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 #include <linux/execmem.h>
20 #include <linux/vmalloc.h>
21
22 #include <asm/swiotlb.h>
23 #include <asm/machdep.h>
24 #include <asm/rtas.h>
25 #include <asm/kasan.h>
26 #include <asm/svm.h>
27 #include <asm/mmzone.h>
28 #include <asm/ftrace.h>
29 #include <asm/code-patching.h>
30 #include <asm/setup.h>
31 #include <asm/fixmap.h>
32
33 #include <mm/mmu_decl.h>
34
35 unsigned long long memory_limit __initdata;
36
37 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
38 EXPORT_SYMBOL(empty_zero_page);
39
40 pgprot_t __phys_mem_access_prot(unsigned long pfn, unsigned long size,
41 pgprot_t vma_prot)
42 {
43 if (ppc_md.phys_mem_access_prot)
44 return ppc_md.phys_mem_access_prot(pfn, size, vma_prot);
45
46 if (!page_is_ram(pfn))
47 vma_prot = pgprot_noncached(vma_prot);
48
49 return vma_prot;
50 }
51 EXPORT_SYMBOL(__phys_mem_access_prot);
52
53 #ifdef CONFIG_MEMORY_HOTPLUG
54 static DEFINE_MUTEX(linear_mapping_mutex);
55
56 #ifdef CONFIG_NUMA
57 int memory_add_physaddr_to_nid(u64 start)
58 {
59 return hot_add_scn_to_nid(start);
60 }
61 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
62 #endif
63
64 int __weak create_section_mapping(unsigned long start, unsigned long end,
65 int nid, pgprot_t prot)
66 {
67 return -ENODEV;
68 }
69
70 int __weak remove_section_mapping(unsigned long start, unsigned long end)
71 {
72 return -ENODEV;
73 }
74
75 int __ref arch_create_linear_mapping(int nid, u64 start, u64 size,
76 struct mhp_params *params)
77 {
78 int rc;
79
80 start = (unsigned long)__va(start);
81 mutex_lock(&linear_mapping_mutex);
82 rc = create_section_mapping(start, start + size, nid,
83 params->pgprot);
84 mutex_unlock(&linear_mapping_mutex);
85 if (rc) {
86 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n",
87 start, start + size, rc);
88 return -EFAULT;
89 }
90 return 0;
91 }
92
93 void __ref arch_remove_linear_mapping(u64 start, u64 size)
94 {
95 int ret;
96
97 /* Remove htab bolted mappings for this section of memory */
98 start = (unsigned long)__va(start);
99
100 mutex_lock(&linear_mapping_mutex);
101 ret = remove_section_mapping(start, start + size);
102 mutex_unlock(&linear_mapping_mutex);
103 if (ret)
104 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n",
105 start, start + size, ret);
106
107 /* Ensure all vmalloc mappings are flushed in case they also
108 * hit that section of memory
109 */
110 vm_unmap_aliases();
111 }
112
113 /*
114 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
115 * updating.
