1 // SPDX-License-Identifier: GPL-2.0
2 #define boot_fmt(fmt) "physmem: " fmt
3 #include <linux/processor.h>
4 #include <linux/errno.h>
5 #include <linux/init.h>
6 #include <asm/physmem_info.h>
7 #include <asm/stacktrace.h>
8 #include <asm/boot_data.h>
9 #include <asm/sparsemem.h>
10 #include <asm/sections.h>
11 #include <asm/setup.h>
12 #include <asm/sclp.h>
13 #include <asm/asm.h>
14 #include <asm/uv.h>
15 #include "decompressor.h"
16 #include "boot.h"
17 
18 struct physmem_info __bootdata(physmem_info);
19 static unsigned int physmem_alloc_ranges;
20 static unsigned long physmem_alloc_pos;
21 
22 /* up to 256 storage elements, 1020 subincrements each */
23 #define ENTRIES_EXTENDED_MAX						       \
24 	(256 * (1020 / 2) * sizeof(struct physmem_range))
25 
26 static struct physmem_range *__get_physmem_range_ptr(u32 n)
27 {
28 	if (n < MEM_INLINED_ENTRIES)
29 		return &physmem_info.online[n];
30 	if (unlikely(!physmem_info.online_extended)) {
31 		physmem_info.online_extended = (struct physmem_range *)physmem_alloc_range(
32 			RR_MEM_DETECT_EXT, ENTRIES_EXTENDED_MAX, sizeof(long), 0,
33 			physmem_alloc_pos, true);
34 	}
35 	return &physmem_info.online_extended[n - MEM_INLINED_ENTRIES];
36 }
37 
38 /*
39  * sequential calls to add_physmem_online_range with adjacent memory ranges
40  * are merged together into single memory range.
41  */
42 void add_physmem_online_range(u64 start, u64 end)
43 {
44 	struct physmem_range *range;
45 
46 	if (physmem_info.range_count) {
47 		range = __get_physmem_range_ptr(physmem_info.range_count - 1);
48 		if (range->end == start) {
49 			range->end = end;
50 			return;
51 		}
52 	}
53 
54 	range = __get_physmem_range_ptr(physmem_info.range_count);
55 	range->start = start;
56 	range->end = end;
57 	physmem_info.range_count++;
58 }
59 
60 static int __diag260(unsigned long rx1, unsigned long rx2)
61 {
62 	union register_pair rx;
63 	int cc, exception;
64 	unsigned long ry;
65 
66 	rx.even = rx1;
67 	rx.odd	= rx2;
68 	ry = 0x10; /* storage configuration */
69 	exception = 1;
70 	asm_inline volatile(
71 		"	diag	%[rx],%[ry],0x260\n"
72 		"0:	lhi	%[exc],0\n"
73 		"1:\n"
74 		CC_IPM(cc)
75 		EX_TABLE(0b, 1b)
76 		: CC_OUT(cc, cc), [exc] "+d" (exception), [ry] "+d" (ry)
77 		: [rx] "d" (rx.pair)
78 		: CC_CLOBBER_LIST("memory"));
79 	cc = exception ? -1 : CC_TRANSFORM(cc);
80 	return cc == 0 ? ry : -1;
81 }
82 
83 static int diag260(void)
84 {
85 	int rc, i;
86 
87 	struct {
88 		unsigned long start;
89 		unsigned long end;
90 	} storage_extents[8] __aligned(16); /* VM supports up to 8 extends */
91 
92 	memset(storage_extents, 0, sizeof(storage_extents));
93 	rc = __diag260((unsigned long)storage_extents, sizeof(storage_extents));
94 	if (rc == -1)
95 		return -1;
96 
97 	for (i = 0; i < min_t(int, rc, ARRAY_SIZE(storage_extents)); i++)
98 		add_physmem_online_range(storage_extents[i].start, storage_extents[i].end + 1);
99 	return 0;
100 }
101 
102 #define DIAG500_SC_STOR_LIMIT 4
103 
104 static int diag500_storage_limit(unsigned long *max_physmem_end)
105 {
106 	unsigned long storage_limit;
107 
108 	asm_inline volatile(
109 		"	lghi	%%r1,%[subcode]\n"
