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 30 #include <mm/mmu_decl.h> 31 32 unsigned long long memory_limit; 33 34 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 35 EXPORT_SYMBOL(empty_zero_page); 36 37 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 38 unsigned long size, pgprot_t vma_prot) 39 { 40 if (ppc_md.phys_mem_access_prot) 41 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 42 43 if (!page_is_ram(pfn)) 44 vma_prot = pgprot_noncached(vma_prot); 45 46 return vma_prot; 47 } 48 EXPORT_SYMBOL(phys_mem_access_prot); 49 50 #ifdef CONFIG_MEMORY_HOTPLUG 51 static DEFINE_MUTEX(linear_mapping_mutex); 52 53 #ifdef CONFIG_NUMA 54 int memory_add_physaddr_to_nid(u64 start) 55 { 56 return hot_add_scn_to_nid(start); 57 } 58 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); 59 #endif 60 61 int __weak create_section_mapping(unsigned long start, unsigned long end, 62 int nid, pgprot_t prot) 63 { 64 return -ENODEV; 65 } 66 67 int __weak remove_section_mapping(unsigned long start, unsigned long end) 68 { 69 return -ENODEV; 70 } 71 72 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size, 73 struct mhp_params *params) 74 { 75 int rc; 76 77 start = (unsigned long)__va(start); 78 mutex_lock(&linear_mapping_mutex); 79 rc = create_section_mapping(start, start + size, nid, 80 params->pgprot); 81 mutex_unlock(&linear_mapping_mutex); 82 if (rc) { 83 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n", 84 start, start + size, rc); 85 return -EFAULT; 86 } 87 return 0; 88 } 89 90 void __ref arch_remove_linear_mapping(u64 start, u64 size) 91 { 92 int ret; 93 94 /* Remove htab bolted mappings for this section of memory */ 95 start = (unsigned long)__va(start); 96 97 mutex_lock(&linear_mapping_mutex); 98 ret = remove_section_mapping(start, start + size); 99 mutex_unlock(&linear_mapping_mutex); 100 if (ret) 101 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n", 102 start, start + size, ret); 103 104 /* Ensure all vmalloc mappings are flushed in case they also 105 * hit that section of memory 106 */ 107 vm_unmap_aliases(); 108 } 109 110 /* 111 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need 112 * updating. 113 */ 114 static void update_end_of_memory_vars(u64 start, u64 size) 115 { 116 unsigned long end_pfn = PFN_UP(start + size); 117 118 if (end_pfn > max_pfn) { 119 max_pfn = end_pfn; 120 max_low_pfn = end_pfn; 121 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; 122 } 123 } 124 125 int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, 126 struct mhp_params *params) 127 { 128 int ret; 129 130 ret = __add_pages(nid, start_pfn, nr_pages, params); 131 if (ret) 132 return ret; 133 134 /* update max_pfn, max_low_pfn and high_memory */ 135 update_end_of_memory_vars(start_pfn << PAGE_SHIFT, 136 nr_pages << PAGE_SHIFT); 137 138 return ret; 139 } 140 141 int __ref arch_add_memory(int nid, u64 start, u64 size, 142 struct mhp_params *params) 143 { 144 unsigned long start_pfn = start >> PAGE_SHIFT; 145 unsigned long nr_pages = size >> PAGE_SHIFT; 146 int rc; 147 148 rc = arch_create_linear_mapping(nid, start, size, params); 149 if (rc) 150 return rc; 151 rc = add_pages(nid, start_pfn, nr_pages, params); 152 if (rc) 153 arch_remove_linear_mapping(start, size); 154 return rc; 155 } 156 157 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 158 { 159 unsigned long start_pfn = start >> PAGE_SHIFT; 160 unsigned long nr_pages = size >> PAGE_SHIFT; 161 162 __remove_pages(start_pfn, nr_pages, altmap); 163 arch_remove_linear_mapping(start, size); 164 } 165 #endif 166 167 #ifndef CONFIG_NUMA 168 void __init mem_topology_setup(void) 169 { 170 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 171 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 172 #ifdef CONFIG_HIGHMEM 173 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 174 #endif 175 176 /* Place all memblock_regions in the same node and merge contiguous 177 * memblock_regions 178 */ 179 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 180 } 181 182 void __init initmem_init(void) 183 { 184 sparse_init(); 