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 29 #include <mm/mmu_decl.h> 30 31 unsigned long long memory_limit; 32 33 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 34 EXPORT_SYMBOL(empty_zero_page); 35 36 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 37 unsigned long size, pgprot_t vma_prot) 38 { 39 if (ppc_md.phys_mem_access_prot) 40 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 41 42 if (!page_is_ram(pfn)) 43 vma_prot = pgprot_noncached(vma_prot); 44 45 return vma_prot; 46 } 47 EXPORT_SYMBOL(phys_mem_access_prot); 48 49 #ifdef CONFIG_MEMORY_HOTPLUG 50 static DEFINE_MUTEX(linear_mapping_mutex); 51 52 #ifdef CONFIG_NUMA 53 int memory_add_physaddr_to_nid(u64 start) 54 { 55 return hot_add_scn_to_nid(start); 56 } 57 #endif 58 59 int __weak create_section_mapping(unsigned long start, unsigned long end, 60 int nid, pgprot_t prot) 61 { 62 return -ENODEV; 63 } 64 65 int __weak remove_section_mapping(unsigned long start, unsigned long end) 66 { 67 return -ENODEV; 68 } 69 70 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size, 71 struct mhp_params *params) 72 { 73 int rc; 74 75 start = (unsigned long)__va(start); 76 mutex_lock(&linear_mapping_mutex); 77 rc = create_section_mapping(start, start + size, nid, 78 params->pgprot); 79 mutex_unlock(&linear_mapping_mutex); 80 if (rc) { 81 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n", 82 start, start + size, rc); 83 return -EFAULT; 84 } 85 return 0; 86 } 87 88 void __ref arch_remove_linear_mapping(u64 start, u64 size) 89 { 90 int ret; 91 92 /* Remove htab bolted mappings for this section of memory */ 93 start = (unsigned long)__va(start); 94 95 mutex_lock(&linear_mapping_mutex); 96 ret = remove_section_mapping(start, start + size); 97 mutex_unlock(&linear_mapping_mutex); 98 if (ret) 99 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n", 100 start, start + size, ret); 101 102 /* Ensure all vmalloc mappings are flushed in case they also 103 * hit that section of memory 104 */ 105 vm_unmap_aliases(); 106 } 107 108 /* 109 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need 110 * updating. 111 */ 112 static void update_end_of_memory_vars(u64 start, u64 size) 113 { 114 unsigned long end_pfn = PFN_UP(start + size); 115 116 if (end_pfn > max_pfn) { 117 max_pfn = end_pfn; 118 max_low_pfn = end_pfn; 119 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; 120 } 121 } 122 123 int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, 124 struct mhp_params *params) 125 { 126 int ret; 127 128 ret = __add_pages(nid, start_pfn, nr_pages, params); 129 if (ret) 130 return ret; 131 132 /* update max_pfn, max_low_pfn and high_memory */ 133 update_end_of_memory_vars(start_pfn << PAGE_SHIFT, 134 nr_pages << PAGE_SHIFT); 135 136 return ret; 137 } 138 139 int __ref arch_add_memory(int nid, u64 start, u64 size, 140 struct mhp_params *params) 141 { 142 unsigned long start_pfn = start >> PAGE_SHIFT; 143 unsigned long nr_pages = size >> PAGE_SHIFT; 144 int rc; 145 146 rc = arch_create_linear_mapping(nid, start, size, params); 147 if (rc) 148 return rc; 149 rc = add_pages(nid, start_pfn, nr_pages, params); 150 if (rc) 151 arch_remove_linear_mapping(start, size); 152 return rc; 153 } 154 155 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 156 { 157 unsigned long start_pfn = start >> PAGE_SHIFT; 158 unsigned long nr_pages = size >> PAGE_SHIFT; 159 160 __remove_pages(start_pfn, nr_pages, altmap); 161 arch_remove_linear_mapping(start, size); 162 } 163 #endif 164 165 #ifndef CONFIG_NUMA 166 void __init mem_topology_setup(void) 167 { 168 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 169 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 170 #ifdef CONFIG_HIGHMEM 171 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 172 #endif 173 174 /* Place all memblock_regions in the same node and merge contiguous 175 * memblock_regions 176 */ 177 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 178 } 179 180 void __init initmem_init(void) 181 { 182 sparse_init(); 183 } 184 185 /* mark pages that don't exist as nosave */ 186 static int __init mark_nonram_nosave(void) 187 { 188 unsigned long spfn, epfn, prev = 0; 189 int i; 190 191 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) { 192 if (prev && prev < spfn) 193 register_nosave_region(prev, spfn); 194 195 prev = epfn; 196 } 197 198 return 0; 199 } 200 #else /* CONFIG_NUMA */ 201 static int __init mark_nonram_nosave(void) 202 { 203 return 0; 204 } 205 #endif 206 207 /* 208 * Zones usage: 209 * 210 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be 211 * everything else. GFP_DMA32 page allocations automatically fall back to 212 * ZONE_DMA. 213 * 214 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the 215 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU 216 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by 217 * ZONE_DMA. 218 */ 219 static unsigned long max_zone_pfns[MAX_NR_ZONES]; 220 221 /* 222 * paging_init() sets up the page tables - in fact we've already done this. 223 */ 224 void __init paging_init(void) 225 { 226 unsigned long long total_ram = memblock_phys_mem_size(); 227 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 228 229 #ifdef CONFIG_HIGHMEM 230 unsigned long v = __fix_to_virt(FIX_KMAP_END); 231 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN); 232 233 for (; v < end; v += PAGE_SIZE) 234 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 235 236 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 237 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 238 #endif /* CONFIG_HIGHMEM */ 239 240 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 241 (unsigned long long)top_of_ram, total_ram); 242 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 243 (long int)((top_of_ram - total_ram) >> 20)); 244 245 /* 246 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 247 * powerbooks. 