xref: /openbmc/u-boot/drivers/misc/qfw.c (revision 3ebd892f)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2015 Miao Yan <yanmiaobest@gmail.com>
4  */
5 
6 #include <common.h>
7 #include <command.h>
8 #include <errno.h>
9 #include <malloc.h>
10 #include <qfw.h>
11 #include <asm/io.h>
12 #ifdef CONFIG_GENERATE_ACPI_TABLE
13 #include <asm/tables.h>
14 #endif
15 #include <linux/list.h>
16 
17 static bool fwcfg_present;
18 static bool fwcfg_dma_present;
19 static struct fw_cfg_arch_ops *fwcfg_arch_ops;
20 
21 static LIST_HEAD(fw_list);
22 
23 #ifdef CONFIG_GENERATE_ACPI_TABLE
24 /*
25  * This function allocates memory for ACPI tables
26  *
27  * @entry : BIOS linker command entry which tells where to allocate memory
28  *          (either high memory or low memory)
29  * @addr  : The address that should be used for low memory allcation. If the
30  *          memory allocation request is 'ZONE_HIGH' then this parameter will
31  *          be ignored.
32  * @return: 0 on success, or negative value on failure
33  */
34 static int bios_linker_allocate(struct bios_linker_entry *entry, ulong *addr)
35 {
36 	uint32_t size, align;
37 	struct fw_file *file;
38 	unsigned long aligned_addr;
39 
40 	align = le32_to_cpu(entry->alloc.align);
41 	/* align must be power of 2 */
42 	if (align & (align - 1)) {
43 		printf("error: wrong alignment %u\n", align);
44 		return -EINVAL;
45 	}
46 
47 	file = qemu_fwcfg_find_file(entry->alloc.file);
48 	if (!file) {
49 		printf("error: can't find file %s\n", entry->alloc.file);
50 		return -ENOENT;
51 	}
52 
53 	size = be32_to_cpu(file->cfg.size);
54 
55 	/*
56 	 * ZONE_HIGH means we need to allocate from high memory, since
57 	 * malloc space is already at the end of RAM, so we directly use it.
58 	 * If allocation zone is ZONE_FSEG, then we use the 'addr' passed
59 	 * in which is low memory
60 	 */
61 	if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_HIGH) {
62 		aligned_addr = (unsigned long)memalign(align, size);
63 		if (!aligned_addr) {
64 			printf("error: allocating resource\n");
65 			return -ENOMEM;
66 		}
67 	} else if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_FSEG) {
68 		aligned_addr = ALIGN(*addr, align);
69 	} else {
70 		printf("error: invalid allocation zone\n");
71 		return -EINVAL;
72 	}
73 
74 	debug("bios_linker_allocate: allocate file %s, size %u, zone %d, align %u, addr 0x%lx\n",
75 	      file->cfg.name, size, entry->alloc.zone, align, aligned_addr);
76 
77 	qemu_fwcfg_read_entry(be16_to_cpu(file->cfg.select),
78 			      size, (void *)aligned_addr);
79 	file->addr = aligned_addr;
80 
81 	/* adjust address for low memory allocation */
82 	if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_FSEG)
83 		*addr = (aligned_addr + size);
84 
85 	return 0;
86 }
87 
88 /*
89  * This function patches ACPI tables previously loaded
90  * by bios_linker_allocate()
91  *
92  * @entry : BIOS linker command entry which tells how to patch
93  *          ACPI tables
94  * @return: 0 on success, or negative value on failure
95  */
96 static int bios_linker_add_pointer(struct bios_linker_entry *entry)
97 {
98 	struct fw_file *dest, *src;
99 	uint32_t offset = le32_to_cpu(entry->pointer.offset);
100 	uint64_t pointer = 0;
101 
102 	dest = qemu_fwcfg_find_file(entry->pointer.dest_file);
103 	if (!dest || !dest->addr)
104 		return -ENOENT;
105 	src = qemu_fwcfg_find_file(entry->pointer.src_file);
106 	if (!src || !src->addr)
107 		return -ENOENT;
108 
109 	debug("bios_linker_add_pointer: dest->addr 0x%lx, src->addr 0x%lx, offset 0x%x size %u, 0x%llx\n",
110 	      dest->addr, src->addr, offset, entry->pointer.size, pointer);
111 
112 	memcpy(&pointer, (char *)dest->addr + offset, entry->pointer.size);
113 	pointer	= le64_to_cpu(pointer);
