summaryrefslogtreecommitdiff
path: root/cmd/qemu_fw_cfg.c
blob: aab6b1a452604211d8ddc0bd9192d919007ddcb8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
/*
 * (C) Copyright 2015 Miao Yan <yanmiaobest@gmail.com>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <command.h>
#include <errno.h>
#include <malloc.h>
#include <qemu_fw_cfg.h>
#include <asm/io.h>
#include <linux/list.h>

static bool fwcfg_present;
static bool fwcfg_dma_present;

static LIST_HEAD(fw_list);

/* Read configuration item using fw_cfg PIO interface */
static void qemu_fwcfg_read_entry_pio(uint16_t entry,
		uint32_t size, void *address)
{
	uint32_t i = 0;
	uint8_t *data = address;

	/*
	 * writting FW_CFG_INVALID will cause read operation to resume at
	 * last offset, otherwise read will start at offset 0
	 */
	if (entry != FW_CFG_INVALID)
		outw(entry, FW_CONTROL_PORT);
	while (size--)
		data[i++] = inb(FW_DATA_PORT);
}

/* Read configuration item using fw_cfg DMA interface */
static void qemu_fwcfg_read_entry_dma(uint16_t entry,
		uint32_t size, void *address)
{
	struct fw_cfg_dma_access dma;

	dma.length = cpu_to_be32(size);
	dma.address = cpu_to_be64((uintptr_t)address);
	dma.control = cpu_to_be32(FW_CFG_DMA_READ);

	/*
	 * writting FW_CFG_INVALID will cause read operation to resume at
	 * last offset, otherwise read will start at offset 0
	 */
	if (entry != FW_CFG_INVALID)
		dma.control |= cpu_to_be32(FW_CFG_DMA_SELECT | (entry << 16));

	barrier();

	debug("qemu_fwcfg_dma_read_entry: addr %p, length %u control 0x%x\n",
	      address, size, be32_to_cpu(dma.control));

	outl(cpu_to_be32((uint32_t)&dma), FW_DMA_PORT_HIGH);

	while (be32_to_cpu(dma.control) & ~FW_CFG_DMA_ERROR)
		__asm__ __volatile__ ("pause");
}

bool qemu_fwcfg_present(void)
{
	return fwcfg_present;
}

bool qemu_fwcfg_dma_present(void)
{
	return fwcfg_dma_present;
}

void qemu_fwcfg_read_entry(uint16_t entry, uint32_t length, void *address)
{
	if (fwcfg_dma_present)
		qemu_fwcfg_read_entry_dma(entry, length, address);
	else
		qemu_fwcfg_read_entry_pio(entry, length, address);
}

int qemu_fwcfg_online_cpus(void)
{
	uint16_t nb_cpus;

	if (!fwcfg_present)
		return -ENODEV;

	qemu_fwcfg_read_entry(FW_CFG_NB_CPUS, 2, &nb_cpus);

	return le16_to_cpu(nb_cpus);
}

/*
 * This function prepares kernel for zboot. It loads kernel data
 * to 'load_addr', initrd to 'initrd_addr' and kernel command
 * line using qemu fw_cfg interface.
 */
static int qemu_fwcfg_setup_kernel(void *load_addr, void *initrd_addr)
{
	char *data_addr;
	uint32_t setup_size, kernel_size, cmdline_size, initrd_size;

	qemu_fwcfg_read_entry(FW_CFG_SETUP_SIZE, 4, &setup_size);
	qemu_fwcfg_read_entry(FW_CFG_KERNEL_SIZE, 4, &kernel_size);

	if (setup_size == 0 || kernel_size == 0) {
		printf("warning: no kernel available\n");
		return -1;
	}

	data_addr = load_addr;
	qemu_fwcfg_read_entry(FW_CFG_SETUP_DATA,
			      le32_to_cpu(setup_size), data_addr);
	data_addr += le32_to_cpu(setup_size);