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_bits 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 static unsigned long max_zone_pfns[MAX_NR_ZONES]; 222 223 /* 224 * paging_init() sets up the page tables - in fact we've already done this. 225 */ 226 void __init paging_init(void) 227 { 228 unsigned long long total_ram = memblock_phys_mem_size(); 229 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 230 231 #ifdef CONFIG_HIGHMEM 232 unsigned long v = __fix_to_virt(FIX_KMAP_END); 233 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN); 234 235 for (; v < end; v += PAGE_SIZE) 236 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 237 238 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 239 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 240 #endif /* CONFIG_HIGHMEM */ 241 242 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 243 (unsigned long long)top_of_ram, total_ram); 244 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 245 (long int)((top_of_ram - total_ram) >> 20)); 246 247 /* 248 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 249 * powerbooks. 250 */ 251 if (IS_ENABLED(CONFIG_PPC32)) 252 zone_dma_bits = 30; 253 else 254 zone_dma_bits = 31; 255 256 #ifdef CONFIG_ZONE_DMA 257 max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 258 1UL << (zone_dma_bits - PAGE_SHIFT)); 259 #endif 260 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 261 #ifdef CONFIG_HIGHMEM 262 max_zone_pfns[ZONE_HIGHMEM] = max_pfn; 263 #endif 264 265 free_area_init(max_zone_pfns); 266 267 mark_nonram_nosave(); 268 } 269 270 void __init mem_init(void) 271 { 272 /* 273 * book3s is limited to 16 page sizes due to encoding this in 274 * a 4-bit field for slices. 275 */ 276 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 277 278 #ifdef CONFIG_SWIOTLB 279 /* 280 * Some platforms (e.g. 85xx) limit DMA-able memory way below 281 * 4G. We force memblock to bottom-up mode to ensure that the 282 * memory allocated in swiotlb_init() is DMA-able. 283 * As it's the last memblock allocation, no need to reset it 284 * back to to-down. 285 */ 286 memblock_set_bottom_up(true); 287 swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags); 288 #endif 289 290 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 291 set_max_mapnr(max_pfn); 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 static_branch_enable(&init_mem_is_free); 348 free_initmem_default(POISON_FREE_INITMEM); 349 ftrace_free_init_tramp(); 350 } 351 352 /* 353 * System memory should not be in /proc/iomem but various tools expect it 354 * (eg kdump). 355 */ 356 static int __init add_system_ram_resources(void) 357 { 358 phys_addr_t start, end; 359 u64 i; 360 361 for_each_mem_range(i, &start, &end) { 362 struct resource *res; 363 364 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 365 WARN_ON(!res); 366 367 if (res) { 368 res->name = "System RAM"; 369 res->start = start; 370 /* 371 * In memblock, end points to the first byte after 372 * the range while in resourses, end points to the 373 * last byte in the range. 374 */ 375 res->end = end - 1; 376 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 377 WARN_ON(request_resource(&iomem_resource, res) < 0); 378 } 379 } 380 381 return 0; 382 } 383 subsys_initcall(add_system_ram_resources); 384 385 #ifdef CONFIG_STRICT_DEVMEM 386 /* 387 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 388 * is valid. The argument is a physical page number. 389 * 390 * Access has to be given to non-kernel-ram areas as well, these contain the 391 * PCI mmio resources as well as potential bios/acpi data regions. 392 */ 393 int devmem_is_allowed(unsigned long pfn) 394 { 395 if (page_is_rtas_user_buf(pfn)) 396 return 1; 397 if (iomem_is_exclusive(PFN_PHYS(pfn))) 398 return 0; 399 if (!page_is_ram(pfn)) 400 return 1; 401 return 0; 402 } 403 #endif /* CONFIG_STRICT_DEVMEM */ 404 405 /* 406 * This is defined in kernel/resource.c but only powerpc needs to export it, for 407 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed. 408 */ 409 EXPORT_SYMBOL_GPL(walk_system_ram_range); 410