248 */ 249 if (IS_ENABLED(CONFIG_PPC32)) 250 zone_dma_bits = 30; 251 else 252 zone_dma_bits = 31; 253 254 #ifdef CONFIG_ZONE_DMA 255 max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 256 1UL << (zone_dma_bits - PAGE_SHIFT)); 257 #endif 258 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 259 #ifdef CONFIG_HIGHMEM 260 max_zone_pfns[ZONE_HIGHMEM] = max_pfn; 261 #endif 262 263 free_area_init(max_zone_pfns); 264 265 mark_nonram_nosave(); 266 } 267 268 void __init mem_init(void) 269 { 270 /* 271 * book3s is limited to 16 page sizes due to encoding this in 272 * a 4-bit field for slices. 273 */ 274 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 275 276 #ifdef CONFIG_SWIOTLB 277 /* 278 * Some platforms (e.g. 85xx) limit DMA-able memory way below 279 * 4G. We force memblock to bottom-up mode to ensure that the 280 * memory allocated in swiotlb_init() is DMA-able. 281 * As it's the last memblock allocation, no need to reset it 282 * back to to-down. 283 */ 284 memblock_set_bottom_up(true); 285 swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags); 286 #endif 287 288 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 289 set_max_mapnr(max_pfn); 290 291 kasan_late_init(); 292 293 memblock_free_all(); 294 295 #ifdef CONFIG_HIGHMEM 296 { 297 unsigned long pfn, highmem_mapnr; 298 299 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 300 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 301 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; 302 struct page *page = pfn_to_page(pfn); 303 if (!memblock_is_reserved(paddr)) 304 free_highmem_page(page); 305 } 306 } 307 #endif /* CONFIG_HIGHMEM */ 308 309 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP) 310 /* 311 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 312 * functions.... do it here for the non-smp case. 313 */ 314 per_cpu(next_tlbcam_idx, smp_processor_id()) = 315 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 316 #endif 317 318 #ifdef CONFIG_PPC32 319 pr_info("Kernel virtual memory layout:\n"); 320 #ifdef CONFIG_KASAN 321 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n", 322 KASAN_SHADOW_START, KASAN_SHADOW_END); 323 #endif 324 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 325 #ifdef CONFIG_HIGHMEM 326 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 327 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 328 #endif /* CONFIG_HIGHMEM */ 329 if (ioremap_bot != IOREMAP_TOP) 330 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 331 ioremap_bot, IOREMAP_TOP); 332 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 333 VMALLOC_START, VMALLOC_END); 334 #ifdef MODULES_VADDR 335 pr_info(" * 0x%08lx..0x%08lx : modules\n", 336 MODULES_VADDR, MODULES_END); 337 #endif 338 #endif /* CONFIG_PPC32 */ 339 } 340 341 void free_initmem(void) 342 { 343 ppc_md.progress = ppc_printk_progress; 344 mark_initmem_nx(); 345 static_branch_enable(&init_mem_is_free); 346 free_initmem_default(POISON_FREE_INITMEM); 347 ftrace_free_init_tramp(); 348 } 349 350 /* 351 * System memory should not be in /proc/iomem but various tools expect it 352 * (eg kdump). 353 */ 354 static int __init add_system_ram_resources(void) 355 { 356 phys_addr_t start, end; 357 u64 i; 358 359 for_each_mem_range(i, &start, &end) { 360 struct resource *res; 361 362 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 363 WARN_ON(!res); 364 365 if (res) { 366 res->name = "System RAM"; 367 res->start = start; 368 /* 369 * In memblock, end points to the first byte after 370 * the range while in resourses, end points to the 371 * last byte in the range. 372 */ 373 res->end = end - 1; 374 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 375 WARN_ON(request_resource(&iomem_resource, res) < 0); 376 } 377 } 378 379 return 0; 380 } 381 subsys_initcall(add_system_ram_resources); 382 383 #ifdef CONFIG_STRICT_DEVMEM 384 /* 385 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 386 * is valid. The argument is a physical page number. 387 * 388 * Access has to be given to non-kernel-ram areas as well, these contain the 389 * PCI mmio resources as well as potential bios/acpi data regions. 390 */ 391 int devmem_is_allowed(unsigned long pfn) 392 { 393 if (page_is_rtas_user_buf(pfn)) 394 return 1; 395 if (iomem_is_exclusive(PFN_PHYS(pfn))) 396 return 0; 397 if (!page_is_ram(pfn)) 398 return 1; 399 return 0; 400 } 401 #endif /* CONFIG_STRICT_DEVMEM */ 402 403 /* 404 * This is defined in kernel/resource.c but only powerpc needs to export it, for 405 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed. 406 */ 407 EXPORT_SYMBOL_GPL(walk_system_ram_range); 408