	qemu_fwcfg_read_entry(FW_CFG_KERNEL_DATA,
			      le32_to_cpu(kernel_size), data_addr);
	data_addr += le32_to_cpu(kernel_size);

	data_addr = initrd_addr;
	qemu_fwcfg_read_entry(FW_CFG_INITRD_SIZE, 4, &initrd_size);
	if (initrd_size == 0) {
		printf("warning: no initrd available\n");
	} else {
		qemu_fwcfg_read_entry(FW_CFG_INITRD_DATA,
				      le32_to_cpu(initrd_size), data_addr);
		data_addr += le32_to_cpu(initrd_size);
	}

	qemu_fwcfg_read_entry(FW_CFG_CMDLINE_SIZE, 4, &cmdline_size);
	if (cmdline_size) {
		qemu_fwcfg_read_entry(FW_CFG_CMDLINE_DATA,
				      le32_to_cpu(cmdline_size), data_addr);
		/*
		 * if kernel cmdline only contains '\0', (e.g. no -append
		 * when invoking qemu), do not update bootargs
		 */
		if (*data_addr != '\0') {
			if (setenv("bootargs", data_addr) < 0)
				printf("warning: unable to change bootargs\n");
		}
	}

	printf("loading kernel to address %p size %x", load_addr,
	       le32_to_cpu(kernel_size));
	if (initrd_size)
		printf(" initrd %p size %x\n",
		       initrd_addr,
		       le32_to_cpu(initrd_size));
	else
		printf("\n");

	return 0;
}

int qemu_fwcfg_read_firmware_list(void)
{
	int i;
	uint32_t count;
	struct fw_file *file;
	struct list_head *entry;

	/* don't read it twice */
	if (!list_empty(&fw_list))
		return 0;

	qemu_fwcfg_read_entry(FW_CFG_FILE_DIR, 4, &count);
	if (!count)
		return 0;

	count = be32_to_cpu(count);
	for (i = 0; i < count; i++) {
		file = malloc(sizeof(*file));
		if (!file) {
			printf("error: allocating resource\n");
			goto err;
		}
		qemu_fwcfg_read_entry(FW_CFG_INVALID,
				      sizeof(struct fw_cfg_file), &file->cfg);
		file->addr = 0;
		list_add_tail(&file->list, &fw_list);
	}

	return 0;

err:
	list_for_each(entry, &fw_list) {
		file = list_entry(entry, struct fw_file, list);
		free(file);
	}

	return -ENOMEM;
}

struct fw_file *qemu_fwcfg_find_file(const char *name)
{
	struct list_head *entry;
	struct fw_file *file;

	list_for_each(entry, &fw_list) {
		file = list_entry(entry, struct fw_file, list);
		if (!strcmp(file->cfg.name, name))
			return file;
	}

	return NULL;
}

struct fw_file *qemu_fwcfg_file_iter_init(struct fw_cfg_file_iter *iter)
{
	iter->entry = fw_list.next;
	return list_entry(iter->entry, struct fw_file, list);
}

struct fw_file *qemu_fwcfg_file_iter_next(struct fw_cfg_file_iter *iter)
{
	iter->entry = iter->entry->next;
	return list_entry(iter->entry, struct fw_file, list);
}

bool qemu_fwcfg_file_iter_end(struct fw_cfg_file_iter *iter)
{
	return iter->entry == &fw_list;
}

static int qemu_fwcfg_list_firmware(void)
{
	int ret;
	struct fw_cfg_file_iter iter;
	struct fw_file *file;

