188 { 189 unsigned long spfn, epfn, prev = 0; 190 int i; 191 192 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) { 193 if (prev && prev < spfn) 194 register_nosave_region(prev, spfn); 195 196 prev = epfn; 197 } 198 199 return 0; 200 } 201 #else /* CONFIG_NUMA */ 202 static int __init mark_nonram_nosave(void) 203 { 204 return 0; 205 } 206 #endif 207 208 /* 209 * Zones usage: 210 * 211 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be 212 * everything else. GFP_DMA32 page allocations automatically fall back to 213 * ZONE_DMA. 214 * 215 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the 216 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU 217 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by 218 * ZONE_DMA. 219 */ 220 static unsigned long max_zone_pfns[MAX_NR_ZONES]; 221 222 /* 223 * paging_init() sets up the page tables - in fact we've already done this. 224 */ 225 void __init paging_init(void) 226 { 227 unsigned long long total_ram = memblock_phys_mem_size(); 228 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 229 230 #ifdef CONFIG_HIGHMEM 231 unsigned long v = __fix_to_virt(FIX_KMAP_END); 232 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN); 233 234 for (; v < end; v += PAGE_SIZE) 235 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 236 237 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 238 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 239 #endif /* CONFIG_HIGHMEM */ 240 241 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 242 (unsigned long long)top_of_ram, total_ram); 243 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 244 (long int)((top_of_ram - total_ram) >> 20)); 245 246 /* 247 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 248 * powerbooks. 249 */ 250 if (IS_ENABLED(CONFIG_PPC32)) 251 zone_dma_bits = 30; 252 else 253 zone_dma_bits = 31; 254 255 #ifdef CONFIG_ZONE_DMA 256 max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 257 1UL << (zone_dma_bits - PAGE_SHIFT)); 258 #endif 259 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 260 #ifdef CONFIG_HIGHMEM 261 max_zone_pfns[ZONE_HIGHMEM] = max_pfn; 262 #endif 263 264 free_area_init(max_zone_pfns); 265 266 mark_nonram_nosave(); 267 } 268 269 void __init mem_init(void) 270 { 271 /* 272 * book3s is limited to 16 page sizes due to encoding this in 273 * a 4-bit field for slices. 274 */ 275 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 276 277 #ifdef CONFIG_SWIOTLB 278 /* 279 * Some platforms (e.g. 85xx) limit DMA-able memory way below 280 * 4G. We force memblock to bottom-up mode to ensure that the 281 * memory allocated in swiotlb_init() is DMA-able. 282 * As it's the last memblock allocation, no need to reset it 283 * back to to-down. 284 */ 285 memblock_set_bottom_up(true); 286 swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags); 287 #endif 288 289 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 290 set_max_mapnr(max_pfn); 291 292 kasan_late_init(); 293 294 memblock_free_all(); 295 296 #ifdef CONFIG_HIGHMEM 297 { 298 unsigned long pfn, highmem_mapnr; 299 300 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 301 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 302 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; 303 struct page *page = pfn_to_page(pfn); 304 if (!memblock_is_reserved(paddr)) 305 free_highmem_page(page); 306 } 307 } 308 #endif /* CONFIG_HIGHMEM */ 309 310 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP) 311 /* 312 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 313 * functions.... do it here for the non-smp case. 314 */ 315 per_cpu(next_tlbcam_idx, smp_processor_id()) = 316 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 317 #endif 318 319 #ifdef CONFIG_PPC32 320 pr_info("Kernel virtual memory layout:\n"); 321 #ifdef CONFIG_KASAN 322 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n", 323 KASAN_SHADOW_START, KASAN_SHADOW_END); 324 #endif 325 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 326 #ifdef CONFIG_HIGHMEM 327 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 328 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 329 #endif /* CONFIG_HIGHMEM */ 330 if (ioremap_bot != IOREMAP_TOP) 331 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 332 ioremap_bot, IOREMAP_TOP); 333 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 334 VMALLOC_START, VMALLOC_END); 335 #ifdef MODULES_VADDR 336 pr_info(" * 0x%08lx..0x%08lx : modules\n", 337 MODULES_VADDR, MODULES_END); 338 #endif 339 #endif /* CONFIG_PPC32 */ 340 } 341 342 void free_initmem(void) 343 { 344 ppc_md.progress = ppc_printk_progress; 345 mark_initmem_nx(); 346 static_branch_enable(&init_mem_is_free); 347 free_initmem_default(POISON_FREE_INITMEM); 348 ftrace_free_init_tramp(); 349 } 350 351 /* 352 * System memory should not be in /proc/iomem but various tools expect it 353 * (eg kdump). 354 */ 355 static int __init add_system_ram_resources(void) 356 { 357 phys_addr_t start, end; 358 u64 i; 359 360 for_each_mem_range(i, &start, &end) { 361 struct resource *res; 362 363 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 364 WARN_ON(!res); 365 366 if (res) { 367 res->name = "System RAM"; 368 res->start = start; 369 /* 370 * In memblock, end points to the first byte after 371 * the range while in resourses, end points to the 372 * last byte in the range. 373 */ 374 res->end = end - 1; 375 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 376 WARN_ON(request_resource(&iomem_resource, res) < 0); 377 } 378 } 379 380 return 0; 381 } 382 subsys_initcall(add_system_ram_resources); 383 384 #ifdef CONFIG_STRICT_DEVMEM 385 /* 386 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 387 * is valid. The argument is a physical page number. 388 * 389 * Access has to be given to non-kernel-ram areas as well, these contain the 390 * PCI mmio resources as well as potential bios/acpi data regions. 391 */ 392 int devmem_is_allowed(unsigned long pfn) 393 { 394 if (page_is_rtas_user_buf(pfn)) 395 return 1; 396 if (iomem_is_exclusive(PFN_PHYS(pfn))) 397 return 0; 398 if (!page_is_ram(pfn)) 399 return 1; 400 return 0; 401 } 402 #endif /* CONFIG_STRICT_DEVMEM */ 403 404 /* 405 * This is defined in kernel/resource.c but only powerpc needs to export it, for 406 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed. 407 */ 408 EXPORT_SYMBOL_GPL(walk_system_ram_range); 409