xref: /openbmc/u-boot/drivers/misc/qfw.c (revision 1d2c0506)
1 /*
2  * (C) Copyright 2015 Miao Yan <yanmiaobest@gmail.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <command.h>
9 #include <errno.h>
10 #include <malloc.h>
11 #include <qfw.h>
12 #include <asm/io.h>
13 #ifdef CONFIG_GENERATE_ACPI_TABLE
14 #include <asm/tables.h>
15 #endif
16 #include <linux/list.h>
17 
18 static bool fwcfg_present;
19 static bool fwcfg_dma_present;
20 static struct fw_cfg_arch_ops *fwcfg_arch_ops;
21 
22 static LIST_HEAD(fw_list);
23 
24 #ifdef CONFIG_GENERATE_ACPI_TABLE
25 /*
26  * This function allocates memory for ACPI tables
27  *
28  * @entry : BIOS linker command entry which tells where to allocate memory
29  *          (either high memory or low memory)
30  * @addr  : The address that should be used for low memory allcation. If the
31  *          memory allocation request is 'ZONE_HIGH' then this parameter will
32  *          be ignored.
33  * @return: 0 on success, or negative value on failure
34  */
35 static int bios_linker_allocate(struct bios_linker_entry *entry, u32 *addr)
36 {
37 	uint32_t size, align;
38 	struct fw_file *file;
39 	unsigned long aligned_addr;
40 
41 	align = le32_to_cpu(entry->alloc.align);
42 	/* align must be power of 2 */
43 	if (align & (align - 1)) {
44 		printf("error: wrong alignment %u\n", align);
45 		return -EINVAL;
46 	}
47 
48 	file = qemu_fwcfg_find_file(entry->alloc.file);
49 	if (!file) {
50 		printf("error: can't find file %s\n", entry->alloc.file);
51 		return -ENOENT;
52 	}
53 
54 	size = be32_to_cpu(file->cfg.size);
55 
56 	/*
57 	 * ZONE_HIGH means we need to allocate from high memory, since
58 	 * malloc space is already at the end of RAM, so we directly use it.
59 	 * If allocation zone is ZONE_FSEG, then we use the 'addr' passed
60 	 * in which is low memory
61 	 */
62 	if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_HIGH) {
63 		aligned_addr = (unsigned long)memalign(align, size);
64 		if (!aligned_addr) {
65 			printf("error: allocating resource\n");
66 			return -ENOMEM;
67 		}
68 	} else if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_FSEG) {
69 		aligned_addr = ALIGN(*addr, align);
70 	} else {
71 		printf("error: invalid allocation zone\n");
72 		return -EINVAL;
73 	}
74 
75 	debug("bios_linker_allocate: allocate file %s, size %u, zone %d, align %u, addr 0x%lx\n",
76 	      file->cfg.name, size, entry->alloc.zone, align, aligned_addr);
77 
78 	qemu_fwcfg_read_entry(be16_to_cpu(file->cfg.select),
79 			      size, (void *)aligned_addr);
80 	file->addr = aligned_addr;
81 
82 	/* adjust address for low memory allocation */
83 	if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_FSEG)
84 		*addr = (aligned_addr + size);
85 
86 	return 0;
87 }
88 
89 /*
90  * This function patches ACPI tables previously loaded
91  * by bios_linker_allocate()
92  *
93  * @entry : BIOS linker command entry which tells how to patch
94  *          ACPI tables
95  * @return: 0 on success, or negative value on failure
96  */
97 static int bios_linker_add_pointer(struct bios_linker_entry *entry)
98 {
99 	struct fw_file *dest, *src;
100 	uint32_t offset = le32_to_cpu(entry->pointer.offset);
101 	uint64_t pointer = 0;
102 
103 	dest = qemu_fwcfg_find_file(entry->pointer.dest_file);
104 	if (!dest || !dest->addr)
105 		return -ENOENT;
106 	src = qemu_fwcfg_find_file(entry->pointer.src_file);
107 	if (!src || !src->addr)
108 		return -ENOENT;
109 
110 	debug("bios_linker_add_pointer: dest->addr 0x%lx, src->addr 0x%lx, offset 0x%x size %u, 0x%llx\n",
111 	      dest->addr, src->addr, offset, entry->pointer.size, pointer);
112 
113 	memcpy(&pointer, (char *)dest->addr + offset, entry->pointer.size);
