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/export.h> 16 #include <linux/sched.h> 17 #include <linux/kernel.h> 18 #include <linux/errno.h> 19 #include <linux/string.h> 20 #include <linux/gfp.h> 21 #include <linux/types.h> 22 #include <linux/mm.h> 23 #include <linux/stddef.h> 24 #include <linux/init.h> 25 #include <linux/memblock.h> 26 #include <linux/highmem.h> 27 #include <linux/initrd.h> 28 #include <linux/pagemap.h> 29 #include <linux/suspend.h> 30 #include <linux/hugetlb.h> 31 #include <linux/slab.h> 32 #include <linux/vmalloc.h> 33 #include <linux/memremap.h> 34 #include <linux/dma-direct.h> 35 36 #include <asm/pgalloc.h> 37 #include <asm/prom.h> 38 #include <asm/io.h> 39 #include <asm/mmu_context.h> 40 #include <asm/pgtable.h> 41 #include <asm/mmu.h> 42 #include <asm/smp.h> 43 #include <asm/machdep.h> 44 #include <asm/btext.h> 45 #include <asm/tlb.h> 46 #include <asm/sections.h> 47 #include <asm/sparsemem.h> 48 #include <asm/vdso.h> 49 #include <asm/fixmap.h> 50 #include <asm/swiotlb.h> 51 #include <asm/rtas.h> 52 53 #include <mm/mmu_decl.h> 54 55 #ifndef CPU_FTR_COHERENT_ICACHE 56 #define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */ 57 #define CPU_FTR_NOEXECUTE 0 58 #endif 59 60 unsigned long long memory_limit; 61 bool init_mem_is_free; 62 63 #ifdef CONFIG_HIGHMEM 64 pte_t *kmap_pte; 65 EXPORT_SYMBOL(kmap_pte); 66 pgprot_t kmap_prot; 67 EXPORT_SYMBOL(kmap_prot); 68 69 static inline pte_t *virt_to_kpte(unsigned long vaddr) 70 { 71 return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), 72 vaddr), vaddr), vaddr); 73 } 74 #endif 75 76 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 77 unsigned long size, pgprot_t vma_prot) 78 { 79 if (ppc_md.phys_mem_access_prot) 80 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 81 82 if (!page_is_ram(pfn)) 83 vma_prot = pgprot_noncached(vma_prot); 84 85 return vma_prot; 86 } 87 EXPORT_SYMBOL(phys_mem_access_prot); 88 89 #ifdef CONFIG_MEMORY_HOTPLUG 90 91 #ifdef CONFIG_NUMA 92 int memory_add_physaddr_to_nid(u64 start) 93 { 94 return hot_add_scn_to_nid(start); 95 } 96 #endif 97 98 int __weak create_section_mapping(unsigned long start, unsigned long end, int nid) 99 { 100 return -ENODEV; 101 } 102 103 int __weak remove_section_mapping(unsigned long start, unsigned long end) 104 { 105 return -ENODEV; 106 } 107 108 int __ref arch_add_memory(int nid, u64 start, u64 size, 109 struct mhp_restrictions *restrictions) 110 { 111 unsigned long start_pfn = start >> PAGE_SHIFT; 112 unsigned long nr_pages = size >> PAGE_SHIFT; 113 int rc; 114 115 resize_hpt_for_hotplug(memblock_phys_mem_size()); 116 117 start = (unsigned long)__va(start); 118 rc = create_section_mapping(start, start + size, nid); 119 if (rc) { 120 pr_warn("Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n", 121 start, start + size, rc); 122 return -EFAULT; 123 } 124 flush_dcache_range(start, start + size); 125 126 return __add_pages(nid, start_pfn, nr_pages, restrictions); 127 } 128 129 void __ref arch_remove_memory(int nid, u64 start, u64 size, 130 struct vmem_altmap *altmap) 131 { 132 unsigned long start_pfn = start >> PAGE_SHIFT; 133 unsigned long nr_pages = size >> PAGE_SHIFT; 134 struct page *page = pfn_to_page(start_pfn) + vmem_altmap_offset(altmap); 135 int ret; 136 137 __remove_pages(page_zone(page), start_pfn, nr_pages, altmap); 138 139 /* Remove htab bolted mappings for this section of memory */ 140 start = (unsigned long)__va(start); 141 flush_dcache_range(start, start + size); 142 ret = remove_section_mapping(start, start + size); 143 WARN_ON_ONCE(ret); 144 145 /* Ensure all vmalloc mappings are flushed in case they also 146 * hit that section of memory 147 */ 148 vm_unmap_aliases(); 149 150 if (resize_hpt_for_hotplug(memblock_phys_mem_size()) == -ENOSPC) 151 pr_warn("Hash collision while resizing HPT\n"); 152 } 153 #endif 154 155 #ifndef CONFIG_NEED_MULTIPLE_NODES 156 void __init mem_topology_setup(void) 157 { 158 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 159 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 160 #ifdef CONFIG_HIGHMEM 161 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 162 #endif 163 164 /* Place all memblock_regions in the same node and merge contiguous 165 * memblock_regions 166 */ 167 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 168 } 169 170 void __init initmem_init(void) 