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/machdep.h> 21 #include <asm/rtas.h> 22 #include <asm/kasan.h> 23 #include <asm/svm.h> 24 25 #include <mm/mmu_decl.h> 26 27 unsigned long long memory_limit; 28 bool init_mem_is_free; 29 30 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 31 unsigned long size, pgprot_t vma_prot) 32 { 33 if (ppc_md.phys_mem_access_prot) 34 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 35 36 if (!page_is_ram(pfn)) 37 vma_prot = pgprot_noncached(vma_prot); 38 39 return vma_prot; 40 } 41 EXPORT_SYMBOL(phys_mem_access_prot); 42 43 #ifdef CONFIG_MEMORY_HOTPLUG 44 static DEFINE_MUTEX(linear_mapping_mutex); 45 46 #ifdef CONFIG_NUMA 47 int memory_add_physaddr_to_nid(u64 start) 48 { 49 return hot_add_scn_to_nid(start); 50 } 51 #endif 52 53 int __weak create_section_mapping(unsigned long start, unsigned long end, 54 int nid, pgprot_t prot) 55 { 56 return -ENODEV; 57 } 58 59 int __weak remove_section_mapping(unsigned long start, unsigned long end) 60 { 61 return -ENODEV; 62 } 63 64 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size, 65 struct mhp_params *params) 66 { 67 int rc; 68 69 start = (unsigned long)__va(start); 70 mutex_lock(&linear_mapping_mutex); 71 rc = create_section_mapping(start, start + size, nid, 72 params->pgprot); 73 mutex_unlock(&linear_mapping_mutex); 74 if (rc) { 75 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n", 76 start, start + size, rc); 77 return -EFAULT; 78 } 79 return 0; 80 } 81 82 void __ref arch_remove_linear_mapping(u64 start, u64 size) 83 { 84 int ret; 85 86 /* Remove htab bolted mappings for this section of memory */ 87 start = (unsigned long)__va(start); 88 89 mutex_lock(&linear_mapping_mutex); 90 ret = remove_section_mapping(start, start + size); 91 mutex_unlock(&linear_mapping_mutex); 92 if (ret) 93 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n", 94 start, start + size, ret); 95 96 /* Ensure all vmalloc mappings are flushed in case they also 97 * hit that section of memory 98 */ 99 vm_unmap_aliases(); 100 } 101 102 int __ref arch_add_memory(int nid, u64 start, u64 size, 103 struct mhp_params *params) 104 { 105 unsigned long start_pfn = start >> PAGE_SHIFT; 106 unsigned long nr_pages = size >> PAGE_SHIFT; 107 int rc; 108 109 rc = arch_create_linear_mapping(nid, start, size, params); 110 if (rc) 111 return rc; 112 rc = __add_pages(nid, start_pfn, nr_pages, params); 113 if (rc) 114 arch_remove_linear_mapping(start, size); 115 return rc; 116 } 117 118 void __ref arch_remove_memory(int nid, u64 start, u64 size, 119 struct vmem_altmap *altmap) 120 { 121 unsigned long start_pfn = start >> PAGE_SHIFT; 122 unsigned long nr_pages = size >> PAGE_SHIFT; 123 124 __remove_pages(start_pfn, nr_pages, altmap); 125 arch_remove_linear_mapping(start, size); 126 } 127 #endif 128 129 #ifndef CONFIG_NEED_MULTIPLE_NODES 130 void __init mem_topology_setup(void) 131 { 132 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 133 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 134 #ifdef CONFIG_HIGHMEM 135 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 136 #endif 137 138 /* Place all memblock_regions in the same node and merge contiguous 139 * memblock_regions 140 */ 141 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 142 } 143 144 void __init initmem_init(void) 145 { 146 sparse_init(); 147 } 148 149 /* mark pages that don't exist as nosave */ 150 static int __init mark_nonram_nosave(void) 151 { 152 unsigned long spfn, epfn, prev = 0; 153 int i; 154 155 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) { 156 if (prev && prev < spfn) 157 register_nosave_region(prev, spfn); 158 159 prev = epfn; 160 } 161 162 return 0; 163 } 164 #else /* CONFIG_NEED_MULTIPLE_NODES */ 165 static int __init mark_nonram_nosave(void) 166 { 167 return 0; 168 } 169 #endif 170 171 /* 172 * Zones usage: 173 * 174 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be 175 * everything else. GFP_DMA32 page allocations automatically fall back to 176 * ZONE_DMA. 177 * 178 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the 179 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU 180 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by 181 * ZONE_DMA. 182 */ 183 static unsigned long max_zone_pfns[MAX_NR_ZONES]; 184 185 /* 186 * paging_init() sets up the page tables - in fact we've already done this. 187 */ 188 void __init paging_init(void) 189 { 190 unsigned long long total_ram = memblock_phys_mem_size(); 191 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 192 193 #ifdef CONFIG_HIGHMEM 194 unsigned long v = __fix_to_virt(FIX_KMAP_END); 195 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN); 196 197 for (; v < end; v += PAGE_SIZE) 198 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 199 200 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 201 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 202 #endif /* CONFIG_HIGHMEM */ 203 204 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 205 (unsigned long long)top_of_ram, total_ram); 206 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 207 (long int)((top_of_ram - total_ram) >> 20)); 208 209 /* 210 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 211 * powerbooks. 