114 	pointer	= le64_to_cpu(pointer);
115 	pointer += (unsigned long)src->addr;
116 	pointer	= cpu_to_le64(pointer);
117 	memcpy((char *)dest->addr + offset, &pointer, entry->pointer.size);
118 
119 	return 0;
120 }
121 
122 /*
123  * This function updates checksum fields of ACPI tables previously loaded
124  * by bios_linker_allocate()
125  *
126  * @entry : BIOS linker command entry which tells where to update ACPI table
127  *          checksums
128  * @return: 0 on success, or negative value on failure
129  */
130 static int bios_linker_add_checksum(struct bios_linker_entry *entry)
131 {
132 	struct fw_file *file;
133 	uint8_t *data, cksum = 0;
134 	uint8_t *cksum_start;
135 
136 	file = qemu_fwcfg_find_file(entry->cksum.file);
137 	if (!file || !file->addr)
138 		return -ENOENT;
139 
140 	data = (uint8_t *)(file->addr + le32_to_cpu(entry->cksum.offset));
141 	cksum_start = (uint8_t *)(file->addr + le32_to_cpu(entry->cksum.start));
142 	cksum = table_compute_checksum(cksum_start,
143 				       le32_to_cpu(entry->cksum.length));
144 	*data = cksum;
145 
146 	return 0;
147 }
148 
149 /* This function loads and patches ACPI tables provided by QEMU */
150 u32 write_acpi_tables(u32 addr)
151 {
152 	int i, ret = 0;
153 	struct fw_file *file;
154 	struct bios_linker_entry *table_loader;
155 	struct bios_linker_entry *entry;
156 	uint32_t size;
157 
158 	/* make sure fw_list is loaded */
159 	ret = qemu_fwcfg_read_firmware_list();
160 	if (ret) {
161 		printf("error: can't read firmware file list\n");
162 		return addr;
163 	}
164 
165 	file = qemu_fwcfg_find_file("etc/table-loader");
166 	if (!file) {
167 		printf("error: can't find etc/table-loader\n");
168 		return addr;
169 	}
170 
171 	size = be32_to_cpu(file->cfg.size);
172 	if ((size % sizeof(*entry)) != 0) {
173 		printf("error: table-loader maybe corrupted\n");
174 		return addr;
175 	}
176 
177 	table_loader = malloc(size);
178 	if (!table_loader) {
179 		printf("error: no memory for table-loader\n");
180 		return addr;
181 	}
182 
183 	qemu_fwcfg_read_entry(be16_to_cpu(file->cfg.select),
184 			      size, table_loader);
185 
186 	for (i = 0; i < (size / sizeof(*entry)); i++) {
187 		entry = table_loader + i;
188 		switch (le32_to_cpu(entry->command)) {
189 		case BIOS_LINKER_LOADER_COMMAND_ALLOCATE:
190 			ret = bios_linker_allocate(entry, &addr);
191 			if (ret)
192 				goto out;
193 			break;
194 		case BIOS_LINKER_LOADER_COMMAND_ADD_POINTER:
195 			ret = bios_linker_add_pointer(entry);
196 			if (ret)
197 				goto out;
198 			break;
199 		case BIOS_LINKER_LOADER_COMMAND_ADD_CHECKSUM:
200 			ret = bios_linker_add_checksum(entry);
201 			if (ret)
202 				goto out;
203 			break;
204 		default:
205 			break;
206 		}
207 	}
208 
209 out:
210 	if (ret) {
211 		struct fw_cfg_file_iter iter;
212 		for (file = qemu_fwcfg_file_iter_init(&iter);
213 		     !qemu_fwcfg_file_iter_end(&iter);
214 		     file = qemu_fwcfg_file_iter_next(&iter)) {
215 			if (file->addr) {
216 				free((void *)file->addr);
217 				file->addr = 0;
218 			}
219 		}
220 	}
221 
222 	free(table_loader);
223 	return addr;
224 }
225 #endif
226 
227 /* Read configuration item using fw_cfg PIO interface */
228 static void qemu_fwcfg_read_entry_pio(uint16_t entry,
229 		uint32_t size, void *address)
230 {
231 	debug("qemu_fwcfg_read_entry_pio: entry 0x%x, size %u address %p\n",
232 	      entry, size, address);
233 
234 	return fwcfg_arch_ops->arch_read_pio(entry, size, address);
235 }
236 
237 /* Read configuration item using fw_cfg DMA interface */
238 static void qemu_fwcfg_read_entry_dma(uint16_t entry,
239 		uint32_t size, void *address)
240 {
241 	struct fw_cfg_dma_access dma;