171 { 172 /* XXX need to clip this if using highmem? */ 173 sparse_memory_present_with_active_regions(0); 174 sparse_init(); 175 } 176 177 /* mark pages that don't exist as nosave */ 178 static int __init mark_nonram_nosave(void) 179 { 180 struct memblock_region *reg, *prev = NULL; 181 182 for_each_memblock(memory, reg) { 183 if (prev && 184 memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg)) 185 register_nosave_region(memblock_region_memory_end_pfn(prev), 186 memblock_region_memory_base_pfn(reg)); 187 prev = reg; 188 } 189 return 0; 190 } 191 #else /* CONFIG_NEED_MULTIPLE_NODES */ 192 static int __init mark_nonram_nosave(void) 193 { 194 return 0; 195 } 196 #endif 197 198 /* 199 * Zones usage: 200 * 201 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be 202 * everything else. GFP_DMA32 page allocations automatically fall back to 203 * ZONE_DMA. 204 * 205 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the 206 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU 207 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by 208 * ZONE_DMA. 209 */ 210 static unsigned long max_zone_pfns[MAX_NR_ZONES]; 211 212 /* 213 * paging_init() sets up the page tables - in fact we've already done this. 214 */ 215 void __init paging_init(void) 216 { 217 unsigned long long total_ram = memblock_phys_mem_size(); 218 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 219 220 #ifdef CONFIG_PPC32 221 unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1); 222 unsigned long end = __fix_to_virt(FIX_HOLE); 223 224 for (; v < end; v += PAGE_SIZE) 225 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 226 #endif 227 228 #ifdef CONFIG_HIGHMEM 229 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 230 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 231 232 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN)); 233 kmap_prot = PAGE_KERNEL; 234 #endif /* CONFIG_HIGHMEM */ 235 236 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 237 (unsigned long long)top_of_ram, total_ram); 238 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 239 (long int)((top_of_ram - total_ram) >> 20)); 240 241 /* 242 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 243 * powerbooks. 244 */ 245 if (IS_ENABLED(CONFIG_PPC32)) 246 zone_dma_bits = 30; 247 else 248 zone_dma_bits = 31; 249 250 #ifdef CONFIG_ZONE_DMA 251 max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 252 1UL << (zone_dma_bits - PAGE_SHIFT)); 253 #endif 254 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 255 #ifdef CONFIG_HIGHMEM 256 max_zone_pfns[ZONE_HIGHMEM] = max_pfn; 257 #endif 258 259 free_area_init_nodes(max_zone_pfns); 260 261 mark_nonram_nosave(); 262 } 263 264 void __init mem_init(void) 265 { 266 /* 267 * book3s is limited to 16 page sizes due to encoding this in 268 * a 4-bit field for slices. 269 */ 270 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 271 272 #ifdef CONFIG_SWIOTLB 273 swiotlb_init(0); 274 #endif 275 276 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 277 set_max_mapnr(max_pfn); 278 memblock_free_all(); 279 280 #ifdef CONFIG_HIGHMEM 281 { 282 unsigned long pfn, highmem_mapnr; 283 284 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 285 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 286 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; 287 struct page *page = pfn_to_page(pfn); 288 if (!memblock_is_reserved(paddr)) 289 free_highmem_page(page); 290 } 291 } 292 #endif /* CONFIG_HIGHMEM */ 293 294 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP) 295 /* 296 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 297 * functions.... do it here for the non-smp case. 298 */ 299 per_cpu(next_tlbcam_idx, smp_processor_id()) = 300 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 301 #endif 302 303 mem_init_print_info(NULL); 304 #ifdef CONFIG_PPC32 305 pr_info("Kernel virtual memory layout:\n"); 306 #ifdef CONFIG_KASAN 307 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n", 308 KASAN_SHADOW_START, KASAN_SHADOW_END); 309 #endif 310 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 311 #ifdef CONFIG_HIGHMEM 312 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 313 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 314 #endif /* CONFIG_HIGHMEM */ 315 if (ioremap_bot != IOREMAP_TOP) 316 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 317 ioremap_bot, IOREMAP_TOP); 318 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 319 VMALLOC_START, VMALLOC_END); 320 #endif /* CONFIG_PPC32 */ 321 } 322 323 void free_initmem(void) 324 { 325 ppc_md.progress = ppc_printk_progress; 326 mark_initmem_nx(); 327 init_mem_is_free = true; 328 free_initmem_default(POISON_FREE_INITMEM); 329 } 330 331 /* 332 * This is called when a page has been modified by the kernel. 