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 #include <linux/execmem.h> 20 #include <linux/vmalloc.h> 21 22 #include <asm/swiotlb.h> 23 #include <asm/machdep.h> 24 #include <asm/rtas.h> 25 #include <asm/kasan.h> 26 #include <asm/svm.h> 27 #include <asm/mmzone.h> 28 #include <asm/ftrace.h> 29 #include <asm/code-patching.h> 30 #include <asm/setup.h> 31 #include <asm/fixmap.h> 32 33 #include <mm/mmu_decl.h> 34 35 unsigned long long memory_limit __initdata; 36 37 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 38 EXPORT_SYMBOL(empty_zero_page); 39 40 pgprot_t __phys_mem_access_prot(unsigned long pfn, unsigned long size, 41 pgprot_t vma_prot) 42 { 43 if (ppc_md.phys_mem_access_prot) 44 return ppc_md.phys_mem_access_prot(pfn, size, vma_prot); 45 46 if (!page_is_ram(pfn)) 47 vma_prot = pgprot_noncached(vma_prot); 48 49 return vma_prot; 50 } 51 EXPORT_SYMBOL(__phys_mem_access_prot); 52 53 #ifdef CONFIG_MEMORY_HOTPLUG 54 static DEFINE_MUTEX(linear_mapping_mutex); 55 56 #ifdef CONFIG_NUMA 57 int memory_add_physaddr_to_nid(u64 start) 58 { 59 return hot_add_scn_to_nid(start); 60 } 61 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); 62 #endif 63 64 int __weak create_section_mapping(unsigned long start, unsigned long end, 65 int nid, pgprot_t prot) 66 { 67 return -ENODEV; 68 } 69 70 int __weak remove_section_mapping(unsigned long start, unsigned long end) 71 { 72 return -ENODEV; 73 } 74 75 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size, 76 struct mhp_params *params) 77 { 78 int rc; 79 80 start = (unsigned long)__va(start); 81 mutex_lock(&linear_mapping_mutex); 82 rc = create_section_mapping(start, start + size, nid, 83 params->pgprot); 84 mutex_unlock(&linear_mapping_mutex); 85 if (rc) { 86 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n", 87 start, start + size, rc); 88 return -EFAULT; 89 } 90 return 0; 91 } 92 93 void __ref arch_remove_linear_mapping(u64 start, u64 size) 94 { 95 int ret; 96 97 /* Remove htab bolted mappings for this section of memory */ 98 start = (unsigned long)__va(start); 99 100 mutex_lock(&linear_mapping_mutex); 101 ret = remove_section_mapping(start, start + size); 102 mutex_unlock(&linear_mapping_mutex); 103 if (ret) 104 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n", 105 start, start + size, ret); 106 107 /* Ensure all vmalloc mappings are flushed in case they also 108 * hit that section of memory 109 */ 110 vm_unmap_aliases(); 111 } 112 113 /* 114 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need 115 * updating. 116 */ 117 static void update_end_of_memory_vars(u64 start, u64 size) 118 { 119 unsigned long end_pfn = PFN_UP(start + size); 120 121 if (end_pfn > max_pfn) { 122 max_pfn = end_pfn; 123 max_low_pfn = end_pfn; 124 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; 125 } 126 } 127 128 int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, 129 struct mhp_params *params) 130 { 131 int ret; 132 133 ret = __add_pages(nid, start_pfn, nr_pages, params); 134 if (ret) 135 return ret; 136 137 /* update max_pfn, max_low_pfn and high_memory */ 138 update_end_of_memory_vars(start_pfn << PAGE_SHIFT, 139 nr_pages << PAGE_SHIFT); 140 141 return ret; 142 } 143 144 int __ref arch_add_memory(int nid, u64 start, u64 size, 145 struct mhp_params *params) 146 { 147 unsigned long start_pfn = start >> PAGE_SHIFT; 148 unsigned long nr_pages = size >> PAGE_SHIFT; 149 int rc; 150 151 rc = arch_create_linear_mapping(nid, start, size, params); 152 if (rc) 153 return rc; 154 rc = add_pages(nid, start_pfn, nr_pages, params); 155 if (rc) 156 arch_remove_linear_mapping(start, size); 157 return rc; 158 } 159 160 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 161 { 162 unsigned long start_pfn = start >> PAGE_SHIFT; 163 unsigned long nr_pages = size >> PAGE_SHIFT; 164 165 __remove_pages(start_pfn, nr_pages, altmap); 166 arch_remove_linear_mapping(start, size); 167 } 168 #endif 169 170 #ifndef CONFIG_NUMA 171 void __init mem_topology_setup(void) 172 { 173 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 174 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 175 #ifdef CONFIG_HIGHMEM 176 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 177 #endif 178 179 /* Place all memblock_regions in the same node and merge contiguous 180 * memblock_regions 181 */ 182 