116 */
117 static void update_end_of_memory_vars(u64 start, u64 size)
118 {
119 unsigned long end_pfn = PFN_UP(start + size);
120
121 if (end_pfn > max_pfn) {
122 max_pfn = end_pfn;
123 max_low_pfn = end_pfn;
124 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
125 }
126 }
127
128 int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
129 struct mhp_params *params)
130 {
131 int ret;
132
133 ret = __add_pages(nid, start_pfn, nr_pages, params);
134 if (ret)
135 return ret;
136
137 /* update max_pfn, max_low_pfn and high_memory */
138 update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
139 nr_pages << PAGE_SHIFT);
140
141 return ret;
142 }
143
144 int __ref arch_add_memory(int nid, u64 start, u64 size,
145 struct mhp_params *params)
146 {
147 unsigned long start_pfn = start >> PAGE_SHIFT;
148 unsigned long nr_pages = size >> PAGE_SHIFT;
149 int rc;
150
151 rc = arch_create_linear_mapping(nid, start, size, params);
152 if (rc)
153 return rc;
154 rc = add_pages(nid, start_pfn, nr_pages, params);
155 if (rc)
156 arch_remove_linear_mapping(start, size);
157 return rc;
158 }
159
160 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
161 {
162 unsigned long start_pfn = start >> PAGE_SHIFT;
163 unsigned long nr_pages = size >> PAGE_SHIFT;
164
165 __remove_pages(start_pfn, nr_pages, altmap);
166 arch_remove_linear_mapping(start, size);
167 }
168 #endif
169
170 #ifndef CONFIG_NUMA
171 void __init mem_topology_setup(void)
172 {
173 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
174 min_low_pfn = MEMORY_START >> PAGE_SHIFT;
175 #ifdef CONFIG_HIGHMEM
176 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
177 #endif
178
179 /* Place all memblock_regions in the same node and merge contiguous
180 * memblock_regions
181 */
182 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
183 }
184
185 void __init initmem_init(void)
186 {
187 sparse_init();
188 }
189
190 /* mark pages that don't exist as nosave */
191 static int __init mark_nonram_nosave(void)
192 {
193 unsigned long spfn, epfn, prev = 0;
194 int i;
195
196 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) {
197 if (prev && prev < spfn)
198 register_nosave_region(prev, spfn);
199
200 prev = epfn;
201 }
202
203 return 0;
204 }
205 #else /* CONFIG_NUMA */
206 static int __init mark_nonram_nosave(void)
207 {
208 return 0;
209 }
210 #endif
211
212 /*
213 * Zones usage:
214 *
215 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be
216 * everything else. GFP_DMA32 page allocations automatically fall back to
217 * ZONE_DMA.
218 *
219 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the
220 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU
221 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by
222 * ZONE_DMA.
223 */
224 static unsigned long max_zone_pfns[MAX_NR_ZONES];
225
226 /*
227 * paging_init() sets up the page tables - in fact we've already done this.
228 */
229 void __init paging_init(void)
230 {
231 unsigned long long total_ram = memblock_phys_mem_size();
232 phys_addr_t top_of_ram = memblock_end_of_DRAM();
233
234 #ifdef CONFIG_HIGHMEM
235 unsigned long v = __fix_to_virt(FIX_KMAP_END);
236 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN);
237
238 for (; v < end; v += PAGE_SIZE)
239 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */
240
241 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */
242 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
243 #endif /* CONFIG_HIGHMEM */
244
245 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
246 (unsigned long long)top_of_ram, total_ram);
247 printk(KERN_DEBUG "Memory hole size: %ldMB\n",
248 (long int)((top_of_ram - total_ram) >> 20));
249
250 /*
251 * Allow 30-bit DMA for very limited Broadcom wifi chips on many
252 * powerbooks.
253 */
254 if (IS_ENABLED(CONFIG_PPC32))
255 zone_dma_bits = 30;
256 else
257 zone_dma_bits = 31;
258
259 #ifdef CONFIG_ZONE_DMA
260 max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
261 1UL << (zone_dma_bits - PAGE_SHIFT));
262 #endif
263 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
264 #ifdef CONFIG_HIGHMEM
265 max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
266 #endif
267
268 free_area_init(max_zone_pfns);
269
270 mark_nonram_nosave();
271 }
272
273 void __init mem_init(void)
274 {
275 /*
276 * book3s is limited to 16 page sizes due to encoding this in
277 * a 4-bit field for slices.
278 */
279 BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
280
281 #ifdef CONFIG_SWIOTLB
282 /*
283 * Some platforms (e.g. 85xx) limit DMA-able memory way below
284 * 4G. We force memblock to bottom-up mode to ensure that the
285 * memory allocated in swiotlb_init() is DMA-able.
286 * As it's the last memblock allocation, no need to reset it
287 * back to to-down.