242 
243 	dma.length = cpu_to_be32(size);
244 	dma.address = cpu_to_be64((uintptr_t)address);
245 	dma.control = cpu_to_be32(FW_CFG_DMA_READ);
246 
247 	/*
248 	 * writting FW_CFG_INVALID will cause read operation to resume at
249 	 * last offset, otherwise read will start at offset 0
250 	 */
251 	if (entry != FW_CFG_INVALID)
252 		dma.control |= cpu_to_be32(FW_CFG_DMA_SELECT | (entry << 16));
253 
254 	barrier();
255 
256 	debug("qemu_fwcfg_read_entry_dma: entry 0x%x, size %u address %p, control 0x%x\n",
257 	      entry, size, address, be32_to_cpu(dma.control));
258 
259 	fwcfg_arch_ops->arch_read_dma(&dma);
260 }
261 
262 bool qemu_fwcfg_present(void)
263 {
264 	return fwcfg_present;
265 }
266 
267 bool qemu_fwcfg_dma_present(void)
268 {
269 	return fwcfg_dma_present;
270 }
271 
272 void qemu_fwcfg_read_entry(uint16_t entry, uint32_t length, void *address)
273 {
274 	if (fwcfg_dma_present)
275 		qemu_fwcfg_read_entry_dma(entry, length, address);
276 	else
277 		qemu_fwcfg_read_entry_pio(entry, length, address);
278 }
279 
280 int qemu_fwcfg_online_cpus(void)
281 {
282 	uint16_t nb_cpus;
283 
284 	if (!fwcfg_present)
285 		return -ENODEV;
286 
287 	qemu_fwcfg_read_entry(FW_CFG_NB_CPUS, 2, &nb_cpus);
288 
289 	return le16_to_cpu(nb_cpus);
290 }
291 
292 int qemu_fwcfg_read_firmware_list(void)
293 {
294 	int i;
295 	uint32_t count;
296 	struct fw_file *file;
297 	struct list_head *entry;
298 
299 	/* don't read it twice */
300 	if (!list_empty(&fw_list))
301 		return 0;
302 
303 	qemu_fwcfg_read_entry(FW_CFG_FILE_DIR, 4, &count);
304 	if (!count)
305 		return 0;
306 
307 	count = be32_to_cpu(count);
308 	for (i = 0; i < count; i++) {
309 		file = malloc(sizeof(*file));
310 		if (!file) {
311 			printf("error: allocating resource\n");
312 			goto err;
313 		}
314 		qemu_fwcfg_read_entry(FW_CFG_INVALID,
315 				      sizeof(struct fw_cfg_file), &file->cfg);
316 		file->addr = 0;
317 		list_add_tail(&file->list, &fw_list);
318 	}
319 
320 	return 0;
321 
322 err:
323 	list_for_each(entry, &fw_list) {
324 		file = list_entry(entry, struct fw_file, list);
325 		free(file);
326 	}
327 
328 	return -ENOMEM;
329 }
330 
331 struct fw_file *qemu_fwcfg_find_file(const char *name)
332 {
333 	struct list_head *entry;
334 	struct fw_file *file;
335 
336 	list_for_each(entry, &fw_list) {
337 		file = list_entry(entry, struct fw_file, list);
338 		if (!strcmp(file->cfg.name, name))
339 			return file;
340 	}
341 
342 	return NULL;
343 }
344 
345 struct fw_file *qemu_fwcfg_file_iter_init(struct fw_cfg_file_iter *iter)
346 {
347 	iter->entry = fw_list.next;
348 	return list_entry((struct list_head *)iter->entry,
349 			  struct fw_file, list);
350 }
351 
352 struct fw_file *qemu_fwcfg_file_iter_next(struct fw_cfg_file_iter *iter)
353 {
354 	iter->entry = ((struct list_head *)iter->entry)->next;
355 	return list_entry((struct list_head *)iter->entry,
356 			  struct fw_file, list);
357 }
358 
359 bool qemu_fwcfg_file_iter_end(struct fw_cfg_file_iter *iter)
360 {
361 	return iter->entry == &fw_list;
362 }
363 
364 void qemu_fwcfg_init(struct fw_cfg_arch_ops *ops)
365 {
366 	uint32_t qemu;
367 	uint32_t dma_enabled;
368 
369 	fwcfg_present = false;
370 	fwcfg_dma_present = false;
371 	fwcfg_arch_ops = NULL;
372 
373 	if (!ops || !ops->arch_read_pio || !ops->arch_read_dma)
374 		return;
375 	fwcfg_arch_ops = ops;
376 
377 	qemu_fwcfg_read_entry_pio(FW_CFG_SIGNATURE, 4, &qemu);
378 	if (be32_to_cpu(qemu) == QEMU_FW_CFG_SIGNATURE)
379 		fwcfg_present = true;
380 
381 	if (fwcfg_present) {
382 		qemu_fwcfg_read_entry_pio(FW_CFG_ID, 1, &dma_enabled);
383 		if (dma_enabled & FW_CFG_DMA_ENABLED)
384 			fwcfg_dma_present = true;
385 	}
386 }
387