110 		"	lghi	%%r2,0\n"
111 		"	diag	%%r2,%%r4,0x500\n"
112 		"0:	lgr	%[slimit],%%r2\n"
113 		EX_TABLE(0b, 0b)
114 		: [slimit] "=d" (storage_limit)
115 		: [subcode] "i" (DIAG500_SC_STOR_LIMIT)
116 		: "memory", "1", "2");
117 	if (!storage_limit)
118 		return -EINVAL;
119 	/* Convert inclusive end to exclusive end */
120 	*max_physmem_end = storage_limit + 1;
121 	return 0;
122 }
123 
124 static int tprot(unsigned long addr)
125 {
126 	int cc, exception;
127 
128 	exception = 1;
129 	asm_inline volatile(
130 		"	tprot	0(%[addr]),0\n"
131 		"0:	lhi	%[exc],0\n"
132 		"1:\n"
133 		CC_IPM(cc)
134 		EX_TABLE(0b, 1b)
135 		: CC_OUT(cc, cc), [exc] "+d" (exception)
136 		: [addr] "a" (addr)
137 		: CC_CLOBBER_LIST("memory"));
138 	cc = exception ? -EFAULT : CC_TRANSFORM(cc);
139 	return cc;
140 }
141 
142 static unsigned long search_mem_end(void)
143 {
144 	unsigned long range = 1 << (MAX_PHYSMEM_BITS - 20); /* in 1MB blocks */
145 	unsigned long offset = 0;
146 	unsigned long pivot;
147 
148 	while (range > 1) {
149 		range >>= 1;
150 		pivot = offset + range;
151 		if (!tprot(pivot << 20))
152 			offset = pivot;
153 	}
154 	return (offset + 1) << 20;
155 }
156 
157 unsigned long detect_max_physmem_end(void)
158 {
159 	unsigned long max_physmem_end = 0;
160 
161 	if (!diag500_storage_limit(&max_physmem_end)) {
162 		physmem_info.info_source = MEM_DETECT_DIAG500_STOR_LIMIT;
163 	} else if (!sclp_early_get_memsize(&max_physmem_end)) {
164 		physmem_info.info_source = MEM_DETECT_SCLP_READ_INFO;
165 	} else {
166 		max_physmem_end = search_mem_end();
167 		physmem_info.info_source = MEM_DETECT_BIN_SEARCH;
168 	}
169 	boot_debug("Max physical memory: 0x%016lx (info source: %s)\n", max_physmem_end,
170 		   get_physmem_info_source());
171 	return max_physmem_end;
172 }
173 
174 void detect_physmem_online_ranges(unsigned long max_physmem_end)
175 {
176 	unsigned long start, end;
177 	int i;
178 
179 	if (!sclp_early_read_storage_info()) {
180 		physmem_info.info_source = MEM_DETECT_SCLP_STOR_INFO;
181 	} else if (physmem_info.info_source == MEM_DETECT_DIAG500_STOR_LIMIT) {
182 		unsigned long online_end;
183 
184 		if (!sclp_early_get_memsize(&online_end)) {
185 			physmem_info.info_source = MEM_DETECT_SCLP_READ_INFO;
186 			add_physmem_online_range(0, online_end);
187 		}
188 	} else if (!diag260()) {
189 		physmem_info.info_source = MEM_DETECT_DIAG260;
190 	} else if (max_physmem_end) {
191 		add_physmem_online_range(0, max_physmem_end);
192 	}
193 	boot_debug("Online memory ranges (info source: %s):\n", get_physmem_info_source());
194 	for_each_physmem_online_range(i, &start, &end)
195 		boot_debug(" online [%d]:   0x%016lx-0x%016lx\n", i, start, end);
196 }
197 
198 void physmem_set_usable_limit(unsigned long limit)
199 {
200 	physmem_info.usable = limit;
201 	physmem_alloc_pos = limit;
202 	boot_debug("Usable memory limit: 0x%016lx\n", limit);
203 }
204 
205 static void die_oom(unsigned long size, unsigned long align, unsigned long min, unsigned long max)
206 {
207 	unsigned long start, end, total_mem = 0, total_reserved_mem = 0;
208 	struct reserved_range *range;
209 	enum reserved_range_type t;