114 	pointer += (unsigned long)src->addr;
115 	pointer	= cpu_to_le64(pointer);
116 	memcpy((char *)dest->addr + offset, &pointer, entry->pointer.size);
117 
118 	return 0;
119 }
120 
121 /*
122  * This function updates checksum fields of ACPI tables previously loaded
123  * by bios_linker_allocate()
124  *
125  * @entry : BIOS linker command entry which tells where to update ACPI table
126  *          checksums
127  * @return: 0 on success, or negative value on failure
128  */
129 static int bios_linker_add_checksum(struct bios_linker_entry *entry)
130 {
131 	struct fw_file *file;
132 	uint8_t *data, cksum = 0;
133 	uint8_t *cksum_start;
134 
135 	file = qemu_fwcfg_find_file(entry->cksum.file);
136 	if (!file || !file->addr)
137 		return -ENOENT;
138 
139 	data = (uint8_t *)(file->addr + le32_to_cpu(entry->cksum.offset));
140 	cksum_start = (uint8_t *)(file->addr + le32_to_cpu(entry->cksum.start));
141 	cksum = table_compute_checksum(cksum_start,
142 				       le32_to_cpu(entry->cksum.length));
143 	*data = cksum;
144 
145 	return 0;
146 }
147 
148 /* This function loads and patches ACPI tables provided by QEMU */
149 ulong write_acpi_tables(ulong addr)
150 {
151 	int i, ret = 0;
152 	struct fw_file *file;
153 	struct bios_linker_entry *table_loader;
154 	struct bios_linker_entry *entry;
155 	uint32_t size;
156 
157 	/* make sure fw_list is loaded */
158 	ret = qemu_fwcfg_read_firmware_list();
159 	if (ret) {
160 		printf("error: can't read firmware file list\n");
161 		return addr;
162 	}
163 
164 	file = qemu_fwcfg_find_file("etc/table-loader");
165 	if (!file) {
166 		printf("error: can't find etc/table-loader\n");
167 		return addr;
168 	}
169 
170 	size = be32_to_cpu(file->cfg.size);
171 	if ((size % sizeof(*entry)) != 0) {
172 		printf("error: table-loader maybe corrupted\n");
173 		return addr;
174 	}
175 
176 	table_loader = malloc(size);
177 	if (!table_loader) {
178 		printf("error: no memory for table-loader\n");
179 		return addr;
180 	}
181 
182 	qemu_fwcfg_read_entry(be16_to_cpu(file->cfg.select),
183 			      size, table_loader);
184 
185 	for (i = 0; i < (size / sizeof(*entry)); i++) {
186 		entry = table_loader + i;
187 		switch (le32_to_cpu(entry->command)) {
188 		case BIOS_LINKER_LOADER_COMMAND_ALLOCATE:
189 			ret = bios_linker_allocate(entry, &addr);
190 			if (ret)
191 				goto out;
192 			break;
193 		case BIOS_LINKER_LOADER_COMMAND_ADD_POINTER:
194 			ret = bios_linker_add_pointer(entry);
195 			if (ret)
196 				goto out;
197 			break;
198 		case BIOS_LINKER_LOADER_COMMAND_ADD_CHECKSUM:
199 			ret = bios_linker_add_checksum(entry);
200 			if (ret)
201 				goto out;
202 			break;
203 		default:
204 			break;
205 		}
206 	}
207 
208 out:
209 	if (ret) {
210 		struct fw_cfg_file_iter iter;
211 		for (file = qemu_fwcfg_file_iter_init(&iter);
212 		     !qemu_fwcfg_file_iter_end(&iter);
213 		     file = qemu_fwcfg_file_iter_next(&iter)) {
214 			if (file->addr) {
215 				free((void *)file->addr);
216 				file->addr = 0;
217 			}
218 		}
219 	}
220 
221 	free(table_loader);
222 	return addr;
223 }
224 
225 ulong acpi_get_rsdp_addr(void)
226 {
227 	struct fw_file *file;
228 
229 	file = qemu_fwcfg_find_file("etc/acpi/rsdp");
230 	return file->addr;
231 }
232 #endif
233 
234 /* Read configuration item using fw_cfg PIO interface */
235 static void qemu_fwcfg_read_entry_pio(uint16_t entry,
236 		uint32_t size, void *address)
237 {
238 	debug("qemu_fwcfg_read_entry_pio: entry 0x%x, size %u address %p\n",
239 	      entry, size, address);
240 
241 	return fwcfg_arch_ops->arch_read_pio(entry, size, address);
242 }
243 
244 /* Read configuration item using fw_cfg DMA interface */
245 static void qemu_fwcfg_read_entry_dma(uint16_t entry,
