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/sparsemem.h> 24 #include <asm/svm.h> 25 26 #include <mm/mmu_decl.h> 27 28 unsigned long long memory_limit; 29 bool init_mem_is_free; 30 31 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 32 EXPORT_SYMBOL(empty_zero_page); 33 34 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 35 unsigned long size, pgprot_t vma_prot) 36 { 37 if (ppc_md.phys_mem_access_prot) 38 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 39 40 if (!page_is_ram(pfn)) 41 vma_prot = pgprot_noncached(vma_prot); 42 43 return vma_prot; 44 } 45 EXPORT_SYMBOL(phys_mem_access_prot); 46 47 #ifdef CONFIG_MEMORY_HOTPLUG 48 static DEFINE_MUTEX(linear_mapping_mutex); 49 50 #ifdef CONFIG_NUMA 51 int memory_add_physaddr_to_nid(u64 start) 52 { 53 return hot_add_scn_to_nid(start); 54 } 55 #endif 56 57 int __weak create_section_mapping(unsigned long start, unsigned long end, 58 int nid, pgprot_t prot) 59 { 60 return -ENODEV; 61 } 62 63 int __weak remove_section_mapping(unsigned long start, unsigned long end) 64 { 65 return -ENODEV; 66 } 67 68 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size, 69 struct mhp_params *params) 70 { 71 int rc; 72 73 start = (unsigned long)__va(start); 74 mutex_lock(&linear_mapping_mutex); 75 rc = create_section_mapping(start, start + size, nid, 76 params->pgprot); 77 mutex_unlock(&linear_mapping_mutex); 78 if (rc) { 79 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n", 80 start, start + size, rc); 81 return -EFAULT; 82 } 83 return 0; 84 } 85 86 void __ref arch_remove_linear_mapping(u64 start, u64 size) 87 { 88 int ret; 89 90 /* Remove htab bolted mappings for this section of memory */ 91 start = (unsigned long)__va(start); 92 93 mutex_lock(&linear_mapping_mutex); 94 ret = remove_section_mapping(start, start + size); 95 mutex_unlock(&linear_mapping_mutex); 96 if (ret) 97 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n", 98 start, start + size, ret); 99 100 /* Ensure all vmalloc mappings are flushed in case they also 101 * hit that section of memory 102 */ 103 vm_unmap_aliases(); 104 } 105 106 int __ref arch_add_memory(int nid, u64 start, u64 size, 107 struct mhp_params *params) 108 { 109 unsigned long start_pfn = start >> PAGE_SHIFT; 110 unsigned long nr_pages = size >> PAGE_SHIFT; 111 int rc; 112 113 rc = arch_create_linear_mapping(nid, start, size, params); 114 if (rc) 115 return rc; 116 rc = __add_pages(nid, start_pfn, nr_pages, params); 117 if (rc) 118 arch_remove_linear_mapping(start, size); 119 return rc; 120 } 121 122 void __ref arch_remove_memory(int nid, u64 start, u64 size, 123 struct vmem_altmap *altmap) 124 { 125 unsigned long start_pfn = start >> PAGE_SHIFT; 126 unsigned long nr_pages = size >> PAGE_SHIFT; 127 128 __remove_pages(start_pfn, nr_pages, altmap); 129 arch_remove_linear_mapping(start, size); 130 } 131 #endif 132 133 #ifndef CONFIG_NUMA 134 void __init mem_topology_setup(void) 135 { 136 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; 137 min_low_pfn = MEMORY_START >> PAGE_SHIFT; 138 #ifdef CONFIG_HIGHMEM 139 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; 140 #endif 141 142 /* Place all memblock_regions in the same node and merge contiguous 143 * memblock_regions 144 */ 145 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 146 } 147 148 void __init initmem_init(void) 149 { 150 sparse_init(); 151 } 152 153 /* mark pages that don't exist as nosave */ 154 static int __init mark_nonram_nosave(void) 155 { 156 unsigned long spfn, epfn, prev = 0; 157 int i; 158 159 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) { 160 if (prev && prev < spfn) 161 register_nosave_region(prev, spfn); 162 163 prev = epfn; 164 } 165 166 return 0; 167 } 168 #else /* CONFIG_NUMA */ 169 static int __init mark_nonram_nosave(void) 170 { 171 return 0; 172 } 173 #endif 174 175 /* 176 * Zones usage: 177 * 178 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be 179 * everything else. GFP_DMA32 page allocations automatically fall back to 180 * ZONE_DMA. 181 * 182 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the 183 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU 184 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by 185 * ZONE_DMA. 186 */ 187 static unsigned long max_zone_pfns[MAX_NR_ZONES]; 188 189 /* 190 * paging_init() sets up the page tables - in fact we've already done this. 191 */ 192 void __init paging_init(void) 193 { 194 unsigned long long total_ram = memblock_phys_mem_size(); 195 phys_addr_t top_of_ram = memblock_end_of_DRAM(); 196 197 #ifdef CONFIG_HIGHMEM 198 unsigned long v = __fix_to_virt(FIX_KMAP_END); 199 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN); 200 201 for (; v < end; v += PAGE_SIZE) 202 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */ 203 204 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */ 205 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 206 #endif /* CONFIG_HIGHMEM */ 207 208 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", 209 (unsigned long long)top_of_ram, total_ram); 210 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 211 (long int)((top_of_ram - total_ram) >> 20)); 212 213 /* 214 * Allow 30-bit DMA for very limited Broadcom wifi chips on many 215 * powerbooks. 