210 	int i;
211 
212 	boot_emerg("Linux version %s\n", kernel_version);
213 	if (!is_prot_virt_guest() && early_command_line[0])
214 		boot_emerg("Kernel command line: %s\n", early_command_line);
215 	boot_emerg("Out of memory allocating %lu bytes 0x%lx aligned in range %lx:%lx\n",
216 		   size, align, min, max);
217 	boot_emerg("Reserved memory ranges:\n");
218 	for_each_physmem_reserved_range(t, range, &start, &end) {
219 		boot_emerg("%016lx %016lx %s\n", start, end, get_rr_type_name(t));
220 		total_reserved_mem += end - start;
221 	}
222 	boot_emerg("Usable online memory ranges (info source: %s [%d]):\n",
223 		   get_physmem_info_source(), physmem_info.info_source);
224 	for_each_physmem_usable_range(i, &start, &end) {
225 		boot_emerg("%016lx %016lx\n", start, end);
226 		total_mem += end - start;
227 	}
228 	boot_emerg("Usable online memory total: %lu Reserved: %lu Free: %lu\n",
229 		   total_mem, total_reserved_mem,
230 		   total_mem > total_reserved_mem ? total_mem - total_reserved_mem : 0);
231 	print_stacktrace(current_frame_address());
232 	boot_emerg(" -- System halted\n");
233 	disabled_wait();
234 }
235 
236 static void _physmem_reserve(enum reserved_range_type type, unsigned long addr, unsigned long size)
237 {
238 	physmem_info.reserved[type].start = addr;
239 	physmem_info.reserved[type].end = addr + size;
240 }
241 
242 void physmem_reserve(enum reserved_range_type type, unsigned long addr, unsigned long size)
243 {
244 	_physmem_reserve(type, addr, size);
245 	boot_debug("%-14s 0x%016lx-0x%016lx %s\n", "Reserve:", addr, addr + size,
246 		   get_rr_type_name(type));
247 }
248 
249 void physmem_free(enum reserved_range_type type)
250 {
251 	boot_debug("%-14s 0x%016lx-0x%016lx %s\n", "Free:", physmem_info.reserved[type].start,
252 		   physmem_info.reserved[type].end, get_rr_type_name(type));
253 	physmem_info.reserved[type].start = 0;
254 	physmem_info.reserved[type].end = 0;
255 }
256 
257 static bool __physmem_alloc_intersects(unsigned long addr, unsigned long size,
258 				       unsigned long *intersection_start)
259 {
260 	unsigned long res_addr, res_size;
261 	int t;
262 
263 	for (t = 0; t < RR_MAX; t++) {
264 		if (!get_physmem_reserved(t, &res_addr, &res_size))
265 			continue;
266 		if (intersects(addr, size, res_addr, res_size)) {
267 			*intersection_start = res_addr;
268 			return true;
269 		}
270 	}
271 	return ipl_report_certs_intersects(addr, size, intersection_start);
272 }
273 
274 static unsigned long __physmem_alloc_range(unsigned long size, unsigned long align,
275 					   unsigned long min, unsigned long max,
276 					   unsigned int from_ranges, unsigned int *ranges_left,
277 					   bool die_on_oom)
278 {
279 	unsigned int nranges = from_ranges ?: physmem_info.range_count;
280 	unsigned long range_start, range_end;
281 	unsigned long intersection_start;
282 	unsigned long addr, pos = max;
283 
284 	align = max(align, 8UL);
285 	while (nranges) {
286 		__get_physmem_range(nranges - 1, &range_start, &range_end, false);
287 		pos = min(range_end, pos);
288 
289 		if (round_up(min, align) + size > pos)
290 			break;