212 */ 213 if (IS_ENABLED(CONFIG_PPC32)) 214 zone_dma_bits = 30; 215 else 216 zone_dma_bits = 31; 217 218 #ifdef CONFIG_ZONE_DMA 219 max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 220 1UL << (zone_dma_bits - PAGE_SHIFT)); 221 #endif 222 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 223 #ifdef CONFIG_HIGHMEM 224 max_zone_pfns[ZONE_HIGHMEM] = max_pfn; 225 #endif 226 227 free_area_init(max_zone_pfns); 228 229 mark_nonram_nosave(); 230 } 231 232 void __init mem_init(void) 233 { 234 /* 235 * book3s is limited to 16 page sizes due to encoding this in 236 * a 4-bit field for slices. 237 */ 238 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 239 240 #ifdef CONFIG_SWIOTLB 241 /* 242 * Some platforms (e.g. 85xx) limit DMA-able memory way below 243 * 4G. We force memblock to bottom-up mode to ensure that the 244 * memory allocated in swiotlb_init() is DMA-able. 245 * As it's the last memblock allocation, no need to reset it 246 * back to to-down. 247 */ 248 memblock_set_bottom_up(true); 249 if (is_secure_guest()) 250 svm_swiotlb_init(); 251 else 252 swiotlb_init(0); 253 #endif 254 255 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 256 set_max_mapnr(max_pfn); 257 258 kasan_late_init(); 259 260 memblock_free_all(); 261 262 #ifdef CONFIG_HIGHMEM 263 { 264 unsigned long pfn, highmem_mapnr; 265 266 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 267 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 268 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; 269 struct page *page = pfn_to_page(pfn); 270 if (!memblock_is_reserved(paddr)) 271 free_highmem_page(page); 272 } 273 } 274 #endif /* CONFIG_HIGHMEM */ 275 276 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP) 277 /* 278 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 279 * functions.... do it here for the non-smp case. 280 */ 281 per_cpu(next_tlbcam_idx, smp_processor_id()) = 282 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 283 #endif 284 285 #ifdef CONFIG_PPC32 286 pr_info("Kernel virtual memory layout:\n"); 287 #ifdef CONFIG_KASAN 288 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n", 289 KASAN_SHADOW_START, KASAN_SHADOW_END); 290 #endif 291 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 292 #ifdef CONFIG_HIGHMEM 293 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 294 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 295 #endif /* CONFIG_HIGHMEM */ 296 if (ioremap_bot != IOREMAP_TOP) 297 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 298 ioremap_bot, IOREMAP_TOP); 299 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 300 VMALLOC_START, VMALLOC_END); 301 #endif /* CONFIG_PPC32 */ 302 } 303 304 void free_initmem(void) 305 { 306 ppc_md.progress = ppc_printk_progress; 307 mark_initmem_nx(); 308 init_mem_is_free = true; 309 free_initmem_default(POISON_FREE_INITMEM); 310 } 311 312 /* 313 * System memory should not be in /proc/iomem but various tools expect it 314 * (eg kdump). 315 */ 316 static int __init add_system_ram_resources(void) 317 { 318 phys_addr_t start, end; 319 u64 i; 320 321 for_each_mem_range(i, &start, &end) { 322 struct resource *res; 323 324 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 325 WARN_ON(!res); 326 327 if (res) { 328 res->name = "System RAM"; 329 res->start = start; 330 /* 331 * In memblock, end points to the first byte after 332 * the range while in resourses, end points to the 333 * last byte in the range. 334 */ 335 res->end = end - 1; 336 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 337 WARN_ON(request_resource(&iomem_resource, res) < 0); 338 } 339 } 340 341 return 0; 342 } 343 subsys_initcall(add_system_ram_resources); 344 345 #ifdef CONFIG_STRICT_DEVMEM 346 /* 347 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 348 * is valid. The argument is a physical page number. 349 * 350 * Access has to be given to non-kernel-ram areas as well, these contain the 351 * PCI mmio resources as well as potential bios/acpi data regions. 352 */ 353 int devmem_is_allowed(unsigned long pfn) 354 { 355 if (page_is_rtas_user_buf(pfn)) 356 return 1; 357 if (iomem_is_exclusive(PFN_PHYS(pfn))) 358 return 0; 359 if (!page_is_ram(pfn)) 360 return 1; 361 return 0; 362 } 363 #endif /* CONFIG_STRICT_DEVMEM */ 364 365 /* 366 * This is defined in kernel/resource.c but only powerpc needs to export it, for 367 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed. 368 */ 369 EXPORT_SYMBOL_GPL(walk_system_ram_range); 370