216 */ 217 if (IS_ENABLED(CONFIG_PPC32)) 218 zone_dma_bits = 30; 219 else 220 zone_dma_bits = 31; 221 222 #ifdef CONFIG_ZONE_DMA 223 max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 224 1UL << (zone_dma_bits - PAGE_SHIFT)); 225 #endif 226 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 227 #ifdef CONFIG_HIGHMEM 228 max_zone_pfns[ZONE_HIGHMEM] = max_pfn; 229 #endif 230 231 free_area_init(max_zone_pfns); 232 233 mark_nonram_nosave(); 234 } 235 236 void __init mem_init(void) 237 { 238 /* 239 * book3s is limited to 16 page sizes due to encoding this in 240 * a 4-bit field for slices. 241 */ 242 BUILD_BUG_ON(MMU_PAGE_COUNT > 16); 243 244 #ifdef CONFIG_SWIOTLB 245 /* 246 * Some platforms (e.g. 85xx) limit DMA-able memory way below 247 * 4G. We force memblock to bottom-up mode to ensure that the 248 * memory allocated in swiotlb_init() is DMA-able. 249 * As it's the last memblock allocation, no need to reset it 250 * back to to-down. 251 */ 252 memblock_set_bottom_up(true); 253 if (is_secure_guest()) 254 svm_swiotlb_init(); 255 else 256 swiotlb_init(0); 257 #endif 258 259 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 260 set_max_mapnr(max_pfn); 261 262 kasan_late_init(); 263 264 memblock_free_all(); 265 266 #ifdef CONFIG_HIGHMEM 267 { 268 unsigned long pfn, highmem_mapnr; 269 270 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; 271 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 272 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; 273 struct page *page = pfn_to_page(pfn); 274 if (!memblock_is_reserved(paddr)) 275 free_highmem_page(page); 276 } 277 } 278 #endif /* CONFIG_HIGHMEM */ 279 280 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP) 281 /* 282 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up 283 * functions.... do it here for the non-smp case. 284 */ 285 per_cpu(next_tlbcam_idx, smp_processor_id()) = 286 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; 287 #endif 288 289 #ifdef CONFIG_PPC32 290 pr_info("Kernel virtual memory layout:\n"); 291 #ifdef CONFIG_KASAN 292 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n", 293 KASAN_SHADOW_START, KASAN_SHADOW_END); 294 #endif 295 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 296 #ifdef CONFIG_HIGHMEM 297 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 298 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 299 #endif /* CONFIG_HIGHMEM */ 300 if (ioremap_bot != IOREMAP_TOP) 301 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 302 ioremap_bot, IOREMAP_TOP); 303 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 304 VMALLOC_START, VMALLOC_END); 305 #ifdef MODULES_VADDR 306 pr_info(" * 0x%08lx..0x%08lx : modules\n", 307 MODULES_VADDR, MODULES_END); 308 #endif 309 #endif /* CONFIG_PPC32 */ 310 } 311 312 void free_initmem(void) 313 { 314 ppc_md.progress = ppc_printk_progress; 315 mark_initmem_nx(); 316 init_mem_is_free = true; 317 free_initmem_default(POISON_FREE_INITMEM); 318 } 319 320 /* 321 * System memory should not be in /proc/iomem but various tools expect it 322 * (eg kdump). 323 */ 324 static int __init add_system_ram_resources(void) 325 { 326 phys_addr_t start, end; 327 u64 i; 328 329 for_each_mem_range(i, &start, &end) { 330 struct resource *res; 331 332 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 333 WARN_ON(!res); 334 335 if (res) { 336 res->name = "System RAM"; 337 res->start = start; 338 /* 339 * In memblock, end points to the first byte after 340 * the range while in resourses, end points to the 341 * last byte in the range. 342 */ 343 res->end = end - 1; 344 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 345 WARN_ON(request_resource(&iomem_resource, res) < 0); 346 } 347 } 348 349 return 0; 350 } 351 subsys_initcall(add_system_ram_resources); 352 353 #ifdef CONFIG_STRICT_DEVMEM 354 /* 355 * devmem_is_allowed(): check to see if /dev/mem access to a certain address 356 * is valid. The argument is a physical page number. 357 * 358 * Access has to be given to non-kernel-ram areas as well, these contain the 359 * PCI mmio resources as well as potential bios/acpi data regions. 360 */ 361 int devmem_is_allowed(unsigned long pfn) 362 { 363 if (page_is_rtas_user_buf(pfn)) 364 return 1; 365 if (iomem_is_exclusive(PFN_PHYS(pfn))) 366 return 0; 367 if (!page_is_ram(pfn)) 368 return 1; 369 return 0; 370 } 371 #endif /* CONFIG_STRICT_DEVMEM */ 372 373 /* 374 * This is defined in kernel/resource.c but only powerpc needs to export it, for 375 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed. 376 */ 377 EXPORT_SYMBOL_GPL(walk_system_ram_range); 378