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 183 } 184 185 void __init initmem_init(void) 186 { 187 sparse_init(); 188 } 189 190 /* mark pages that don't exist as nosave */ 191 static int __init mark_nonram_nosave(void) 192 { 193 unsigned long spfn, epfn, prev = 0; 194 int i; 195 196 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) { 197 if (prev && prev < spfn) 198 register_nosave_region(prev, spfn); 199 200 prev = epfn; 201 } 202 203 return 0; 204 } 205 #else /* CONFIG_NUMA */ 206 static int __init mark_nonram_nosave(void) 207 { 208 return 0; 209 } 210 #endif 211 212 /* 213 * Zones usage: 214 * 215 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be 216 * everything else. GFP_DMA32 page allocations automatically fall back to 217 * ZONE_DMA. 218 * 219 * By using 31-bit unconditionally, we can exploit zone_dma_limit to inform the 220 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU 221 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by 222 * ZONE_DMA. 223 */ 224 static unsigned long max_zone_pfns[MAX_NR_ZONES]; 225 226 /* 227 * paging_init() sets up the page tables - in fact we've already done this. 228 */ 229 void __init paging_init(void) 230 { 231 unsigned long long total_ram = memblock_phys_mem_size(); 232 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 233 int zone_dma_bits; 234 235 #ifdef CONFIG_HIGHMEM 236 unsigned long v = __fix_to_virt(FIX_KMAP_END); 237 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN); 238 239 for (; v < end; v += PAGE_SIZE) 240 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 241 242 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 243 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 244 #endif /* CONFIG_HIGHMEM */ 245 246 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 247 (unsigned long long)top_of_ram, total_ram); 248 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 249 (long int)((top_of_ram - total_ram) >> 20)); 250 251 /* 252 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 253 * powerbooks. 254 */ 255 if (IS_ENABLED(CONFIG_PPC32)) 256 zone_dma_bits = 30; 257 else 258 zone_dma_bits = 31; 259 260 zone_dma_limit = DMA_BIT_MASK(zone_dma_bits); 261 262 #ifdef CONFIG_ZONE_DMA 263 max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 264 1UL << (zone_dma_bits - PAGE_SHIFT)); 265 #endif 266 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 267 #ifdef CONFIG_HIGHMEM 268 max_zone_pfns[ZONE_HIGHMEM] = max_pfn; 269 #endif 270 271 free_area_init(max_zone_pfns); 272 273 mark_nonram_nosave(); 274 } 275 276 void __init mem_init(void) 277 { 278 /* 279 * book3s is limited to 16 page sizes due to encoding this in 280 * a 4-bit field for slices. 281 */ 282 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 283 284 #ifdef CONFIG_SWIOTLB 285 /* 286 * Some platforms (e.g. 85xx) limit DMA-able memory way below 287 * 4G. We force memblock to bottom-up mode to ensure that the 288 * memory allocated in swiotlb_init() is DMA-able. 289 * As it's the last memblock allocation, no need to reset it 290 * back to to-down. 291 */ 292 memblock_set_bottom_up(true); 293 swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags); 294 #endif 295 296 kasan_late_init(); 297 298 memblock_free_all(); 299 300 #ifdef CONFIG_HIGHMEM 301 { 302 unsigned long pfn, highmem_mapnr; 303 304 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 305 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 306 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; 307 struct page *page = pfn_to_page(pfn); 308 if (memblock_is_memory(paddr) && !memblock_is_reserved(paddr)) 309 free_highmem_page(page); 310 } 311 } 312 #endif /* CONFIG_HIGHMEM */ 313 314 #if defined(CONFIG_PPC_E500) && !defined(CONFIG_SMP) 315 /* 316 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 317 * functions.... do it here for the non-smp case. 318 */ 319 per_cpu(next_tlbcam_idx, smp_processor_id()) = 320 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 321 #endif 322 323 #ifdef CONFIG_PPC32 324 pr_info("Kernel virtual memory layout:\n"); 325 #ifdef CONFIG_KASAN 326 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n", 327 KASAN_SHADOW_START, KASAN_SHADOW_END); 328 #endif 329 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 330 #ifdef CONFIG_HIGHMEM 331 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 332 