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/text-patching.h> 30 #include <asm/setup.h> 31 #include <asm/fixmap.h> 32 33 #include <asm/fadump.h> 34 #include <asm/kexec.h> 35 #include <asm/kvm_ppc.h> 36 37 #include <mm/mmu_decl.h> 38 39 unsigned long long memory_limit __initdata; 40 41 pgprot_t __phys_mem_access_prot(unsigned long pfn, unsigned long size, 42 pgprot_t vma_prot) 43 { 44 if (ppc_md.phys_mem_access_prot) 45 return ppc_md.phys_mem_access_prot(pfn, size, vma_prot); 46 47 if (!page_is_ram(pfn)) 48 vma_prot = pgprot_noncached(vma_prot); 49 50 return vma_prot; 51 } 52 EXPORT_SYMBOL(__phys_mem_access_prot); 53 54 #ifdef CONFIG_MEMORY_HOTPLUG 55 static DEFINE_MUTEX(linear_mapping_mutex); 56 57 #ifdef CONFIG_NUMA 58 int memory_add_physaddr_to_nid(u64 start) 59 { 60 return hot_add_scn_to_nid(start); 61 } 62 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); 63 #endif 64 65 int __weak create_section_mapping(unsigned long start, unsigned long end, 66 int nid, pgprot_t prot) 67 { 68 return -ENODEV; 69 } 70 71 int __weak remove_section_mapping(unsigned long start, unsigned long end) 72 { 73 return -ENODEV; 74 } 75 76 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size, 77 struct mhp_params *params) 78 { 79 int rc; 80 81 start = (unsigned long)__va(start); 82 mutex_lock(&linear_mapping_mutex); 83 rc = create_section_mapping(start, start + size, nid, 84 params->pgprot); 85 mutex_unlock(&linear_mapping_mutex); 86 if (rc) { 87 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n", 88 start, start + size, rc); 89 return -EFAULT; 90 } 91 return 0; 92 } 93 94 void __ref arch_remove_linear_mapping(u64 start, u64 size) 95 { 96 int ret; 97 98 /* Remove htab bolted mappings for this section of memory */ 99 start = (unsigned long)__va(start); 100 101 mutex_lock(&linear_mapping_mutex); 102 ret = remove_section_mapping(start, start + size); 103 mutex_unlock(&linear_mapping_mutex); 104 if (ret) 105 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n", 106 start, start + size, ret); 107 108 /* Ensure all vmalloc mappings are flushed in case they also 109 * hit that section of memory 110 */ 111 vm_unmap_aliases(); 112 } 113 114 /* 115 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need 116 * updating. 117 */ 118 static void update_end_of_memory_vars(u64 start, u64 size) 119 { 120 unsigned long end_pfn = PFN_UP(start + size); 121 122 if (end_pfn > max_pfn) { 123 max_pfn = end_pfn; 124 max_low_pfn = end_pfn; 125 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; 126 } 127 } 128 129 int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, 130 struct mhp_params *params) 131 { 132 int ret; 133 134 ret = __add_pages(nid, start_pfn, nr_pages, params); 135 if (ret) 136 return ret; 137 138 /* update max_pfn, max_low_pfn and high_memory */ 139 update_end_of_memory_vars(start_pfn << PAGE_SHIFT, 140 nr_pages << PAGE_SHIFT); 141 142 return ret; 143 } 144 145 int __ref arch_add_memory(int nid, u64 start, u64 size, 146 struct mhp_params *params) 147 { 148 unsigned long start_pfn = start >> PAGE_SHIFT; 149 unsigned long nr_pages = size >> PAGE_SHIFT; 150 int rc; 151 152 rc = arch_create_linear_mapping(nid, start, size, params); 153 if (rc) 154 return rc; 155 rc = add_pages(nid, start_pfn, nr_pages, params); 156 if (rc) 157 arch_remove_linear_mapping(start, size); 158 return rc; 159 } 160 161 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 162 { 163 unsigned long start_pfn = start >> PAGE_SHIFT; 164 unsigned long nr_pages = size >> PAGE_SHIFT; 165 166 __remove_pages(start_pfn, nr_pages, altmap); 167 arch_remove_linear_mapping(start, size); 168 } 169 #endif 170 171 #ifndef CONFIG_NUMA 172 void __init mem_topology_setup(void) 173 { 174 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 175 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 176 #ifdef CONFIG_HIGHMEM 177 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 178 #endif 179 180 /* Place all memblock_regions in the same node and merge contiguous 181 * memblock_regions 182 */ 183 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 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_limit 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 void __init arch_zone_limits_init(unsigned long *max_zone_pfns) 221 { 222 #ifdef CONFIG_ZONE_DMA 223 max_zone_pfns[ZONE_DMA] = min((zone_dma_limit >> PAGE_SHIFT) + 1, max_low_pfn); 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 } 230 231 /* 232 * paging_init() sets up the page tables - in fact we've already done this. 233 */ 234 void __init paging_init(void) 235 { 236 unsigned long long total_ram = memblock_phys_mem_size(); 237 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 238 int zone_dma_bits; 239 240 #ifdef CONFIG_HIGHMEM 241 unsigned long v = __fix_to_virt(FIX_KMAP_END); 242 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN); 243 244 for (; v < end; v += PAGE_SIZE) 245 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 246 247 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 248 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 249 #endif /* CONFIG_HIGHMEM */ 250 251 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 252 (unsigned long long)top_of_ram, total_ram); 253 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 254 (long int)((top_of_ram - total_ram) >> 20)); 255 256 /* 257 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 258 * powerbooks. 259 */ 260 if (IS_ENABLED(CONFIG_PPC32)) 261 zone_dma_bits = 30; 262 else 263 zone_dma_bits = 31; 264 265 zone_dma_limit = DMA_BIT_MASK(zone_dma_bits); 266 267 mark_nonram_nosave(); 268 } 269 270 void __init arch_mm_preinit(void) 271 { 272 273 /* 274 * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM 275 * and hugetlb. These must be called after pageblock_order is 276 * initialised. 277 */ 278 fadump_cma_init(); 279 kdump_cma_reserve(); 280 kvm_cma_reserve(); 281 282 /* 283 * book3s is limited to 16 page sizes due to encoding this in 284 * a 4-bit field for slices. 285 */ 286 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 287 288 #ifdef CONFIG_SWIOTLB 289 /* 290 * Some platforms (e.g. 85xx) limit DMA-able memory way below 291 * 4G. We force memblock to bottom-up mode to ensure that the 292 * memory allocated in swiotlb_init() is DMA-able. 293 * As it's the last memblock allocation, no need to reset it 294 * back to to-down. 295 */ 296 memblock_set_bottom_up(true); 297 swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags); 298 #endif 299 300 kasan_late_init(); 301 302 #if defined(CONFIG_PPC_E500) && !defined(CONFIG_SMP) 303 /* 304 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 305 * functions.... do it here for the non-smp case. 306 */ 307 per_cpu(next_tlbcam_idx, smp_processor_id()) = 308 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 309 #endif 310 } 311 312 void free_initmem(void) 313 { 314 ppc_md.progress = ppc_printk_progress; 315 mark_initmem_nx(); 316 free_initmem_default(POISON_FREE_INITMEM); 317 ftrace_free_init_tramp(); 318 } 319 320 /* 321 * System memory should not be in /proc/iomem but various tools expect it 322 * (eg kdump). 