333 * It just marks the page as not i-cache clean. We do the i-cache 334 * flush later when the page is given to a user process, if necessary. 335 */ 336 void flush_dcache_page(struct page *page) 337 { 338 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) 339 return; 340 /* avoid an atomic op if possible */ 341 if (test_bit(PG_arch_1, &page->flags)) 342 clear_bit(PG_arch_1, &page->flags); 343 } 344 EXPORT_SYMBOL(flush_dcache_page); 345 346 void flush_dcache_icache_page(struct page *page) 347 { 348 #ifdef CONFIG_HUGETLB_PAGE 349 if (PageCompound(page)) { 350 flush_dcache_icache_hugepage(page); 351 return; 352 } 353 #endif 354 #if defined(CONFIG_PPC_8xx) || defined(CONFIG_PPC64) 355 /* On 8xx there is no need to kmap since highmem is not supported */ 356 __flush_dcache_icache(page_address(page)); 357 #else 358 if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) { 359 void *start = kmap_atomic(page); 360 __flush_dcache_icache(start); 361 kunmap_atomic(start); 362 } else { 363 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT); 364 } 365 #endif 366 } 367 EXPORT_SYMBOL(flush_dcache_icache_page); 368 369 void clear_user_page(void *page, unsigned long vaddr, struct page *pg) 370 { 371 clear_page(page); 372 373 /* 374 * We shouldn't have to do this, but some versions of glibc 375 * require it (ld.so assumes zero filled pages are icache clean) 376 * - Anton 377 */ 378 flush_dcache_page(pg); 379 } 380 EXPORT_SYMBOL(clear_user_page); 381 382 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, 383 struct page *pg) 384 { 385 copy_page(vto, vfrom); 386 387 /* 388 * We should be able to use the following optimisation, however 389 * there are two problems. 390 * Firstly a bug in some versions of binutils meant PLT sections 391 * were not marked executable. 392 * Secondly the first word in the GOT section is blrl, used 393 * to establish the GOT address. Until recently the GOT was 394 * not marked executable. 395 * - Anton 396 */ 397 #if 0 398 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0)) 399 return; 400 #endif 401 402 flush_dcache_page(pg); 403 } 404 405 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page, 406 unsigned long addr, int len) 407 { 408 unsigned long maddr; 409 410 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK); 411 flush_icache_range(maddr, maddr + len); 412 kunmap(page); 413 } 414 EXPORT_SYMBOL(flush_icache_user_range); 415 416 /* 417 * System memory should not be in /proc/iomem but various tools expect it 418 * (eg kdump). 419 */ 420 static int __init add_system_ram_resources(void) 421 { 422 struct memblock_region *reg; 423 424 for_each_memblock(memory, reg) { 425 struct resource *res; 426 unsigned long base = reg->base; 427 unsigned long size = reg->size; 428 429 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 430 WARN_ON(!res); 431 432 if (res) { 433 res->name = "System RAM"; 434 res->start = base; 435 res->end = base + size - 1; 436 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 437 WARN_ON(request_resource(&iomem_resource, res) < 0); 438 } 439 } 440 441 return 0; 442 } 443 subsys_initcall(add_system_ram_resources); 444 445 #ifdef CONFIG_STRICT_DEVMEM 446 /* 447 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 448 * is valid. The argument is a physical page number. 449 * 450 * Access has to be given to non-kernel-ram areas as well, these contain the 451 * PCI mmio resources as well as potential bios/acpi data regions. 452 */ 453 int devmem_is_allowed(unsigned long pfn) 454 { 455 if (page_is_rtas_user_buf(pfn)) 456 return 1; 457 if (iomem_is_exclusive(PFN_PHYS(pfn))) 458 return 0; 459 if (!page_is_ram(pfn)) 460 return 1; 461 return 0; 462 } 463 #endif /* CONFIG_STRICT_DEVMEM */ 464 465 /* 466 * This is defined in kernel/resource.c but only powerpc needs to export it, for 467 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed. 468 */ 469 EXPORT_SYMBOL_GPL(walk_system_ram_range); 470