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