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 struct dev_pagemap *pgmap) 163 { 164 unsigned long start_pfn = start >> PAGE_SHIFT; 165 unsigned long nr_pages = size >> PAGE_SHIFT; 166 167 __remove_pages(start_pfn, nr_pages, altmap, pgmap); 168 arch_remove_linear_mapping(start, size); 169 } 170 #endif 171 172 #ifndef CONFIG_NUMA 173 void __init mem_topology_setup(void) 174 { 175 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 176 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 177 #ifdef CONFIG_HIGHMEM 178 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 179 #endif 180 181 /* Place all memblock_regions in the same node and merge contiguous 182 * memblock_regions 183 */ 184 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 185 } 186 187 /* mark pages that don't exist as nosave */ 188 static int __init mark_nonram_nosave(void) 189 { 190 unsigned long spfn, epfn, prev = 0; 191 int i; 192 193 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) { 194 if (prev && prev < spfn) 195 register_nosave_region(prev, spfn); 196 197 prev = epfn; 198 } 199 200 return 0; 201 } 202 #else /* CONFIG_NUMA */ 203 static int __init mark_nonram_nosave(void) 204 { 205 return 0; 206 } 207 #endif 208 209 /* 210 * Zones usage: 211 * 212 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be 213 * everything else. GFP_DMA32 page allocations automatically fall back to 214 * ZONE_DMA. 215 * 216 * By using 31-bit unconditionally, we can exploit zone_dma_limit to inform the 217 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU 218 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by 219 * ZONE_DMA. 220 */ 221 void __init arch_zone_limits_init(unsigned long *max_zone_pfns) 222 { 223 #ifdef CONFIG_ZONE_DMA 224 max_zone_pfns[ZONE_DMA] = min((zone_dma_limit >> PAGE_SHIFT) + 1, max_low_pfn); 225 #endif 226 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 227 #ifdef CONFIG_HIGHMEM 228 max_zone_pfns[ZONE_HIGHMEM] = max_pfn; 229 #endif 230 } 231 232 /* 233 * paging_init() sets up the page tables - in fact we've already done this. 234 */ 235 void __init paging_init(void) 236 { 237 unsigned long long total_ram = memblock_phys_mem_size(); 238 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 239 int zone_dma_bits; 240 241 #ifdef CONFIG_HIGHMEM 242 unsigned long v = __fix_to_virt(FIX_KMAP_END); 243 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN); 244 245 for (; v < end; v += PAGE_SIZE) 246 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 247 248 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 249 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 250 #endif /* CONFIG_HIGHMEM */ 251 252 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 253 (unsigned long long)top_of_ram, total_ram); 254 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 255 (long int)((top_of_ram - total_ram) >> 20)); 256 257 /* 258 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 259 * powerbooks. 260 */ 261 if (IS_ENABLED(CONFIG_PPC32)) 262 zone_dma_bits = 30; 263 else 264 zone_dma_bits = 31; 265 266 zone_dma_limit = DMA_BIT_MASK(zone_dma_bits); 267 268 mark_nonram_nosave(); 269 } 270 271 void __init arch_mm_preinit(void) 272 { 273 274 /* 275 * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM 276 * and hugetlb. These must be called after pageblock_order is 277 * initialised. 278 */ 279 fadump_cma_init(); 280 kdump_cma_reserve(); 281 kvm_cma_reserve(); 282 283 /* 284 * book3s is limited to 16 page sizes due to encoding this in 285 * a 4-bit field for slices. 