323 */ 324 static int __init add_system_ram_resources(void) 325 { 326 phys_addr_t start, end; 327 u64 i; 328 329 for_each_mem_range(i, &start, &end) { 330 struct resource *res; 331 332 res = kzalloc_obj(struct resource); 333 WARN_ON(!res); 334 335 if (res) { 336 res->name = "System RAM"; 337 res->start = start; 338 /* 339 * In memblock, end points to the first byte after 340 * the range while in resourses, end points to the 341 * last byte in the range. 342 */ 343 res->end = end - 1; 344 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 345 WARN_ON(insert_resource(&iomem_resource, res) < 0); 346 } 347 } 348 349 return 0; 350 } 351 subsys_initcall(add_system_ram_resources); 352 353 #ifdef CONFIG_STRICT_DEVMEM 354 /* 355 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 356 * is valid. The argument is a physical page number. 357 * 358 * Access has to be given to non-kernel-ram areas as well, these contain the 359 * PCI mmio resources as well as potential bios/acpi data regions. 360 */ 361 int devmem_is_allowed(unsigned long pfn) 362 { 363 if (page_is_rtas_user_buf(pfn)) 364 return 1; 365 if (iomem_is_exclusive(PFN_PHYS(pfn))) 366 return 0; 367 if (!page_is_ram(pfn)) 368 return 1; 369 return 0; 370 } 371 #endif /* CONFIG_STRICT_DEVMEM */ 372 373 /* 374 * This is defined in kernel/resource.c but only powerpc needs to export it, for 375 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed. 376 */ 377 EXPORT_SYMBOL_GPL(walk_system_ram_range); 378 379 #ifdef CONFIG_EXECMEM 380 static struct execmem_info execmem_info __ro_after_init; 381 382 #if defined(CONFIG_PPC_8xx) || defined(CONFIG_PPC_BOOK3S_603) 383 static void prealloc_execmem_pgtable(void) 384 { 385 unsigned long va; 386 387 for (va = ALIGN_DOWN(MODULES_VADDR, PGDIR_SIZE); va < MODULES_END; va += PGDIR_SIZE) 388 pte_alloc_kernel(pmd_off_k(va), va); 389 } 390 #else 391 static void prealloc_execmem_pgtable(void) { } 392 #endif 393 394 struct execmem_info __init *execmem_arch_setup(void) 395 { 396 pgprot_t kprobes_prot = strict_module_rwx_enabled() ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC; 397 pgprot_t prot = strict_module_rwx_enabled() ? PAGE_KERNEL : PAGE_KERNEL_EXEC; 398 unsigned long fallback_start = 0, fallback_end = 0; 399 unsigned long start, end; 400 401 /* 402 * BOOK3S_32 and 8xx define MODULES_VADDR for text allocations and 403 * allow allocating data in the entire vmalloc space 404 */ 405 #ifdef MODULES_VADDR 406 unsigned long limit = (unsigned long)_etext - SZ_32M; 407 408 /* First try within 32M limit from _etext to avoid branch trampolines */ 409 if (MODULES_VADDR < PAGE_OFFSET && MODULES_END > limit) { 410 start = limit; 411 fallback_start = MODULES_VADDR; 412 fallback_end = MODULES_END; 413 } else { 414 start = MODULES_VADDR; 415 } 416 417 end = MODULES_END; 418 #else 419 start = VMALLOC_START; 420 end = VMALLOC_END; 421 #endif 422 423 prealloc_execmem_pgtable(); 424 425 execmem_info = (struct execmem_info){ 426 .ranges = { 427 [EXECMEM_DEFAULT] = { 428 .start = start, 429 .end = end, 430 .pgprot = prot, 431 .alignment = 1, 432 .fallback_start = fallback_start, 433 .fallback_end = fallback_end, 434 }, 435 [EXECMEM_KPROBES] = { 436 .start = VMALLOC_START, 437 .end = VMALLOC_END, 438 .pgprot = kprobes_prot, 439 .alignment = 1, 440 }, 441 [EXECMEM_MODULE_DATA] = { 442 .start = VMALLOC_START, 443 .end = VMALLOC_END, 444 .pgprot = PAGE_KERNEL, 445 .alignment = 1, 446 }, 447 }, 448 }; 449 450 return &execmem_info; 451 } 452 #endif /* CONFIG_EXECMEM */ 453