	/* make sure fw_list is loaded */
	ret = qemu_fwcfg_read_firmware_list();
	if (ret)
		return ret;


	for (file = qemu_fwcfg_file_iter_init(&iter);
	     !qemu_fwcfg_file_iter_end(&iter);
	     file = qemu_fwcfg_file_iter_next(&iter)) {
		printf("%-56s\n", file->cfg.name);
	}

	return 0;
}

void qemu_fwcfg_init(void)
{
	uint32_t qemu;
	uint32_t dma_enabled;

	fwcfg_present = false;
	fwcfg_dma_present = false;

	qemu_fwcfg_read_entry_pio(FW_CFG_SIGNATURE, 4, &qemu);
	if (be32_to_cpu(qemu) == QEMU_FW_CFG_SIGNATURE)
		fwcfg_present = true;

	if (fwcfg_present) {
		qemu_fwcfg_read_entry_pio(FW_CFG_ID, 1, &dma_enabled);
		if (dma_enabled & FW_CFG_DMA_ENABLED)
			fwcfg_dma_present = true;
	}
}

static int qemu_fwcfg_do_list(cmd_tbl_t *cmdtp, int flag,
		int argc, char * const argv[])
{
	if (qemu_fwcfg_list_firmware() < 0)
		return CMD_RET_FAILURE;

	return 0;
}

static int qemu_fwcfg_do_cpus(cmd_tbl_t *cmdtp, int flag,
		int argc, char * const argv[])
{
	int ret = qemu_fwcfg_online_cpus();
	if (ret < 0) {
		printf("QEMU fw_cfg interface not found\n");
		return CMD_RET_FAILURE;
	}

	printf("%d cpu(s) online\n", qemu_fwcfg_online_cpus());

	return 0;
}

static int qemu_fwcfg_do_load(cmd_tbl_t *cmdtp, int flag,
		int argc, char * const argv[])
{
	char *env;
	void *load_addr;
	void *initrd_addr;

	env = getenv("loadaddr");
	load_addr = env ?
		(void *)simple_strtoul(env, NULL, 16) :
		(void *)CONFIG_LOADADDR;

	env = getenv("ramdiskaddr");
	initrd_addr = env ?
		(void *)simple_strtoul(env, NULL, 16) :
		(void *)CONFIG_RAMDISK_ADDR;

	if (argc == 2) {
		load_addr = (void *)simple_strtoul(argv[0], NULL, 16);
		initrd_addr = (void *)simple_strtoul(argv[1], NULL, 16);
	} else if (argc == 1) {
		load_addr = (void *)simple_strtoul(argv[0], NULL, 16);
	}

	return qemu_fwcfg_setup_kernel(load_addr, initrd_addr);
}

static cmd_tbl_t fwcfg_commands[] = {
	U_BOOT_CMD_MKENT(list, 0, 1, qemu_fwcfg_do_list, "", ""),
	U_BOOT_CMD_MKENT(cpus, 0, 1, qemu_fwcfg_do_cpus, "", ""),
	U_BOOT_CMD_MKENT(load, 2, 1, qemu_fwcfg_do_load, "", ""),
};

static int do_qemu_fw(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	int ret;
	cmd_tbl_t *fwcfg_cmd;

	if (!qemu_fwcfg_present()) {
		printf("QEMU fw_cfg interface not found\n");
		return CMD_RET_USAGE;
	}

	fwcfg_cmd = find_cmd_tbl(argv[1], fwcfg_commands,
				 ARRAY_SIZE(fwcfg_commands));
	argc -= 2;
	argv += 2;
	if (!fwcfg_cmd || argc > fwcfg_cmd->maxargs)
		return CMD_RET_USAGE;

	ret = fwcfg_cmd->cmd(fwcfg_cmd, flag, argc, argv);

	return cmd_process_error(fwcfg_cmd, ret);
}

U_BOOT_CMD(
	qfw,	4,	1,	do_qemu_fw,
	"QEMU firmware interface",
	"<command>\n"
	"    - list                             : print firmware(s) currently loaded\n"
	"    - cpus                             : print online cpu number\n"
	"    - load <kernel addr> <initrd addr> : load kernel and initrd (if any), and setup for zboot\n"
)