291 		addr = round_down(pos - size, align);
292 		if (range_start > addr) {
293 			nranges--;
294 			continue;
295 		}
296 		if (__physmem_alloc_intersects(addr, size, &intersection_start)) {
297 			pos = intersection_start;
298 			continue;
299 		}
300 
301 		if (ranges_left)
302 			*ranges_left = nranges;
303 		return addr;
304 	}
305 	if (die_on_oom)
306 		die_oom(size, align, min, max);
307 	return 0;
308 }
309 
310 unsigned long physmem_alloc_range(enum reserved_range_type type, unsigned long size,
311 				  unsigned long align, unsigned long min, unsigned long max,
312 				  bool die_on_oom)
313 {
314 	unsigned long addr;
315 
316 	max = min(max, physmem_alloc_pos);
317 	addr = __physmem_alloc_range(size, align, min, max, 0, NULL, die_on_oom);
318 	if (addr)
319 		_physmem_reserve(type, addr, size);
320 	boot_debug("%-14s 0x%016lx-0x%016lx %s\n", "Alloc range:", addr, addr + size,
321 		   get_rr_type_name(type));
322 	return addr;
323 }
324 
325 unsigned long physmem_alloc(enum reserved_range_type type, unsigned long size,
326 			    unsigned long align, bool die_on_oom)
327 {
328 	struct reserved_range *range = &physmem_info.reserved[type];
329 	struct reserved_range *new_range = NULL;
330 	unsigned int ranges_left;
331 	unsigned long addr;
332 
333 	addr = __physmem_alloc_range(size, align, 0, physmem_alloc_pos, physmem_alloc_ranges,
334 				     &ranges_left, die_on_oom);
335 	if (!addr)
336 		return 0;
337 	/* if not a consecutive allocation of the same type or first allocation */
338 	if (range->start != addr + size) {
339 		if (range->end) {
340 			addr = __physmem_alloc_range(sizeof(struct reserved_range), 0, 0,
341 						     physmem_alloc_pos, physmem_alloc_ranges,
342 						     &ranges_left, true);
343 			new_range = (struct reserved_range *)addr;
344 			addr = __physmem_alloc_range(size, align, 0, addr, ranges_left,
345 						     &ranges_left, die_on_oom);
346 			if (!addr)
347 				return 0;
348 			*new_range = *range;
349 			range->chain = new_range;
350 		}
351 		range->end = addr + size;
352 	}
353 	if (type != RR_VMEM) {
354 		boot_debug("%-14s 0x%016lx-0x%016lx %-20s align 0x%lx split %d\n", "Alloc topdown:",
355 			   addr, addr + size, get_rr_type_name(type), align, !!new_range);
356 	}
357 	range->start = addr;
358 	physmem_alloc_pos = addr;
359 	physmem_alloc_ranges = ranges_left;
360 	return addr;
361 }
362 
363 unsigned long physmem_alloc_or_die(enum reserved_range_type type, unsigned long size,
364 				   unsigned long align)
365 {
366 	return physmem_alloc(type, size, align, true);
367 }
368 
369 unsigned long get_physmem_alloc_pos(void)
370 {
371 	return physmem_alloc_pos;
372 }
373 
374 void dump_physmem_reserved(void)
375 {
376 	struct reserved_range *range;
377 	enum reserved_range_type t;
378 	unsigned long start, end;
379 
380 	boot_debug("Reserved memory ranges:\n");
381 	for_each_physmem_reserved_range(t, range, &start, &end) {
382 		if (end) {
383 			boot_debug("%-14s 0x%016lx-0x%016lx @%012lx chain %012lx\n",
384 				   get_rr_type_name(t), start, end, (unsigned long)range,
385 				   (unsigned long)range->chain);
386 		}
387 	}
388 }
389