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 333 #endif /* CONFIG_HIGHMEM */ 334 if (ioremap_bot != IOREMAP_TOP) 335 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 336 ioremap_bot, IOREMAP_TOP); 337 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 338 VMALLOC_START, VMALLOC_END); 339 #ifdef MODULES_VADDR 340 pr_info(" * 0x%08lx..0x%08lx : modules\n", 341 MODULES_VADDR, MODULES_END); 342 #endif 343 #endif /* CONFIG_PPC32 */ 344 } 345 346 void free_initmem(void) 347 { 348 ppc_md.progress = ppc_printk_progress; 349 mark_initmem_nx(); 350 free_initmem_default(POISON_FREE_INITMEM); 351 ftrace_free_init_tramp(); 352 } 353 354 /* 355 * System memory should not be in /proc/iomem but various tools expect it 356 * (eg kdump). 357 */ 358 static int __init add_system_ram_resources(void) 359 { 360 phys_addr_t start, end; 361 u64 i; 362 363 for_each_mem_range(i, &start, &end) { 364 struct resource *res; 365 366 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 367 WARN_ON(!res); 368 369 if (res) { 370 res->name = "System RAM"; 371 res->start = start; 372 /* 373 * In memblock, end points to the first byte after 374 * the range while in resourses, end points to the 375 * last byte in the range. 376 */ 377 res->end = end - 1; 378 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 379 WARN_ON(request_resource(&iomem_resource, res) < 0); 380 } 381 } 382 383 return 0; 384 } 385 subsys_initcall(add_system_ram_resources); 386 387 #ifdef CONFIG_STRICT_DEVMEM 388 /* 389 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 390 * is valid. The argument is a physical page number. 391 * 392 * Access has to be given to non-kernel-ram areas as well, these contain the 393 * PCI mmio resources as well as potential bios/acpi data regions. 394 */ 395 int devmem_is_allowed(unsigned long pfn) 396 { 397 if (page_is_rtas_user_buf(pfn)) 398 return 1; 399 if (iomem_is_exclusive(PFN_PHYS(pfn))) 400 return 0; 401 if (!page_is_ram(pfn)) 402 return 1; 403 return 0; 404 } 405 #endif /* CONFIG_STRICT_DEVMEM */ 406 407 /* 408 * This is defined in kernel/resource.c but only powerpc needs to export it, for 409 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed. 410 */ 411 EXPORT_SYMBOL_GPL(walk_system_ram_range); 412 413 #ifdef CONFIG_EXECMEM 414 static struct execmem_info execmem_info __ro_after_init; 415 416 #if defined(CONFIG_PPC_8xx) || defined(CONFIG_PPC_BOOK3S_603) 417 static void prealloc_execmem_pgtable(void) 418 { 419 unsigned long va; 420 421 for (va = ALIGN_DOWN(MODULES_VADDR, PGDIR_SIZE); va < MODULES_END; va += PGDIR_SIZE) 422 pte_alloc_kernel(pmd_off_k(va), va); 423 } 424 #else 425 static void prealloc_execmem_pgtable(void) { } 426 #endif 427 428 struct execmem_info __init *execmem_arch_setup(void) 429 { 430 pgprot_t kprobes_prot = strict_module_rwx_enabled() ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC; 431 pgprot_t prot = strict_module_rwx_enabled() ? PAGE_KERNEL : PAGE_KERNEL_EXEC; 432 unsigned long fallback_start = 0, fallback_end = 0; 433 unsigned long start, end; 434 435 /* 436 * BOOK3S_32 and 8xx define MODULES_VADDR for text allocations and 437 * allow allocating data in the entire vmalloc space 438 */ 439 #ifdef MODULES_VADDR 440 unsigned long limit = (unsigned long)_etext - SZ_32M; 441 442 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR); 443 444 /* First try within 32M limit from _etext to avoid branch trampolines */ 445 if (MODULES_VADDR < PAGE_OFFSET && MODULES_END > limit) { 446 start = limit; 447 fallback_start = MODULES_VADDR; 448 fallback_end = MODULES_END; 449 } else { 450 start = MODULES_VADDR; 451 } 452 453 end = MODULES_END; 454 #else 455 start = VMALLOC_START; 456 end = VMALLOC_END; 457 #endif 458 459 prealloc_execmem_pgtable(); 460 461 execmem_info = (struct execmem_info){ 462 .ranges = { 463 [EXECMEM_DEFAULT] = { 464 .start = start, 465 .end = end, 466 .pgprot = prot, 467 .alignment = 1, 468 .fallback_start = fallback_start, 469 .fallback_end = fallback_end, 470 }, 471 [EXECMEM_KPROBES] = { 472 .start = VMALLOC_START, 473 .end = VMALLOC_END, 474 .pgprot = kprobes_prot, 475 .alignment = 1, 476 }, 477 [EXECMEM_MODULE_DATA] = { 478 .start = VMALLOC_START, 479 .end = VMALLOC_END, 480 .pgprot = PAGE_KERNEL, 481 .alignment = 1, 482 }, 483 }, 484 }; 485 486 return &execmem_info; 487 } 488 #endif /* CONFIG_EXECMEM */ 489