286 */ 287 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 288 289 #ifdef CONFIG_SWIOTLB 290 /* 291 * Some platforms (e.g. 85xx) limit DMA-able memory way below 292 * 4G. We force memblock to bottom-up mode to ensure that the 293 * memory allocated in swiotlb_init() is DMA-able. 294 * As it's the last memblock allocation, no need to reset it 295 * back to to-down. 296 */ 297 memblock_set_bottom_up(true); 298 swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags); 299 #endif 300 301 kasan_late_init(); 302 303 #if defined(CONFIG_PPC_E500) && !defined(CONFIG_SMP) 304 /* 305 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 306 * functions.... do it here for the non-smp case. 307 */ 308 per_cpu(next_tlbcam_idx, smp_processor_id()) = 309 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 310 #endif 311 } 312 313 void free_initmem(void) 314 { 315 ppc_md.progress = ppc_printk_progress; 316 mark_initmem_nx(); 317 free_initmem_default(POISON_FREE_INITMEM); 318 ftrace_free_init_tramp(); 319 } 320 321 /* 322 * System memory should not be in /proc/iomem but various tools expect it 323 * (eg kdump). 324 */ 325 static int __init add_system_ram_resources(void) 326 { 327 phys_addr_t start, end; 328 u64 i; 329 330 for_each_mem_range(i, &start, &end) { 331 struct resource *res; 332 333 res = kzalloc_obj(struct resource); 334 WARN_ON(!res); 335 336 if (res) { 337 res->name = "System RAM"; 338 res->start = start; 339 /* 340 * In memblock, end points to the first byte after 341 * the range while in resourses, end points to the 342 * last byte in the range. 343 */ 344 res->end = end - 1; 345 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 346 WARN_ON(insert_resource(&iomem_resource, res) < 0); 347 } 348 } 349 350 return 0; 351 } 352 subsys_initcall(add_system_ram_resources); 353 354 #ifdef CONFIG_STRICT_DEVMEM 355 /* 356 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 357 * is valid. The argument is a physical page number. 358 * 359 * Access has to be given to non-kernel-ram areas as well, these contain the 360 * PCI mmio resources as well as potential bios/acpi data regions. 361 */ 362 int devmem_is_allowed(unsigned long pfn) 363 { 364 if (page_is_rtas_user_buf(pfn)) 365 return 1; 366 if (iomem_is_exclusive(PFN_PHYS(pfn))) 367 return 0; 368 if (!page_is_ram(pfn)) 369 return 1; 370 return 0; 371 } 372 #endif /* CONFIG_STRICT_DEVMEM */ 373 374 /* 375 * This is defined in kernel/resource.c but only powerpc needs to export it, for 376 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed. 377 */ 378 EXPORT_SYMBOL_GPL(walk_system_ram_range); 379 380 #ifdef CONFIG_EXECMEM 381 static struct execmem_info execmem_info __ro_after_init; 382 383 #if defined(CONFIG_PPC_8xx) || defined(CONFIG_PPC_BOOK3S_603) 384 static void prealloc_execmem_pgtable(void) 385 { 386 unsigned long va; 387 388 for (va = ALIGN_DOWN(MODULES_VADDR, PGDIR_SIZE); va < MODULES_END; va += PGDIR_SIZE) 389 pte_alloc_kernel(pmd_off_k(va), va); 390 } 391 #else 392 static void prealloc_execmem_pgtable(void) { } 393 #endif 394 395 struct execmem_info __init *execmem_arch_setup(void) 396 { 397 pgprot_t kprobes_prot = strict_module_rwx_enabled() ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC; 398 pgprot_t prot = strict_module_rwx_enabled() ? PAGE_KERNEL : PAGE_KERNEL_EXEC; 399 unsigned long fallback_start = 0, fallback_end = 0; 400 unsigned long start, end; 401 402 /* 403 * BOOK3S_32 and 8xx define MODULES_VADDR for text allocations and 404 * allow allocating data in the entire vmalloc space 405 */ 406 #ifdef MODULES_VADDR 407 unsigned long limit = (unsigned long)_etext - SZ_32M; 408 409 /* First try within 32M limit from _etext to avoid branch trampolines */ 410 if (MODULES_VADDR < PAGE_OFFSET && MODULES_END > limit) { 411 start = limit; 412 fallback_start = MODULES_VADDR; 413 fallback_end = MODULES_END; 414 } else { 415 start = MODULES_VADDR; 416 } 417 418 end = MODULES_END; 419 #else 420 start = VMALLOC_START; 421 end = VMALLOC_END; 422 #endif 423 424 prealloc_execmem_pgtable(); 425 426 execmem_info = (struct execmem_info){ 427 .ranges = { 428 [EXECMEM_DEFAULT] = { 429 .start = start, 430 .end = end, 431 .pgprot = prot, 432 .alignment = 1, 433 .fallback_start = fallback_start, 434 .fallback_end = fallback_end, 435 }, 436 [EXECMEM_KPROBES] = { 437 .start = VMALLOC_START, 438 .end = VMALLOC_END, 439 .pgprot = kprobes_prot, 440 .alignment = 1, 441 }, 442 [EXECMEM_MODULE_DATA] = { 443 .start = VMALLOC_START, 444 .end = VMALLOC_END, 445 .pgprot = PAGE_KERNEL, 446 .alignment = 1, 447 }, 448 }, 449 }; 450 451 return &execmem_info; 452 } 453 #endif /* CONFIG_EXECMEM */ 454