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 #include <asm/fixmap.h> 30 31 #include <mm/mmu_decl.h> 32 33 unsigned long long memory_limit; 34 35 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 36 EXPORT_SYMBOL(empty_zero_page); 37 38 pgprot_t __phys_mem_access_prot(unsigned long pfn, unsigned long size, 39 pgprot_t vma_prot) 40 { 41 if (ppc_md.phys_mem_access_prot) 42 return ppc_md.phys_mem_access_prot(pfn, size, vma_prot); 43 44 if (!page_is_ram(pfn)) 45 vma_prot = pgprot_noncached(vma_prot); 46 47 return vma_prot; 48 } 49 EXPORT_SYMBOL(__phys_mem_access_prot); 50 51 #ifdef CONFIG_MEMORY_HOTPLUG 52 static DEFINE_MUTEX(linear_mapping_mutex); 53 54 #ifdef CONFIG_NUMA 55 int memory_add_physaddr_to_nid(u64 start) 56 { 57 return hot_add_scn_to_nid(start); 58 } 59 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); 60 #endif 61 62 int __weak create_section_mapping(unsigned long start, unsigned long end, 63 int nid, pgprot_t prot) 64 { 65 return -ENODEV; 66 } 67 68 int __weak remove_section_mapping(unsigned long start, unsigned long end) 69 { 70 return -ENODEV; 71 } 72 73 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size, 74 struct mhp_params *params) 75 { 76 int rc; 77 78 start = (unsigned long)__va(start); 79 mutex_lock(&linear_mapping_mutex); 80 rc = create_section_mapping(start, start + size, nid, 81 params->pgprot); 82 mutex_unlock(&linear_mapping_mutex); 83 if (rc) { 84 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n", 85 start, start + size, rc); 86 return -EFAULT; 87 } 88 return 0; 89 } 90 91 void __ref arch_remove_linear_mapping(u64 start, u64 size) 92 { 93 int ret; 94 95 /* Remove htab bolted mappings for this section of memory */ 96 start = (unsigned long)__va(start); 97 98 mutex_lock(&linear_mapping_mutex); 99 ret = remove_section_mapping(start, start + size); 100 mutex_unlock(&linear_mapping_mutex); 101 if (ret) 102 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n", 103 start, start + size, ret); 104 105 /* Ensure all vmalloc mappings are flushed in case they also 106 * hit that section of memory 107 */ 108 vm_unmap_aliases(); 109 } 110 111 /* 112 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need 113 * updating. 114 */ 115 static void update_end_of_memory_vars(u64 start, u64 size) 116 { 117 unsigned long end_pfn = PFN_UP(start + size); 118 119 if (end_pfn > max_pfn) { 120 max_pfn = end_pfn; 121 max_low_pfn = end_pfn; 122 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; 123 } 124 } 125 126 int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, 127 struct mhp_params *params) 128 { 129 int ret; 130 131 ret = __add_pages(nid, start_pfn, nr_pages, params); 132 if (ret) 133 return ret; 134 135 /* update max_pfn, max_low_pfn and high_memory */ 136 update_end_of_memory_vars(start_pfn << PAGE_SHIFT, 137 nr_pages << PAGE_SHIFT); 138 139 return ret; 140 } 141 142 int __ref arch_add_memory(int nid, u64 start, u64 size, 143 struct mhp_params *params) 144 { 145 unsigned long start_pfn = start >> PAGE_SHIFT; 146 unsigned long nr_pages = size >> PAGE_SHIFT; 147 int rc; 148 149 rc = arch_create_linear_mapping(nid, start, size, params); 150 if (rc) 151 return rc; 152 rc = add_pages(nid, start_pfn, nr_pages, params); 153 if (rc) 154 arch_remove_linear_mapping(start, size); 155 return rc; 156 } 157 158 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 159 { 160 unsigned long start_pfn = start >> PAGE_SHIFT; 161 unsigned long nr_pages = size >> PAGE_SHIFT; 162 163 __remove_pages(start_pfn, nr_pages, altmap); 164 arch_remove_linear_mapping(start, size); 165 } 166 #endif 167 168 #ifndef CONFIG_NUMA 169 void __init mem_topology_setup(void) 170 { 171 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 172 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 173 #ifdef CONFIG_HIGHMEM 174 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 175 #endif 176 177 /* Place all memblock_regions in the same node and merge contiguous 178 * memblock_regions 179 */ 180 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 181 } 182 183 void __init initmem_init(void) 184 { 185 sparse_init(); 186 } 187 188 /* mark pages that don't exist as nosave */ 189 static int __init mark_nonram_nosave(void) 190 { 191 unsigned long spfn, epfn, prev = 0; 192 int i; 193 194 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) { 195 if (prev && prev < spfn) 196 register_nosave_region(prev, spfn); 197 198 prev = epfn; 199 } 200 201 return 0; 