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