288 */
289 memblock_set_bottom_up(true);
290 swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags);
291 #endif
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 free_initmem_default(POISON_FREE_INITMEM);
348 ftrace_free_init_tramp();
349 }
350
351 /*
352 * System memory should not be in /proc/iomem but various tools expect it
353 * (eg kdump).
354 */
355 static int __init add_system_ram_resources(void)
356 {
357 phys_addr_t start, end;
358 u64 i;
359
360 for_each_mem_range(i, &start, &end) {
361 struct resource *res;
362
363 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
364 WARN_ON(!res);
365
366 if (res) {
367 res->name = "System RAM";
368 res->start = start;
369 /*
370 * In memblock, end points to the first byte after
371 * the range while in resourses, end points to the
372 * last byte in the range.
373 */
374 res->end = end - 1;
375 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
376 WARN_ON(request_resource(&iomem_resource, res) < 0);
377 }
378 }
379
380 return 0;
381 }
382 subsys_initcall(add_system_ram_resources);
383
384 #ifdef CONFIG_STRICT_DEVMEM
385 /*
386 * devmem_is_allowed(): check to see if /dev/mem access to a certain address
387 * is valid. The argument is a physical page number.
388 *
389 * Access has to be given to non-kernel-ram areas as well, these contain the
390 * PCI mmio resources as well as potential bios/acpi data regions.
391 */
392 int devmem_is_allowed(unsigned long pfn)
393 {
394 if (page_is_rtas_user_buf(pfn))
395 return 1;
396 if (iomem_is_exclusive(PFN_PHYS(pfn)))
397 return 0;
398 if (!page_is_ram(pfn))
399 return 1;
400 return 0;
401 }
402 #endif /* CONFIG_STRICT_DEVMEM */
403
404 /*
405 * This is defined in kernel/resource.c but only powerpc needs to export it, for
406 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed.
407 */
408 EXPORT_SYMBOL_GPL(walk_system_ram_range);
409
410 #ifdef CONFIG_EXECMEM
411 static struct execmem_info execmem_info __ro_after_init;
412
413 struct execmem_info __init *execmem_arch_setup(void)
414 {
415 pgprot_t kprobes_prot = strict_module_rwx_enabled() ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;
416 pgprot_t prot = strict_module_rwx_enabled() ? PAGE_KERNEL : PAGE_KERNEL_EXEC;
417 unsigned long fallback_start = 0, fallback_end = 0;
418 unsigned long start, end;
419
420 /*
421 * BOOK3S_32 and 8xx define MODULES_VADDR for text allocations and
422 * allow allocating data in the entire vmalloc space
423 */
424 #ifdef MODULES_VADDR
425 unsigned long limit = (unsigned long)_etext - SZ_32M;
426
427 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
428
429 /* First try within 32M limit from _etext to avoid branch trampolines */
430 if (MODULES_VADDR < PAGE_OFFSET && MODULES_END > limit) {
431 start = limit;
432 fallback_start = MODULES_VADDR;
433 fallback_end = MODULES_END;
434 } else {
435 start = MODULES_VADDR;
436 }
437
438 end = MODULES_END;
439 #else
440 start = VMALLOC_START;
441 end = VMALLOC_END;
442 #endif
443
444 execmem_info = (struct execmem_info){
445 .ranges = {
446 [EXECMEM_DEFAULT] = {
447 .start = start,
448 .end = end,
449 .pgprot = prot,
450 .alignment = 1,
451 .fallback_start = fallback_start,
452 .fallback_end = fallback_end,
453 },
454 [EXECMEM_KPROBES] = {
455 .start = VMALLOC_START,
456 .end = VMALLOC_END,
457 .pgprot = kprobes_prot,
458 .alignment = 1,
459 },
460 [EXECMEM_MODULE_DATA] = {
461 .start = VMALLOC_START,
462 .end = VMALLOC_END,
463 .pgprot = PAGE_KERNEL,
464 .alignment = 1,
465 },
466 },
467 };
468
469 return &execmem_info;
470 }
471 #endif /* CONFIG_EXECMEM */
472
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