202 } 203 #else /* CONFIG_NUMA */ 204 static int __init mark_nonram_nosave(void) 205 { 206 return 0; 207 } 208 #endif 209 210 /* 211 * Zones usage: 212 * 213 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be 214 * everything else. GFP_DMA32 page allocations automatically fall back to 215 * ZONE_DMA. 216 * 217 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the 218 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU 219 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by 220 * ZONE_DMA. 221 */ 222 static unsigned long max_zone_pfns[MAX_NR_ZONES]; 223 224 /* 225 * paging_init() sets up the page tables - in fact we've already done this. 226 */ 227 void __init paging_init(void) 228 { 229 unsigned long long total_ram = memblock_phys_mem_size(); 230 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 231 232 #ifdef CONFIG_HIGHMEM 233 unsigned long v = __fix_to_virt(FIX_KMAP_END); 234 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN); 235 236 for (; v < end; v += PAGE_SIZE) 237 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 238 239 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 240 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 241 #endif /* CONFIG_HIGHMEM */ 242 243 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 244 (unsigned long long)top_of_ram, total_ram); 245 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 246 (long int)((top_of_ram - total_ram) >> 20)); 247 248 /* 249 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 250 * powerbooks. 251 */ 252 if (IS_ENABLED(CONFIG_PPC32)) 253 zone_dma_bits = 30; 254 else 255 zone_dma_bits = 31; 256 257 #ifdef CONFIG_ZONE_DMA 258 max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 259 1UL << (zone_dma_bits - PAGE_SHIFT)); 260 #endif 261 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 262 #ifdef CONFIG_HIGHMEM 263 max_zone_pfns[ZONE_HIGHMEM] = max_pfn; 264 #endif 265 266 free_area_init(max_zone_pfns); 267 268 mark_nonram_nosave(); 269 } 270 271 void __init mem_init(void) 272 { 273 /* 274 * book3s is limited to 16 page sizes due to encoding this in 275 * a 4-bit field for slices. 276 */ 277 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 278 279 #ifdef CONFIG_SWIOTLB 280 /* 281 * Some platforms (e.g. 85xx) limit DMA-able memory way below 282 * 4G. We force memblock to bottom-up mode to ensure that the 283 * memory allocated in swiotlb_init() is DMA-able. 284 * As it's the last memblock allocation, no need to reset it 285 * back to to-down. 286 */ 287 memblock_set_bottom_up(true); 288 swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags); 289 #endif 290 291 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 292 293 kasan_late_init(); 294 295 memblock_free_all(); 296 297 #ifdef CONFIG_HIGHMEM 298 { 299 unsigned long pfn, highmem_mapnr; 300 301 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 302 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 303 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; 304 struct page *page = pfn_to_page(pfn); 305 if (memblock_is_memory(paddr) && !memblock_is_reserved(paddr)) 306 free_highmem_page(page); 307 } 308 } 309 #endif /* CONFIG_HIGHMEM */ 310 311 #if defined(CONFIG_PPC_E500) && !defined(CONFIG_SMP) 312 /* 313 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 314 * functions.... do it here for the non-smp case. 315 */ 316 per_cpu(next_tlbcam_idx, smp_processor_id()) = 317 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 318 #endif 319 320 #ifdef CONFIG_PPC32 321 pr_info("Kernel virtual memory layout:\n"); 322 #ifdef CONFIG_KASAN 323 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n", 324 KASAN_SHADOW_START, KASAN_SHADOW_END); 325 #endif 326 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 327 #ifdef CONFIG_HIGHMEM 328 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 329 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 330 #endif /* CONFIG_HIGHMEM */ 331 if (ioremap_bot != IOREMAP_TOP) 332 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 333 ioremap_bot, IOREMAP_TOP); 334 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 335 VMALLOC_START, VMALLOC_END); 336 #ifdef MODULES_VADDR 337 pr_info(" * 0x%08lx..0x%08lx : modules\n", 338 MODULES_VADDR, MODULES_END); 339 #endif 340 #endif /* CONFIG_PPC32 */ 341 } 342 343 void free_initmem(void) 344 { 345 ppc_md.progress = ppc_printk_progress; 346 mark_initmem_nx(); 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