246 		uint32_t size, void *address)
247 {
248 	struct fw_cfg_dma_access dma;
249 
250 	dma.length = cpu_to_be32(size);
251 	dma.address = cpu_to_be64((uintptr_t)address);
252 	dma.control = cpu_to_be32(FW_CFG_DMA_READ);
253 
254 	/*
255 	 * writting FW_CFG_INVALID will cause read operation to resume at
256 	 * last offset, otherwise read will start at offset 0
257 	 */
258 	if (entry != FW_CFG_INVALID)
259 		dma.control |= cpu_to_be32(FW_CFG_DMA_SELECT | (entry << 16));
260 
261 	barrier();
262 
263 	debug("qemu_fwcfg_read_entry_dma: entry 0x%x, size %u address %p, control 0x%x\n",
264 	      entry, size, address, be32_to_cpu(dma.control));
265 
266 	fwcfg_arch_ops->arch_read_dma(&dma);
267 }
268 
269 bool qemu_fwcfg_present(void)
270 {
271 	return fwcfg_present;
272 }
273 
274 bool qemu_fwcfg_dma_present(void)
275 {
276 	return fwcfg_dma_present;
277 }
278 
279 void qemu_fwcfg_read_entry(uint16_t entry, uint32_t length, void *address)
280 {
281 	if (fwcfg_dma_present)
282 		qemu_fwcfg_read_entry_dma(entry, length, address);
283 	else
284 		qemu_fwcfg_read_entry_pio(entry, length, address);
285 }
286 
287 int qemu_fwcfg_online_cpus(void)
288 {
289 	uint16_t nb_cpus;
290 
291 	if (!fwcfg_present)
292 		return -ENODEV;
293 
294 	qemu_fwcfg_read_entry(FW_CFG_NB_CPUS, 2, &nb_cpus);
295 
296 	return le16_to_cpu(nb_cpus);
297 }
298 
299 int qemu_fwcfg_read_firmware_list(void)
300 {
301 	int i;
302 	uint32_t count;
303 	struct fw_file *file;
304 	struct list_head *entry;
305 
306 	/* don't read it twice */
307 	if (!list_empty(&fw_list))
308 		return 0;
309 
310 	qemu_fwcfg_read_entry(FW_CFG_FILE_DIR, 4, &count);
311 	if (!count)
312 		return 0;
313 
314 	count = be32_to_cpu(count);
315 	for (i = 0; i < count; i++) {
316 		file = malloc(sizeof(*file));
317 		if (!file) {
318 			printf("error: allocating resource\n");
319 			goto err;
320 		}
321 		qemu_fwcfg_read_entry(FW_CFG_INVALID,
322 				      sizeof(struct fw_cfg_file), &file->cfg);
323 		file->addr = 0;
324 		list_add_tail(&file->list, &fw_list);
325 	}
326 
327 	return 0;
328 
329 err:
330 	list_for_each(entry, &fw_list) {
331 		file = list_entry(entry, struct fw_file, list);
332 		free(file);
333 	}
334 
335 	return -ENOMEM;
336 }
337 
338 struct fw_file *qemu_fwcfg_find_file(const char *name)
339 {
340 	struct list_head *entry;
341 	struct fw_file *file;
342 
343 	list_for_each(entry, &fw_list) {
344 		file = list_entry(entry, struct fw_file, list);
345 		if (!strcmp(file->cfg.name, name))
346 			return file;
347 	}
348 
349 	return NULL;
350 }
351 
352 struct fw_file *qemu_fwcfg_file_iter_init(struct fw_cfg_file_iter *iter)
353 {
354 	iter->entry = fw_list.next;
355 	return list_entry((struct list_head *)iter->entry,
356 			  struct fw_file, list);
357 }
358 
359 struct fw_file *qemu_fwcfg_file_iter_next(struct fw_cfg_file_iter *iter)
360 {
361 	iter->entry = ((struct list_head *)iter->entry)->next;
362 	return list_entry((struct list_head *)iter->entry,
363 			  struct fw_file, list);
364 }
365 
366 bool qemu_fwcfg_file_iter_end(struct fw_cfg_file_iter *iter)
367 {
368 	return iter->entry == &fw_list;
369 }
370 
371 void qemu_fwcfg_init(struct fw_cfg_arch_ops *ops)
372 {
373 	uint32_t qemu;
374 	uint32_t dma_enabled;
375 
376 	fwcfg_present = false;
377 	fwcfg_dma_present = false;
378 	fwcfg_arch_ops = NULL;
379 
380 	if (!ops || !ops->arch_read_pio || !ops->arch_read_dma)
381 		return;
382 	fwcfg_arch_ops = ops;
383 
384 	qemu_fwcfg_read_entry_pio(FW_CFG_SIGNATURE, 4, &qemu);
385 	if (be32_to_cpu(qemu) == QEMU_FW_CFG_SIGNATURE)
386 		fwcfg_present = true;
387 
388 	if (fwcfg_present) {
389 		qemu_fwcfg_read_entry_pio(FW_CFG_ID, 1, &dma_enabled);
390 		if (dma_enabled & FW_CFG_DMA_ENABLED)
391 			fwcfg_dma_present = true;
392 	}
393 }
394